Medical Image of the Week: Actinomycosis

Figure 1. Thoracic CT scan showing right-sided necrotizing pneumonia, lung abscess and empyema (arrows).

Figure 2. Cytospin and cell block of right lower lobe bronchoalveolar lavage fluid stained with Grocott-Gomori's (or Gömöri) methenamine silver (GMS) stain showing positive filamentous organisms consistent with Actinomyces species within a background of inflammatory cells.

Figure 3. Low (Panel A) and high power view (Panel B) of the lung showing alveolar septa filled with predominantly acute (neutrophilic) infiltrate.

A 55-year-old man with history of tobacco and alcohol abuse, presented with unresolving pneumonia despite treatment with moxifloxacin. It was thought to be possible coccidioidomycosis and an azole was started. However, he returned with increasing dyspnea and hypoxemia. He had leukocytosis with a thoracic CT revealing a loculated empyema, multifocal necrotizing infection and a large intrapulmonary abscess (Figure 1). He was admitted to MICU, intubated and ventilated. He was in septic shock requiring fluid resuscitation, vasopressors, and broad antibiotics. Bronchoscopy revealed erythematous and edematous airways, with drainage of over one liter of purulent fluid. A chest tube was placed to drain pleural fluid with removal of around two liters of blood-tinged, purulent fluid. His condition worsened with development of disseminated intravascular coagulation leading to hemorrhagic shock. He arrested and died. Gram stain on bronchoalveolar lavage fluid showed mixed gram negative and gram variable rods, and cultures grew lactobacillus species. GMS stain revealed filamentous organisms consistent with Actinomyces (Figure 2).

Necrotizing pneumonia is usually secondary to aspiration of oral bacterial flora, and is usually associated with severe sepsis and acute respiratory failure. The obstruction of the bronchus and blood vessels corresponding to a lung segment leads to decreased perfusion that is often shown on contrast enhanced CT scan. Hence, systemic antibiotic treatment alone is usually not effective. The management of necrotizing pneumonia is multidisciplinary; including adequate antibiotic therapy, mechanical ventilation, closed pleural drainage and supportive care. Despite the serious morbidity, massive parenchymal damage and prolonged hospitalizations, long-term outcome following necrotizing pneumonia is good with multidisciplinary care. If initial medical therapy fails, surgery is a reasonable option. Resection of gangrenous lung parenchyma and drainage of pleural empyema can lead to recovery in up to 80% of patients. Rarely, lobectomy can be a salvage operation. Outcome is affected by the severity of disease and underlying comorbidities. It should be considered once operative risk is acceptable.

Tauseef Afaq Siddiqi MD^1,2, Tracy Lundberg MD³, Jennifer Thorn MD³, and Dena L’heureux MD^1,2

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

²Department of Medicine, Southern Arizona Veterans Administration Health Sciences Center, Tucson, AZ

³Department of Pathology, The University of Arizona Medical Center, Tucson, AZ

References

1. Alifano M, Lorut C, Lefebvre A, Khattar L, Damotte D, Huchon G, Regnard JF, Rabbat A. Necrotizing pneumonia in adults: multidisciplinary management. Intensive Care Med. 2011;37(11):1888-9. [CrossRef] [PubMed]
2. Schweigert M, Dubecz A, Beron M, Ofner D, Stein HJ. Surgical Therapy for Necrotizing Pneumonia and Lung Gangrene. Thorac Cardiovasc Surg. 2013;61(7):636-41. [CrossRef] [PubMed]
3. Tsai YF, Ku YH. Necrotizing pneumonia: a rare complication of pneumonia requiring special consideration. Curr Opin Pulm Med. 2012;18(3):246-52. [CrossRef] [PubMed]

Reference as: Siddiqi TA, Lundberg T, Thorn J, L’heureux D. Medical image of the week: actinomycosis. Southwest J Pulm Crit Care. 2015;10(5):302-3. doi: http://dx.doi.org/10.13175/swjpcc050-15 PDF

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: Coccidioidomycosis

Figure 1. Preoperative x-ray (Panel A) demonstrating a right upper lobe cavitary lesion. X-ray (Panel B) status post lobectomy.

Figure 2. Coronal (Panel A) and axial (Panel B) images from a chest CT further demonstrating a right upper lobe cavitary lesion.

Figure 3. The 200x magnification H&E image (Panel A) demonstrates one of the numerous granulomas seen in the lung specimen. A low magnification (40x) (Panel B) H&E image showing the granulomatous infection, prominent at the left, surrounded by a wall made up of collagen.

Figure 4. Two images, both at 400x magnification, are of GMS stained tissue.  Panel A shows the numerous branching hyphae of the lesion.  Panel B shows a granuloma with a central Coccidioides spherule, marked by the red arrow.

A 41-year-old Hispanic man with a history of uncontrolled type 2 diabetes and coccidioidomycosis, presented to the emergency department with a two year history of hemoptysis and recent onset lower chest pain. Patient was found to have a right upper lobe cavitary lesion on x-ray (Figure 1). Due to concern for pulmonary and pericardial tuberculosis the patient was placed on isolation, and QuantiFERON Gold testing, Coccidioides antibodies and computed tomography of the chest were ordered. At this time the patient revealed that he had taken only 30 days of treatment for his coccidioidomycosis 2 years ago due to his understanding this was the complete course. The CT (Figure 2) demonstrated an irregular, spiculated, and thin-walled right apical cavitary lesion with satellite nodules. QuantiFERON Gold testing and Coccidioides testing were both positive. Surgical resection was performed due to ongoing hemoptysis. The surgical specimen demonstrated hyphae (Figure 4A), a rare spherule (Figure 4B) and caseating granulomas (Figure 3) consistent with coccidioidomycosis. Acid-fast stains were negative. Indications for surgery in coccidioidomycosis are continued or progressing symptoms following 3 months of treatment, complications (such as rupture, pneumothorax or effusion), and large size of abscess (1,2).

Kareem Hassan BA, Spencer Paulson MD, Carlos Tafich Rios MD

Departments of Medicine and Pathology

University of Arizona 

Tucson, AZ

References

1. Jaroszewski DE, Halabi WJ, Blair JE, et al. Surgery for pulmonary coccidioidomycosis: a 10-year experience. Ann Thorac Surg. 2009; 88:1765-72. [CrossRef] [PubMed]
2. Galgiani JN, Ampel NM, Blair JE, et al. Coccidioidomycosis. Clin Infect Dis. 2005;41: 1217-23. [CrossRef] [PubMed]

Reference as: Hassan K, Paulson S, Rios CT. Medical image of the week: coccidioidomycosis. Southwest J Pulm Crit Care. 2014;9(2):128-9 . doi: http://dx.doi.org/10.13175/swjpcc106-14 PDF