Histopathological evaluation of the efficacy of antifungals for experimental Trichosporon bloodstream infection.

The efficacy of polyene macrolides to treat experimental Trichosporon bloodstream infection was evaluated by histopathological examination and viable cell counts in the kidneys of infected mice. Viable cell counts on the 5th day after infection confirmed that liposomal amphotericin B (L-AMB) is a more effective treatment than fluconazole (FLC) for mice infected with an azole-resistant strain of Trichosporon. Histological examination revealed that the administration of L-AMB induced a transformation from acute purulent inflammation caused by both azole-susceptible and -resistant strain infections to a chronic and subsiding form, whereas FLC failed to convert the acute inflammation induced by the azole-resistant strain to a subsiding form. Our results demonstrate that polyene macrolides can be used as an alternative therapy for infection of azole-resistant strains of Trichosporon and that histopathological evaluation is useful for elucidating the pathophysiology of an experimental Trichosporon infection.