[Clinical fluconazole and itraconazole resistance of oro-gastrointestinal candidiasis in a patient with AIDS].

We report on a 32-year-old male patient with advanced acquired immunodeficiency syndrome (AIDS), who had severe candidiasis of the gastrointestinal tract. Treatment with fluconazole, 200 mg/day, was introduced. After oral intake of fluconazole over 5 months itraconazole 200 mg/day was given for 1 month. However, fungal infection still persisted. The antifungal activity of fluconazole, itraconazole and ketoconazole against Candida albicans was evaluated by means of the microdilution test by determining the 90% inhibitory concentration of each drugs. A high minimal inhibitory concentration (MIC) was detected for fluconazole (50 micrograms/ml) revealing fluconazole resistance. The susceptibility to itraconazole was borderline (MIC 0.125 micrograms/ml) and that to ketoconazole was markedly lowered (MIC 0.25 micrograms/ml). Plasma levels of itraconazole were also found to be lowered. In HIV patients the gastrointestinal absorption of azole derivatives is often reduced. Therefore, the clinical resistance of Candida albicans to itraconazole can be explained by reduced susceptibility after azole therapy and also by the decreased absorption of the drug in HIV patients.