Investigation of the clonal associations in Acinetobacter Baumannii strains isolated from the respiratory samples of patients in a tertiary research hospital

Niger J Clin Pract. 2020 Aug;23(8):1155-1162. doi: 10.4103/njcp.njcp_549_18.

Abstract

Objective: The blaOXA resistance genes and ISAba1 were examined in 70 samples from lower respiratory tract of hospitalized patients.

Materials and methods: Of the 67 isolates obtained, almost half (46.3%) of them were from endotracheal aspirate, and most were collected from the intensive care units of the reanimation (37.3%) and internal medicine (32.8%) units.

Results: Three samples from the internal medicine intensive care unit had positive cultures. Of the multidrug resistant (MDR) samples, 70 isolates (>50%) were moderately sensitive, while fewer (10%) were resistant to tigecycline. In contrast, 100% were sensitive to colistin. All strains were found to be positive for blaOXA-23-like and blaOXA-51-like genes, whereas no blaOXA-40-like and blaOXA-58-like genes were detected. The ISAba1 positivity rate was 90.0%. Pattern 5 was mainly identified among the 22 different patterns. Of note, 50% of Pattern 5 was found in the patients of the internal medicine intensive care unit, and a third was associated with ventilator-associated pneumonia. Importantly, the internal medicine unit's equipment was found to be culture positive.

Conclusion: Findings obtained from this study suggest that isolates can easily spread through the hospital via isolate cross-contamination caused by health personnel. These contaminating isolates may be able to maintain their presence within the hospital for a long time.

Keywords: Acinetobacter baumannii; Diversi-Lab; clonal relation; rep-PCR.

MeSH terms

  • Acinetobacter Infections / drug therapy*
  • Acinetobacter Infections / microbiology
  • Acinetobacter baumannii / drug effects
  • Acinetobacter baumannii / genetics*
  • Acinetobacter baumannii / isolation & purification*
  • Adult
  • Aged
  • Aged, 80 and over
  • Anti-Bacterial Agents / pharmacology*
  • Bacterial Proteins / genetics
  • Colistin / pharmacology
  • DNA, Bacterial / genetics
  • Drug Resistance, Multiple, Bacterial / drug effects
  • Drug Resistance, Multiple, Bacterial / genetics*
  • Female
  • Genes, Bacterial
  • Humans
  • Intensive Care Units
  • Male
  • Microbial Sensitivity Tests
  • Middle Aged
  • Molecular Typing
  • Multiplex Polymerase Chain Reaction
  • Tertiary Care Centers
  • beta-Lactamases / genetics*

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • DNA, Bacterial
  • beta-Lactamases
  • beta-lactamase OXA-23, Acinetobacter baumannii
  • Colistin