Molecular typing, virulence traits and risk factors of pandrug-resistant Acinetobacter baumannii spread in intensive care unit centers of Baghdad city, Iraq

Abstract

Objective: The virulence traits of pandrug-resistant (PDR) Acinetobacter baumannii strains have not been fully disclosed. Our aim was the assessment of PDR-A. baumannii (PDR-AB) virulence traits and risk factors in the intensive care unit (ICU), Baghdad, Iraq. Methods: Among 689 samples, 200 of them were identified as A. baumannii. In the disk diffusion test, 150 of them were PDR-AB. The virulence factors and antibiotic resistance genes were screened using the polymerase chain reaction (PCR) technique. Pulsed-field gel electrophoresis (PFGE) was performed for genetic typing of strains. Results: The age range >55 years (141/150, P < 0.0001), previous hospitalization (133/150, P < 0.001) and consumption of antibiotics (149/150, P < 0.0001), diabetes (122/150, P < 0.001) and prior contact to domestic animals (111/150, P = 0.00109) were significant risk factors associated with isolation of PDR-AB. PDR-AB from wound infections harbored the fimH, afa/draBC, csgA,cnf2, ibeA, cvaC, iutA, papC, traT, PAI, kpsMII, PapGII and papGIII. PFGE results outlined no clonal spread. Major drug resistance genes included blaOXA-23-like (100%), blaOXA-24-like (98%), tetA (98%), tetB (96%), dfrA (91%), sul1(75%), blaOXA-58-like (76%), blaOXA-51-like (76%) and aadA1 (76%). The fyuA gene was significantly (P = 0.039) higher in non-PDR-AB. Conclusion: A. baumannii with a high rate of virulence factors were detected among wound infections in ICU. In addition, the strains exhibited no genetic relation in the PFGE method. Risk factors of the high incidence of PDR-AB in Baghdad prior hospitalization and consumption of antibiotics, diabetes and contact with domestic animals. Therefore, there is a demand for control of PDR and virulent strains spread in healthcare settings.