The incidence of fluconazole-resistant Candida spp. has increased in the last years. Investigation of alternative therapies for urinary tract infection (UTI) due to these microorganisms is necessary. Micafungin presents a minimal excretion in urine. However, it achieves high concentrations in plasma that could lead to high enough urine concentrations to reach optimal PK/PD ratios. The objective is to assess the clinical and microbiologic efficacy and the pharmacokinetics of micafungin in patients with UTI treated with this antifungal.
In a 3-year prospective study performed at a teaching 440-bed hospital, cases with symptomatic and microbiologically confirmed UTI due to fluconazole-resistant Candida spp. were included. Patients characteristics, microbiologic data and plasma and urine micafungin levels at steady state were collected. Micafungin concentrations were measured by a validated HPLC method. Cmax/MIC ratio of micafungin in plasma and urine was calculated. Following a previous report a rate Cmax/MIC greater than 4 for Candida spp. is correlated with clinical efficacy.
A total of 6 patients met the inclusion criteria. The following table shows clinical and microbiologial efficacy and pharmacokinetic characteristics.
Optimal micafungin CUrSS/MIC was achieved in almost all studied patients, with good clinical and microbiological response. This study provides evidence to support the use of micafungin for the treatment of UTI caused by fluconazole resistant Candida spp.
- ICAAC 55th (2015)