Blood culture as a parameter of treatment effectiveness in experimental histoplasmosis of the hamster Hemocultivos como parametro de la eficacia del tratamiento de la histoplasmosis experimental en hamster

• Published in: Revista do Instituto de Medicina Tropical de São Paulo
• Main Authors: J. Finquelievich, M.R. Elías Costa, C. Iovannitti, R. Negroni
• Format: Article in Journal/Newspaper
• Language: English
• Published: Universidade de São Paulo (USP) 1995
• Subjects: Histoplasmosis; Blood culture; Experimental model; Azoles; Amphotericin B; Treatment; Arctic medicine. Tropical medicine; RC955-962; Infectious and parasitic diseases; RC109-216; Arctic
• Online Access: https://doi.org/10.1590/S0036-46651995000200002; https://doaj.org/article/33dd3f04589d496eae3bfc4e1750986e

The aim of this study was to determine the value of blood culture as a parameter of treatment effectiveness in experimental histoplasmosis. A total of thirty five hamsters, weighing approximately 120g, were inoculated intracardiacly with 0.1 ml of a suspension containing 4 x 10(7) cells/ml of the yeast phase of H. capsulatum. Treatments were started one week after the infection and lasted for 3 weeks. The azoles, (itraconazole, saperconazole and fluconazole) were administered once a day by gavage, at a dose of 8 mg/kg; Amphotericin B was given intraperitonealy every other day at a dose of 6mg/kg. Blood samples (1 ml) were obtained by heart punction from the 4th day after infection and were seeded in Sabouraud honey-agar and BHI-agar. The hamsters that survived were killed one week after treatment completion and the following criteria were considered for treatment evaluation: 1) rate of spontaneous death, at the end of the experience; 2) microscopic examination of Giemsa smears from liver and spleen and 3) determination of CFU in spleen cultures. Amphotericin B was the most effective drug, with negative blood cultures at day 20, negative spleen cultures in all cases and all the animals survived until the end of the study. Fluconazole was the less effective drug, blood cultures were positive during the whole experience, spleen cultures showed a similar average of CFU when compared with the control animals and 42.8% of these animals died. Saperconazole and itraconazole showed a similar activity, with survival of all hamsters and negative blood cultures at 23 and 26 days respectively. Blood culture seems to be valuable parameter for treatments' evaluation in experimental histoplasmosis of the hamster. El propósito de esta investigación fue determinar el valor de los hemocultivos para juzgar la eficacia de los tratamientos en la histoplasmosis experimental. Treinta y cinco hamsters fueron inoculados por via intracardíaca con 0.1 ml de una suspensión de la fase levaduriforme del H. capsulatum equivalente a 4 x 10(7) ...