SAN DIEGO—Low-dose fluconazole is safe and highly effective for antifungal prophylaxis after kidney transplantation, according to a study conducted by researchers at University of Utah Health Care in Salt Lake City.
The researchers, led by Magdalena Sikora, MD, a nephrology fellow, noted that antifungal prophylaxis is cumbersome because common antifungal agents are dosed three to four times daily. To improve patient adherence and decrease prescription costs, their center uses once-daily oral fluconazole 50 mg for four weeks.
Fluconazole inhibits the primary enzymatic pathway that metabolizes tacrolimus, the team explained. Elevated blood concentrations of tacrolimus have been reported with treatment doses of fluconazole, but whether low-dose fluconazole interacts with tacrolimus is unknown.
The study included 305 kidney transplant recipients who received the low-dose antifungal protocol. After three months of follow-up, fungal infections, which manifested as oral candidiasis, developed in only two patients (0.6%), Dr. Sikora reported at the 2010 American Transplant Congress.
The investigators also analyzed a subgroup of 103 patients who remained on a stable dose of tacrolimus one week before and one week after stopping fluconazole. While on and off fluconazole, patients had average trough levels of 11.69 and 11.15 ng/mL, respectively, a nonsignificant difference.
The high degree of efficacy demonstrated by low-dose fluconazole prophylaxis may be related to improved patient adherence engendered by once-daily dosing, although the study did not specifically examine this, the authors noted.