Molecular epidemiology and antifungal susceptibility of Cryptococcus neoformans isolates from Ugandan AIDS patients

Little is known of the antifungal susceptibility patterns and molecular epi demiology of Cryptococcus neoformans from tropical regions. We studied 164 clinical isolates of C. neoformans from 120 Ugandan? AIDS patients with cry ptococcal meningitis by analyzing their electrophoretic karyotypes and anti fungal susceptibility profiles. Computer-assisted analysis of karyotype pat terns was performed to generate dendrograms. MICs of fluconazole and flucyt osine were determined by reference methods. A total of 43 distinguishable D NA types were identified among the 164 isolates. Only 30 patients (25%) wer e infected with their own unique strain of C. neoformans, whereas 75% of th e patients shaved their infecting strain with at least one other patient. A mong 17 patients with more than one CSF isolate of C. neoformans, sequentia l isolates were identical Or highly related in 12 (71%) and were different in five patients (29%). The isolates were susceptible to both fluconazole a nd flucytosine and there were no instances in which a stepwise increase in either fluconazole or flucytosine MICs was observed among serial isolates. These findings suggest that the epidemiology of cryptococcal disease in AID S patients from tropical regions may be somewhat differ ent from that obser ved ill more temperate climates. (C) 1998 Elsevier Science Inc.