Mycology · NEET PG Preparation Microbiology
A 30-year-old HIV-positive male presents with subacute meningitis. CSF analysis shows high opening pressure, low glucose, and high protein. India ink…
Practice question from Mycology (NEET PG Preparation Microbiology), with the correct answer and a step-by-step solution.
easy · MCQ · Q-0BCBA7
A 30-year-old HIV-positive male presents with subacute meningitis. CSF analysis shows high opening pressure, low glucose, and high protein. India ink preparation of the CSF reveals yeast cells with a prominent unstained halo. Which fungal structure constitutes the primary virulence factor responsible for the halo?
- A.Chitin cell wall
- B.Melanin pigment
- C.Glucuronoxylomannan capsuleCorrect answer
- D.beta-glucan layer
Solution
The organism is Cryptococcus neoformans. The unstained halo seen on India ink preparation represents its thick polysaccharide capsule, primarily composed of glucuronoxylomannan, which acts as a major virulence factor by inhibiting phagocytosis.
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