CD4 LYMPHOCYTE COUNT IN HIV-POSITIVE PERSONS EXPOSED TO CRYPTOCOCCUS-NEOFORMANS

A report is presented on four HIV-positive homosexual men examined aft er several months of exposure during cleaning of a flat from masses of pigeon droppings heavily colonized by Cryptococcus neoformans. Only o ne out of the four persons, with a CD4 lymphocyte count of 50/mu L, fe ll sick from systemic cryptococcosis, but not the others, with CD4 lym phocyte counts of 180, 250, and 630/mu L, respectively; they remained clinically and mycologically inconspicuous and free from C. neoformans . Open questions in view of the epidemiology of opportunistic pathogen s in AIDS are discussed with regard to the CD4 cell count as a paramet er indicating a predisposition for cryptococcosis as an airborne AIDS- defining opportunistic infection. This has been confirmed by specific cultural diagnosis of the agent in both the environment and the patien t. Already in 1987/88, the probable source of infection had been the s ubject of epidemiological studies on C. neoformans in Berlin.