An Observational Study on Etiology of Non-Resolving Pneumonia in a Tertiary Care Hospital of Karachi, Pakistan

Abstract

Background: Non-resolving pneumonia (NRP) is a disease process of lung parenchyma that lacks significant symptomatic improvement and/or has less than 50% resolution by 2 weeks or incomplete resolution by 4 weeks despite appropriate antimicrobial therapy (generally considered to be of 10-14 days duration). Studies suggest that NRP may account for 10-15% of nosocomial pneumonias, 15% of inpatient pulmonary consultations, and 8% of bronchoscopies done in a tertiary caresetting. The present study was conducted with the objective of the study was to delineate the various causes of NRP as well as its association with patient characteristics, radiographic characteristics, and clinical outcome Objective: The objective of the study was to delineate the various causes of NRP as well as its association with patient characteristics, radiographic characteristics, and clinical outcomes. Methodology:   This was a descriptive retrospective observational study. Data was collected from September 2019 to January 2021. Overall, 29 outpatient files coded as NRP and 237 inpatient files labeled as pneumonia were reviewed. Of these, 33 patients met the eligibility criteria and were systematically assessed with regards to study objective. Results: Average age at NRP diagnosis was 55.15±18 years. Smoking was a significant comorbidity in 48% of patients. Regarding radiographic imaging, no associations were observed. Sputum cultures demonstrated 33% positivity, whereas lung biopsies successfully identified the underlying etiology in all those who underwent this procedure. Tuberculosis (40.1%), malignancy (21.2%), and Aspergillus lung disease (18%) were the most common causes of NRP. Excluding those who lost to follow up and died, every patient had complete symptomatic recovery, and 96% radiographic resolution within 6 months of initiation of treatment was noted. Conclusion: This study stresses that biopsy serves as the gold standard for NRP diagnosis. Moreover, although the diagnosis of NRP may be challenging, treatment is certainly possible. Key words: Non-resolving pneumonia; Etiology; Tuberculosis; Aspergillus; Lung biopsy