Methodologic problems in the biotyping of Candida albicans

The biotyping of 284 C. albicans strains has been carried out in accordance with the system of three tests, proposed by F.C. Odds and A. B. Abbott. The reliability of the epidemiological conclusions made as the result of this work has been analyzed. The independence of the signs of C. albicans used in biotyping and the asymmetrical character of the test for its sensitivity to 5-fluorocytosine have been shown. The change of this test for a more symmetrical one is proposed. The study has shown that in the process of prolonged storage with periodic subculturing the proportion of C. albicans strains resistant to pH 1.40 and possessing proteolytic activity is decreased. The distribution of different biotypes among C. albicans strains isolated from candidiasis patients and from carriers has proved to be the same.