Effect of carbapenems exposure on multiple drug resistance and prognosis of Acinetobacter baumannii infection

Abstract

Objective To investigate the effect of carbapenems exposure on multiple drug resistance and prognosis of Acinetobacter baumannii (AB) infection. Methods The clinical data of 120 patients with confirmed as nosocomial infection from April 2016 to April 2018 in Huizhou First People’s Hospital were analyzed, retrospectively. According to the exposure of carbapenems or not, the 120 patients were divided into two groups: carbapenems exposure group (59 cases) and non-carbapenems exposure group (61 cases). The detection rates of AB infection and multidrug-resistant Acinetobacter baumannii (MDRAB) of the two groups were compared. The rate of detection and drug resistance of carbapenems resistant Acinetobacter baumannii (CRAB) were analyzed, respectively. Logistic regression model was used to analyze the risk factors influencing the prognosis of patients with AB infection. Results Carbapenems exposure group had higher rate of AB infection and detection rate of MDRAB than those of non-carbapenems exposure group, with significant differences (79.66% vs 19.67%, χ2AB = 43.184, P < 0.001; 71.19% vs 3.28%, χ2MDRAB = 59.558, P < 0.001). A total of 92 strains of CRAB were detected, and the detection rate of CRAB in 2017-2018 increased by 87.50% compared with that of 2016-2017. All 92 strains of CRAB were resistant to cephalosporins, carbapenems, piperaxelin, piperaxillin/tazobartan, gentamycin and fosfomycin with different degrees, but only sensitive to amikacin and ciprofloxacin. The mortality rate of patients in carbapenems exposure group was higher than that of non-carbapenems exposure group (42.37% vs 9.84%, χ2 = 16.572, P < 0.001). Single factor analysis showed that poor prognosis of patients with AB infection was related to hospitalization stay in ICU (χ2 = 8.563, P = 0.003), mechanical ventilation (χ2 = 10.898, P = 0.001), indwelling urinary catheter (χ2 = 12.725, P < 0.001), indwelling central venous catheter (χ2 = 6.306, P = 0.012), using cephalosporin (χ2 = 25.095, P < 0.001), carbapenems exposure (χ2 = 33.005, P < 0.001) and combined antibiotic application (χ2 = 8.241, P = 0.004), all with significant differences. Logistic analysis showed that carbapenems were independently associated with the prognosis of patients with AB infection (OR = 10.687, 95%CI: 0.025-0.937; P < 0.001). Conclusions Carbapenems could increase the rate of AB infection and lead to multiple drug resistance, which is an independent risk factor for poor prognosis to patients with AB infection. Key words: Carbapenems; Acinetobacter baumannii; Multidrug resistance; Prognosis