Molecular Epidemiology and Clinical Characteristics of Metallo-beta-lactamase Producing Pseudomonas aeruginosa Isolates

Abstract

Introduction:In this study, we aimed to determine the epidemiological properties of metallo-beta-lactamase-producing Pseudomonas aeruginosa (MBL-PA) isolates and to investigate the relationship between the presence of MBL-PA and patient morbidity and mortality. Materials and Methods: The study included carbapenem-resistant P. aeruginosa isolates recovered from various clinical specimens of 334 patients in Karadeniz Technical University Faculty of Medicine Hospital, a 900-bed university hospital in Trabzon, Turkey. MBL-related carbapenem-resistant PA strains were phenotypically investigated using the Modified Hodge test and the imipenem/imipenem-ethylene diamine tetra acetic acid combined disc tests. Multiplex polymerase chain reaction was used to investigate the presence of bla IMP , bla VIM , bla GIM , bla SIM , and bla SPM genes, which are responsible for MBL production. Clonal relationships among MBL-PA isolates were analyzed by pulsed-field gel electrophoresis. The patients' hospital records were retrospectively examined. Various demographic and clinical characteristics were evaluated in relation to MBL-PA. Results: Thirty-two (9.6%) of the carbapenem-resistant PA isolates were found to carry bla VIM and/or bla IMP , with three strains harboring both bla VIM and bla IMP . MBL-PA isolates were more resistant to aminoglycosides and quinolones. Eight Verona integron-encoded metallo-beta-lactamase-type MBL-PA isolates were found to be identical in adults, while several clonally-related clusters were observed among MBL-PA isolates in both the pediatric and adult inpatients. Compared to non-MBL carbapenem-resistant PA, the risk factors evaluated were found to have no association with MBL-PA. In addition, there was no statistically significant difference in mortality between patients from whom MBL-PA or non-MBL-PA was isolated. Conclusion: Although MBL-PA has been implicated in various healthcare-related outbreaks, no specific risk factor has been identified in association with MBL-PA isolation. To our knowledge, this is the first study in Turkey to detect P. aeruginosa isolates carrying both bla VIM and bla IMP .Giriş: Bu çalışmada metallo-beta-laktamaz üreten Pseudomonas aeruginosa (MBL-PA) suşlarının moleküler epidemiyolojik özelliklerinin belirlenmesi ve MBL-PA varlığının hasta mortalitesi ve morbiditesi ile ilişkisinin değerlendirilmesi amaçlandı. Gereç ve Yöntem: Karadeniz Teknik Üniversitesi Tıp Fakültesi Hastanesi'nde 2009-2010 yıllarında bir, çeşitli klinik örneklerden izole edilmiş 334 karbapenem dirençli P. aeruginosa kökeni çalışmaya dahil edildi. Karbapenem dirençli PA izolatlarında MBL varlığı fenotipik olarak Modified Hodge ve imipenem/imipenem-etilen diamin tetra asetik asit kombine disk testleri ile araştırıldı. MBL üretiminden sorumlu genlerden olan bla IMP , bla VIM , bla GIM , bla SIM ve bla SPM genlerinin varlığı çoklu polimeraz zincir reaksiyonu yöntemi ile araştırıldı. MBL-PA olduğu belirlenen suşların klonal ilişkisi pulsedfield jel elektroforez ile analiz edildi. Hastaların tıbbi kayıtları g...

Bacterial Infection of Burn Patients and Their Drug-resistance in South Jiangsu China During 2012-2016

“…Cephalosporin antibiotics were the conventional treatment in the clinic, but we found the top 3 predominant bacteria had very high resistance rates to most cephalosporin antibiotics (above 50%), except for Cefoperazone/Sulbactam (44.5%). According to other research [12], β-lactam antibiotics have been improved, with some new drugs FDA approved in recent years that were very effective, such as Ceftazidime-Avibactam, Ceftolozane/Tazobactam, Dalbavancin, etc. However, because bacteria evolve very rapidly, these new upgraded drugs may be ineffective on the mutant bacteria.…”