Answer 40
Cryptococcal meningitis
False a. is caused only by Cryptococcus neoformans neoformans
True b. is more common than cryptococcal pneumonia
False c. characteristically causes leucopaenia
False d. only occurs in the immunosuppressed
False e. should be treated with ketoconazole
Cryptococcal meningitis is an indicator disease for AIDS. In the immunocompromised C.neoformans neoformans is the usual causal agent. Formerly in the tropics the gattii variant was more prevalent.
Pulmonary involvement may occur in upto one third of cases but primary pulmonary cryptococcal infection is 10 times less common.
In the immunocompetent, the white cell count is normal or raised.
Ketoconazole does not cross the blood brain barrier. Usually treatment is with intravenous amphoteracin B with or without flucytosine. In AIDS patients relapse is inevitable and lifelong prophylaxis with fluconazole or itraconazole is recommended. High dose fluconazole has been used successfully for treatment as an alternative to amphoteracin B.
The diagnosis is made by identifying the cryptococci in the cerebrospinal fluid by India ink staining. More sophisticated techniques can be used to detect cryptococcal antigen in the blood or cerebrospinal fluid.
The serum cryptococcal antigen titre has prognostic significance.