Prevalence of Carbapenemase Encoding Genes and Antimicrobial Resistance Pattern of Enterobacteriaceae Isolated from Hospitalized Patients in Khartoum State, Sudan

Abstract

Carbapenem-resistant Enterobacteriaceae strains have been responsible for an increasing number of hospital-acquired infections globally. This study aimed to determine the prevalence of carbapenemase-producing Enterobacteriaceae and their frequency of antimicrobial-resistant patterns among hospitalized patients across three Khartoum State Teaching Hospitals, Sudan. Materials and Methods. A cross-sectional study was conducted at Khartoum State Teaching Hospitals from April 2018 to October 2019. A total of 384 non-duplicative Enterobacteriaceae strains were isolated from1062 clinical samples obtained from hospitalized patients receiving treatment across three main teaching hospitals. The samples were cultured into a MacConkey agar plate. The Enterobacteriaceae strains were differentiated by specific colony color and again by biochemical test. Antimicrobial susceptibility testing was performed by the disc diffusion method. The minimum inhibitory concentration (MIC) of imipenem and meropenem was performed by the agar dilution method. Multiplex polymerase chain reaction (PCR) was performed to investigate the presence of carbapenemase-encoding genes. Data analysis was carried out using SPSS version 21. Results. Of the 36.2% (384/10.62) nonduplicate of Enterobacteriaceae strains isolated from clinical samples, 122 (31.8%) were carbapenemase-producing Enterobacteriaceae (CPE). Of these isolates, 37 (30.3%) harbored the blaIMP followed by; 29 (23.8%) blaNDM, 21 (17.2%) blaOXA-48, 6 (4.9%) blaGES, 5 (4.1%) were blaKPC, 3(2.5%) blaGIM-1, 2(1.6%) blaVIM and 1 (0.8%) blaSIM-1, while the remaining 19(15.6%) isolates carried combinations carbapenemase blagenes. The most predominant CPE strains were Escherichia coli 40 (32.8%) followed by Klebsiella pneumoniae 24 (19.7%) and Enterobacter aerogenes 14(11.5%). Most of the CPE isolates were isolated from wound swab 40(32.8), sputum 33(27.0), and urine 22(18.0) samples. Furthermost strains showed high resistance rates (>70%) to the antibiotics tested. Resistance to amikacin, tetracycline, co-trimoxazole, and nalidixic acid was 36.9%, 43.4%, 62.3%, and 63.9%, respectively and 82.8 % of CPE strains were susceptible to colistin. The detection of blagenes carbapenemases in CPE strains had a significant effect on both imipenem and meropenem MICs. Conclusion. The most prevalent carbapenemase-producing blagenes among clinical Enterobacteriaceae clinical isolates from the three Khartoum state regions were blaIMP, blaNDM, and blaOXA-48. In contrast, the propensity of the multidrug-resistant profile that has been associated with producing carbapenemase blagenes is alarming. Therefore, it is very important to establish a routine screening of carbapenemase-producing blagenes in clinical isolates to prevent the dissemination of resistant strains among both inpatients and outpatients in hospital settings.