Resumo

TORRES, Joel  e  ROMERO, Hilda. Minimal infective dose of the mycelium phase of Histoplasma capsulatum var. capsulatum in Balb/c mice. Rev. Soc. Ven. Microbiol. [online]. 2011, vol.31, n.2, pp.144-148. ISSN 1315-2556.

The objective was to determine the Histoplasma capsulatum minimal infective dose (MID) by the inoculation of the mycelium phase in Balb/c mice, with the purpose of contributing useful alternatives for the future application of fungal inoculums which facilitate the reproduction of the disease. Several inoculums with 50, 75 and 94% transmittance (T) were prepared with a mixture of standardized suspensions from five isolations of the fungus, determining colony forming units/ml (CFU/mL) for each inoculum. Three groups of 10 mice each, identified as G2, G3 and G4, were injected intraperitoneally with 100 µl of each inoculum. Another group (G1) was included as healthy control. All mice were observed during 15 days. The disease was determined by observation of the animals, and by histopathological and mycological examinations. The MID was 50% T (17.5 x 10⁴ CFU/mL ) selected on basis of the presence of hepatosplenomegaly, nodules in liver and/or spleen, and the percentage of recovery of fungi from subcultures. The results showed the reproduction of the disease in absence of deaths during the 15-day observation period

Palavras-chave : Histoplasma capsulatum; histoplasmosis; minimal infective dose; experimental infection.