Antibiotic susceptibility patterns of pathogens isolated from laboratory specimens at Livingstone Central Hospital in Zambia.

Abstract

BackgroundMultidrug resistance (MDR) is a global problem that require multifaceted effort to curb it. This study aimed to evaluate the antibiotic susceptibility patterns of routinely isolated bacteria at Livingstone Central Hospital (LCH).MethodsA retrospective study was performed on all isolated organisms from patient specimens that were processed from January 2019 to December 2021. Specimens were cultured on standard media and Kirby-Bauer disc diffusion method was employed for susceptibility testing following the Clinical and Laboratory Standard Institute's recommendations.ResultsA total of 765 specimens were processed and only 500 (65.4%) met the inclusion criteria. Of the 500, 291(58.2%) specimens were received from female and from the age-group 17-39 years (253, 50.6%) and 40-80 years (145, 29%) in form of blood (331, 66.2%), urine (165, 33%) and sputum (4, 0.8%). Amongst the bacterial isolates, Staphylococcus aureus (142, 28.4%) was the commonest followed by Escherichia coli (91, 18.2%), and Enterobacter agglomerans (76, 15.2%), and Klebsiella pneumoniae (43, 8.6%). The resistance pattern revealed ampicillin (93%) as the least effective drug followed by oxacillin (88%), penicillin (85.6%), co-trimoxazole (81.5%), erythromycin (71.9%), nalidixic acid (68%), and ceftazidime (60%) whereas the most effective antibiotics were imipenem (14.5%), and piperacillin/tazobactam (16.7%). The screening of methicillin resistant Staphylococcus aureus (MRSA) with cefoxitin showed 23.7% (9/38) resistance.ConclusionIncreased levels of MDR strains and rising numbers of MRSA strains were detected. Therefore, re-establishing of the empiric therapy is needed for proper patient management, studies to determine the levels of extended spectrum beta lactamase- and carbapenemase-producing bacteria are warranted.