Feevale, Laboratory of Biomedicine, Novo Hamburgo, RS.
Braz J Infect Dis. 2009 Jun;13(3):170-2. doi: 10.1590/s1413-86702009000300003.
This study determined the prevalence of metallo-beta-lactamase (MBL)-producing Pseudomonas aeruginosa in two hospitals located in the Southern part of Brazil and compare the performance of two different phenotypic tests. Thirty-one non-repetitive Pseudomonas aeruginosa isolates from various clinical samples from patients admitted to two hospitals located in Rio Grande do Sul, Brazil (twenty-three from a hospital in Porto Alegre City and eight isolates from a hospital in Vale dos Sinos Region). All strains suggestive of possessing MBLs by phenotypic methods were included in this study. Phenotypic detection of MBLs was carried out simultaneously by using both the MBL Etest and disk approximation test using 2-mercaptopropionic acid close to a ceftazidime disk. Strains positive were further confirmed using molecular techniques for bla(VIM), bla(IMP) and bla(SPM-1). The prevalence of MBLs from samples of inpatients from the hospital located in Porto Alegre was 30.4% and that of inpatients from Vale dos Sinos hospital was only 3.1%. Only MBL type SPM-1 was detected in these samples by molecular analysis and all were detected by the Etest MBL strips. The prevalence of P. aeruginosa that produce MBLs can be markedly different in distinct geographical areas, even among different hospitals in the same area. In our study, the EDTA-based method was the only method able to detect all strains harboring the SPM-1 enzyme.
本研究旨在确定巴西南部两家医院中产金属β-内酰胺酶（MBL）的铜绿假单胞菌的流行率，并比较两种不同表型检测方法的性能。从巴西南里奥格兰德州的两家医院（阿雷格里港市的一家医院和瓦尔代斯桑托斯地区的一家医院）的住院患者的各种临床标本中分离出 31 株非重复的铜绿假单胞菌。所有通过表型方法提示具有 MBL 的菌株均包含在本研究中。使用 MBL Etest 和 2-巯基丙酸接近头孢他啶纸片的纸片近似试验同时进行表型检测 MBLs。阳性菌株进一步使用 bla(VIM)、bla(IMP)和 bla(SPM-1)的分子技术进行确认。来自阿雷格里港市医院住院患者样本中的 MBLs 流行率为 30.4%，而来自瓦尔代斯桑托斯医院的住院患者样本中的流行率仅为 3.1%。通过分子分析仅在这些样本中检测到 MBL 型 SPM-1，并且所有这些样本均通过 Etest MBL 条带检测到。在不同地区，甚至在同一地区的不同医院之间，产 MBL 的铜绿假单胞菌的流行率可能存在显著差异。在我们的研究中，基于 EDTA 的方法是唯一能够检测所有携带 SPM-1 酶的菌株的方法。
