Common Pathogens and Their Resistance to Antimicrobials in Community Acquired Pneumonia (CAP): A Single Center Study in Bangladesh

Abstract

Pneumonia is a worldwide, serious threat to health and an enormous socio-economic burden for health care system. Community-acquired pneumonia (CAP) is associated with a significant mortality and morbidity. Knowledge of predominant microbial patterns in CAP constitutes the basis for initial decisions about empirical antimicrobial treatment. The aim of this study was to identify the bacterial etiology of CAP in adult hospitalized patients and to see their antibiotic sensitivity pattern. It was a hospital based cross sectional observational study on 87 hospitalized patients diagnosed with CAP admitted in Medicine department of Chittagong Medical College Hospital (CMCH). Sputum for Gram staining, Z N staining, culture sensitivity, blood culture and sensitivity and PCR for Legionella pneumophila, Mycoplasma pneumoniae, Chlamydophila pneumonia and Streptococcus pneumonia were done. Patients were followed up for in-hospital outcome and 30-day mortality. The mean (±SD) age was 49.59±16.97 years and male female ratio was 1.56:1. Sputum culture, blood culture and PCR were positive in 60.9%, 1.1% and 4.6% of the samples respectively. Klebsiella pneumoniae was identified in the sputum culture of the majority of the patients (39.1%), followed by Pseudomonas aeruginosa (10.3%), Staphylococcus aureus and Escherichia coli (5.7%). The only one sample which was positive in blood culture and it was Staphylococcus aureus. Streptococcus pneumoniae was identified in all the 4 PCR positive cases. The highly sensitive drugs were meropenem, levofloxacin and amikacin. In hospital mortality and 30-day mortality was 6.9% and 16.1% respectively. Gram-negative bacteria pre-dominate in the bacteriologic profile of CAP using conventional sputum and blood culture. There is need for further conventional serologic tests for atypical and viral pathogens in all patients admitted with CAP.