[Antimycotic drugs under continuous renal replacement therapy]

In critically ill patients with acute renal failure and continuous renal replacement therapy (CRRT), the elimination of antimycotic agents is influenced by many factors; these include not only the nature and dose of the renal replacement therapy but also the properties of the medicine. High protein binding, a high molecular weight and little or no renal elimination even in subjects with normal renal function suggest that a substance is not eliminated by CRRT. This is the case with amphotericin B, caspofungin, itraconazole and voriconazole, but not with fluconazole. In the case of fluconazole, an increase in dose than that used in patients with normal renal function may be required according to the nature and dose of CRRT, because the clearance of fluconazole can be substantially higher under CRRT than in subjects with normal renal function. Daily doses of 800 mg or more may be necessary. As a result of the diverse influences on elimination in patients receiving CRRT, the determination of fluconazole through concentrations cannot be dispensed with, in order to avoid underdosing and a failure of the antimycotic therapy.