Efficacy of escalating doses of liposomal amphotericin B (AmBisome) against hematogenous Candida lusitaniae and Candida krusei infection in neutropenic mice.

Immunosuppressed CF1 mice were infected intravenously with two strains of Candida krusei and four strains of Candida lusitaniae (two of which were resistant to amphotericin B). Mice were treated with 1 or 2 mg of amphotericin B desoxycholate per kg of body weight per day or escalating doses of liposomal amphotericin B (8 to 30 mg/kg/day) or were left untreated. Higher doses of liposomal amphotericin B were as effective as standard dose of amphotericin B desoxycholate in prolonging survival but were significantly more effective in reducing the fungal burden in the kidneys of animals infected with both C. krusei strains and the C. lusitaniae strains that were susceptible to amphotericin B desoxycholate. This advantage of liposomal amphotericin B therapy could not be demonstrated in mice infected with the C. lusitaniae strains that were resistant to amphotericin B desoxycholate.