High colonization by Candida parapsilosis sensu stricto on hands and surfaces in an adult intensive care unit

J Mycol Med. 2021 Jun;31(2):101110. doi: 10.1016/j.mycmed.2020.101110. Epub 2021 Jan 4.

Abstract

Background: Yeasts of the Candida parapsilosis complex have frequently been reported as agents of fungal infection in Brazil and worldwide, most of the cases are related to hospital-acquired infection. C. parapsilosis is the third most common cause of candidemia, and the hands of hospital workers as well as hospital surfaces have been suggested as possible sources.

Objectives: In this study we verified the frequency of C. parapsilosis on the hands of workers and on surfaces in the adult intensive care unit (AICU) of a tertiary hospital in Paraná-Brazil.

Methods: Surface samples were collected with swabs moistened with saline, and a plastic bag with distilled water was used to collect samples from hands. The yeasts were identified by morphology, MALDI-TOF mass spectrometry and PCR-RFLP of the secondary alcohol dehydrogenase-encoding gene (SADH) after digestion with the restriction enzyme BanI.

Results and conclusions: A total of 223 yeast were found, of which 101 (45.29%) were identified as C. parapsilosis sensu stricto. Of these, 46.66% (n=35) were found on surfaces and 44.59% (n=66) on the hands of the employees. The analysis of C. parapsilosis strains by microsatellite loci (CP1, CP4, CP6 and B5) showed 80 different genotypes. Their antifungal susceptibility profile, evaluated by the microdilution broth method, revealed that C. parapsilosis was sensitive to amphotericin B, fluconazole and voriconazole, but not to micafungin. The results revealed the heterogeneity of the yeast population, suggesting that there is no common source of contamination in the AICU of this hospital.

Keywords: Candida parapsilosis; Hands; Hospital surfaces; Infection; Intensive care unit; Polymerase Chain Reaction.

MeSH terms

  • Adult
  • Antifungal Agents / pharmacology
  • Candida parapsilosis / classification
  • Candida parapsilosis / drug effects
  • Candida parapsilosis / genetics*
  • Candida parapsilosis / isolation & purification*
  • Cross Infection / microbiology*
  • Drug Resistance, Fungal
  • Genetic Variation
  • Hand / microbiology*
  • Health Personnel / statistics & numerical data*
  • Humans
  • Intensive Care Units / statistics & numerical data*
  • Mass Spectrometry
  • Mycological Typing Techniques
  • Polymorphism, Restriction Fragment Length
  • Tertiary Care Centers

Substances

  • Antifungal Agents