Medical Image of the Week: Nocardiosis

Figure 1. Panel A: Thoracic CT scan showing enlarged left upper lobe mass. Panel B: CT scan from one month earlier showing a smaller lesion.

Figure 2. Panel A: GMS Silver stain showing Nocardia (200X magnification). Panel B: GMS silver stain showing Nocardia (400X magnification).

Figure 3. MRI Brain with arrows pointing to the lesion.

A 67 year-old man with advanced adenocarcinoma of the lung on chemotherapy and severe steroid dependent chronic obstructive pulmonary disease (COPD) was admitted for treatment of acute on chronic respiratory failure. He was admitted to the intensive care unit and required non-invasive positive pressure ventilation. He had a chest computed tomography scan (Figure 1A), with a left upper lobe mass, which was significantly larger than noted on a previous PET/CT scan (Figure 1B) from one month ago. He was placed on empiric broad-spectrum antibiotics and clinically improved. He underwent a transthoracic lung biopsy (Figure 2), which revealed the presence of organisms consistent with Nocardia on silver stain.  A brain MRI (Figure 3) showed the presence of a 4 mm enhancing lesion likely consistent with Nocardia.

Nocardiosis is a gram-positive bacterial infection caused by aerobic actinomycetes and is an important opportunistic pulmonary infection. It should be considered in the differential diagnosis of pulmonary infiltrates in immunosuppressed patients, including those with neoplasms, after organ transplantation, advanced HIV disease and those receiving chronic corticosteroid therapy or chemotherapy (1). Of importance to pulmonologists, in two reviews, COPD was a common underlying condition, representing over 20% of patients with Nocardiosis in these reports (2,3). Nocardia species are found in soil and infection is generally acquired through inhalation. The most common symptoms are fever, cough, pleuritic chest pain and headache. Common chest radiographic findings include consolidation, nodules, cavities and pleural effusions. Nocardia infections can disseminate to any organ but it has a predilection for spread to the central nervous system and patients with pulmonary Nocardia infections should have brain imaging to evaluate for cerebral dissemination. Antibiotics that are typically effective in Nocardia infections include trimethoprim-sulfamethoxazole (TMP-SMX), imipenim, amikacin, ceftriaxone and cefotaxime. However, antibiotic susceptibilities should be obtained and treatment tailored accordingly. It is recommended to treat severe systemic infections with two or three intravenous agents while awaiting susceptibility results. Treatment is usually prolonged because of the tendency of Nocardia infections to relapse or progress.  For patients with serious pulmonary infections and immunocompromised patients, duration of therapy is often at least 6 to 12 months or longer. Our patient was treated with TMP-SMX and meropenem and clinically improved. His steroids were rapidly tapered. Sputum cultures grew Nocardia farcinica.

Aarthi Ganesh MD, Muna Omar MD, James Knepler MD, and Linda Snyder MD

Department of Pulmonary and Critical Care

Banner University Medical Center

Tucson, AZ

References

1. Grigor LM, Hoover SE. Nocardiosis at a university medical center in the American southwest. Infect Dis Clin Pract 2014:22:279-82. [CrossRef]
2. Minero MV, Marín M, Cercenado E, Rabadán PM, Bouza E, Mu-oz P. Nocardiosis at the turn of the century. Medicine (Baltimore). 2009;88(4):250-61. [CrossRef] [PubMed]
3. Martínez Tomás R, Menéndez Villanueva R, Reyes Calzada S, Santos Durantez M, Vallés Tarazona JM, Modesto Alapont M, Gobernado Serrano M. Pulmonary nocardio-sis: risk factors and outcomes. Respirology. 2007;12(3):394-400. [CrossRef] [PubMed]

Reference as: Ganesh A, Omar M, Knepler J, Snyder L. Medical image of the week: nocardiosis. Southwest J Pulm Crit Care. 2015;10(5):220-2. doi: http://dx.doi.org/10.13175/swjpcc046-15 PDF

Medical Image of the Week: Wide Mediastinum Due to Lung Infiltrates

Figure 1. Panel A: Admission chest x-ray showing an apparent widened mediastinum. Panels B & C: CT scan showing consolidation in the posterior lungs bilaterally. Panel D: Chest x-ray showing resolution of his widened mediastinum with an increase in positive end-expiratory pressure.

The patient is a 65-year-old man patient with a past medical history of poorly controlled hypertension and coronary artery disease who was admitted after a witnessed code arrest. He was found down, and paramedics arrived within 5 minutes and started chest compressions. His initial CXR showed a wide mediastinum (Figure 1A) that was concerning for possible aortic dissection especially with his history of poorly controlled hypertension. Due to his hemodynamic instability a chest CT scan couldn’t be done initially, but the patient underwent a trans-esophageal echo that was negative for aortic dissection.

When the patient became more stable a chest CT scan with contrast was done and showed consolidation of the medial parts of both lungs with 7 bilateral rib fractures (Figure 1 B & C). The impression was either lung contusion from the aggressive chest compression as evidenced by the bilateral 7 rib fractures or aspiration in the dependent parts of the lung. His apparent widened mediastinum resolved with increasing the positive end-expiratory pressure (PEEP) on the ventilator within 48 hours (Figure 1D).

Huthayfa Ateeli MBBS, Laila Abu Zaid MD

Department of Medicine

University of Arizona

Tucson, AZ.

References

1. Cohn SM. Pulmonary contusion: review of the clinical entity. J Trauma. 1997;42(5):973-9. [CrossRef] [PubMed]
2. Lai CC, Wang CY, Lin HI, Wang JY. Pulmonary contusion associated with chest compressions. Resuscitation. 2010;81(1):133. [CrossRef] [PubMed]

Reference as: Ateeli H, Zaid LA. Medical image of the week: widen mediastinum due to lung infiltrates. Southwest J Pulm Crit Care. 2015;10(2):77-8. doi: http://dx.doi.org/10.13175/swjpcc007-15 PDF 

Medical Image of the Week: Killian-Jamieson Diverticulum

Figure 1. Chest x-ray showing worsening consolidation in both lungs.

Figure 2. Anterior (panel A) and lateral (panel B) fluoroscopic images showing retained contrast material in the anterior esophageal diverticulum in the hypopharynx.

An 89 year old female nursing home resident with a past medical history of hypertension and coronary artery disease was admitted with generalized weakness and vomiting for two days. Chest x-ray revealed consolidation in the left lung suggestive of pneumonia and she was started on broad spectrum antibiotics. Due to worsening consolidation in both lung fields (Figure 1) a video swallow was done for possible aspiration, which revealed contrast retained within the proximal esophagus within a diverticula in the anterior aspect (Figure 2). After excision of the diverticulum her pneumonia resolved and she was discharged back to the nursing home.

Killian-Jamieson diverticulum is a mucosal protrusion through a muscular gap in the anterolateral wall of the cervical esophagus; inferior to the cricopharyngeus and lateral to the longitudinal muscle of the esophagus just below its insertion on the posterior lamina of cricoid cartilage (gap also known as Killian-Jamieson space). This differentiates it from the Zenker’s diverticulum which arises from the muscular gap in the posterior portion of cricopharyngeus muscle (also known as Killian’s dehiscence). Killian-Jamieson diverticulum causes more non-specific symptoms than Zenker's diverticulum. Because these diverticula occur in close proximity to the recurrent laryngeal nerve, it should be carefully preserved during surgical resection.

Chandramohan Meenakshisundaram, MD and Nanditha Malakkla, MD

Medical Education

Saint Francis Hospital

Evanston, IL

References

1. Kim DC, Hwang JJ, Lee WS, Lee SA, Kim YH, Chee HK. Surgical treatment of killian-jamieson diverticulum. Korean J Thorac Cardiovasc Surg. 2012;45(4):272-4. [CrossRef] [PubMed]
2. Siddiq MA, Sood S, Strachan D. Pharyngeal pouch (Zenker's diverticulum). Postgrad Med J. 2001;77:506-11. [CrossRef] [PubMed]
3. Brant WE, Helms CA. Fundamentals of Diagnostic Radiology. Lippincott Williams & Wilkins. (2007) ISBN:0781765188

Reference as: Meenakshisundaram C, Malakkla N. Medical image of the week: killian-jamieson diverticulum. Southwest J Pulm Crit Care. 2014;9(5):287-8. doi: http://dx.doi.org/10.13175/swjpcc134-14 PDF

Medical Image Of The Week: Secondary Pneumonia Presenting as Hemoptysis

Figure 1. A-C: Axial images of the chest demonstrating bilateral consolidation of the lung with air bronchograms. D: Chest radiograph on presentation. E: BAL findings. F: Bronchoscopic images of diffuse airway sloughing; this is the main carina.

A 44 year-old man with a history of asthma presented to the hospital with encephalopathy, severe hypoxia and what was reported to be hematemesis. The patient was intubated in the Emergency Department and mechanical ventilation was instituted. Upper endoscopy was performed but source of bleeding could not be identified. Imaging of the chest showed pulmonary consolidation on both plain radiograph (D) and computed tomography (A-C). Bronchoscopy revealed a very friable mucosa with sloughing of the respiratory epithelium from the main carina (F) to at least the subsegmental level. Bronchoalveolar lavage (BAL) returned bloody fluid (E) but without any increase in blood with subsequent aliquots of fluid. The patient had progressively worsening hypoxia consistent with the acute respiratory distress syndrome (ARDS) requiring rescue maneuvers including paralysis, airway pressure release ventilation, and inhaled nitric oxide but we were unable to implement proning or transfer for extracorporeal life support due to profound cardiovascular collapse refractory to treatment. Ultimately, he succumbed from multiorgan failure. On laboratory evaluation of the BAL both Staphylococcus aureus and Influenza B virus were detected.

Bacterial pneumonia is a common complication of influenza infection. Historically, patients at the extremes of age have been most susceptible to secondary pneumonia. However, during the recent 2009 influenza pandemic an unusually high rate of secondary pneumonia among young adults was observed (1). The most common bacterial pathogens isolated following influenza infection include Staphylococcus aureus, Streptococcus pneumoniae, Streptococcus mitis, Streptococcus pyogenes and Haemophilus influenzae (2). A number of pathogenic mechanisms for synergies between influenza and bacteria have been proposed including disruption of the respiratory epithelium leading to enhanced bacterial adhesion (3).

Cameron Hypes MD MPH^1,2, Christian Bime MD MSc¹, Kevin Sun MD³, and Elizabeth Ulliman MD³

¹ Department of Medicine, Division of Pulmonary, Allergy, Critical Care, and Sleep Medicine, University of Arizona Medical Center; Tucson, AZ

² Department of Emergency Medicine, University of Arizona Medical Center; Tucson, AZ

³ Department of Medicine, University of Arizona Medical Center; Tucson, AZ

References

1. Chowell G, Bertozzi SM, Colchero MA, Lopez-Gatell H, Alpuche-Aranda C, Hernandez M, et al. Severe respiratory disease concurrent with the circulation of H1N1 influenza. New Engl J Med. 2009;361(7):674-9. [CrossRef] [PubMed]
2. Centers for Disease Control and Prevention (CDC). Bacterial coinfections in lung tissue specimens from fatal cases of 2009 pandemic influenza A (H1N1) - United States, May-August 2009. MMWR Morb Mortal Wkly Rep. 2009;58(38):1071-4. [PubMed]
3. Metersky ML, Masterton RG, Lode H, File Jr TM, Babinchak T. Epidemiology, microbiology, and treatment considerations for bacterial pneumonia complicating influenza. Int J Infect Dis. 2012;16(5):e321-e31. [CrossRef] [PubMed]

Reference as: Hypes C, Bime C, Sun K, Ulliman E. Medical image of the week: secondary pneumonia presenting as hemoptysis. Southwest J Pulm Crit Care. 2014;9(3):177-8. doi: http://dx.doi.org/10.13175/swjpcc116-14 PDF

Medical Image of the Week: Esophageal-Pleural Fistula

Figure 1. Esophagram showing fistulous tract formation from the distal esophagus just proximal to the gastroesophageal junction, with possible communication with the pleural space.

Figure 2. CT scan of the chest showed empyema with LLL pneumonia and air in the mediastinum.

Figure 3. Three- dimensional CT scan of the chest showed fistulous tract close to the gastroesophageal junction.

A 51 year old woman with rheumatoid arthritis, diabetes mellitus and gastroesophageal reflux disease had a transoral incisionless fundoplication for a hiatal hernia 6 months before admission. She presented with left lower lobe pneumonia and empyema. The esophagram showed a fistulous tract communicating with the pleural space (Figure 1). CT scan of the chest also showed air in the mediastinum (Figure 2) as well a fistulous tract in the three dimensional reconstruction (Figure 3). Esophagogastroduodenoscopy (EGD) showed an esophageal defect 5 cm above the gastroesophageal junction. An esophageal stent was placed with success.

Mohammed Alzoubaidi MD, Carmen Luraschi Monjagatta MD

Department of Pulmonary and Critical Care Medicine.

University of Arizona

Tucson, AZ

Referenc as: Alzoubaidi M, Luraschi-Monjagatta C. Medical image of the week: esophageal-pleural fistula. Southwest J Pulm Criti Care. 2014;8(3):179-80. doi: http://dx.doi.org/10.13175/swjpcc019-14 PDF

March 2014 Imaging Case of the Month

Michael B. Gotway, MD

Department of Radiology

Mayo Clinic Arizona

Scottsdale, AZ

Clinical History: A 60-year-old man with a history of severe asthmatic bronchitis presented with a 6 week history of intermittent fever, productive cough, shortness of breath, and decreased appetite. Four weeks earlier the patient was presumptively treated with amoxicillin for presumed community-acquired pneumonia, with some improvement, but his symptoms recurred 10 days following completion of his course of therapy. The patient also thought he was diagnosed with a COPD exacerbation during this time period and was treated with a short course of corticosteroids without improvement.

The patient was seen by his pulmonologist who noted decreased breath sounds over the right thorax, and referred the patient to the emergency room.

In the emergency room, a leukocytosis (white blood cell count = 17.4 x 10⁹ / L with neutrophilia) was noted. Broad-spectrum antibiotic coverage was re-instituted and frontal chest radiography (Figure 1) was performed.

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 move to the next panel)

1. The chest radiograph homogeneous complete right lung consolidation
2. The chest radiograph shows a right-sided mediastinal mass
3. The chest radiograph shows homogeneous right lung opacity suggesting right lung collapse
4. The chest radiograph shows homogeneous right lung opacity suggesting a large right pleural effusion
5. The chest radiograph shows multiple nodules

Reference as: Gotway MB. March 2014 imaging case of the month. Southwest J Pulm Crit Care. 2014:8(3):161-9. doi: http://dx.doi.org/10.13175/swjpcc015-14 PDF

Medical Image of the Week: Empyema

Figure 1. Admission thoracic CT showing a low density collection in the right lung likely from necrosis (*).

Figure 2. Selected views from the thoracic CT obtained 1 week after admission. Panel A: Architectural distortion (white circle) suggests necrotizing pneumonia. Note fluid within the bronchus intermedius (*). Panel B: Defect in visceral pleura (arrow) with decompression of parenchymal necrosis into the pleural space.  Note enhancement and thickening of both pleural layers. Panel C: Defect in parietal pleura (black arrow) with fluid extending into the extrapleural space. Pericardial effusion (*), new left pleural effusion and left parietal pleura enhancement (white arrow) suggests spread of infection. Incidental hiatal hernia (+).

A 71 year-old man with chronic obstructive pulmonary disease (COPD) presents to the emergency department complaining of dyspnea after recent admission for pneumonia. Chest CT shows a low density collection in the right lung suggesting necrosis (Figure 1). A CT obtained 1 week after admission (Figure 2) shows progression to empyema.

Management of empyema can be difficult. If the fluid cannot be removed with a therapeutic thoracentesis, a chest tube should be inserted and consideration be given to the intrapleural instillation of fibrinolytics (1). If the loculated effusion persists, the patient should be subjected to video-assisted thoracoscopic surgery. If the lung cannot be expanded with this procedure, a full thoracotomy with decortication should be performed. The definitive procedure should be performed within fourteen days.

Jason R. Young MD and David L. August, MD

Department of Radiology

Maricopa Integrated Health System

Phoenix, AZ

Reference

1. Light RW. Parapneumonic effusions and empyema. Proc Am Thorac Soc. 2006;3(1):75-80. [CrossRef] [PubMed]

Reference as: Young JR, August DL. Medical image of the week: empyema. Southwest J Pulm Crit Care. 2013;7(5):300-1. http://dx.doi.org/10.13175/swjpcc143-13 PDF

Medical Image of the Week: Cytomegalovirus Pneumonia

Figure 1. CT Chest, coronal cut showing left lower lobe consolidation.

Figure 2.  Pap stain highlights an enlarged cytomegalovirus-infected pneumocyte containing a single, dark intranuclear inclusion (arrow) with surrounding halo, giving the cell a characteristic “owl’s eye” appearance. Background cells consist of predominantly of macrophages and red blood cells (100x).

Figure 3. CMV-infected pneumocyte demonstrating an enlarged nucleus with a single dense intranuclear inclusion. The cytoplasm contains smaller basophilic inclusions with vacuolization and cytoplasmic projections (Pap stain, 100x).

A 29 year-old female with a history of systemic lupus erythematosus presented with a seven-day history of fever, dyspnea and a non-productive cough. She underwent renal transplantation four weeks prior to admission and was maintained on mycophenolate, tacrolimus, prednisone and prophylactic fluconazole, trimethoprim/sulfamethoxazole and valgangcyclovir. A CT chest was performed (Figure 1) and revealed left lower lobe consolidation. A BAL was performed in the left lower lobe and the cell count revealed 50% lymphocytes, 13% neutrophils and 37% macrophages. The BAL Papanicolaou stain showed enlarged cytomegalovirus-infected pneumocytes with the characteristic “owl’s eye” appearance (Figures 2 and 3). CMV quantitative PCR from serum resulted 648,615 IU/m.  The BAL culture grew CMV. The patient was started on treatment with valgangcyclovir with clinical improvement.

While often thought of as a “pneumonitis” with diffuse infiltrates, CMV can cause a lobar pneumonia in up to 30% of patients.  Prophylaxis is effective, but cases can occur despite a preemptive strategy.

Nathaniel Reyes MD^*, Julianna J. Weiel MSII⁺, Erika R. Bracamonte MD⁺, Linda Snyder MD^*
Department of Medicine, Division of Pulmonary and Critical Care Medicine*
Department of Pathology⁺

University of Arizona

Tucson, Arizona

Reference

Kang E, Patz E, Miller NL. Cytomegalovirus pneumonia in transplant patients: CT findings. J Comput Assisted Tomogr. 1998:20:295-9. [CrossRef]

Reference as: Reyes N, Weiel JJ, Bracamonte ER, Snyder L. Medical image of the week: cytomegalovirus pneumonia. Southwest J Pulm Crit Care. 2013;7(4):221-2. doi: http://dx.doi.org/10.13175/swjpcc131-13 PDF

April 2012 Imaging Case of the Month

Michael B. Gotway, MD

Associate Editor, Imaging

Clinical History: A 31-year-old previously healthy, immunocompetent, non-smoking female developed cough and was initially treated with broad spectrum antibiotics without improvement. Approximately 48 hours later, the patient presented to her physician with progressive shortness of breath and fever to 103°F. A chest radiograph was performed (Figure 1).

Figure 1: Frontal chest radiograph shows extensive bilateral pulmonary opacities predominantly in the lower lobes with preserved lung volumes, normal mediastinal width, and no definite pleural effusion.

The differential diagnostic considerations for the appearance on the chest radiograph include which of the following?

1. Hydrostatic pulmonary edema
2. Acute hypersensitivity pneumonitis
3. Community-acquired pneumonia
4. Opportunistic pulmonary infection
5. All of the above

Reference as: Gotway MB. April 2012 imaging case of the month. Southwest J Pulm Crit Care 2012;4:102-10. (Click here for a PDF version)