Risk factors and molecular epidemiology of carbapenem-Resistant Acinetobacter calcoaceticus-baumannii complex at a district hospital in Taiwan

Aims: The aims of this study were to identify the risk factors and describe molecular epidemiology carbapenem-resistant Acinetobacter calcoaceticus-baumannii complex (ACB complex) at a district hospital in Taiwan. Materials and Methods: This is a case–control study at a district hospital in the Penghu Islands, Taiwan, from May 2014 to June 2016. Patients with carbapenem-resistant ACB complex and controls with carbapenem-nonresistant ACB complex were identified, and relevant clinical data obtained from them were compared. Risk factors for carbapenem-resistant ACB complex isolation were searched using bivariable and multivariable analysis. The available isolates from patients were genotyped using a pulsed-field gel electrophoresis (PFGE) method. Results: A total of 70 patients were included in this study (36 cases and 34 controls). A bivariable analysis showed that patients who had a hospital admission within the past 3 months and had a recent nasogastric tube insertion had a tendency for subsequent carbapenem-resistant ACB complex isolation ( P = 0.066 and 0.051, respectively). Previous exposure to fluoroquinolones was significantly associated with the occurrence of carbapenem-resistant ACB complex ( P = 0.028). Further multivariable analysis showed that previous exposure to fluoroquinolones (odds ratio, 10.477; 95% confidence interval, 1.117–98.270; P = 0.040) was an independent risk factor associated with the occurrence of carbapenem-resistant ACB complex. According to PFGE for available carbapenem-resistant ACB complex isolates, one major clone was disseminated in the hospital. Conclusions: The antibiotic selective pressure of fluoroquinolone and interpatient dissemination contributed to the occurrence of carbapenem-resistant ACB complex.