Antimicrobial Resistance Trends for Bacterial Organisms in Mater Misericordiae Hospital, Nairobi, Kenya (2020 – 2022)

Abstract

Background: Antimicrobial resistance is a growing menace and a global public health threat. Cumulative antibiograms are useful for monitoring the trends of antimicrobial resistance patterns. However, there is a paucity of data in Kenya that examines the trends of antimicrobial resistance. Objective: To determine antimicrobial susceptibility trends of bacterial pathogens isolated over the 3 years (2020-2022) among patients who received treatment, including methicillinresistant Staphylococcus aureus (MRSA), extended-spectrum beta-lactamase (ESBL) producing bacteria, carbapenem-resistant Enterobacteriaceae (CRE) and other carbapenemresistant organisms (CRO), aminoglycoside and fluoroquinolone-resistant organisms. Methodology: This was a retrospective descriptive survey of antimicrobial resistance trends from clinical isolates from 2020 to 2022. Four hundred (400) medical records of patients treated at Mater Misericordiae Hospital for various bacterial infections were reviewed. Data was obtained using a standard data collection form and later keyed into REDCap Software, to capture information on the date of specimen collection, type of specimen collected (blood, urine, sputum, cerebrospinal fluid, broncho-alveolar lavage, endotracheal secretions, intraabdominal fluids, and others), Bacterial isolates that were clinically relevant were obtained using standard laboratory techniques. Standard operating procedures for identification of pathogens and interpretation of antimicrobial susceptibility tests were as per CLSI 2022 guidelines. The VITEK-2 compact system (bioMerieux) performed identification and susceptibility testing with Advanced Expert System (AES). Employed SPSS version 25 to compute descriptive statistical parameters such as frequency, mean, mode, and median to summarize the findings. The null hypotheses stated: The occurrence and trend of the occurrence of bacterial isolates are the same over the study period, with no difference in the patterns of resistance of MRSA, ESBL, CRE, aminoglycoside, and fluoroquinolone resistance in the past 3 years and antimicrobial agents have no increased resistance from bacterial pathogens in the past 3 years. Alternative hypotheses stated: Certain bacterial isolates tend to occur more than their counterparts, there are varying trends in the occurrence of bacterial isolates over the study period, there is a difference in the patterns of resistance of MRSA, ESBL, CRE, aminoglycoside and fluoroquinolone resistance in the past 3 year and antimicrobial agents have increased resistance from bacterial pathogens in the past 3 years Results: Medical records of patients with bacterial infections at Mater Misericordiae Hospital

were obtained. Of the 400, 114 (28.5%) had received treatment in 2020, 121 (30.3%) in 2021, and 165 (41.3%) in 2022. Cultures collected from different sanctuary sites of infection: urine, blood, respiratory samples (broncho-alveolar lavage and endotracheal secretions, tracheal aspirates, pleural fluid, bronchial wash, sputum) and swabs (pus, high vaginal, urethral, ear, stromal, nasal, throat, and tissue), skin and related structures, stool, tissue samples, CSF, biliary fluid, peritoneal fluid, renal fluid and semen. Urine and blood contributed most of the growth. Four hundred and seven (407) isolates were identified representing 36 different specific bacterial organisms. Majority of the isolates being E.coli (160, 40%), K. pneumoniae (83, 20.8%), S. aureus (40, 10.0%), P. aeruginosa (16, 4.0%) and Enterococcus faecalis (14, 3.5%). Two hundred and forty-two (242) out of 407 bacterial isolates mounted resistance to at least one antimicrobial agent corresponding to 27 out of 36 specific bacterial organisms showing general antimicrobial resistance. Over the 3 years, MRSA were 5 out of 17 S. aureus isolates (29.4%), ESBL-producing organisms were 147 out of 186 (79%), CRE were 14 out of 171 (8.2%), CRO: P. aeruginosa were 3 out of 9 (33.3%) and A. baumanii resistant isolates were 5 out of 5 (100%), fluoroquinolone-resistant organisms were 92 out of 242 (38%) and aminoglycoside resistant organisms were 37 out of 99 (18.6%). Overall, there were decreasing antimicrobial resistance trends: ESBL (decreasing by -8.52% per year) despite the rising numbers of ESBLproducing organisms over the 3 years; CRE (decreasing by -1.15% per year), fluoroquinolone (decreasing by -1.23% per year), aminoglycoside (decreasing by -6.42% per year), MRSA (decreasing by -13.89% per year), carbapenem-resistant P. aeruginosa (decreasing by -25% per year) and carbapenem-resistant A. baumanii (Neutral, 0%). Increased antimicrobial resistance from bacterial pathogens from 2020 to 2022 included: 3rd and 4th generation cephalosporins, piperacillin-tazobactam from Enterobacteriaceae: E.coli, K.pneumoniae (ESBL-producing organisms), ciprofloxacin from E.coli (fluoroquinolone-resistant organisms), gentamicin from E.coli (aminoglycoside-resistant organism), meropenem and cefepime from A.baumanii (carbapenem-resistant organism and ESBL-producing organism, respectively). P.aeruginosa had low resistance rates to 3rd and 4th generation cephalosporins and meropenem. E.faecalis had low resistance rates to penicillins and cephalosporins. Conclusion: Regular antimicrobial resistance surveillance needs to be done and further molecular studies to analyze the resistant bacterial pathogens