BACTERIOLOGICAL SPECTRUM AND ANTIBIOGRAM OF SPUTUM ISOLATES IN A TERTIARY CARE CENTRE

Background: Lower respiratory tract infections (LRTIs) are an important cause of morbidity, and increasing antimicrobialresistance poses challenges to their management. Identification of bacterial pathogens and their antimicrobial susceptibilitypatterns is essential for appropriate treatment. The objective is to determine the bacteriological spectrum of sputum isolatesand evaluate their antimicrobial susceptibility patterns and the occurrence of multidrug-resistant (MDR) isolates in a tertiarycare centre. Materials and Methods: A hospital-based observational study was conducted over six months at the Departmentof Microbiology, Viswabharathi Medical College, Kurnool, Andhra Pradesh. A total of 340 sputum samples submitted forbacteriological investigation were processed using routine laboratory procedures. Bacterial isolates were identified, andantimicrobial susceptibility patterns and reported MDR isolates were analysed using descriptive statistics. Results: Of the 340sputum samples, 75 (22.1%) showed bacterial growth, while 265 (77.9%) were culture negative. Gram-negative bacteriapredominated, accounting for 66 (88.0%) isolates, whereas Gram-positive bacteria accounted for 9 (12.0%). Klebsiellapneumoniae was the most common isolate (33; 44.0%), followed by Pseudomonas aeruginosa (23; 30.7%). Streptococcuspneumoniae and Staphylococcus aureus accounted for 5 (6.7%) and 4 (5.3%) isolates, respectively. Eight MDR isolates werereported, comprising K. pneumoniae (3), Acinetobacter baumannii (2), P. aeruginosa (2) and Enterobacter species (1).Conclusion: Gram-negative bacteria, particularly K. pneumoniae and P. aeruginosa, predominated among sputum isolates.The identification of MDR isolates emphasises the importance of routine sputum culture, antimicrobial susceptibility testingand rational antibiotic use to guide appropriate therapy and support antimicrobial resistance surveillance.