Clinical and Etiological Profile of Community Acquired Pneumonia in a Tertiary Care Centre in South India – A Cross Sectional Study

Background: Several factors play a major role in the natural course of pneumonia unless adequately intervened and few of these include the etiological agent and the risk factors in an individual, such as age and comorbidities. This study was done at a tertiary care institution in South India with an inpatient population that comprised different regions of Kerala, a state in South India which would to an extent, be representative of the community, so as to identify the clinical and etiological profile of CAP. Aims and Objectives: Our study aimed at formulating a clinical profile, etiology, and outcome of patients with community-acquired pneumonia that required inpatient management. Materials and Methods: The population under study included inpatients fulfilling the criteria for community-acquired pneumonia as elucidated in BTS guidelines, admitted at a tertiary care center in South India. A sample size of 160 was studied, and data related to investigations done and organisms isolated was collected retrospectively. A clinical profile was made with age, gender comorbidities, and other risk factors. Investigations ranged from sputum microscopy to the Filmarray Pneumonia panel. Results: Microbial etiology was confirmed in 60% of patients with nasal swabs, sputum, and BAL studies. Influenza A was detected in 69 (43%) cases, followed by Gram negative bacilli in 22 (13.75%) cases and Gram positive organisms in 5 (3%). In 64 (40%) cases, no pathogen was isolated. In bacteria, Klebsiella spp. was isolated in 15 cases, Pseudomonas in 5 cases, Staphylococcus aureus in 2, and Streptococcus pneumoniae in 2 cases. 73 (45%) cases belonged to the elderly age group (>65 years) and 92 (57.5) were male patients. Significant comorbidities were noted in 139 (77%) cases. 9 (5.6%) cases ended up in mortality, of which 8 cases were either elderly with multiple comorbidities (6) or with significant immunosuppression (2). The mortality rate in our study was 5.6%. In 40% of cases, the etiology remained unidentified. Conclusion: Microbial etiology was confirmed in 60% of patients with nasal swabs, sputum, and BAL studies, with the most common causative organism during the study period being Influenza A. The inability to isolate a causative microbe is often attributed to prior use of antibiotics, inadequate sputum production, or nonproductive cough. A complicated hospital course was noted in the elderly age group with multiple comorbidities and those with immunosuppression.