Positive Bacterial Culture among Lower Respiratory Tract Specimens of Patients in a Tertiary Care Centre: A Descriptive Cross-sectional Study.

Introduction: Lower respiratory tract infection accounts for a great burden of disease worldwide. The problem has further increased due to increasing antimicrobial resistance. This study was done to find out prevalence of positive bacterial culture among lower respiratory tract specimens of patients in a tertiary care centre.

Methods: A descriptive cross-sectional study was done in the Laboratory of Clinical Microbiology in a tertiary care centre from May, 2021 to October, 2021. Ethical approval was received from the Institutional Review Committee (Reference number: 045-077/078). A total of 635 specimens were collected by convenience sampling. The specimens were cultured as per standard microbiological techniques. Antibiotic susceptibility was performed following Clinical and Laboratory Standards Institute (2020) guidelines. Microsoft Excel was used for data entry and analysis. Point estimate at 95% Confidence Interval was calculated along with frequency and proportion.

Results: Among the 635 lower respiratory specimens, 112 (17.63%) (111.97 to 112.03 at 95% Confidence Interval) showed positive bacterial culture. Klebsiella pneumoniae 44 (37.93%) was the commonest isolate followed by Acinetobacter calcoaceticus baumannii complex 34 (29.31%).

Conclusions: The prevalence of positive bacterial culture among lower respiratory specimens was lower when compared to other studies done in similar settings.

Keywords: antibiotic resistance; gram negative bacteria; respiratory tract infections.