Abstract / Summary
Abstract Background Lower respiratory tract infections are among the leading causes of illnesses responsible for causing death and adding significant costs to the public health system. Bacteria are the most common causative agents of lower respiratory tract infections. Currently, there is little information on the prevalence, antimicrobial susceptibility patterns, and associated factors of lower respiratory tract infections among adult patients in Ethiopia. Therefore, the objective of this study was to determine prevalence of lower respiratory tract infection, antimicrobial susceptibility profiles and associated factors in the study area. Methods A laboratory-based cross-sectional study was conducted among 376 participants at Nekemte Comprehensive Specialized Hospital from June to September 2024. A structured questionnaire was used to gather sociodemographic and clinical data. Bacterial isolation and identification were done using standard microbiological techniques. The Kirby-Bauer disc diffusion method was used to perform antibiotic susceptibility testing. Data were entered into Epi Data v4.6 and exported to the Statistical Package for Social Science (SPSS) v24 for analysis. Logistic regression analysis was done to assess the association between dependent and independent variables. The strength and significance of the association were determined by adjusted odds ratio (AOR) and p-value ˂ 0.05, respectively. Finally, the results were presented using text, tables, and figures. Result Of 376 sputum samples from adult patients with lower respiratory tract infection, 195 (51.9%) were culture-positive for bacterial pathogens. One hundred ninety-seven bacteria were isolated, with Gram-negative and Gram-positive bacteria accounting for 147 (74.6%) and 50 (25.4%), respectively. Klebsiella pneumoniae (19.8%) was the predominant bacterial isolate, followed by Pseudomonas aeruginosa (17.8%). Gram-negative bacteria were more sensitive to both ciprofloxacin (78.9%) and piperacillin-tazobactam (78.9%), while Gram-positive isolates were sensitive to clindamycin (96.0%). Age, educational status, marital status and occupation had a statistically significant association with lower respiratory tract infections (LRTIs) with a p-value of < 0.05. Conclusion and recommendation: Klebsiella pneumoniae was the predominant isolate of the lower respiratory tract infection pathogen followed by P. aeruginosa . Most isolates of bacteria were resistant to commonly prescribed antibiotics. A significant association was observed with age, educational status, marital status, and occupation. Culture and antibiotic susceptibility testing is essential before treatment to limit the possibility of antimicrobial resistance.