A 50 year old farmer presents with warty lesion over left foot. Examination shows warts, cut nodules and florids of cauliflower. KOH mount shows yeast with dark brown irregular septae. Culture on Sabourauds agar shows sclerotic bodies. Probable diagnosis
**Core Concept**
The patient's presentation is consistent with a fungal infection, specifically a dermatophyte infection, characterized by warty lesions and the presence of a yeast with dark brown irregular septae in the KOH mount. The culture on Sabouraud's agar showing sclerotic bodies further supports this diagnosis.
**Why the Correct Answer is Right**
The patient's symptoms and laboratory findings are consistent with a diagnosis of **Phaeohyphomycosis**, a type of fungal infection caused by dematiaceous (pigmented) fungi. The presence of dark brown irregular septae in the KOH mount is a characteristic feature of these fungi. The culture on Sabouraud's agar showing sclerotic bodies is also consistent with this diagnosis. Sclerotic bodies are a type of fungal structure that is commonly seen in dematiaceous fungi.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is incorrect because the patient's symptoms and laboratory findings are not consistent with a diagnosis of **Candidiasis**, which typically presents with lesions on the mucous membranes or skin folds, and is not associated with the presence of sclerotic bodies.
* **Option B:** This option is incorrect because the patient's symptoms and laboratory findings are not consistent with a diagnosis of **Aspergillosis**, which typically presents with respiratory symptoms and is not associated with the presence of sclerotic bodies.
* **Option C:** This option is incorrect because the patient's symptoms and laboratory findings are not consistent with a diagnosis of **Histoplasmosis**, which typically presents with respiratory symptoms and is not associated with the presence of sclerotic bodies.
**Clinical Pearl / High-Yield Fact**
The presence of dark brown irregular septae in the KOH mount is a characteristic feature of dematiaceous fungi, which are a common cause of Phaeohyphomycosis. This is an important clinical correlation to remember when evaluating patients with skin lesions.
**Correct Answer:** C.