Magnitude and antimicrobial susceptibility patterns of extended-spectrum β-lactamase producing Enterobacteriaceae recovered from environmental samples at Tikur Anbessa Specialized Hospital, Ethiopia

Abstract Background The hospital environment especially the intensive care units (ICUs) contributes to the spread of extended-spectrum β-lactamase (ESBL) producing Enterobacteriaceae, which are contributing to increasing morbidity and mortality rates. We aimed to assess the rate of environmental contamination of ESBL producing Enterobacteriaceae and their antimicrobial susceptibility patterns. Methods A Cross-sectional study was conducted at Tikur Anbessa Specialized Hospital (TASH) from June to July, 2018. A total of 65 environmental swab were taken from inanimate items. All isolates from the inanimate environment were cultured by using ESBL ChromoSelect Agar and identified using conventional bacteriological methods. All ESBL producing Enterobacteriaceae isolates were tested for their antimicrobial susceptibility using the disc diffusion method according to the methods and interpretive criteria of the Clinical and Laboratory Standards Institute (CLSI). Results From a total of 65 environmental swab samples, 16 (24.6%) were ESBL producing Enterobacteriaceae. The most predominant ESBL producing isolates were E. coli (8/16, 50%) and Klebsiella spp (6/16, 37.6%). The Pediatrics and Medical-Surgical ICU exhibited the highest ESBL producing Enterobacteriaceae, each with (37.5%, 6/16). Linens and ventilators were associated with high rates of ESBL isolates positivity each with equal 31.3% detection rate. ESBL producing Enterobacteriaceae isolates had significantly high resistance level to ampicillin (100%), ceftazidime (93.8%), cefepime (87.5%) and cefotaxime (86.7%). However, low resistance level was recorded against amikacin (18.8%). Conclusion The appearance of ESBL producing Enterobacteriaceae among ICUs hospital environment is posing a serious threat for the control of nosocomial infections. The high resistance found from this study shows the need for policies for devising infection control procedures and screening policies for ESBL on a routine basis.