RESUMO
PURPOSE: Cryptococcosis is acquired from the environment by the inhalation of Cryptococcus cells and may establish from an asymptomatic latent infection into pneumonia or meningoencephalitis. The genetic diversity of a Cryptococcus neoformans species complex has been investigated by several molecular tools, such as multi-locus sequence typing, amplified fragment length polymorphism (AFLP), restriction fragment length polymorphism and microsatellite analysis. This study aimed to investigate the genotype distributions and antifungal susceptibility profiles of C. neoformans sensu lato isolates from southern Brazil. METHODOLOGY: We studied 219 C. neoformans sensu lato isolates with mating- and serotyping, AFLP fingerprinting, microsatellite typing and antifungal susceptibility testing.Results/Key findings. Among the isolates, 136 (69â%) were from HIV-positive patients. Only C. neoformans mating-type α and serotype A were observed. AFLP fingerprinting analysis divided the isolates into AFLP1/VNI (n=172; 78.5â%), AFLP1A/VNII (n=19; 8.7â%), AFLP1B/VNII (n=4; 1.8â%) and a new AFLP pattern AFLP1C (n=23; 10.5â%). All isolates were susceptible to tested antifungals and no correlation between antifungal susceptibility and genotypes was observed. Through microsatellite analysis, most isolates clustered in a major microsatellite complex and Simpson's diversity index of this population was D=0.9856. CONCLUSION: The majority of C. neoformans sensu stricto infections occurred in HIV-positive patients. C. neoformans AFLP1/VNI was the most frequent genotype and all antifungal drugs had high in vitro activity against this species. Microsatellite analyses showed a high genetic diversity within the regional C. neoformans sensu stricto population, and correlation between environmental and clinical isolates, as well as a temporal and geographic relationship.
Assuntos
Antifúngicos/farmacologia , Criptococose/microbiologia , Cryptococcus neoformans/efeitos dos fármacos , Cryptococcus neoformans/isolamento & purificação , Farmacorresistência Fúngica , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Brasil , Cryptococcus neoformans/classificação , Cryptococcus neoformans/genética , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , Polimorfismo de Fragmento de RestriçãoRESUMO
BACKGROUND: Candida species are the primary cause of invasive fungal infection in hospitalized children. There are few data on risk factors for postoperative candidemia in pediatric patients with congenital heart defects. This study aimed to identify risk factors for candidemia in patients with congenital heart defects who underwent cardiac surgery. METHODS: This was a case-control study conducted in patients admitted to a pediatric cardiology intensive care unit from January 2006 to December 2013. Candidemia cases were matched with control patients without candidemia. Multivariate analyses were conducted to determine predictive probabilities for the incidence of candidemia at a risk higher than 10%. RESULTS: Thirty patients diagnosed with candidemia (incidence: 0.7 cases/1000 patient days) were matched with 75 controls. Risk factors independently associated with candidemia included Risk Adjustment for Congenital Heart Surgery (RACHS-1) category ≥3 [odds ratio (OR) = 3.165, 95% confidence interval: 1.377-8.467], use of acid suppression therapy (OR = 1.9, 95% confidence interval: 0.949-3.979) and thrombocytopenia (OR = 2.2, 95% confidence interval: 1.2-4.2). Predictive probabilities ranged from 11% (only in RACHS-1 category ≥3) to 58% (combined RACHS-1 ≥3, thrombocytopenia and acid suppression therapy use). The case fatality rate within 30 days after candidemia was 50%. CONCLUSION: This is the first report using the RACHS-1 category as a risk factor for invasive candidiasis in patients with congenital heart defects in the pediatric intensive care unit. Further studies must be conducted to validate the risk factors for candidemia in this pediatric population.