Diagnostic importance of C-reactive protein [CRP] analysis in tuberculosis pleural effusions

ABSTRACT

One of the acute-phase biomarkers that have recently been investigated for its clinical utility in tuberculosis pleural effusion is C-reactive protein [CRP] which has already been commonly used as a marker of inflammation and tissue injury. Therefore, the present study was undertaken to analyze the viability of CRP as a diagnostic aid for tuberculosis in lymphocytic pleural effusions. Fifty two [n = 52] patients with lymphocytic pleural effusion with definite diagnosis of a disease condition, were taken into the test group and classified into no tuberculosis [n = 28] group and tuberculosis pleurisy group where sputum culture was positive for Mycobacterium tuberculosis in pleural effusion [n = 24]. CRP in pleural fluid was analyzed by automated turbid metric immunoassay method as per description of the manufacturer and normal reference value in serum ispleural effusion in control group is = 20.45 mg/L. Twenty four patients [males = 19; Female = 5] were diagnosed with tuberculosis whereas 9 with pulmonary embolism, 5 with CABG and 14 with benign exudates of para-pneumonic origin. CRP of non-tuberculosis effusions were noted to be relatively lower in levels [range 15.30 +/- 5.10 to 32.10 +/- 9.25 mg/L] as compared to those obtained in tuberculosis effusions [62.50 +/- 12. 75 mg/L]_ However, CRP of benign exudates of para-pneumonic origin showed a higher value, 32.10 +/- 9.25 mg/L, than other non-tuberculosis effusions. The level of significant difference was high with P<0.001 when CRP of tuberculosis pleural effusion was compared with non-tuberculosis effusions, whereas with para pneumonic exudates, the difference was moderately significant, P<0.01. The results clearly indicates a significant role of CRP for diagnostic facilitation of tuberculosis pleural effusion in comparison with non-tuberculosis effusions of para-pneumonic, CABG or pulmonary dysfunctions