Outbreak of fungemia caused by Candida parapsilosis in a neonatal intensive care unit: molecular investigation through microsatellite analysis.

BACKGROUND: Opportunistic infections are an increasingly common problem in hospitals, and the yeast Candida parapsilosis has emerged as an important nosocomial pathogen, especially in neonatal intensive care units (NICUs) where it has been responsible for outbreak cases. Risk factors for C. parapsilosis infection in neonates include prematurity, very low birth weight, prolonged hospitalization, indwelling central venous catheters, hyperalimentation, intravenous fatty emulsions and broad spectrum antibiotic therapy. Molecular methods are widely used to elucidate these hospital outbreaks, establishing genetic variations among strains of yeast. AIMS: The aim of this study was to detect an outbreak of C. parapsilosis in an NICU at the "Hospital das Clinicas", Faculty of Medicine of Botucatu, a tertiary hospital located in São Paulo, Brazil, using the molecular genotyping by the microsatellite markers analysis. METHODS: A total of 11 cases of fungemia caused by C. parapsilosis were identified during a period of 43 days in the NICU. To confirm the outbreak all strains were molecularly typed using the technique of microsatellites. RESULTS: Out of the 11 yeast samples studied, nine showed the same genotypic profile using the technique of microsatellites. CONCLUSIONS: Our study shows that the technique of microsatellites can be useful for these purposes. In conclusion, we detected the presence of an outbreak of C. parapsilosis in the NICU of the hospital analyzed, emphasizing the importance of using molecular tools, for the early detection of hospital outbreaks, and for the introduction of effective preventive measures, especially in NICUs.

Candida isolated from vaginal mucosa of mothers and oral mucosa of neonates: occurrence and biotypes concordance.

BACKGROUND: The common occurrence of Candida spp. on the vaginal mucosa of pregnant women suggests this as the source of neonatal candidiasis. METHODS: This study investigated the occurrence of yeasts on the vaginal mucosa of 100 mothers at the time of birth, and on the oral mucosa of their respective neonates, all full-term, on the 1st, 3rd, and 9th days after birth by vaginal (72 cases) and cesarean (28 cases) routes. In each case where concordance at the level of species was found between the isolate from the mother and that from the neonate, tests were made to check for concordance between the genotypic and phenotypic profiles (susceptibility to killer toxins, serotyping, proteinase and phospholipase production, and susceptibility to antifungal agents). RESULTS: For the vaginal-route group, yeasts were recovered from the vaginal mucosa of 47.2% of the mothers and from 25% of the neonates. For the cesarean-route group, these rates were 46.4% and 3.6%, respectively. Species found most frequently in the samples from the mothers and the neonates were, respectively C. albicans and C. guilliermondii. For the vaginal-route group, the rate of mother/neonate concordance at the level of species was 23.5% and no cases of concordance for the cesarean births. Of these cases with species concordance, there was concordance between the genotypic and phenotypic profiles in 6% (2 cases). CONCLUSION: The vaginal mucosa was not the main route of transmission of the Candida species to the neonate, because there was concordance between the genotypic and phenotypic profiles in only 6% (2 cases).