Candidemia by Candida parapsilosis in a neonatal intensive care unit: human and environmental reservoirs, virulence factors, and antifungal susceptibility.

The Candida parapsilosis complex has emerged as one of the main causes of candidemia worldwide. This study aims to evaluate possible C. parapsilosis sensu stricto reservoirs in a NICU, the expression of virulence factors, and antifungal susceptibility, and to analyze their genetic and phenotypic similarity. The study included 17 isolates of C. parapsilosis: seven environmental, one from a newborn's mother, and nine samples from six newborns. We used molecular and phenotypic tests to characterize the isolates and to trace possible routes of infection. The genetic similarity was determined by random amplified polymorphic DNA. The hemolytic and DNAse activity was determined using sheep's blood and DNAse agar, biofilm production by XTT method, and the susceptibility to antifungals through microdilution methodology. Two environmental strains isolated in the same month had high similarity. The 17 isolates expressed at least one of the three virulence factors studied, and one environmental isolate was resistant to fluconazole. This study shows that environmental contamination can be an important reservoir of potentially pathogenic microorganisms, since isolates of C. parapsilosis sensu stricto collected from the hospital environment were able to express virulence factors. Therefore, we emphasized the importance of determining the transmission routes in NICU in order to detect pathogen sources and reservoirs, as well as to establish prevention measures, such as adequate disinfection of the environment.

High-resolution fingerprinting of Candida parapsilosis isolates suggests persistence and transmission of infections among neonatal intensive care unit patients in Kuwait.

Candida parapsilosis causes ~35% of all candidemia cases in neonates. High-resolution fingerprinting of C. parapsilosis isolates from neonatal intensive care unit (NICU) patients in Maternity Hospital (MH) was performed to identify epidemiologically related strains. Sixty-eight bloodstream/colonizing strains isolated from 59 NICU patients, two isolates from health care workers (HCWs) from MH and 18 bloodstream isolates from two other hospitals were used. Six microsatellite markers were employed, isolates were assigned a numerical microsatellite genotype (MSG), dendrogram was constructed and similarities between genotypes were visualized by minimum spanning tree. Fifty bloodstream isolates from MH yielded 37 MSGs with 20 isolates clustering in 7 MSGs. Duplicate isolates and colonizing strains yielded same/highly similar MSG as bloodstream isolates. Colonizing strains from two non-candidemia patients yielded unique MSGs while others belonged to a cluster. All isolates from HCWs and from two other hospitals belonged to unique MSGs. Cluster isolates came from patients in NICU-1 or from neonates in NICU-1 and other NICUs. Clonal complexes comprising closely related genotypes indicative of microevolution were also detected. Our data show that some C. parapsilosis strains have persisted in MH environment over several years and these endemic genotypes were transmitted to other patients in NICU-1 and/or other nearby NICUs.

Detection of neonatal unit clusters of Candida parapsilosis fungaemia by microsatellite genotyping: Results from laboratory-based sentinel surveillance, South Africa, 2009-2010.

Neonatal candidaemia is a common, deadly and costly hospital-associated disease. To determine the genetic diversity of Candida parapsilosis causing fungaemia in South African neonatal intensive care units (NICUs). From February 2009 through to August 2010, cases of candidaemia were reported through laboratory-based surveillance. C. parapsilosis isolates from neonatal cases were submitted for identification by internal transcribed spacer (ITS) region sequencing, antifungal susceptibility testing and microsatellite genotyping. Cluster analysis was performed using Unweighted Pair Group Method with Arithmetic Mean (UPGMA). Of 1671 cases with a viable Candida isolate, 393 (24%) occurred among neonates. Isolates from 143 neonatal cases were confirmed as C. parapsilosis sensu stricto. Many isolates were resistant to fluconazole (77/143; 54%) and voriconazole (20/143; 14%). Of 79 closely-related genotypes, 18 were represented by ≥2 isolates; 61 genotypes had a single isolate each. Seven clusters, comprised of 82 isolates, were identified at five hospitals in three provinces. Isolates belonging to certain clusters were significantly more likely to be fluconazole resistant: all cluster 7 isolates and the majority of cluster 4 (78%), 5 (89%) and 6 (67%) isolates (P<.001). Candida parapsilosis-associated candidaemia in public-sector NICUs was caused by closely related genotypes and there was molecular evidence of undetected outbreaks as well as intra-hospital transmission.

Use of organs from donors with bloodstream infection, pneumonia, and influenza: Results of a survey of infectious diseases practitioners.

BACKGROUND: Potential organ donors may be admitted with an infection to an intensive care unit, or contract a nosocomial infection during their stay, increasing the risk of potential transmission to the recipient. Because of a lack of practice guidelines and large-scale data on this topic, we undertook a survey to assess the willingness of transplant infectious diseases (ID) physicians to accept such organs. METHODS: We performed a 10-question survey of ID providers from the American Society of Transplantation Infectious Disease Community of Practice to determine the scope of practice regarding acceptance of organs from donors with bloodstream infection, pneumonia, and influenza prior to organ procurement, as well as management of such infections following transplantation. RESULTS: Among 60 respondents to our survey, a majority indicated that organs would be accepted from donors bacteremic with streptococci (76%) or Enterobacteriaceae (73%) without evidence of drug resistance. Acceptance rates varied based on infecting organism, type of organ, and center size. Ten percent of respondents would accept an organ from a donor bacteremic with a carbapenem-resistant organism. Over 90% of respondents would accept an organ other than a lung from a donor with influenza on treatment, compared with 52% that would accept a lung in the same setting. CONCLUSIONS: This study is the first to our knowledge to survey transplant ID providers regarding acceptance of organs based on specific infections in the donor. These decisions are often based on limited published data and experience. Better characterization of the outcomes from donors with specific types of infection could lead to liberalization of organ acceptance practices across centers.

Genetic diversity among Candida albicans isolates associated with vertical transmission in preterm triplets.

We report a case of congenital candidiasis in triplets, in the context of premature labor at 25 weeks gestation, without symptomatic vaginitis or chorioamnionitis. All three infants died as a result of prematurity, aggravated by systemic candidiasis. Multi-locus sequence typing confirmed vertical transmission of Candida albicans from the mother to the triplets and revealed a slight diversity among the strains isolated from the neonates.

Management of fungal infections in the intensive care unit: a survey of UK practice.

BACKGROUND: Candida species are a common cause of nosocomial bloodstream infection. Such infections commonly affect patients in the intensive care unit (ICU) and carry a high mortality. There are published guidelines for the management of fungal infections, but there are no data on the usual management of invasive Candida infections in UK ICUs. METHODS: An electronic survey was sent by email to a representative clinician in 236 ICUs, over 90% of units in the UK. Questions related to the institution of empirical therapy and to the management of proven candidaemia. RESULTS: There were 72 responses. A minority of units follow a policy regarding the management of these infections but the involvement of microbiologists is usual. Empirical therapy is used in 85.9% of units, often for patients perceived to be at high risk. Fluconazole is the most commonly used antifungal agent, both for empirical therapy and for the treatment of proven candidaemia. For candidaemic patients, 73.9% of ICUs frequently or always remove central venous catheters within 48 h, while 15.1% frequently or always arrange ophthalmology review. CONCLUSIONS: Management of fungal infections is relatively consistent among responding units. However, recent developments in the field have not yet been incorporated into standard practice. Adherence to published guidelines could be improved, potentially reducing morbidity and mortality from these common infections.