Question

A lady from West Rajasthan presented with an ulcer surrounded by erythema on the right leg. Microscopy of the biopsy from the edge of the ulcer showed organisms with dark staining nuclei and kinetoplast. What is the most likely causative agent?

• A. Leishmania tropica
• B. Babesia
• C. Trypanosoma
• D. Histoplasma

Answer 1

The Correct Option is A

The description provided points towards a cutaneous condition in a patient from West Rajasthan, where microscopy of a biopsy reveals organisms characterized by dark staining nuclei and kinetoplasts. These findings are relevant when identifying the causative agent of certain tropical diseases.

Let's evaluate the given clues:

• Geographic Area: West Rajasthan is known for its arid conditions, making it conducive to certain endemic diseases.
• Ulcer with Erythema: This can be associated with cutaneous leishmaniasis.
• Microscopy Findings: Presence of organisms with dark staining nuclei and kinetoplast indicates a parasitic infection typical to regions with tropical climates.

Now let's examine the options:

• Leishmania tropica: This protozoan parasite is known to cause cutaneous leishmaniasis, which fits the ulcer and erythema description. It is endemic in regions such as the Middle East and parts of India, including Rajasthan.
• Babesia: This is a genus of protozoan parasites that infects red blood cells and is transmitted by ticks, associated predominantly with babesiosis, not typical for the symptoms described.
• Trypanosoma: While this genus includes parasites causing diseases such as sleeping sickness and Chagas disease, the geographical context and ulcer characteristics do not match.
• Histoplasma: This is a fungal infection causing histoplasmosis, primarily affecting the lungs and not typically presenting with cutaneous ulcers and kinetoplast findings.

Given the geographical location, clinical presentation, and microscopic findings, the organism referred to is most likely Leishmania tropica. This aligns well with cutaneous leishmaniasis commonly found in Rajasthan.

In conclusion, the most likely causative agent of the described condition is Leishmania tropica.