Etiologies, Risk Factors, and Antibiotic Pattern of Lower Respiratory Tract Infection in Patients Coming to Deccan College of Medical Sciences, Hyderabad, South India

Background: Lower Respiratory Tract Infections (LRTI) impose a huge problem on society due to their tenacious and un-escapable health problems, and they were the reasons for consultation and hospitalization. Patients with LRTI were present with a wide spectrum of diseases that range from life-threatening infections to minor self-limiting illnesses.

Materials and methods: Sputum samples from 310 patients with complaints of lower respiratory tract infections were collected and analyzed. After microscopic analysis, 30 were excluded from the study. Of the 280 that were included in the study, 171 were males and 109 were females. The age group between 56 and 65 years comprised the highest number of patients in the study. Different antibiotics were used to check antibiotic sensitivity patterns against isolated Gram-positive and negative bacteria.

Results: Of the 280 samples processed, 122 (43.5%) were culture-positive. Among the 122 bacterial isolates, the predominant organism was Klebsiella pneumoniae 55 (45%). The most common predisposing factor identified in 115 (37%) patients was smoking. Using the Double Disk Synergy Test, 11 (20%) out of a total of 55 K. pneumoniae isolates and 4 (30.7%) out of 13 Pseudomonas isolates showed Extended Spectrum Beta Lactamases (ESBL). The Klebsiella and Pseudomonas isolates showed resistance to 2nd and 3rd generation Cephalosporins.

Conclusion: Because of different geographical regions and conditions, the etiology and the antibiotic sensitivity patterns of LRTI vary, so the etiology, predisposing factors, and the antibiotic sensitivity pattern of LRTI need to be updated regularly. The diagnostic facilities for early and rapid identification of LRTI also need to be improved.