Phenotypic and genotypic characterization of multidrug-resistant Acinetobacter baumannii isolated in Algerian hospitals

  • Nabila Benamrouche Medical Bacteriology Laboratory, Institut Pasteur of Algeria, Algiers, Algeria
  • Ourida Lafer Medical Bacteriology Laboratory, Institut Pasteur of Algeria, Algiers, Algeria
  • Lahcen Benmahdi University Regional Military Hospital of Oran, Oran, Algeria
  • Akila Benslimani Central Laboratory, Specialized Hospital Establishment Maouche Mohand Amokrane, Algiers, Algeria
  • Wahiba Amhis Central Laboratory, Public Hospital Establishment Ibn Ziri of Bologhine, Algiers, Algeria
  • Houria Ammari Central Laboratory, University Hospital of Beni Messous, Algiers, Algeria
  • Farida Assaous Medical Bacteriology Laboratory, Institut Pasteur of Algeria, Algiers, Algeria
  • Amina Azzam Microbiology and Parasitology Laboratory, University Hospital of Tizi Ouzou, Tizi Ouzou, Algeria
  • Kheira Rahal Medical Bacteriology Laboratory, Institut Pasteur of Algeria, Algiers, Algeria
  • Hassiba Tali Maamar Medical Bacteriology Laboratory, Institut Pasteur of Algeria, Algiers, Algeria
Keywords: Multidrug-resistant Acinetobacter baumannii, blaCTX-M-15, blaSHV-33, blaNDM-1, colistin-resistance, Algeria

Abstract

Introduction: The aim of this study was to investigate the drug-resistance and the molecular characterization of carbapenemases, ESBL, and aminoglycoside-modifying enzymes among Acinetobacter baumannii clinical isolates in Algerian hospitals.

Methodology: A total of 92 A. baumannii isolates were collected between 2012 and 2016. Antimicrobial susceptibility testings were performed for β-lactams, aminoglycosides, fluoroquinolones, trimethoprim-sulfamethoxazole, rifampicin and colistin. The phenotypic characterization of β-lactamases was investigated. For 30 randomly targeted strains, the carriage of the carbapenemases, ESBL and aminoglycoside-modifying enzymes -encoding genes was determined by PCR. Sequencing was carried out for carbapenemases and ESBL genes.

Results: Most of the 92 isolates studied were recovered from hospitalized patients (93.5%) and were mainly from intensive care units (51.1%) and orthopedics (19.6%). The strains were collected primarily from low respiratory tract (33.7%), wounds (23.9%) and urine (16.3%). Multidrug-resistant A. baumannii strains were prevalent (96.7%). High rates of resistance were observed for almost all antibiotics tested (>70%) excluding rifampicin (7.6%) and colistin (5.4%). For the five colistin-resistant strains, MICs ranged between 4 and 128 µg/mL. Positive MBL (83.7%) and ESBL (23.9%) strains were identified. Regarding β-lactams, the blaNDM and both blaSHV and blaCTX-M1 genes were detected in five and two strains respectively. Sequencing of the genes revealed the presence of blaNDM-1, blaCTX-M-15, and blaSHV-33. For aminoglycosides, aac(6’)-Ib, ant(2’’)-I and aph(3’)-VI genes were detected in three, seven and six strains respectively.

Conclusions: Here, we report the first co-occurrence of extended-spectrum β-lactamases SHV-33 and CTX-M-15, the carbapenemase NDM-1 and the emergence of colistin-resistant A. baumannii in Algerian hospitals.

Published
2020-12-31
How to Cite
1.
Benamrouche N, Lafer O, Benmahdi L, Benslimani A, Amhis W, Ammari H, Assaous F, Azzam A, Rahal K, Tali Maamar H (2020) Phenotypic and genotypic characterization of multidrug-resistant Acinetobacter baumannii isolated in Algerian hospitals. J Infect Dev Ctries 14:1395-1401. doi: 10.3855/jidc.12348
Section
Original Articles