Paracoccidioides brasiliensis

1. SYSTEMIC MYCOSES

2.  Histoplasma capsulatum
 Coccidioides immitis
 Blastomyces dermitis
 Paracoccidioides brasiliensis

3. Paracoccidioides brasiliensis
 is a dimorphic fungus
 cause Paracoccidioidomycosis
 formerly called South American blastomycosis

4. PATHOGENESIS
 Infection is acquired via lungs by inhalation of spores from
environmental sources.
 Most frequent in humid mountain forests of South and Central
America.
 Males are most frequently affected than females.Female
hormones probably protect the women.

5. EPIDEMIOLOGY
 1.Distribution: Disease is geographically restricted to
Central and South America with high incidence in Brazil,
Venezuela and Columbia.
 2.Reservoir: Fungus resides in a soil in an environment that
have high humidity.

6. Clinical disease
Pulmonary infection produce symptom initially. Fungus spread
from lung by haematogenous route to mucous membranes of
mouth and nose, lymph nodes and adjacent skin. Infection may
spread to adrenal gland,G.I tract and other viscera in fatal
cases.
 Primary pulmonary disease is often inapparent
 Ulcerative and chronic granulomatous disease of the buccal,
nasal, and gastrointestinal mucosa occur.

7. Laboratory diagnosis
 1.Direct examination:Microscopical examination in KOH
(10%) mount of specimen shows a large number of yeast cells
of P.brasiliensis of about 10–40 µm. Cells usually present as
single cells or chains of cells with characteristic multipolar
budding.
 2.Culture: In Sabouraud’s dextrose agar supplemented with
yeast extract and incubated at 25-30°C for 2 weeks shows
mycelial phase.
 3.Serological test:Immunodiffusion tests and CF test are
useful in diagnosis of 98% of cases.

8. A.Colonies of mycelial phase at 37°C B.Colonies of yeast at 37°C
C.Yeast cells in electron microscopy

9. Mycelium in electron microscopy

10. TREATMENT
 Sulphonamides
 Amphotericin B (1.5–2 g total dose, 30–90 days)
 The azoles (ketoconazole, fluconazole, itraconazole,
voriconazole and posaconazole).