Susceptibility to 5-fluorocytosine and prevalence of serotype in 402 Candida albicans isolates from the United States

作者：Robert L. Stiller, John E. Bennett, H.J. Scholer, Michael Wall, Annemarie Polak, David A. Stevens · 发表于：Antimicrobial Agents and Chemotherapy · 年份：1982 · DOI：10.1128/aac.22.3.482 · 被引用次数：105 · 研究领域：Antifungal resistance and susceptibility、Fungal Infections and Studies、Pneumocystis jirovecii pneumonia detection and treatment

Candida albicans isolates from 402 patients with no prior history of treatment with 5-fluorocytosine were collected at five medical centers from different areas of the United States. Isolates could be separated into four groups based on their minimum inhibitory concentrations (MICs) to 5-fluorocytosine. Group I isolates (60%) had MICs less than or equal to 12.5 micrograms/ml after 7 days, whereas groups II (22%), III (14%), and IV (4%) demonstrated MICs greater than 12.5 micrograms/ml on days 7, 2, and 1, respectively. Serotypes A and B accounted for 50.7 and 49.3%, respectively, of the 398 isolates typed. Serotype B was less prevalent in group I (26%), but predominated in the more resistant groups, groups II (85%), III (86%), and IV (53%). The common practice of identifying as "resistant" those isolates with MICs greater than 12.5 micrograms/ml after 48 h of incubation would yield a resistance rate in the United States of 11.5 to 15.5% in four centers and 35% in the fifth. Although serotype B and small agar disk diffusion zone sizes correlated with poor 5-fluorocytosine susceptibility, their ability to predict tube dilution MICs was limited. The true predictive value of such tests awaits correlation with in vivo studies.