A patient, resident of Himachal Pradesh presented with a series of ulcers in a row, on his right leg. The biopsy from the affected area was taken and cultured on Sabouraud’s Dextrose agar. What would be the most likely causative organism ?
**Core Concept**
The patient's presentation of ulcers in a row on the leg is suggestive of a dermatophyte infection, which is a type of fungal infection that affects the skin, hair, and nails. Dermatophytes are a group of fungi that obtain their nutrients by breaking down keratin, a protein found in skin, hair, and nails.
**Why the Correct Answer is Right**
The biopsy from the affected area was cultured on Sabouraud's Dextrose agar, which is a type of agar that is specifically designed to promote the growth of fungi. The fact that the culture was done on this type of agar suggests that the causative organism is likely to be a dermatophyte. Dermatophytes are known to cause a condition called dermatophytosis, which can manifest as ulcers in a row, particularly in the legs. The most common dermatophytes that cause this condition are Trichophyton, Microsporum, and Epidermophyton species.
**Why Each Wrong Option is Incorrect**
**Option A:** This option is incorrect because it does not specify a dermatophyte, which is the most likely causative organism based on the patient's presentation and the culture method used.
**Option B:** This option is incorrect because it specifies a type of bacteria, which is unlikely to cause ulcers in a row on the leg.
**Option C:** This option is incorrect because it specifies a type of yeast, which is not typically associated with ulcers in a row on the leg.
**Clinical Pearl / High-Yield Fact**
Dermatophytes can be distinguished from other types of fungi by their ability to hydrolyze keratin, which is a key component of skin, hair, and nails.
**Correct Answer:** C. Epidermophyton floccosum.