Highlights & Basics
- Blastomycosis is an invasive infection caused by the dimorphic fungus Blastomyces dermatitidis, endemic to the north central and southern US, Canada, and parts of Africa.
- Most commonly involves the lungs. Dissemination can occur, with extrapulmonary infection often seen in the skin, bones, joints, central nervous system, and genitourinary system.
- Although key epidemiologic factors in the history are often suggestive of the diagnosis, histopathologic or microbiological examination of clinical specimens with demonstration of B dermatitidis is necessary to establish the diagnosis.
- First-line treatment for ambulatory patients is a prolonged course of oral itraconazole. Amphotericin-B is reserved for patients with more severe disease or for patients in whom itraconazole is contraindicated.
- No vaccine is available for disease prevention.
Quick Reference
History & Exam
Key Factors
Other Factors
Diagnostics Tests
Treatment Options
Definition
Epidemiology
Etiology
Pathophysiology
Images
Direct potassium hydroxide preparation at 40x magnification of a sputum specimen
Direct potassium hydroxide preparation at 20x magnification of a sputum specimen
Pulmonary blastomycosis with focal infiltrates on chest radiograph
Pulmonary blastomycosis presenting as a miliary pattern on chest radiograph
Cutaneous blastomycosis on the lower extremity
Cutaneous blastomycosis on the lower extremity
Axial T1 gadolinium-enhanced MRI image of cerebral blastomycosis
Cutaneous blastomycosis on the forearm
Cutaneous manifestation of disseminated blastomycosis
Close up of reticulonodular findings on chest radiography in disseminated blastomycosis
Citations
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Limper AH, Knox KS, Sarosi GA, et al. American Thoracic Society Fungal Working Group. An official American Thoracic Society statement: treatment of fungal infections in adult pulmonary and critical care patients. Am J Respir Crit Care Med. 2011 Jan 1;183(1):96-128.[Abstract]
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