RESUMO
Abstract: INTRODUCTION: Members of the Acinetobacter genus are key pathogens that cause healthcare-associated infections, and they tend to spread and develop new antibiotic resistance mechanisms. Oxacillinases are primarily responsible for resistance to carbapenem antibiotics. Higher rates of carbapenem hydrolysis might be ascribed to insertion sequences, such as the ISAba1 sequence, near bla OXA genes. The present study examined the occurrence of the genetic elements bla OXA and ISAba1 and their relationship with susceptibility to carbapenems in clinical isolates of the Acinetobacter calcoaceticus-Acinetobacter baumannii complex. METHODS: Isolates identified over 6 consecutive years in a general hospital in Joinville, Southern Brazil, were evaluated. The investigation of 5 families of genes encoding oxacillinases and the ISAba1 sequence location relative to bla OXA genes was conducted using polymerase chain reaction. RESULTS: All isolates presented the bla OXA-51-like gene (n = 78), and 91% tested positive for the bla OXA-23-like gene (n = 71). The presence of ISAba1 was exclusively detected in isolates carrying the bla OXA-23-like gene. All isolates in which ISAba1 was found upstream of the bla OXA-23-like gene (n = 69) showed resistance to carbapenems, whereas the only isolate in which ISAba1 was not located near the bla OXA-23-like gene was susceptible to carbapenems. The ISAba1 sequence position of another bla OXA-23-like-positive isolate was inconclusive. The isolates exclusively carrying the bla OXA-51-like gene (n = 7) showed susceptibility to carbapenems. CONCLUSIONS: The presence of the ISAba1 sequence upstream of the bla OXA-23-like gene was strongly associated with carbapenem resistance in isolates of the A. calcoaceticus-A. baumannii complex in the hospital center studied.
Assuntos
Humanos , Proteínas de Bactérias/genética , DNA Bacteriano/genética , Carbapenêmicos/farmacologia , Acinetobacter calcoaceticus/efeitos dos fármacos , Resistência beta-Lactâmica/genética , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Fenótipo , Proteínas de Bactérias/metabolismo , Brasil , Infecções por Acinetobacter/microbiologia , Reação em Cadeia da Polimerase , Eletroforese em Gel de Campo Pulsado , Acinetobacter calcoaceticus/isolamento & purificação , Acinetobacter calcoaceticus/genética , Acinetobacter baumannii/isolamento & purificação , Acinetobacter baumannii/genética , GenótipoRESUMO
Abstract: INTRODUCTION: Carbapenems are the therapy of choice for treating severe infections caused by the Acinetobacter calcoaceticus-Acinetobacter baumannii complex. We aimed to assess the prevalence and antimicrobial susceptibility profiles of producers of distinct oxacillinases among nosocomial isolates of the A. calcoaceticus-A. baumannii complex in a 249-bed general hospital located in Joinville, Southern Brazil. METHODS: Of the 139 A. baumannii clinical isolates with reduced susceptibility to carbapenems between 2010 and 2013, 118 isolates from varying anatomical sites and hospital sectors were selected for genotypic analysis. Five families of genes encoding oxacillinases, namely blaOXA-23-like, blaOXA-24-like, blaOXA-51-like, blaOXA-58-like, and blaOXA-143-like, wereinvestigated by multiplex polymerase chain reaction (PCR). RESULTS: Most (87.3%) isolates simultaneously carried the blaOXA-23-likeand blaOXA-51-likegenes, whereas three (2.5%) isolates harbored only blaOXA-51-likeones. The circulation of carbapenem-resistant isolates increased during the study period: from none in 2010, to 22 in 2011, 64 in 2012, and 53 in 2013. CONCLUSIONS: Isolates carrying the blaOXA-23-likeand blaOXA-51-likegenes were widely distributed in the hospital investigated. Because of the worsening scenario, the implementation of preventive measures and effective barriers is needed.
Assuntos
Humanos , Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Infecção Hospitalar/microbiologia , beta-Lactamases/genética , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/genética , Brasil , Testes de Sensibilidade a Antimicrobianos por Disco-Difusão , Genótipo , Reação em Cadeia da Polimerase Multiplex , Fenótipo , beta-Lactamases/efeitos dos fármacosRESUMO
Investigar a associação entre fatores de risco genéticos, comportamentais, biológicos e médicos e a ocorrência da prematuridade. Realizou-se estudo retrospectivo do tipo caso-controle. A técnica de reação em cadeia da polimerase em tempo real foi utilizada para analisar a influência dos polimorfismos rs12473815 do gene codificante para o receptor do hormônio folículo estimulante ( Os genótipos CT do polimorfismo rs12473815 e TC e CC do polimorfismo rs1942836 mostraram-se associados a uma maior chance de desenvolver parto prematuro. Observou-se associação entre o nascimento prematuro e a ingestão alcoólica quando o consumo ocorreu em duas ou mais ocasiões mensais. O baixo índice de massa corporal pré-gestacional se mostrou preditor do nascimento prematuro espontâneo, enquanto o elevado índice de massa corporal reduziu a sua probabilidade. Os resultados encontrados sugerem que a ingestão alcoólica excessiva, o baixo índice de massa corporal pré-gestacional e os alelos de risco dos polimorfismos rs12473815 e rs1942836 dos genes
To investigate the association between genetic, behavioral, biological and medical risk factors and the occurrence of preterm birth. A retrospective case-control study was conducted. The real-time polymerase chain reaction was used to analyze the influence of the rs12473815 polymorphism of the follicle stimulating hormone receptor gene ( The genotypes CT of rs12473815 and CT and CC of rs1942836 were associated with a higher chance of premature delivery. There was an association between preterm birth and alcohol intake when consumption occurred 2 or more times per month. Low pre-pregnancy body mass index was a predictor of spontaneous preterm birth, while high body mass index reduced this likelihood. The results suggest that excessive alcohol intake, a low level of pre-pregnancy body mass and the risk alleles of rs12473815 and rs1942836 polymorphisms of the FSHR and PGR genes, respectively, influence the occurrence of preterm birth.