Question

Black sclerotic bodies were observed on crust, cauliflowerlike foot lesions of a 30 year old male Indian patient from South America. Culture of the crushed black dots on SABHI agar revealed a slow-growing black, velvety colony. Microscopically, there was only the conidial arrangement see in Figure 6-36 (Picture 5).

What disease is suspected and why? Give two reasons

The etiologic agent is most likely:
-Cladosporium trichoides
-Fonsecaea pedrosoi
-Fonsecaea comapcta
-Exophiala jeanselmei
-Cladosporium carrionii

Answer 1

The suspected etiologic agent in the case of the patient is B. Fonsecaea pedrosoi.

Step-by-step explanation:

The disease suspected in the case of the 30-year-old male Indian patient with black sclerotic bodies on crust, cauliflower-like foot lesions is chromoblastomycosis caused by Fonsecaea pedrosoi. There are two main reasons for this suspicion. Firstly, the slow-growing black, velvety colony observed on SABHI agar is characteristic of Fonsecaea pedrosoi. Secondly, the conidial arrangement seen in Figure 6-36 also matches that of Fonsecaea pedrosoi.

Chromoblastomycosis is a chronic skin infection common in tropical and subtropical climates. It is caused by dematiaceous fungi, which produce pigmented conidia. The symptoms include the presence of black sclerotic bodies on the skin, which are the result of a granulomatous reaction to the fungus.

In conclusion, based on the clinical presentation, colony morphology, and microscopic appearance of the conidia, the etiologic agent most likely involved in this case is Fonsecaea pedrosoi, indicating a diagnosis of chromoblastomycosis. The correct answer is B. Fonsecaea pedrosoi,