May 2021 Imaging Case of the Month: A Growing Indeterminate Solitary Nodule

Joseph Jeehoon Kim, MD^°

Kenneth K. Sakata, MD^‡

Natalya Azadeh, MD, MPH^‡

Maxwell Smith, MD^↑

Michael B. Gotway, MD^†

^°Department of Medicine, Mayo Clinic Arizona

^↑Department of Laboratory Medicine and Pathology, Mayo Clinic Arizona

^‡Division of Pulmonary and Critical Care Medicine, Mayo Clinic Arizona

^†Department of Radiology, Mayo Clinic, Arizona

5777 East Mayo Boulevard

Phoenix, Arizona 85054

A 58-year-old woman with a history of orthotopic heart transplant, performed for Adriamycin-induced cardiomyopathy, treated with mycophenolate and tacrolimus, presented for routine interval follow up. The patient’s past medical history was significant for follicular thyroid carcinoma treated with total thyroidectomy and bilateral breast carcinoma in remission as well as hypothyroidism and type II diabetes mellitus. In addition to tacrolimus and mycophenolate, the patient’s medications included aspirin, insulin, itraconazole (for anti-fungal prophylaxis), levothyroxine, prednisone (tapering since transplant), and valganciclovir. The patient recently complained of rhinorrhea and cough productive of brown-tinged sputum, improving over the previous 2 weeks; she denied fever, chills, shortness of breath, night sweats chest pain, or gastrointestinal symptoms.

Physical examination showed the patient to be afebrile with normal heart and respiratory rates and blood pressure. Her room air oxygen saturation was 99%.

The patient’s complete blood count and serum chemistries showed largely normal values, with the white blood cell count at the upper normal at 9.7 x 10⁹ /L (normal, 4-10 x 10⁹ /L). Her liver function testing and renal function testing parameters were also within normal limits. Echocardiography showed normal left ventricular systolic function. The patient underwent frontal chest radiography (Figure 1).

Figure 1. Frontal chest radiography.

Which of the following represents an appropriate interpretation of her frontal chest radiograph? (Click on the correct answer to be directed to the second of nine pages). 

1. Frontal chest radiography shows a right pleural effusion
2. Frontal chest radiograph shows a left apical nodule
3. Frontal chest radiography shows multifocal consolidation
4. Frontal chest radiography shows peribronchial and mediastinal lymphadenopathy
5. Frontal chest radiography shows cardiomegaly

Cite as: Kim JHJ, Sakata KK, Azadeh N, Smith M, Gotway MB. May 2021 Imaging Case of the Month: A Growing Indeterminate Solitary Nodule. Southwest J Pulm Crit Care Med. 2021;229(5):88-99. doi: https://doi.org/10.13175/swjpcc013-21 PDF

Medical Image of the Month: Severe Acute Respiratory Distress Syndrome and Embolic Strokes from Polymethylmethacrylate (PMMA) Embolization

Figure 1. The contrast-enhanced CT of the chest on the left (Panel A) was acquired at the time of admission. The contrast-enhanced CT of the chest on the right (Panel B) was obtained 3 days into the hospitalization. The initial study demonstrated ground glass opacities most pronounced in the upper lobes, left greater than right. The follow up CT demonstrated marked progression of her airspace disease bilaterally, consistent with the clinical picture of the adult respiratory distress syndrome (ARDS).

Figure 2. An axial susceptibility weighted image (SWI) of the brain demonstrates extensive foci of susceptibility artifact (black dots) most pronounced in the genu and splenium of the corpus callosum (blue arrows) and the bilateral internal capsules (red arrows) – most consistent with embolic phenomenon.

A 35-year-old lady with a history of depression and anxiety presented to the emergency room with worsening shortness of breath after receiving polymethylmethacrylate (PMMA) injections in her buttock for cosmetic purposes in Mexico. Immediately after the injection in the outpatient office, she became acutely short of breath, tachypneic, and tachycardic. She was brought to the emergency room where she was hypoxic with oxygen saturations in the low 80s on a non-rebreather, tachypneic with a respiratory rate in the 40s, and tachycardic with heart rates in 140s. She was emergently intubated. A CTA of the chest demonstrated bilateral ground glass opacities throughout, most pronounced in the upper lobes which progressed to significant bilateral airspace disease consistent with acute respiratory distress syndrome (Figure 1). Her neurological examination declined over the course of her hospitalization. An MRI of the brain with contrast demonstrated bilateral foci of susceptibility artifact throughout the entirety of the brain most consistent with an embolic phenomenon in the setting of a suspected right-to-left shunt (Figure 2). Her mental status did not improve during her hospital course, and her family was deciding on whether to pursue comfort measures.

Discussion: Embolic complications of PMMA have been documented in the literature in relation to interventional procedures of the spine where it is used as a cement (i.e. vertebroplasty/kyphoplasty) (1). In those instances, the emboli are radiopaque and can be identified on conventional imaging modalities such as chest radiography or CT imaging (2). In the case of our patient, we were not able to confirm the exact formulation of the PMMA, but we suspect that it was delivered in the form of a dermal filler which was likely in the form of particles/microspheres. Migration of the particles/microspheres in the form of vascular emboli can occur if injected into blood vessels during procedures (3).

Sooraj Kumar MBBS¹, Sharanyah Srinivasan MBBS¹, and Tammer El-Aini MD²

¹Banner University Medical Center – South Campus, Department of Internal Medicine

²Banner University Medical Center – Main Campus, Department of Pulmonary and Critical Care

References

1. Abdul-Jalil Y, Bartels J, Alberti O, Becker R. Delayed presentation of pulmonary polymethylmethacrylate emboli after percutaneous vertebroplasty. Spine (Phila Pa 1976). 2007 Sep 15;32(20):E589-93. [CrossRef] [PubMed]
2. Yeom JS, Kim WJ, Choy WS, Lee CK, Chang BS, Kang JW. Leakage of cement in percutaneous transpedicular vertebroplasty for painful osteoporotic compression fractures. J Bone Joint Surg Br. 2003 Jan;85(1):83-9. [CrossRef] [PubMed]
3. Lemperle G, Morhenn VB, Pestonjamasp V, Gallo RL. Migration studies and histology of injectable microspheres of different sizes in mice. Plast Reconstr Surg. 2004 Apr 15;113(5):1380-90. [CrossRef] [PubMed]

Cite as: Kumar S, Srinivasan S, El-Aini T. Medical image of the month: severe acute respiratory distress syndrome and embolic strokes from polymethylmethacrylate (PMMA) embolization. Southwest J Pulm Crit Care. 2021;22(4):86-7. doi: https://doi.org/10.13175/swjpcc008-21 PDF

Medical Image of the Month: Pulmonary Aspergillus Overlap Syndrome Presenting with ABPA, Multiple Bilateral Aspergillomas

Figure 1. Representative images from thoracic CT scan in soft tissue windows showing multiple Aspergillomas (arrows).

Introduction

Aspergillus is a ubiquitous fungal organism that causes a variety of pulmonary manifestations, both in immune-competent and immune-compromised patients. It can vary from simple colonization, Aspergilloma, ABPA to Chronic Pulmonary Aspergillosis (CPA) and Invasive Pulmonary Aspergillosis (IPA) (1). ABPA is the most frequently recognized manifestation of allergic aspergillosis, caused by the immunological reactions mounted against Asp. fumigatus. Aspergillomas are rounded conglomerates of fungal hyphae, fibrin, mucus and cellular debris that arise in pulmonary cavities, as a late manifestation of CPA. Chronic pulmonary aspergillosis (CPA) is a long-term aspergillus infection of the lung. The most common form of CPA is chronic cavitary pulmonary aspergillosis (CCPA), which untreated may progress to chronic fibrosing pulmonary aspergillosis. Aspergillus overlap syndrome is defined as the occurrence of more than one form of aspergillus disease (e.g., ABPA with Aspergilloma, ABPA progressing to IPA etc.) in a single individual.

Case Report

A 58-year-old woman, resident of Bihar presented with a 4 years history of cough with expectoration, blood stained sputum on coughing, breathlessness on exertion associated with wheezing, frequent on and off episodes of fever and weight loss. She also gave history of repeated attacks of cold. She received anti-tuberculous therapy (ATT) for 9 months, prescribed on clinical and chest x-ray basis; but there was no improvement. Due to repeated attacks of haemoptysis, she was referred to our hospital for further management. She gave history of taking analgesics and steroids on and off for 20 years, for joint pains from local practitioners although Rheumatoid factor was negative. There was no other significant medical or surgical illness in the past. At the time of presentation, on clinical examination, bilateral wheeze was noted. Occasional crackles were heard on auscultation over chest bilaterally. Sputum direct smear and MGIT for Acid fast bacilli were negative. Chest X-ray showed patchy infiltrates, bronchiectatic changes, and cavities in both lungs. Sputum for AFB was negative. ELISA Test for HIV was negative. Blood examination in September 2015 showed leukocytosis with eosinophilia (TLC = 16220/mm³, DLC = N⁶⁶L²³M⁶E^4.7, AEC = 770/µL). Serum Total IgE was 393.31IU/mL (0-200 IU/mL). Specific IgE for Aspergillus fumigatus was negative but Serum precipitins for Aspergillus fumigatus were positive. Sputum fungal culture at the same time grew Aspergillus fumigatus. CECT Chest showed scattered cystic bronchiectatic lesions in bilateral lungs with mycetoma formation in few of them. Peripheral air crescent formation was also present [Figure 1-3]. Peripheral pruning of bronchovascular markings was seen suggestive of emphysematous changes. Subcutaneous skin prick test was also positive for A. fumigatus and A. tamari. PFT showed mild obstruction and restriction. A diagnosis of ABPA with chronic pulmonary aspergillosis with multiple aspergillomas was made fitting into Aspergillus Overlap Syndrome (AOS). She was treated symptomatically for haemoptysis and inhaled ICS was prescribed for breathlessness. Itraconazole 200mg BD was started and ICS was continued. Follow up sputum sample for fungal culture done after 2^nd and 4^th month showed growth of A. fumigatus. But after 6^th month, repeat sputum samples became sterile for fungal organisms indicating favorable response with azole therapy. Patient continued to have some episodes of fever and slight breathlessness and was treated symptomatically, but there was overall improvement in general condition. She gained weight and haemoptysis also abated. She was lost to follow up, but later revisited after a 10 month gap. She had continued the itraconazole. There was significant symptomatic improvement, and weight gain. Repeat blood counts showed normal TLC (8180/mm³) with DLC showing eosinophil 4.40% and AEC of 360/µL. Serum total IgE was 122 kUA/L. Repeat sputum cultures were negative for Aspergillus.

Discussion

Aspergillus is a ubiquitous fungal organism that causes a variety of pulmonary manifestations, both in immunocompetent and immunocompromised patients. It can vary from simple colonization, Aspergilloma, ABPA, to Chronic Pulmonary Aspergillosis (CPA) and Invasive Pulmonary Aspergillosis (IPA) (1).

Chronic Pulmonary Aspergillosis (CPA) was recognized as a clinical entity in 1842 (2). Several different terminologies and classifications have been proposed. Denning et al. (3) in 2003 proposed a classification dividing CPA into Chronic Necrotizing Pulmonary Aspergillosis (CNPA), Chronic Cavitary Pulmonary Aspergillosis (CCPA), and Chronic Fibrosing Pulmonary Aspergillosis (CFPA). The ERS and ESCMID now classify CPA into five entities: 1) Simple Aspergilloma, 2) CCPA, 3) CFPA, 4) Aspergillus nodule, and 5) Subacute Invasive Aspergillosis (previously CNPA) (4). 

The estimated global prevalence of CPA following pulmonary TB is 1.74 million, and ranges from 7 to 20% in ABPA cases (5). In India, the annual incidence of CPA is estimated to vary from 27, 000 cases to 1,70, 000 cases (6). 

The diagnostic criteria for CPA include a consistent appearance in thoracic imaging (preferably by CT), direct evidence of Aspergillus infection or an immunological response to Aspergillus spp., and exclusion of alternative diagnoses. In addition, the minimum duration of disease should be of 3 months and patients shouldn’t be immunocompromised. Immunological response usually indicates a positive Aspergillus IgG (4).

CCPA is the more common variety of CPA and is defined as one or more pulmonary cavities (with either a thin or/ thick wall) possibly containing one or more aspergillomas or irregular intraluminal material, with serological or microbiological evidence implicating Aspergillus spp., with significant pulmonary and/or systemic symptoms and overt radiological progression (new cavities, increasing peri-cavitary infiltrates or increasing fibrosis) over at least 3 months of observation (4).

The typical radiologic features of CCPA include unilateral or bilateral areas of consolidation associated with multiple expanding usually thick-walled cavities that may contain one or more aspergillomas. Cendrine et al. (7), in their study of 36 patients over 6 months found cavities in 32 (91.4%) patients which were unilateral in 21 (65.6%) and contained fungal ball in 20 (55.5%) patients. 

The term Pulmonary Aspergillus Overlap syndrome is used when two or three of the Aspergillus syndromes overlap (e.g., ABPA with Aspergilloma, ABPA progressing to IPA etc.). It has been reported in few case series and reports (8). Our patient had symptoms and radiological features suggestive of CCPA, along with positive serum precipitins for Aspergillus and Aspergillus fumigatus on sputum fungal cultures. Tuberculosis was ruled out with a negative culture. The presence of cystic bronchiectatic features and positive immediate skin prick test for A. fumigatus suggest ABPA. An Aspergillus overlap syndrome can be considered due to presence of features of ABPA with multiple aspergillomas and CCPA. The presence of multifocal pulmonary aspergillomas in CPA, seen in our patient, is a rare finding in itself (9). 

Various anti-fungals like itraconazole, voriconazole, posaconazole, micafungin, caspofungin and amphotericin B have all been employed in the treatment of CPA, with near similar outcomes (10). Itraconazole being cheap and easily available with fewer side effects, is commonly used. R. Aggarwal et al.^. (6) in their study on Indian patients with CCPA showed that itraconazole therapy was superior to conservative management. Oral triazole therapy is now considered the standard of care (4). 

In our patient, oral itraconazole therapy for 4 months rendered sputum sterile for Aspergillus. She did not require the use of oral long-term steroids. After 1 year of therapy patient showed significant clinical improvement and she remained stable for 2 years on follow-up.

Bharath Janapati DNB, Anil K Jain MD, and Priya Sharma DNB

Department of Respiratory Medicine

National Institute of Tuberculosis and Respiratory Diseases

New Delhi 110030, India

References

1. Grippi MA, Elias JA, Fishman J, Kotlof RM, Pack AI. (eds). Fishman’s Pulmonary Diseases and Disorders. 5th Edition. New York, NY: McGraw Hill. 2015.
2. Bennett J. On the parasitic vegetable structures found growing in living animals. Trans Royal Soc Edinburgh. 1842;15:277-9.
3. Denning DW, Riniotis K, Dobrashian R, Sambatakou H. Chronic cavitary and fibrosing pulmonary and pleural aspergillosis: case series, proposed nomenclature change, and review. Clin Infect Dis. 2003 Oct 1;37 Suppl 3:S265-80. [CrossRef] [PubMed]
4. Denning DW, Cadranel J, Beigelman-Aubry C, Ader F, Chakrabarti A, Blot S, Ullmann AJ, Dimopoulos G, Lange C; European Society for Clinical Microbiology and Infectious Diseases and European Respiratory Society. Chronic pulmonary aspergillosis: rationale and clinical guidelines for diagnosis and management. Eur Respir J. 2016 Jan;47(1):45-68. [CrossRef] [PubMed]
5. Denning DW, Pleuvry A, Cole DC. Global burden of allergic bronchopulmonary aspergillosis with asthma and its complication chronic pulmonary aspergillosis in adults. Med Mycol. 2013 May;51(4):361-70. [CrossRef] [PubMed].
6. Agarwal R, Denning DW, Chakrabarti A. Estimation of the burden of chronic and allergic pulmonary aspergillosis in India. PLoS One. 2014 Dec 5;9(12):e114745. [CrossRef] [PubMed]
7. Godet C, Laurent F, Bergeron A, et al. CT Imaging Assessment of Response to Treatment in Chronic Pulmonary Aspergillosis. Chest. 2016 Jul;150(1):139-47. [CrossRef] [PubMed]
8. Kousha M, Tadi R, Soubani AO. Pulmonary aspergillosis: a clinical review. Eur Respir Rev. 2011 Sep 1;20(121):156-74. [CrossRef] [PubMed]
9. Pendleton M, Denning DW. Multifocal pulmonary aspergillomas: case series and review. Ann N Y Acad Sci. 2012 Dec;1272:58-67. [CrossRef]  [PubMed]
10. Agarwal R, Vishwanath G, Aggarwal AN, Garg M, Gupta D, Chakrabarti A. Itraconazole in chronic cavitary pulmonary aspergillosis: a randomised controlled trial and systematic review of literature. Mycoses. 2013 Sep;56(5):559-70. [CrossRef] [PubMed]

Cite as: Janapati B, Jain AK, Sharma P. Medical Image of the Month: Pulmonary Aspergillus Overlap Syndrome Presenting with ABPA, Multiple Bilateral Aspergillomas. Southwest J Pulm Crit Care. 2021;22(3):76-80. doi: https://doi.org/10.13175/swjpcc002-21 PDF

Medical Image of the Month: Diffuse White Matter Microhemorrhages Secondary to SARS-CoV-2 (COVID-19) Infection

Figure 1.  An axial, maximal intensity projection (MIP), susceptibility weighted image (SWI) of the brain demonstrates numerous, punctate foci of susceptibility artifact in the genu (red arrow) and splenium of the corpus callosum (blue arrows). Other foci of susceptibility artifact are seen in the juxtacortical white matter (green arrows). These foci are consistent with microhemorrhages.

Clinical Scenario: A 59-year-old woman with hypothyroidism presented to the emergency room with progressive shortness of breath for 2 weeks.  Upon arrival, she was markedly hypoxic necessitating use of a non-rebreather to maintain her oxygen saturations above 88%. A chest radiograph demonstrated extensive, bilateral airspace disease. She was diagnosed with SARS-CoV-2 (COVID-19) pneumonia and started on the appropriate therapies. Approximately 48 hours into her hospitalization, she required intubation with mechanical ventilation due to her progressive hypoxemic respiratory failure.  She was intubated for approximately 5 weeks with a gradual improvement in her respiratory status, but not to the point where she was a candidate for a tracheostomy.  Despite being off sedation for an extended period, she remained unresponsive.  A CT of the head without contrast did not demonstrate any significant abnormalities.  An MRI of the brain was subsequently performed and demonstrated diffuse juxtacortical and callosal white matter microhemorrhages (Figure 1). Given her persistent encephalopathy and marked respiratory failure, her family elected to pursue comfort measures.

Discussion: In a recent retrospective analysis of brain MRI findings in patients with severe COVID-19 infections, 24% of the patients had extensive and isolated white matter microhemorrhages. White matter microhemorrhages with a predominant distribution in the juxtacortical white matter and corpus callosum are nonspecific and thought to be related to hypoxia.  Alternatively, small vessel vasculitis possibility related to a SARS-CoV-2 infection may result in this pattern of microhemorrhagic disease.  Diffuse axonal injury (DAI) is another etiology for microhemorrhagic disease distributed in the juxtacortical white matter and corpus callosum. However, DAI is secondary to a deceleration-type injury in the setting of trauma which is not present in most patients presenting with a SARS-CoV-2 infection. The prognosis of this condition remains to be determined.

Kelly Wickstrom, DO¹, Nicholas Blackstone MD², Afshin Sam MD¹, Tammer El-Aini MD¹

¹Banner University Medical Center – Tucson Campus, Department of Pulmonary and Critical Care, Tucson, AZ USA

²Banner University Medical Center – South Campus, Department of Internal Medicine, Tucson, AZ USA

References

1. Kremer S, Lersy F, de Sèze J, et al. Brain MRI Findings in Severe COVID-19: A Retrospective Observational Study. Radiology 2020: 297: E242-E251. [CrossRef] [PubMed]
2. Radmanesh A, Derman A, Lui Y et al. COVID-19-associated Diffuse Leukoencephalopathy and Microhemorrhages. Radiology. 2020 Oct;297(1):E223-E227. [CrossRef] [PubMed]

Cite as: Wickstrom K, Blackstone N, Sam A, El-Aini T. Medical Image of the Month: Diffuse White Matter Microhemorrhages Secondary to SARS-CoV-2 (COVID-19) Infection. Southwest J Pulm Crit Care. 2021;22(2):56-7. doi: https://doi.org/10.13175/swjpcc001-21 PDF

February 2021 Imaging Case of the Month: An Indeterminate Solitary Nodule

Prasad M. Panse MD

Clinton E. Jokerst MD

Michael B. Gotway MD

Department of Radiology

Mayo Clinic Arizona

Phoenix, Arizona 85054

Clinical History: A 43 -year-old woman with no past medical history presented to the Emergency Room with complaints of right chest wall pain extending into the right upper quadrant. The patient was a non-smoker, denied any allergies, and was not taking any prescription medications.

Physical examination showed the patient to be afebrile with normal heart and respiratory rates and blood pressure = 110/75 mmHg. Her room air oxygen saturation was 99%.

The patient’s complete blood count and serum chemistries showed normal values. Her liver function testing and renal function testing parameters were also within normal limits.

Which of the following represents an appropriate next step for the patient’s management?

1. Perform abdominal ultrasound
2. Perform chest radiography
3. Perform unenhanced chest CT
4. More than one of the above
5. None of the above

Cite as: Panse PM, Jokerst CE, Gotway MB. February 2021 Imaging Case of the Month: An Indeterminate Solitary Nodule. Southwest J Pulm Crit Care. 2020;21(5):41-55. doi: https://doi.org/10.13175/swjpcc006-21 PDF

Medical Image of the Month: Mucinous Adenocarcinoma of the Lung Mimicking Pneumonia

Figure 1. A contrasted, coronal-reformatted CT image of the chest demonstrates unilateral ground glass opacification of the right lung with superimposed interlobular septal thickening (blue arrows). There is also volume loss of the left lung with elevation of the left hemidiaphragm (red arrow).

Clinical Scenario: A 60-year-old man with a history of chronic obstructive pulmonary disease presented to the hospital with worsening shortness of breath over a period of 3 days. He had a 50-pack-year history of smoking, coronary artery disease, and a previous history of a left lung mass of unknown pathology status post left upper lobectomy. He was bought to the emergency room via ambulance after being found at home with oxygen saturations in the 60s. Upon arrival to the emergency room, he required continuous oxygen at 15 L/min to maintain his oxygen saturations above 88%. He had a progressive, markedly productive cough over the last few weeks prior to presentation. He had been treated for pneumonia with multiple courses of antibiotics over the last two months without any significant improvement. His blood work was significant for a leukocytosis with neutrophilia and an elevated D-dimer. He underwent a CTA of the chest in the emergency room to evaluate for a pulmonary embolism. The CTA of the chest had no evidence of pulmonary thromboembolic disease. However, there was unilateral ground glass opacification of the right lung with interlobular septal thickening along with volume loss of the left lung and associated elevation of the left hemidiaphragm (Figure 1). He was admitted to the medical ICU and started on broad-spectrum antibiotics. He underwent a bronchoscopy which demonstrated mucinous adenocarcinoma of the lung. His oxygen requirement was eventually weaned after multiple days in the ICU. He was discharged with follow up in the oncology clinic.

Discussion: Mucinous adenocarcinoma of the lung is the rarest type of adenocarcinoma of the lung. It is characterized as mucinous adenocarcinoma in situ, minimally invasive adenocarcinoma, and invasive mucinous adenocarcinoma. Mucinous adenocarcinoma of the lung is morphologically characterized by tall columnar cells with abundant cytoplasm that contain varying amounts of mucin. Mucus secreted by these cells can commonly be discharged as sputum. However, if airway obstruction occurs secondary to excessive mucus production, a post-obstructive pneumonia may develop. The prognosis of mucinous adenocarcinoma of the lung is poor.

Nicholas Blackstone MD¹, Tammer El-Aini MD²

¹Department of Internal Medicine and ²Department of Pulmonary and Critical Care, South Campus, Banner University Medical Center – Tucson, Tucson, AZ USA

References

1. Liu Y, Zhang HL, Mei JZ, Guo YW, Li RJ, Wei SD, Tian F, Yang L, Wang H. Primary mucinous adenocarcinoma of the lung: A case report and review of the literature. Oncol Lett. 2017 Sep;14(3):3701-3704. [CrossRef] [PubMed]
2. Marchetti A, Buttitta F, Pellegrini S, Chella A, Bertacca G, Filardo A, Tognoni V, Ferreli F, Signorini E, Angeletti CA, Bevilacqua G. Bronchioloalveolar lung carcinomas: K-ras mutations are constant events in the mucinous subtype. J Pathol. 1996 Jul;179(3):254-9. [CrossRef] [PubMed]
3. Travis WD, Brambilla E, Noguchi M, Nicholson AG, Geisinger KR, Yatabe Y, Beer DG, Powell CA, Riely GJ, Van Schil PE, Garg K, Austin JH, Asamura H, Rusch VW, Hirsch FR, Scagliotti G, Mitsudomi T, Huber RM, Ishikawa Y, Jett J, Sanchez-Cespedes M, Sculier JP, Takahashi T, Tsuboi M, Vansteenkiste J, Wistuba I, Yang PC, Aberle D, Brambilla C, Flieder D, Franklin W, Gazdar A, Gould M, Hasleton P, Henderson D, Johnson B, Johnson D, Kerr K, Kuriyama K, Lee JS, Miller VA, Petersen I, Roggli V, Rosell R, Saijo N, Thunnissen E, Tsao M, Yankelewitz D. International association for the study of lung cancer/American Thoracic Society/European Respiratory Society international multidisciplinary classification of lung adenocarcinoma. J Thorac Oncol. 2011 Feb;6(2):244-85. [CrossRef] [PubMed]
4. Cai D, Li H, Wang R, Li Y, Pan Y, Hu H, Zhang Y, Gong R, Pan B, Sun Y, Chen H. Comparison of clinical features, molecular alterations, and prognosis in morphological subgroups of lung invasive mucinous adenocarcinoma. Onco Targets Ther. 2014 Nov 18;7:2127-32. [CrossRef] [PubMed].
5. Xie GD, Liu YR, Jiang YZ, Shao ZM. Epidemiology and survival outcomes of mucinous adenocarcinomas: A SEER population-based study. Sci Rep. 2018 Apr 17;8(1):6117. [CrossRef] [PubMed]

Cite as: Blackstone N, El-Aini T. Medical image of the month: mucinous adenocarcinoma of the lung mimicking pneumonia. Southwest J Pulm Crit Care. 2021;22(1):8-10. doi: https://doi.org/10.13175/swjpcc072-20 PDF

Medical Image of the Month: Superior Vena Cava Syndrome

Figure 1. Large mediastinal lymph nodes (red arrow) causing compression of the superior vena cava (blue arrow). Numerous enlarged lymph nodes can also be seen in the axillary, cervical, and upper abdominal regions (green arrows).

History: A 74-year- old man with a history of diastolic heart failure, chronic kidney disease (CKD), and chronic lymphocytic leukemia (CLL) presented with a complaint of dyspnea. He has had several hospitalizations in the last year for heart failure exacerbation and his home bumetanide was recently increased from twice to three times daily due to persistently increasing weight. His CLL was diagnosed two years prior and treatment was stopped three months ago due to side effects. In the emergency department he reported three weeks of worsening dyspnea especially when lying flat, as well as increased swelling in his legs, abdomen, arms, and face. His weight was up to 277lbs from 238lbs the month before. His diuretics were transitioned to IV, but over the next few days he remained clinically volume overloaded. A noncontrast chest CT was obtained to help evaluate his ongoing respiratory distress (Figure 1). It demonstrated innumerable lymph nodes involving the cervical, axillary, mediastinal, and upper abdominal regions, which had significantly increased in size and number from prior exam several months before. The CT also showed several particularly bulky lymph nodes which appeared to be compressing the superior vena cava.

Discussion: The superior vena cava (SVC) is responsible for about one-third of the venous return to the heart. Because of its thin walls relative to arterial vasculature, it is susceptible to compression from adjacent structures which may subsequently impair venous return to the heart, a process known as SVC syndrome. Intrathoracic malignancy is responsible for 60-85% of cases of SVC syndrome, and common symptoms include facial or neck swelling, swelling of the arms, and dyspnea (1). In this case, the patient’s apparent resistance to diuresis was felt to be partially secondary to SVC syndrome. In stable patients, contrast-enhanced CT is the preferred imaging modality if SVC syndrome is suspected, which can define the extent of SVC blockage. Duplex ultrasound may be used first to exclude thrombus. In this patient with acute kidney injury on CKD it was decided to forgo the contrast study to avoid further kidney damage. Management of SVC syndrome depends on severity, with emergent treatment focused on maintaining the airway and endovenous recanalization. Definitive treatment is directed at the underlying cause (2).

After about a week of aggressive IV diuresis, the patient’s breathing and volume status improved and he was transitioned back to oral diuretics. He was discharged home with plans for hospice.

Matthew R. Borchart MD, Daniel Yu MD, and Indrajit Nandi MD

University of Arizona College of Medicine, Phoenix

Phoenix, AZ USA

References

1. Rice TW, Rodriguez RM, Light RW. The superior vena cava syndrome: clinical characteristics and evolving etiology. Medicine (Baltimore). 2006 Jan;85(1):37-42. [CrossRef] [PubMed]
2. Wilson LD, Detterbeck FC, Yahalom J. Clinical practice. Superior vena cava syndrome with malignant causes. N Engl J Med. 2007 May 3;356(18):1862-9. [CrossRef] [PubMed]

Cite as: Borchart MR, Yu D, Nandi I. Medical Image of the Month: Superior Vena Cava Syndrome. Southwest J Pulm Crit Care. 2020;21(6):136-7. doi: https://doi.org/10.13175/swjpcc060-20 PDF

Medical Image of the Month: Buffalo Chest Identified at the Time of Lung Nodule Biopsy

Figure 1. Buffalo chest, peripheral cavitary lesions, and pneumothorax contralateral to the biopsy site. A) Outpatient CT scan showing a right pneumothorax (blue arrow) and right-sided cavitary lesion (blue arrowhead). B) Subsequent pre-procedural planning CT scan done right lateral decubitus, showing again the cavitary lesion (blue arrowhead) but now with left pneumothorax (red arrow), suggesting buffalo chest. C) Intra-procedural CT showing needle at the periphery of the cavitary lesion (blue arrowhead) and similar-sized left pneumothorax (red arrow). D) 5-minute post-procedural CT demonstrating expected alveolar hemorrhage in the site of the biopsied cavitary lesion (blue arrowhead), but worsening left pneumothorax (red arrow). E & F) Multiple peripheral left lung cavitary lesions (red arrowheads) felt to be possible culprits for the worsened pneumothorax following coughing from the right-sided biopsy.

A gentleman in his late 50s with a past medical history of squamous cell carcinoma at the base of the tongue had numerous slowly-growing pneumocyst-like lesions despite clinical remission status post surgery and chemoradiation. Biopsy of one of these lesions was recommended by a multidisciplinary tumor board.

An outpatient pre-procedural supine chest CT revealed a right pneumothorax above the lesion targeted for biopsy. A subsequent pre-procedural right lateral decubitus chest CT three weeks later demonstrated a left-sided pneumothorax, raising concern for buffalo chest. (A less likely possibility would be spontaneous resolution of the right pneumothorax and development of a new left pneumothorax in the less than 4-week interval.) Intraprocedural imaging continued to demonstrate the left-sided pneumothorax. A biopsy touch preparation of the first sample obtained did not demonstrate malignancy. Therefore, an attempt was made at obtaining another sample. However, the patient developed a brief but forceful coughing fit, resulting in the termination of the procedure after only 2 passes of a 20g needle. Post-procedural scans demonstrated expected right-sided alveolar hemorrhage near the biopsy tract but slight worsening of the contralateral pneumothorax. The patient was again scanned five minutes later for concerns of a worsening pneumothorax. CT imaging demonstrated stable right-sided alveolar hemorrhage near the biopsy tract, but also severe left sided pneumothorax with multiple peripheral cavitary lesions. A left anterior chest tube was placed and the patient was discharged a few days later. Biopsy results showed granulomatous tissue only and cultures were negative.

Buffalo chest refers to the abnormal presence of a pleuro-pleural communication in humans. This phenomenon derives its name from the fact that buffalo and similar species possess one contiguous pleural space, while humans ordinarily have two independent pleural spaces corresponding to each lung (1). This pleuro-pleural communication can develop iatrogenically, congenitally, or as a result of trauma. Cases of buffalo chest developing after median sternotomy, laparoscopic surgery and heart-lung transplantation have been described in the literature (2). It is unknown if the worsening of our patient’s left-sided pneumothorax occurred in the setting of underlying buffalo chest, with biopsy producing a right sided pneumothorax that subsequently communicated with the left pleural space. Alternatively, our patient’s episode of forceful coughing could have increased the intrathoracic pressure and caused barotrauma to one of the many peripheral cavitary lesions previously described, leading to a worsening of the left-sided pneumothorax. Cases of bilateral pneumothoraces where interpleural connections exist have been successfully treated with a unilateral chest tube (2, 3). A second chest tube may be necessary in cases where the contralateral lung fails to re-expand. Our patient was able to be discharged after placement of a unilateral chest tube (contralateral to the biopsy side), reaffirming the general recommendation to treat pneumothoraces this patient population with a unilateral pleural catheter.

Phillip Belone MS4, Jason Lee MD, and Michael Craig Larson MD PhD

University of Arizona/Banner University Medical Center-Tucson

Department of Medical Imaging

Tucson, AZ USA

References

1. Jacobi A, Eber C, Weinberger A, Friedman SN. Bilateral Pneumothoraces after Unilateral Lung Biopsy. A Case of "Buffalo Chest"? Am J Respir Crit Care Med. 2016 Apr 15;193(8):e36. [CrossRef] [PubMed]
2. Sawalha L, Gibbons WJ. Iatrogenic "buffalo chest" bilateral pneumothoraces following unilateral transbronchial lung biopsies in a bilateral lung transplant recipient. Respir Med Case Rep. 2015 May 16;15:57-8. [CrossRef] [PubMed]
3. Groarke J, Breen D, O'Connell F, O'Donnell R. Bilateral pneumothorax resulting from a diagnostic thoracentesis. Eur Respir J. 2007 Nov;30(5):1018-9; diagnosis 1020. [CrossRef] [PubMed]

Cite as: Belone P, Lee J, Larson MC. Medical Image of the Month: Buffalo Chest Identified at the Time of Lung Nodule Biopsy. Southwest J Pulm Crit Care. 2020;21(5):121-3. doi: https://doi.org/10.13175/swjpcc056-20 PDF

November 2020 Imaging Case of the Month: Cause and Effect?

Prasad M. Panse MD 

Clinton E. Jokerst MD 

Michael B. Gotway MD 

Department of Radiology

Mayo Clinic, Arizona

Phoenix, Arizona USA

Clinical History: A 36 -year-old woman with Crohn’s disease and ulcerative colitis diagnosed approximately 1 year earlier, was initially treated with adalimumab, but later switched to prednisone and budesonide when subcutaneous nodules and migraines were attributed to this medication. Subsequently a flare of gastrointestinal symptoms prompted hospitalization with colonoscopy which showed severe pancolitis consistent with ulcerative colitis. One month following hospital discharge, the patient then presented to the Emergency Department with continued complaints of nausea, diarrhea, abdominal pain, intermittent fever (self-measured to 101º F), joint pain, and a pruritic rash all over her body. These symptoms had occurred following her hospitalization 2 months earlier. She also complained of 25 lbs. weight loss over the previous year.

In addition to prednisone and budesonide, the patient’s medications included hydroxyzine, famotidine, vitamin C, and hydrocodone-acetaminophen. The patient denies allergies and did not smoke nor use drugs.

Physical examination showed the patient to be afebrile with normal heart and respiratory rates and blood pressure = 112/75 mmHg. Her room air oxygen saturation was 99%. Her examination was remarkable for tenderness to palpation over the left > right lower quadrants with rebound tenderness and positive fecal occult blood testing. Her skin examination also showed a diffuse, pinpoint, maculopapular rash affecting her trunk as well as both the upper and lower extremities.

The patient’s complete blood count and serum chemistries showed hypokalemia=3.0 mmol/L (normal, 3.6-5.2 mmol/L), mild anemia (hemoglobin / hematocrit = 11.2 gm/dL / 34.3% [normal, 12.3-15.7 gm/dL / 37-46%]), and a minimally elevated lipase of 63 U/L (normal, 13-60 U/L). Liver and renal function testing were within normal limits.

Which of the following represents an appropriate next step for the patient’s management?

1. Obtain gastrointestinal consult
2. Obtain a travel history
3. Obtain abdominal CT
4. All of the above
5. None of the above

Cite as: Panse PM, Jokerst CE, Gotway MB. November 2020 Imaging Case of the Month: Cause and Effect? Southwest J Pulm Crit Care. 2020;21(5):108-120. doi: https://doi.org/10.13175/swjpcc058-20 PDF

Medical Image of the Month: Severe Left Ventricular Hypertrophy

Figure 1. An electrocardiogram demonstrates left ventricular hypertrophy by voltage and non-voltage criteria.

Figure 2. Parasternal long view of the heart demonstrates marked left ventricular hypertrophy with partial obstruction of the left ventricular outflow tract.

The patient is a 56-year-old man with a history of hypertension who was admitted to ICU after the administration of nitroglycerin for chest pain in the setting of hypertensive emergency resulted in a sudden drop in systolic BP drop from 220 to 106. The above images depict LVH on EKG (Figure 1) along with severe concentric LVH (End-diastolic-wall-thickness = 22mm) with significant apical and septal thickening resulting in partial obstruction of the left ventricle outflow tract concerning for HCM vs HHD (Figure 2).

Significant morphological overlap between HCM and HHD makes establishing a diagnosis difficult and often requires more advanced tissue characterization in the form of cardiac MR. In a patient with severe LVH, a diagnosis of HCM should be considered if ≥ 1 myocardial segment has a LV end-diastolic wall thickness (EDWT) ≥ 15mm on transthoracic echo¹. Additional features such as systolic anterior motion of the mitral valve (SAM) are also useful in establishing a diagnosis of HCM, especially in those with concomitant hypertension. A large majority of patients with HCM have elongated mitral valve leaflets which can protrude into the LV cavity. During systole, the mitral valve leaflet moves towards the interventricular septum which is thickened in patients with LVH. This creates a left ventricular outflow obstruction (LVOTO) that causes shortness of breath, chest pain, and syncope. This ultimately increases the risk of arrhythmias and sudden cardiac death.

Treatment of LVOT obstruction is indicated in all symptomatic patients. First line medical management functions to increase preload with negatively inotropic medications such as beta-blockers, disopyramide and verapamil. In patients who are persistently symptomatic despite optimal medical therapy, septal reduction therapy via alcohol septal ablation (ASA) or septal myomectomy (SM) are standard of care². Long-term data suggests there is no difference in cardiovascular mortality when comparing ASA and SM. However, those receiving ASA have lower periprocedural complications but more often require implantation of pacemakers or reintervention in the future.

April L. Olson MD MPH, Nicholas G. Blackstone MD, Benjamin J. Jarrett MD, and Janet M. Campion MD MPH

University of Arizona College of Medicine at South Campus

Tucson, AZ USA

References

1. Rodrigues JC, Rohan S, Ghosh Dastidar A, Harries I, Lawton CB, Ratcliffe LE, Burchell AE, Hart EC, Hamilton MC, Paton JF, Nightingale AK, Manghat NE. Hypertensive heart disease versus hypertrophic cardiomyopathy: multi-parametric cardiovascular magnetic resonance discriminators when end-diastolic wall thickness ≥ 15 mm. Eur Radiol. 2017 Mar;27(3):1125-1135. [CrossRef] [PubMed]
2. Osman M, Kheiri B, Osman K, Barbarawi M, Alhamoud H, Alqahtani F, Alkhouli M. Alcohol septal ablation vs myectomy for symptomatic hypertrophic obstructive cardiomyopathy: Systematic review and meta-analysis. Clin Cardiol. 2019 Jan;42(1):190-197. [CrossRef] [PubMed]

Cite as: Olson AL, Blackstone NG, Jarrett BJ, Campion JM. Medical Image of the Month: Severe Left Ventricular Hypertrophy. Southwest J Pulm Crit Care. 2020;21(4):80-1. doi: https://doi.org/10.13175/swjpcc052-20 PDF

Medical Image of the Month: Glioblastoma Multiforme

Figure 1. Non-contrast CT axial views of what was later identified as glioblastoma multiforme demonstrates heterogeneous left frontal lobe mass with foci of hemorrhage (black arrows, A), mass effect (gray arrow, A & B), central necrosis (gray arrowhead, C), invasion of the corpus callosum (gray arrowhead, C), and vasogenic edema (white arrow, D).

A patient in their 60's presented with headaches for approximately 2 weeks followed by acutely worsening mental status with confusion. CT of the head is shown (Figure 1). Glioblastoma multiforme was high on the differential diagnosis.

Glioblastoma multiforme (GBM) is classified as a grade IV astrocytoma and is the most common malignant primary brain tumor. It has an incidence of 3.19 cases per 100,000 persons per year. Astrocytomas are the most invasive type of glial tumor, directly reflecting the remarkably poor prognosis with a 5-year survival rate of approximately 4% and a 26-33% survival rate at 2 years in clinical trials. Symptoms develop relatively rapidly due to edema and mass effect of the tumor. Increased intracranial pressure and swelling manifests as nausea, vomiting, seizures and headaches that are typically worse in the morning. Neurological symptoms are dependent on the location of the cerebrum that is affected (ex. sensory, motor, visual changes, gait disturbances). Conventional gadolinium-enhanced MR imaging is the standard technique for the evaluation of GBM. GBM is characterized by a large, heterogeneous mass in the cerebral hemisphere exhibiting hemorrhage, necrosis and enhancement. In addition, magnetic resonance tomography (MRS) and positron emission tomography (PET) can be used to examine the chemical profile and assist in detecting tumor recurrence, respectively. The current gold standard treatment for GBM is temozolomide in combination with radiation therapy. Two potential new treatment modalities currently under investigation are gene therapy and immunotherapy.

Biopsy of the patient’s mass confirmed glioblastoma multiforme, which was successfully treated without recurrence on MRI 18 months later.

Cassandra Ann Roose and Michael Craig Larson MD, PhD

Medical Imaging Department

Banner University Medical Center/University of Arizona

Tucson, AZ UA

References

1. Stoyanov GS, Dzhenkov DL. On the Concepts and History of Glioblastoma Multiforme - Morphology, Genetics and Epigenetics. Folia Med (Plovdiv). 2018;60(1):48-66. [CrossRef] [PubMed]
2. Altman DA, Atkinson DS Jr, Brat DJ. Best cases from the AFIP: glioblastoma multiforme. Radiographics. 2007;27(3):883-888. [CrossRef] [PubMed]
3. American Association of Neurological Surgeons. Glioblastoma Multiforme. Available from: https://www.aans.org/en/Patients/Neurosurgical-Conditions-and-Treatments/Glioblastoma-Multiforme (accessed 8/24/20).

Cite as: Roose CA, Larson MC. Medical image of the month: glioblastoma multiforme. Southwest J Pulm Crit Care. 2020;21(3):64-5. doi: https://doi.org/10.13175/swjpcc046-20 PDF 

Medical Image of the Month and Brief Review: Aspiration Pneumonia in an Intubated Patient with COVID-19

 

Figure 1. Severe aspiration changes on CT. Bronchial wall thickening (white arrow) could barely be perceived elsewhere given the dense layering secretions (black arrows) in bilateral mainstem bronchi and filling the dependent segmental bronchi. Atelectatic collapse (black arrowhead) can be seen distal to the obstructed bronchi. Rounded consolidation (white arrowhead) as seen later in the course of SARS2 COVID-19.

A woman in her 60’s likely acquired COVID-19 through community transmission. When she developed respiratory distress, she came to the emergency department, was found to have abnormalities on chest x-ray and was intubated, testing positive on COVID-19 PCR. She developed worsening hypoxia over the course of one night after a fairly stable ICU course. CT was obtained and demonstrated severe aspiration changes including bronchial filling and collapse of the dependent lower lobes. Increased attention to suctioning helped with the desaturations, and she eventually recovered and was extubated. This case serves as a reminder to ensure adequate suctioning while patients are intubated to prevent aspiration, obstruction and related ventilator-associated pneumonia.

Discussion

Aspiration is a relatively common event which typically resolves with no clinical sequelae. In fact, recent studies have estimated that up to 50% of healthy adults aspirate while in their sleep (1). Pulmonary symptoms of aspiration generally only occur when there is compromise to the usual defenses that protect the lower airways (cough reflex, glottis closure, etc.) and when an inoculum is introduced which has a direct toxic effect on the lower airways, resulting in inflammation. Common predisposing conditions which can lead to aspiration include reduced consciousness (commonly seen in patients with alcohol abuse or IV drug use), dysphagia from neurologic deficits, disorders of the upper GI tract, or mechanical disruption of glottis closure due to endotracheal intubation, bronchoscopy, endoscopy, or NG feeding (2,3). Endotracheal intubation is a key risk factor in ventilator associated pneumonia (4). This brief review will focus on ventilator-associated pneumonia.

Overview and epidemiology: Ventilator-associated pneumonia is defined as new onset pneumonia at least 48 hours following intubation. Despite being frequently thought of as partially protective, the presence of an endotracheal tube may actually serve as a mechanism of transport of organisms from the oropharyngeal tract (most commonly) or GI tract (less commonly) to the lung (5,6). Recent data from 2012 to 2013 suggest that the percentage of patients on ventilator support who go on to acquire aspiration pneumonia is 9.7% (7).  Common pathogens associated with this condition include aerobic gram-negative bacilli (Escherichia coli, Klebsiella pneumoniae, Enterobacter spp, Pseudomonas aeruginosa, Acinetobacter spp) or gram-positive cocci including MRSA and Streptococcus Pneumoniae.

Prevention: Patients should be placed in the semi-recumbent position (45 degrees) and have intermittent (every 3-6 hours) or continuous subglottic drainage (8,9). Studies have found there isn’t a significant difference in clinical outcomes between intermittent and continuous drainage and that intermittent drainage may be associated with less adverse effects (10). The use of acid reducing agents should also be avoided, although sucralfate use decreased ICU-acquired pneumonia (11). Gastric volume monitoring had long been the standard of clinical practice with an aim to prevent vomiting and subsequent aspiration, however recent studies have suggested that gastric volume monitoring correlates poorly with aspiration risk and may lead to a decrease in caloric delivery (12,13).

Symptoms/Signs

• Important signs include fever, tachypnea, increased purulent secretions or hemoptysis; systemic signs including encephalopathy or sepsis may also be present (12).
• Ventilator: Reduced tidal volume, increased inspiratory pressures
• Labs: worsening hypoxemia, leukocytosis
• Imaging:
  • New or progressive infiltrates on CXR commonly with alveolar infiltrates or silhouetting of adjacent solid organs
  • Air bronchograms are common

Treatment

Empiric treatment choices should be guided by local distribution of pathogens and susceptibility of those pathogens to antimicrobials (14-16). Treatment options should also take into consideration the likelihood of MDR organisms or MRSA. In a meta-analysis of 15 studies, factors associated with an increased risk of MDR VAP were IV antibiotics in the last 90 days, >5 days of hospitalization prior to onset of symptoms, septic shock on presentation of VAP, ARDS before VAP, and renal replacement therapy prior to VAP. Risk factors for MRSA include treatment in units where >10 to 20% of S. Aureus isolates are methicillin resistant, treatment in a unit where prevalence of MRSA is not known, or prior history of MRSA infection. In the absence of risk factors for MDR or MRSA, patients with VAP should receive one agent that has activity against Pseudomonas, other gram-negative bacilli, and MSSA. Patients with risk factors for MDR or MRSA should receive two agents with activity against P. Aeruginosa and other gram-negative bacilli and one agent with activity against MRSA (15). An algorithm guiding specific regimens for treatment of VAP can be found on UpToDate’s article: Treatment of hospital-acquired and ventilator-associated pneumonia in adults (17).

Jeremy P. Head BS and Michael C. Larson MD

Department of Medical Imaging

University of Arizona

Tucson, AZ USA

References

1. Huxley EJ, Viroslav J, Gray WR, Pierce AK. Pharyngeal aspiration in normal adults and patients with depressed consciousness. Am J Med. 1978;64(4):564-568. [CrossRef] [PubMed]
2. Lo WL, Leu HB, Yang MC, Wang DH, Hsu ML. Dysphagia and risk of aspiration pneumonia: A nonrandomized, pair-matched cohort study. J Dent Sci. 2019;14(3):241-247. [CrossRef] [PubMed]
3. Mandell LA, Niederman MS. Aspiration Pneumonia. N Engl J Med. 2019;380(7):651-663. [CrossRef] [PubMed]
4. Rouzé A, Jaillette E, Nseir S. Relationship between microaspiration of gastric contents and ventilator-associated pneumonia. Ann Transl Med. 2018;6(21):428. [CrossRef] [PubMed]
5. Garrouste-Orgeas M, Chevret S, Arlet G, et al. Oropharyngeal or gastric colonization and nosocomial pneumonia in adult intensive care unit patients. A prospective study based on genomic DNA analysis. Am J Respir Crit Care Med. 1997;156(5):1647-1655. [CrossRef] [PubMed]
6. Jaillette E, Girault C, Brunin G, et al. Impact of tapered-cuff tracheal tube on microaspiration of gastric contents in intubated critically ill patients: a multicenter cluster-randomized cross-over controlled trial. Intensive Care Med. 2017;43(11):1562-1571. [CrossRef] [PubMed]
7. Metersky ML, Wang Y, Klompas M, Eckenrode S, Bakullari A, Eldridge N. Trend in Ventilator-Associated Pneumonia Rates Between 2005 and 2013. JAMA. 2016;316(22):2427-2429. [CrossRef] [PubMed]
8. Wang L, Li X, Yang Z, et al. Semi-recumbent position versus supine position for the prevention of ventilator-associated pneumonia in adults requiring mechanical ventilation. Cochrane Database Syst Rev. 2016;2016(1):CD009946. [CrossRef] [PubMed]
9. Caroff DA, Li L, Muscedere J, Klompas M. Subglottic Secretion Drainage and Objective Outcomes: A Systematic Review and Meta-Analysis. Crit Care Med. 2016;44(4):830-840. [CrossRef] [PubMed]
10. Mao Z, Gao L, Wang G, et al. Subglottic secretion suction for preventing ventilator-associated pneumonia: an updated meta-analysis and trial sequential analysis. Crit Care. 2016;20(1):353. Published 2016 Oct 28. [CrossRef] [PubMed]
11. Alquraini M, Alshamsi F, Møller MH, et al. Sucralfate versus histamine 2 receptor antagonists for stress ulcer prophylaxis in adult critically ill patients: A meta-analysis and trial sequential analysis of randomized trials. J Crit Care. 2017;40:21-30. [CrossRef] [PubMed]
12. Meduri GU. Diagnosis and differential diagnosis of ventilator-associated pneumonia. Clin Chest Med. 1995;16(1):61-93. [PubMed]
13. McClave SA, Lukan JK, Stefater JA, et al. Poor validity of residual volumes as a marker for risk of aspiration in critically ill patients. Crit Care Med. 2005;33(2):324-330. [CrossRef] [PubMed]
14. Kalil AC, Metersky ML, Klompas M, et al. Executive Summary: Management of Adults With Hospital-acquired and Ventilator-associated Pneumonia: 2016 Clinical Practice Guidelines by the Infectious Diseases Society of America and the American Thoracic Society [published correction appears in Clin Infect Dis. 2017 May 1;64(9):1298] [published correction appears in Clin Infect Dis. 2017 Oct 1;65(7):1251]. Clin Infect Dis. 2016;63(5):575-582. [CrossRef] [PubMed]
15. Beardsley JR, Williamson JC, Johnson JW, Ohl CA, Karchmer TB, Bowton DL. Using local microbiologic data to develop institution-specific guidelines for the treatment of hospital-acquired pneumonia. Chest. 2006;130(3):787-793. [CrossRef] [PubMed]
16. Jones RN. Microbial etiologies of hospital-acquired bacterial pneumonia and ventilator-associated bacterial pneumonia [published correction appears in Clin Infect Dis. 2010 Nov 1;51(9):1114]. Clin Infect Dis. 2010;51 Suppl 1:S81-S87. [CrossRef] [PubMed]
17. Klompas M. Treatment of hospital-acquired and ventilator-associated pneumonia in adults. UpToDate. July 31, 2020. Available at: https://www.uptodate.com/contents/treatment-of-hospital-acquired-and-ventilator-associated-pneumonia-in-adults (requires subscription).

Cite as: Head JP, Larson MC. Medical image of the month and brief review: aspiration pneumonia in an intubated patient with COVID-19. Southwest J Pulm Crit Care. 2020;21(2):35-8. doi: https://doi.org/10.13175/swjpcc040-20 PDF 

August 2020 Imaging Case of the Month: Piecing Together a Cause for Multisystem Abnormalities

Prasad M. Panse MD

Clinton E. Jokerst MD

Michael B. Gotway MD

Department of Radiology

Mayo Clinic Arizona

Scottsdale, AZ USA

Clinical History: A 65-year-old woman with chronic hoarseness and dyspnea now presents with complaints of diarrhea and bloating. The patient indicated her dyspnea had developed over the previous year, now occurring after one flight of stairs. The patient also complains of some substernal burning after waling 2-3 blocks. Her past medical history was largely unremarkable, and her past surgical history included only a cesarean section and carpal tunnel surgery. She has no allergies and her medications included thyroxine, fluoxetine, and a steroid inhaler. She was a previous smoker for 8 years, quitting 30 years ago. Upon directed questioning, the patient also complains of generalized weakness and 13-14 lbs. weight loss in the previous year.

Physical examination showed normal vital signs and was remarkable only for atrophy of the patient’s right calf muscles, which the patient claimed she knew about and had occurred over the previous year and a half. The neurologic examination was entirely normal. The examining physician noted that the patient’s tongue appeared somewhat enlarged and reddened, but was not coated and midline upon protrusion.

The patient’s complete blood count and serum chemistries showed all values within the normal range except for a serum albumin level of 2.9 gm/dL (normal, 3.5-5 gm/dL). Her erythrocyte sedimentation rate was mildly elevated at 55 mm/h (normal, 0-29 mm/hr). The patient was referred for chest radiography (Figure 1).

Figure 1. Frontal (A) and lateral (B) chest radiography.

Which of the following statements regarding the chest radiograph is most accurate? (Click on the correct answer to be directed to the second of nine pages)

1. The chest radiograph shows mediastinal and peribronchial lymph node enlargement
2. The chest radiograph shows multifocal basal consolidation
3. The chest radiograph shows normal findings
4. The chest radiograph shows numerous small nodules
5. The chest radiograph shows small bilateral pleural effusions

Cite as: Panse PM, Jokerst CE, Gotway MB. August 2020 imaging case of the month: piecing together a cause for multisystem abnormalities. Southwest J Pulm Crit Care. 2020;21(2):23-34. doi: https://doi.org/10.13175/swjpcc045-20 PDF 

Migratory Breast Implant: A Case Report and Brief Review

Bush Benjamin MD 

Nishal Brahmbhatt MD 

Jose F. Santacruz MD 

Ramchandani Mahesh MD

Houston Methodist Hospital

Houston, Texas USA

Abstract

A 75-year-old woman with a history of myasthenia gravis status post thymectomy and bilateral breast implants presented with complaints of acute onset shortness of breath and chest pain. Her thymectomy was performed via video-assisted thorascopic surgery (VATS) four months prior to presentation. A CT scan of the chest revealed migration of the left breast implant into the pleural space. She underwent an emergent thoracotomy with removal of the implant and subsequent complete resolution of her symptoms.

Introduction

We present a case of breast implant migration into the pleural space four months after video- assisted thoracoscopic surgery (VATS). A literature review highlights six other known cases of breast implant displacement following VATS. Breast augmentation is the number one cosmetic surgical procedure performed in the United States with the overall number of procedures rising from 2017 to 2018 (1). There are several complications that are associated with this surgical procedure. We present a rare case of breast implant migration into the pleural space after VATS. As the prevalence of breast implantation increases within the general population, thoracic surgeons and pulmonologists need to be aware of the risks of implant migration. Though rare, breast implant migration into the pleural space presents an important post-operative complication that will be explored in this case.

Case Summary

A 75-year-old woman presented to the emergency room with complaints of shortness of breath and left-sided chest pain. Her medical history was significant for chronic bronchiectasis on home oxygen, myasthenia gravis with intermittent exacerbations requiring IVIG and plasma exchange, and bilateral breast implants placed approximately 45 years earlier. Her myasthenia gravis was thought to be associated with a thymoma that was treated with thirty rounds of external beam radiation followed by a VATS thymectomy 4 months prior to presentation. Her thymectomy was well-tolerated with no immediate peri-operative complications. Two weeks post-thymectomy, she was hospitalized with complaints of shortness of breath. A CT scan of the chest revealed subacute appearing fractures of the anterior left 2^nd-5^th ribs, with interval widening of the anterior 4^th left rib interspace and increasing approximation of the left breast prosthesis to the left pleura which was believed to be secondary to her recent thymectomy (Figure 1). 

Figure 1. Axial contrast-enhanced CT of the chest shows approximation of the left breast prosthesis to the pleura.

These findings were not thought to be clinically significant and her symptoms were attributed to an exacerbation of her myasthenia gravis. Her symptoms resolved after treatment of an exacerbation of her myasthenia gravis. Two months later, she presented with acute onset of shortness of breath and left-sided chest pain which was new compared to prior symptoms. She also noted that her left breast implanted had moved. Subsequent physical exams noted no identifiable prosthesis along left anterior chest wall which prompted further evaluation. A CTA chest was obtained in the ED which identified interval migration of left breast implant into the posterior left chest (Figure 2). 

Figure 2. A: Coronal contrast-enhanced CT of the chest in lung windows performed two months later demonstrates migration of the breast prosthesis into the left pleural space with mass effect resulting in near complete collapse of the left lower lobe. B: Axial contrast-enhanced CT of the chest again demonstrates migration of the left breast prothesis into the left pleural space resulting in near complete collapse of the left lower lobe.

She was emergently taken to operating room for removal of the foreign body from pleural cavity. Prior to operation, the patient expressed her wish to forego further cosmetic operations and desired to simply have her implants removed. After repeat thoracotomy, the expulsed implant was removed. No post-operative complications were noted, symptoms resolved, and she was discharged home on post-op day 3 with continued outpatient monitoring.

Discussion

This case highlights a rare but potentially life-threatening complication of VATS procedures in the setting of a relatively common cosmetic procedure. Given the patient’s history of bronchiectasis and multiple hospitalizations for shortness of breath associated with her myasthenia gravis, her presentation could have initially been misidentified as a recurrent myasthenia gravis exacerbation. The astute observation by the patient of her implant migration is what prompted her physicians to further evaluate the etiology of her symptoms with imaging studies. Additionally, she underwent a VATS procedure for her thymectomy - a procedure generally performed to reduce the risk of complications, minimize recovery time, and for patients who may not tolerate open procedures. However, it should be documented that displacement of breast implants into the pleural space is a potentially severe, albeit rare, complication of VATS.

While pleural damage and potential expulsion of the breast prosthesis is a well-documented complication of breast augmentation, only a handful of cases of breast implant migration associated with VATS procedures have been reported. One case reported by Bruintjes et al. (2) details implant migration in the immediate post-operative period. Another case presented by Sykes et al. (3) reports intrathoracic migration of a breast implant approximately 5 months after a VATS procedure - a timeline similar to our case. Both cases noted small thoracic wall defects upon inspection, which in combination with the negative pressure of the pleural cavity, could account for migration of the breast implant into the pleural space. In our case, the CT surgeon noted a 15 cm left-sided thoracic wall defect communicating with the breast implant capsule during implant retrieval.

Migration of breast implants into the pleural space can cause lung collapse due to mass effect, promote the development of pleural effusions, cause localized inflammatory responses, and increase the risk of infections. Additionally, silicone breast implants have been noted to rupture and seed the pleural space - causing silicosis and scleroderma-like syndromes in women (4,5)

Additionally, the operative note revealed extensive fibrosis and scarring of mediastinal and anterior thoracic wall tissue consistent with her history of radiation therapy. The fibrotic tissue may have contributed to the patient’s presentation by causing delayed healing and a persistent defect in the thoracic wall which allowed for the displacement of the prosthesis. In this case, our patient had previous imaging that showed approximation of the left breast prosthesis to the pleura almost 2 months prior to this significant event. Intervention at that time or closer monitoring with repeat imaging could have potentially adverted this life-threatening event.

As minimally invasive procedures such as VATS are used more commonly and as the prevalence of breast augmentation increases, it is important to highlight the potential life-threatening complications that can arise in such patients. Physicians should consider such complications as to prevent delays in diagnosis and treatment.

References

1. ASPS National Clearing House of Plastic Surgery. Plastic Surgery Statistics Report 2018. Available at: https://www.plasticsurgery.org/documents/News/Statistics/2018/plastic-surgery-statistics-report-2018.pdf (accessed 7/13/20).
2. Bruintjes MH, Schouten C, Fabré J, van den Wildenberg FJ, Wijnberg DS. Where the PIP is the implant?. J Plast Reconstr Aesthet Surg. 2014;67(8):1148-1150. [CrossRef] [PubMed]
3. Sykes JB, Rosella PA. Intrathoracic migration of a silicone breast implant 5 months after video-assisted thoracoscopic surgery. J Comput Assist Tomogr. 2012;36(3):306-307. [CrossRef] [PubMed]
4. Gleeson JP, Redmond HP, O'Reilly S. Siliconosis and the long-term implications of silent breast implant rupture. Breast J. 2019;25(5):1002-1003. [CrossRef] [PubMed]
5. Wroński J, Bonek K, Stanisławska-Biernat E. Scleroderma-like syndrome in a woman with silicone breast implants - case report and critical review of the literature. Reumatologia. 2019;57(1):55-58. [CrossRef] [PubMed]

Cite as: Benjamin B, Brahmbhatt N, Santacruz SF, Mahesh R. Migratory breast implant: a case report and brief review. Southwest J Pulm Crit Care. 2020;21(1):11-14. doi: https://doi.org/10.13175/swjpcc039-20 PDF 

Medical Image of the Month: Diaphragmatic Eventration

Figure 1. An upright PA chest radiograph demonstrates marked elevation of the left hemidiaphragm with associated superior migration of the gas-filled colon and mild mediastinal shift towards the right.

Figure 2. A: frontal. B: sagittal. A non-contrasted reconstruction of the chest demonstrates marked elevation of the left hemidiaphragm with associated superior migration of the abdominal viscera along with preservation of the integrity of the hemidiaphragm. These findings are consistent with a left hemidiaphragm eventration.

Clinical Presentation: A 66-year-old woman presented with a three-year history of progressive postprandial dyspnea and left-sided abdominal pain.  Physical exam revealed normal vital signs and bowels sounds over left lung fields on auscultation. Laboratory work revealed a mild normocytic anemia.  Imaging demonstrated marked left hemidiaphragm elevation with ipsilateral lung parenchyma volume loss and atelectasis along with a mild contralateral mediastinal shift.  A sniff test was consistent with left hemidiaphragm paralysis.

The patient underwent a left video-assisted thoracoscopy, and the left hemidiaphragm was noted to be so thin that the abdominal organs could be visualize through it. The central tendon of the left hemidiaphragm was extremely attenuated and larger than normal. The left hemidiaphragm muscle fibers were noted to be situated around the periphery and not providing any significant tension. The redundant left hemidiaphragm central tendon was excised, and the patient was discharged without symptoms one week later.

Discussion: Eventration of a hemidiaphragm is a rare condition where there is non-paralytic weakening and thinning of a hemidiaphragm resulting in elevation of the hemidiaphragm with retained attachments to the costal margins (1). An eventration usually results from a congenital failure of the fetal diaphragm to muscularized. It is usually unilateral, occurs more on the right than the left, affects the anteromedial portion of the hemidiaphragm, occurs more often in women, and is found after the age of 60 in the adult population. A total eventration of a hemidiaphragm may be indistinguishable from diaphragmatic paralysis and result in a false-positive sniff test – as in this case. When symptomatic, it can pose a diagnostic challenge as it may be confused with a traumatic diaphragmatic rupture in the right clinical setting. Asymptomatic adults do not require treatment.

Leslie Littlefield MD and Mohamed Fayed MD

Department of Pulmonary and Critical Care

University of California San Francisco Fresno

Fresno, CA USA

Reference

1. Black MC, Joubert K, Seese L, et al. Innovative and Contemporary Interventions of Diaphragmatic Disorders. J Thorac Imaging. 2019;34(4):236-247. [CrossRef] [PubMed]

Cite as: Littlefield L, Fayed M. Medical image of the month: diaphragmatic eventration. Southwest J Pulm Crit Care. 2020;21(1):9-10. doi: https://doi.org/10.13175/swjpcc036-20 PDF 

Medical Image of the Month: Idiopathic Pulmonary Hemosiderosis

Figure 1. A-C: T1W 3D GRE post contrast multilevel axial images. D-F: CT axial images in a lung window (obtained three years before) both demonstrate innumerable centrilobular nodules consistent with the diagnosis of IPH.

The patient is a 36-year-old woman with a complex medical history including multiple venous thromboembolic events, miscarriages, heterozygous state for factor V Leiden deficiency, and Systemic Lupus Erythematosus. These images have been obtained during multiple admissions for shortness of breath during which she has been diagnosed with pulmonary embolism, anti-coagulation failure, pulmonary hypertension, and intracardiac right to left shunting. Images A-C are T1 weighted MRI axial sections showing centrilobular micronodules which are unchanged when compared to images D-F obtained during a CT scan of the chest three years prior. These findings are consistent with pulmonary hemosiderosis.

Idiopathic pulmonary hemosiderosis (IPH) is a rare condition that occurs with recurrent diffuse alveolar hemorrhage (1). Hemosiderin, a heme byproduct, gradually accumulates within the lung tissue, and can lead to fibrosis (2). IPH has a characteristic triad of hemoptysis, iron deficiency anemia, and pulmonary infiltrates on imaging (2) - although clinical presentation may be highly variable. The gold standard for diagnosis is lung biopsy, although bronchoalveolar lavage has 92% sensitivity of finding hemosiderin-laden macrophages in IPH (2). Classically, the disorder is found in children, but there have been more cases recorded in adults in recent years (3).

Radiographic findings: On chest x ray, areas of air-space consolidation or ground-glass opacities may be seen, usually with a perihilar or lower lung predominance. Consolidations typically clear within 3 days and are replaced by a reticular pattern (4). This may initially resolve but may progress to fibrosis after multiple occurrences - appearing as permanent reticulation or miliary stippling (1). On CT, the subacute phase demonstrates diffuse nodules and patchy areas of ground glass opacification. During an exacerbation, CT shows diffuse, homogenous areas of ground glass attenuation (4). On MRI, T1 images may show diffusely increased parenchymal signal intensity, whereas T2 images may show markedly reduced signal intensity due to the hemosiderin (4). The 3D gradient echo higher resolution MRI sequences in our patient, allowed for the recognition of the chronic micronodular pattern displayed.

Long term, low-dose, glucocorticoids are the main treatment for IPH, with immunosuppressants added on for severe cases. Tapering or reduction of glucocorticoids usually led to recurrence of pulmonary hemorrhage in patients (2). A large number of IPH cases coexist with Celiac disease (known as Lane-Hamilton Syndrome) and a gluten free diet may lead to remission (3).

On imaging, the differential diagnosis is broad, particularly if no remote imaging is available. In our patient’s case, the micronodular pattern may be seen with miliary infections, hypersensitivity pneumonitis, some forms of bronchiolitis (particularly smoking related or inhalational diseases). Microangiopathies are also to be considered, such as capillary hemangiomatosis.  IPH is a diagnosis of exclusion, and all other causes of diffuse alveolar hemorrhage must first be investigated, such as bronchiectasis, interstitial pneumonia, infections, connective tissue disease, coagulation disorders, systemic vasculitis, and/or anti-GBM disease (3).

Cynthia Ha, MS IV¹ and Diana Palacio, MD²

¹Lake Erie College of Osteopathic Medicine, Erie, PA

²Department of Medical Imaging, University of Arizona College of Medicine – Tucson, AZ

References

1. Repetto G, Lisboa C, Emparanza E, et al. Idiopathic pulmonary hemosiderosis. Clinical, radiological, and respiratory function studies. Pediatrics. 1967;40(1):24‐32. [PubMed]
2. Zhang Y, Luo F, Wang N, Song Y, Tao Y. Clinical characteristics and prognosis of idiopathic pulmonary hemosiderosis in pediatric patients. J Int Med Res. 2019;47(1):293‐302. [CrossRef] [PubMed]
3. Chen XY, Sun JM, Huang XJ. Idiopathic pulmonary hemosiderosis in adults: review of cases reported in the latest 15 years. Clin Respir J. 2017;11(6):677‐681. [CrossRef] [PubMed]
4. Primack SL, Miller RR, Müller NL. Diffuse pulmonary hemorrhage: clinical, pathologic, and imaging features. AJR Am J Roentgenol. 1995;164(2):295‐300. [CrossRef] [PubMed] 

Cite as: Ha C, Palacio D. Medical image of the month: idiopathic pulmonary hemosiderosis. Southwest J Pulm Crit Care. 2020;20(6):190-1. doi: https://doi.org/10.13175/swjpcc033-20 PDF 

Medical Image of the Month: Aspergilloma – Monod’s Sign

Figure 1 (A) Contrast-enhanced CT of chest showing irregular shape, thick wall cavity with oval heterogeneous soft tissue lesion (black arrow) at the posterior inferior aspect of this cavity. Figure 1 (B) Computed tomography of the chest in the prone position showing the mass moving to dependent region of the cavity (black arrow), known as Monod sign.

A 58-year-old man with a history of human immunodeficiency virus on antiretroviral therapy, bullous emphysematous lung with right upper lobe cavity presented with hemoptysis for three days. On presentation, he was afebrile, with normal oxygen saturation on room air and reduced bilateral breath sounds. Computed tomography (CT) of the chest showed a thick wall cavity at the right upper lobe, with a 3 cm heterogeneous mass at the posterior aspect of the cavity (Figure 1 A). When the patient was placed in the prone position, the soft tissue lesion displaced anteriorly (Figure 1B) showing gravity-dependency (Monod's sign). His serum Aspergillus fumigatus antibodies were also positive. The patient was diagnosed with aspergilloma and started on voriconazole initially. However, because of recurrent hemoptysis, the patient was scheduled to undergo surgical excision. Saprophytic aspergillosis is the causative organism for the development of an aspergilloma (1). It results from colonization of fungus in a preexisting pulmonary cavity which can lead to the formation of a fungus ball within the cavity (1,2). Hemoptysis is the most common presentation. CT scan should be performed in the supine as well as in the prone position to help differentiate from other conditions. In the case of recurrent or life-threatening hemoptysis, surgical excision remains the gold standard option (1).  

Kulothungan Gunasekaran MD, Nageshwari Palanisamy MBBS, Sandra Patrucco Reyes MD, Safal Shetty MD

Division of Pulmonary Diseases and Critical Care

Yale New Haven Health Bridgeport Hospital

Bridgeport, CT USA

References

1. Sharma S, Dubey S, Kumar N, Sundriyal D. 'Monod' and 'air crescent' sign in aspergilloma. BMJ Case Rep. 2013 Sep 13;2013:bcr2013200936. [CrossRef] [PubMed]
2. Grech R. Images in clinical medicine. Aspergilloma. N Engl J Med. 2010 Mar 18;362(11):1030. [CrossRef] [PubMed]

Cite as: Gunasekaran K, Palanisamy N, Patrucco Reyes S, Shetty S. Medical image of the month: aspergilloma – Monod’s sign. Southwest J Pulm Crit Care. 2020;20(6):188-9. doi: https://doi.org/10.13175/swjpcc032-20 PDF 

Medical Image of the Month: An “Intubation Box” to Protect Healthcare Professionals

Figure 1. A: Intubation box. B: Intubation box in use.

The COVID-19 pandemic has emerged as growing global healthcare crisis. There is evidence of transmission of the Severe Acute Respiratory Syndrome Coronavirus 2 (SARC-CoV-2) from aerosolized spread to personal protective equipment worn by healthcare professionals (1). In an attempt to mitigate hazards to healthcare professionals during the COVID-19 pandemic, particularly those at greater risk to exposure during endotracheal intubation, an Intubation Box has been designed by our Emergency Department (Figure 1A) (2). This is an inexpensive apparatus adjusted to include patients of large body habitus. We illustrate use of the box during endotracheal intubation using video laryngoscopy (Figure 1B). The box protects providers from aerosolized particulate and can be cleaned between each use with anti-viral reagents such as bleach-based or alcohol-based solutions. It is assembled in under one hour using acrylic with acrylic adhesive or equivalent plastic welding adhesive. Information on how to build this box in several easy steps, or how to order boxes, are provided for hospitals around the world at http://www.intubationbox.com.

Lavi Nissim MD¹ and Benjamin Reeser MD²

Departments of ¹Radiology and ²Emergency Medicine

Abrazo Central Campus

Phoenix, AZ USA

References

1. Ong SWX, Tan YK, Chia PY, Lee TH, Ng OT, Wong MSY, Marimuthu K. Air, Surface Environmental, and Personal Protective Equipment Contamination by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) From a Symptomatic Patient. JAMA. 2020 Mar 4. [Epub ahead of print] [CrossRef] [PubMed]
2. Cook TM. Personal protective equipment during the coronavirus disease (COVID) 2019 pandemic - a narrative review. Anaesthesia. 2020 Apr 4. [Epub ahead of print] [CrossRef] [PubMed]

Cite as: Nissim L, Reeser B. Medical image of the month: an “intubation box” to protect healthcare professionals. Southwest J Pulm Crit Care. 2020;20(5):173-4. doi: https://doi.org/10.13175/swjpcc030-20 PDF

Medical Image of the Month: Viral Pneumonias

Figure 1. Pulmonary viral infection spectrum on thoracic CT scan in lung windows: A= Coronavirus NL63; B= Adenovirus; C= Influenza AH1 2009; D= COVID-19; E= Coronavirus HKU1; F= Influenza AH1 2009.

Numerous viruses, including the corona, influenza and adenoviruses can cause lower respiratory tract infection in adults (1). Viral pneumonia in adults can be classified into two clinical groups: so-called atypical pneumonia in otherwise healthy hosts and viral pneumonia in immunocompromised hosts. Until the COVID-19 pandemic, influenza virus types A and B caused most cases of viral pneumonia in immunocompetent adults. Immunocompromised hosts are susceptible to pneumonias caused by a wide variety of viruses including cytomegalovirus, herpesviruses, measles virus, and adenovirus. The CT imaging findings consist mainly of patchy or diffuse ground-glass opacity, with or without consolidation, and reticular areas of increased opacity, are variable and overlapping. The imaging findings in COVID-19 pneumonia are generally not distinctive compared to other viral pneumonias, including other coronaviruses such as SARS and MERS (2). A recent study systematically reviewed the longitudinal changes of CT findings in COVID-19 pneumonia. The results suggested that the lung abnormalities increase quickly after the onset of symptoms, peak around 6-11 days, and are followed by persistence of the findings.

Bacterial pneumonias may also take multiple forms and are sometimes difficult to radiographically separate from viral pneumonia (3). However, the presence of ground-glass opacities alone is unusual for a bacterial pulmonary infection. Rather, bacterial infections commonly present as areas of consolidation with air bronchogram formation, centrilobular nodules (often with branching configurations) and airway thickening.

Michael B. Gotway MD

Department of Radiology

Mayo Clinic Arizona

Scottsdale, AZ USA

References

1. Kim EA, Lee KS, Primack SL, et al. Viral pneumonias in adults: radiologic and pathologic findings. Radiographics. 2002 Oct;22 Spec No:S137-49. [CrossRef] [PubMed]
2. Wang Y, Dong C, Hu Y, Li C, Ren Q, Zhang X, Shi H, Zhou M. Temporal Changes of CT Findings in 90 Patients with COVID-19 Pneumonia: A Longitudinal Study. Radiology. 2020 Mar 19:200843. [CrossRef] [PubMed]
3. Panse PM, Jokerst CE, Gotway MB. May 2020 Imaging Case of the Month: Still Another Emerging Cause for Infiltrative Lung Abnormalities. Southwest J Pulm Crit Care. 2020. May 1. (in press). [CrossRef]

Cite as: Gotway MB. Medical image of the month: viral pnuemonias. Southwest J Pulm Crit Care. 2022;20(5):163-4. doi:  https://doi.org/10.13175/swjpcc028-20 PDF 

May 2020 Imaging Case of the Month: Still Another Emerging Cause for Infiltrative Lung Abnormalities

Prasad M. Panse MD

Clinton E. Jokerst MD

Michael B. Gotway MD

Department of Radiology

Mayo Clinic, Arizona

Scottsdale, Arizona 85054

Clinical History: A 46-year-old man with a history of well-controlled asthma presented to the Emergency Room with complaints of worsening non-productive cough for 4-5 days followed by fever to 104°F over the previous 3 days. The patient also complained of some chills and loose stools. The patient denied rhinorrhea, sore throat, congestion, and nausea or vomiting. The patient also denied illicit drug use, and drinks alcohol only occasionally and denied smoking.

The patient’s physical examination showed a pulse rate of 79 / minute and a respiratory rate of 18 / minute, although his blood pressure was mildly elevated at 149/84 mmHg; he was afebrile with a temperature of 97.7 °F (36.5 °C). The patient’s room air oxygen saturation was 98%. The physical examination showed some mild expiratory wheezes bilaterally, but was otherwise entirely within normal limits.

Which of the following represents the most appropriate step for the patient’s management? (Click on the correct answer to be directed to the second of twelve pages)

1. Obtain a complete blood count
2. Obtain a travel history
3. Obtain serum chemistries
4. Perform chest radiography
5. All of the above

Cite as: Panse PM, Jokerst CE, Gotway MB. May 2020 imaging case of the month: still another emerging cause for infiltrative lung abnormalities. Southwest J Pulm Crit Care. 2020;20(5):147-62. doi: https://doi.org/10.13175/swjpcc027-20 PDF