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Dr. Kaneriya Maulik
Dr. Smita Trivedi
Dr. Shailee Patel
Dr. Bhutiya Malde
Dr. Parth Jakasaniya


C-Reactive Protein, Pleural Effusion, Exudates, Transudates, Leukocytes


Background and Objectives: Exudative pleural effusion is a common clinical problem with various underlying causes. This study aimed to assess the diagnostic utility of pleural fluid C-reactive protein (CRP) in differentiating between the etiologies of exudative pleural effusions, specifically focusing on tuberculous, malignant, and parapneumonic effusions.

Material and Methods: We enrolled 60 patients with exudative pleural effusion diagnosed through clinico-radiological criteria. Sociodemographic and hematological variables were evaluated across the three etiological groups. Additionally, pleural fluid parameters, including CRP, were measured. The study participants were categorized into groups based on the etiology of their effusions as malignant, parapneumonic and tubercular effusions.

Results:  Tuberculous effusion was the most common etiology in our study, followed by malignant and parapneumonic effusions. Malignant effusions were more prevalent in older age groups and among males. Hematological variables did not show significant differences between the groups. Total leukocyte counts were higher in parapneumonic effusions. Smoking history was more prevalent among patients with malignant effusions. Co-morbid conditions like hypertension and diabetes did not correlate significantly with effusion etiology. Pleural fluid LDH, ADA, and CRP were elevated in tuberculous effusions compared to malignant effusions.

Conclusion: Pleural fluid CRP levels were notably higher in parapneumonic effusions compared to both tuberculous and malignant effusions. Additionally, CRP demonstrated a significant role in distinguishing between parapneumonic and malignant effusions, as well as between tuberculous and malignant effusions. These findings suggest that pleural fluid CRP can serve as a valuable diagnostic marker in the etiological differentiation of exudative pleural effusions, aiding clinicians in prompt and accurate decision-making for patient care.

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