Mechanisms involved in resistance to carbapenems among Acinetobacter baumannii isolates recovered in Brazil: A systematic review and meta-analysis

Abstract

Introduction: Infections caused by carbapenem-resistant Acinetobacter baumannii(CRAB) is a health problem due to the limited therapeutic options available. This study was carried out to evaluate the main mechanisms of resistance of carbapenems in CRAB in the last 10 years in Brazil and to describe the susceptibility profile to tigecycline and polymyxins in these isolates. Material and methods: A systematic review was carried out according to Prisma in PUBMED/MEDLINE, Scopus, SciELO, Biblioteca Virtual de Saúde (BVS) and Cochrane Library. Data regarding enzyme resistance to carbapenems were evaluated by meta-analysis according to the random effect. Results: 21 articles were selected according to inclusion and exclu-sion criteria that evaluated 1096 CRAB. Most of the studies were carried out in the southern (33.3 %) and southeast (23.8 %) regions of Brazil (33.3 %) and in 2016 and 2018. According to the meta-analyzes, OXA-type carbapenemase was the main mechanism involved in the low susceptibility to carbapenems in CRAB (98%; 95% CI: 0.91, 0.99; I² = 95%), with blaOXA-23-like(91 %; 95 % CI: 0.76; 0.97; I² = 97 %) or blaOXA-51-like/ ISAba1 (84 %; 95 % CI: 0.15, 0.99; I² = 98 %) genes, followed by metallo-β-lactamases (MBL) (12 %, 95 % CI: 0.09, 0.15, I² = 99 %) and Klebsiella pneumoniae carbapenemase (KPC) (6 %, 95 % CI: 0.04; 0.08; I² = 87 %). Conclu-sion: The included studies showed that susceptibility to colistin (99 %) and tigecy-cline (93 %) remains high and was not affected by carbapenem resistance.