A study of clinical and etiological profile of community‑acquired pneumonia with special reference to atypical pneumonia

Abstract

Background: Pneumonia is a leading cause of morbidity and mortality, especially in developing countries. The cause of community‑acquired pneumonia (CAP) is often difficult to establish. The most effective methods, especially for the diagnosis of atypical pathogens, are often invasive and may not always be justified. We studied the clinical and etiological profile of CAP, especially with regards to pathogens causing atypical pneumonia.

Aims and Objectives: The aim is to study the clinical profile and etiological agents in patients suffering from CAP in our hospital and to detect proportion of atypical pathogens among these CAP patients.

Methodology: From September 2012 to September 2014, 122 patients were diagnosed as having CAP and were included in this study. After sputum, blood culture, and serological evaluation, they were grouped as having typical and atypical pneumonia. Chi‑square test was used as statistical method to compare between these two groups.

Results: Of 122 patients, 40.2% of patients were found to have typical organisms and 20.5% had atypical organisms causing pneumonia. The common etiological agents were Streptococcus pneumoniae (15.6%) and Klebsiella pneumoniae (8.2%) among typical pneumonia and Mycoplasma pneumoniae (7.4%) and Legionella pneumophila (5.7%) among atypical pneumonia cases.

Conclusions: It is difficult to differentiate these causative agents by clinical features alone. Hence, appropriate serological, sputum, and blood culture should be carried out for early diagnosis, prompt treatment and also to reduce complications.

Keywords: Community‑acquired pneumonia, etiology, indirect immunofluorescence, typical and atypical pathogens