Paracoccidioidomycosis
Paracoccidioidomycosis is a dimorphic fungal infection endemic to Latin America, caused by Paracoccidioides species and identified by its distinctive multiple peripheral-budding "captain's wheel" yeast form on direct microscopy of pulmonary or mucocutaneous specimens. Presentation and treatment closely parallel blastomycosis: itraconazole for mild to moderate disease, liposomal amphotericin B for severe, disseminated, or CNS disease.
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What this article covers
- Overview
Paracoccidioidomycosis is a systemic infection caused by Paracoccidioides species, a dimorphic fungus endemic to Latin America (Central and South America).
- Epidemiology
Endemic to Latin America, with Central and South America identified as the geographic reservoir; disease occurs after exposure in or travel from these regions.
- Risk factors
Residence in or travel to an endemic area of Central or South America, the essential exposure risk for acquiring infection.
- Pathophysiology
Paracoccidioides is a dimorphic fungus: it exists as a mold at ambient environmental temperature (20°C) and converts to a yeast form at body temperature (37°C) once it infects a host, the same…
- Clinical features
Primary pulmonary infection, presenting as an inflammatory lung disease (acute or chronic pneumonia), is the initial and most common presentation, mirroring the pulmonary-first pattern of blastomycosis.
- Differential diagnosis
Blastomycosis: the closest mimic, with an identical clinical pattern (pulmonary primary infection, skin and bone dissemination) but a distinct endemic geography (Mississippi and Ohio River valleys)…
- Diagnosis
The diagnosis is confirmed by identifying the characteristic "captain's wheel" multiple peripheral-budding yeast form, much larger than a red blood cell, on direct microscopic examination of a…
- Management
First, for mild to moderate pulmonary or non-CNS disseminated disease, give itraconazole 200 mg PO once daily for 6 to 12 months, continuing until clinical, radiologic, and serologic criteria of cure…
- Complications
Dissemination to skin and bone, the extrapulmonary pattern described for this infection by direct analogy with blastomycosis.
- Prognosis
Mild to moderate disease treated with a full 6-to-12-month itraconazole course generally responds well, following the outcome pattern described for equivalent blastomycosis disease.
- Prevention
No vaccine exists; prevention relies on awareness of exposure risk when living in or traveling to an endemic area of Central or South America.
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