Original article: Fungemia by yeasts in Brazil: occurrence and phenotypic study of strains isolated at the Public Hospital, Botucatu, Sao Paulo

• Published in: Journal de mycologie médicale Vol. 15; no. 1; pp. 13 - 21
• Main Authors: Ruiz, L S, Sugizaki, M F, Montelli, A C, Matsumoto, F E, Pires, M F C, Da Silva, B C M, Silva, E H, Gandra, R F, da Silva, E Goncalves, Auler, M E, Paula, C R
• Format: Journal Article
• Language: English
• Published: 01.03.2005
• Subjects: Candida albicans
• ISSN: 1156-5233
• DOI: 10.1016/j.mycmed.2004.12.002

Objective. - In this study strains of yeasts isolated from the blood of human patients were analyzed taxonomically, their virulence factors were determined and compared, and phenotypic markers were used to compare the samples with respect to phenotypic differences across the range of patients as well as between samples isolated from the same patient. Methods. - The study involved a total of 75 strains of yeast isolated from the blood of in-patients of the Public Hospital, Botucatu, Sao Paulo, Brazil, with a clinical profile of fungemia. The hospital wards with the largest number of fungemias were neonatal intensive care units (ICUs) (32%) followed by gastric surgery (13.4%) and pediatric wards (10.7%). After identification, the samples were analyzed for the production of phospholipase and proteinase enzymes, and biotyped according to their susceptibility to 'killer'toxins. Results. - The most frequent species found was Candida albicans (38.7%) followed by C. parapsilosis (30.7%). In terms of enzyme production, 98.7% of the 75 samples of yeast presented a strongly positive activity for proteinase; however, 78.7% did not present any phospholipasic activity. Six different biotypes were identified, the most frequent being 511 and 888. Conclusion. - In association with phenotypic methods, genetic analyses should also be made of the samples under study to help in the rational development of a wider range of preventive measures and better control of hospital-contracted infections. Resume Objectif. - Le but de cette etude a ete d'analyser sur le plan taxonomique 75 souches de levures isolees de fongemies et de determiner et de comparer les facteurs de virulence et les phenotypes de ces souches. Methodes. - Nous avons etudie 75 souches de levures isolees du sang de patients hospitalises a l'Hopital Public de Botucatu, Sao Paulo, Bresil. Le plus grand nombre de fongemies a ete observe dans l'unite de soins intensifs neonataux (32 %) suivi de la chirurgie gastrique (13,4 %) et pediatrique (10,7 %). Apres identification, les souches ont ete etudiees pour leur production de phospholipase et proteinase et biotypees selon leur sensibilite aux toxines 'killer'. Resultats. - L'espece plus frequente a ete Candida albicans (38,7 %) suivi par C. parapsilosis (30,7 %). En fonction de leur production d'enzymes, 97,3 % des 75 souches ont presente une activite positive tres forte pour la proteinase, mais 78,7 % n'ont pas presente une activite de phospholipase. Six biotypes ont ete obtenus ; les plus frequents ont ete les biotypes 511 et 888. Conclusion. - En association avec les methodes phenotypiques, les isolats de ces patients doivent etre aussi etudies genetiquement afin de trouver des mesures preventives et de meilleurs controles au niveau de l'hopital.