https://doi.org/10.4081/monaldi.2025.3161

Frequency of viral etiology in community-acquired pneumonia

Early Access
Submitted: July 31, 2024
Accepted: January 7, 2025
Published: January 17, 2025
Pneumonia, etiology, outcome, mortality, Pakistan
Abstract Views: 614
PDF_EARLY VIEW: 187
SUPPLEMENTARY MATERIAL: 15
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Authors

Zain Ahmad Khan
Section of Pulmonary and Critical Care, Department of Medicine, Aga Khan University, Karachi, Pakistan.
Akbar Shoukat Ali
https://orcid.org/0000-0002-3654-6051
Section of Pulmonary and Critical Care, Department of Medicine, Aga Khan University, Karachi, Pakistan.
Imran Ahmed
Section of Microbiology, Department of Pathology and Laboratory Medicine, Aga Khan University, Karachi, Pakistan.
Joveria Farooqi
https://orcid.org/0000-0002-9921-4660
Section of Microbiology, Department of Pathology and Laboratory Medicine, Aga Khan University, Karachi, Pakistan.
Muhammad Irfan
muhammad.irfan@aku.edu
https://orcid.org/0000-0002-5796-2548
Section of Pulmonary and Critical Care, Department of Medicine, Aga Khan University, Karachi, Pakistan.

The identification of etiology is very important when managing patients with community-acquired pneumonia (CAP). In Pakistan, studies regarding the viral etiology in CAP are scarce. The main objective of this study was to evaluate the frequency of viral etiology in CAP patients and analyze the clinical features and their impact on prognosis. Medical records of CAP patients admitted to Aga Khan University Hospital (Karachi, Pakistan) from March 2022 to February 2023 were retrospectively reviewed, patients who had microbiological tests performed within 48 hours of the hospital admission were included, and the frequency of viral and bacterial etiology was calculated. Patients who were immunocompromised were excluded. Epidemiological and clinical characteristics were examined, and the impact on prognosis was explored. A total of 166 patients were included; 115 (69.3%) patients were identified as having pneumonia with known causative microorganisms. A total of 83 (72.1%) patients had a viral etiology alone, 18 (15.6%) had only bacterial infection, and 14 (12.2%) had a viral and bacterial co-infection. Influenza A was most frequently detected (n=46/97; 47.4%), followed by Rhinovirus/Enterovirus (n=19/97; 19.6%). Staphylococcus aureus accounted for the majority (n=18; 56.3%) of cases among bacteria. Bacterial and viral-bacterial co-infection was significantly higher among non-survivors (38.1% vs. 16.6%, p=0.034). Confusion-Urea-Respiratory Rate-Blood Pressure-Age of 65 scores of 3-5 [odds ratio (OR) 4.234; 95% confidence interval 1.156-15.501], leukocytosis (OR 0.137; 0.030-0.636), high C-reactive protein (>10mg/L) (OR 1.008; 1.001-1.014), high serum procalcitonin level (≥0.5 ng/mL) (OR 10.731; 3.018-38.153), and mechanical ventilation required (OR 47.104; 13.644-162.625) were associated with mortality. Mechanical ventilation requirement was independently associated with increased odds of mortality (OR 43.407; 8.083-233.085). Of 166 patients, 21 (12.7%) had died, with the highest percentage (28.6%) seen in the viral-bacterial coinfection group (p=0.046). To conclude, respiratory viruses are increasingly being recognized as an important etiology in CAP, with higher mortality seen in bacterial infection, whether alone or with viral co-infection.

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Ethics Approval

Given the retrospective chart reviews and lack of direct involvement of patients or other human participants, a waiver of ethics approval and informed consent was obtained from the Ethics Review Committee (ERC) of the Aga Khan University (ERC #2023-8526-24641).

How to Cite

Khan, Zain Ahmad, Akbar Shoukat Ali, Imran Ahmed, Joveria Farooqi, and Muhammad Irfan. 2025. “Frequency of Viral Etiology in Community-Acquired Pneumonia”. Monaldi Archives for Chest Disease, January. https://doi.org/10.4081/monaldi.2025.3161.
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