Question
Dimorphic fungi are all except –
| A. |
Coccidioidomycosis |
| B. |
Blastomycosis |
| C. |
Candida |
| D. |
None |
|
Correct Answer » C Explanation |
 |
Clinical Reasoning for the Correct Answer:
– Coccidioides and Blastomyces are classic examples of dimorphic fungi (can exist as mold in the environment and yeast or yeast-like form in host tissues).
– Candida is NOT a dimorphic fungus in the classic sense; it usually exists as yeast and forms pseudohyphae or true hyphae under some conditions but does not exhibit temperature-dependent dimorphism like the others.
– “None” is incorrect because there IS a correct answer (i.e., Candida is not dimorphic).
Why Option A (Coccidioides) is incorrect:
– Coccidioides is a classic dimorphic fungus.
– In soil/environment (25°C): mold form; in tissue (37°C): spherules with endospores.
Why Option B (Blastomyces) is incorrect:
– Blastomyces is also dimorphic.
– In environment (25°C): mold; in tissue (37°C): broad-based budding yeast.
Why Option C (Candida) is correct:
– Candida is primarily a yeast but forms pseudohyphae or true hyphae under certain conditions.
– Lacks temperature-dependent true dimorphism seen in “systemic” dimorphic fungi.
– Common dimorphic fungi do NOT include Candida.
Why Option D (None) is incorrect:
– The stem asks which is NOT dimorphic; Candida fits this, so “None” is not correct.
