A 42-year-old man with AIDS (CD4 count 35 cells/μL) presents with progressive headache, fever (38.9°C), and blurred vision for 2 weeks. Vital signs show BP 118/76, HR 98, RR 16, SpO2 98% on room air. Lumbar puncture reveals opening pressure 32 cm H₂O with elevated protein (180 mg/dL) and normal glucose. India ink staining of cerebrospinal fluid demonstrates round budding yeast with thick polysaccharide capsule. No focal neurologic deficits noted. Which virulence factor most directly contributes to this organism's pathogenicity?
- A)Dimorphic growth in soil and tissue
- B)Production of diphtheria like exotoxin
- C)Antigenic variation of surface glycoproteins
- D)Polysaccharide capsuleGABARITO
- E)Actin based intracellular motility
Explicação
Cryptococcus neoformans is an encapsulated yeast that causes meningoencephalitis in immunocompromised patients. The thick polysaccharide capsule impairs phagocytosis and is an important virulence factor, which is why capsule based antigen tests are diagnostica... Ver explicação completa e trilha adaptativa →