Duration of fungal culture incubation in an area endemic for Histoplasma capsulatum.

To determine the optimum incubation period for recovery of fungi from clinical specimens in an area where Histoplasma capsulatum is endemic, we reviewed the results of 4259 consecutive fungal cultures. Of the total 1306 fungi isolated, 92.6% were detected by day 7, and 97.9% were detected by day 14. For the 1027 yeast isolates, only 1.4% were detected after day 7, none of which was considered clinically significant. Of the 281 mould isolates, 91.1% were detected by day 14; and of those detected after day 14, only isolates of H. capsulatum were considered clinically significant. An incubation protocol based on type of specimen is suggested.