Comparison of Nikkomycin Z with Amphotericin B and Itraconazole for Treatment of Histoplasmosis in a Murine Model
AUTOR(ES)
Goldberg, Janet
FONTE
American Society for Microbiology
RESUMO
Nikkomycin Z was tested both in vitro and in vivo for efficacy against Histoplasma capsulatum. Twenty clinical isolates were tested for susceptibility to nikkomycin Z in comparison to amphotericin B and itraconazole. The median MIC was 8 μg/ml with a range of 4 to 64 μg/ml for nikkomycin Z, 0.56 μg/ml with a range of 0.5 to 1.0 μg/ml for amphotericin B, and ≤0.019 μg/ml for itraconazole. Primary studies were carried out by using a clinical isolate of H. capsulatum for which the MIC of nikkomycin Z was greater than or equal to 64 μg/ml. In survival experiments, mice treated with amphotericin B at 2.0 mg/kg/dose every other day (QOD) itraconazole at 75 mg/kg/dose twice daily (BID), and nikkomycin Z at 100 mg/kg/dose BID survived to day 14, while 70% of mice receiving nikkomycin Z at 20 mg/kg/dose BID and none of the mice receiving nikkomycin Z at 5 mg/kg/dose BID survived to day 14. All vehicle control mice died by day 12. Fungal burden was assessed on survivors. Mice treated with nikkomycin Z at 20 and 100 mg/kg/dose BID had significantly higher CFUs per gram of organ weight in quantitative cultures and higher levels of Histoplasma antigen in lung and spleen homogenates than mice treated with amphotericin B at 2.0 mg/kg/dose QOD or itraconazole at 75 mg/kg/dose BID. Studies also were carried out with a clinical isolate for which the MIC of nikkomycin Z was 4 μg/ml. All mice treated with amphotericin B at 2.0 mg/kg/dose QOD; itraconazole at 75 mg/kg/dose BID; and nikkomycin Z at 100, 20, and 5 mg/kg/dose BID survived until the end of the study at day 17 postinfection, while 30% of the untreated vehicle control mice survived. Fungal burden assessed on survivors showed similar levels of Histoplasma antigen in lung and spleen homogenates of mice treated with amphotericin B at 2.0 mg/kg/dose QOD; itraconazole at 75 mg/kg/dose BID; and nikkomycin Z at 100, 20, and 5 mg/kg/dose BID. The three surviving vehicle control mice had significantly higher antigen levels in lung and spleen than other groups (P < 0.05). The efficacy of nikkomycin Z at preventing mortality and reducing fungal burden correlates with in vitro susceptibility.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=89923Documentos Relacionados
- Efficacy of Nikkomycin Z in the Treatment of Murine Histoplasmosis
- Comparison of the Echinocandin Caspofungin with Amphotericin B for Treatment of Histoplasmosis following Pulmonary Challenge in a Murine Model
- Comparison of a New Triazole Antifungal Agent, Schering 56592, with Itraconazole and Amphotericin B for Treatment of Histoplasmosis in Immunocompetent Mice
- Comparison of a New Triazole, Posaconazole, with Itraconazole and Amphotericin B for Treatment of Histoplasmosis following Pulmonary Challenge in Immunocompromised Mice
- Clearance of Fungal Burden during Treatment of Disseminated Histoplasmosis with Liposomal Amphotericin B versus Itraconazole