Combination antifungal chemotherapy for experimental disseminated candidiasis: lack of correlation between in vitro and in vivo observations with amphotericin B and rifampin.

Disseminated candidiasis was established in guinea pigs immunosuppressed with high-dose cortisone acetate. After the disease had been characterized by histopathologic study and quantitative culture of selected organs, guinea pigs were given amphotericin B alone or in combination with rifampin. The addition of rifampin to the regimen enhanced the in vitro rate of killing of the strain of Candida albicans used in the studies but was not noticeably beneficial in treatment of the disease in guinea pigs. Thus, the demonstration of an enhanced rate of killing in vitro was not a reliable basis for prediction of the response to the drug in vivo.