Reavaliação da suscetibilidade de Candida à anfotericina B: estudo comparativo com isolados de três hospitais do estado do Rio Grande do Sul

Susceptibility to amphotericin B was compared between isolates of Candida spp that were obtained from candidemia cases as follows: 41 from Hospital Universitario de Santa Maria, 56 from Hospital de Cl inicas, Porto Alegre, and 47 from the Santa Casa hospital complex, Porto Alegre. The tests were based on the document M27- A2 from the Clinical Laboratory Standards Institute, but with 20 concentrations of amphotericin B ranging from 0.1 to 2 mu g/ml. The tests were carried out using RPMI 1640 medium with glucose, antibiotic medium 3 and yeast nitrogen base- dextrose. The antibiotic medium 3 broth generated wide ranges of minimum inhibitory concentrations and minimum fungicidal concentrations in relation to the other agents. The variations in susceptibility between the hospitals were best detected in antibiotic medium 3. The isolates from Hospital Universitario de Santa Maria showed lower susceptibility than did those from the Santa Casa hospital complex, Porto Alegre ( p < 0.05). The causes of the susceptibility variations were not assessed but they indicate the need for surveillance regarding the susceptibility to amphotericin B.