Study of the Serum Levels of C-Reactive Proteins as an Indicator of Disease Activity in Pulmonary Tuberculosis and Monitoring Response to Treatment.

ABSTRACT

Background: Pulmonary Tuberculosis is caused by mycobacterium tuberculosis. C-reactive proteins (CRP) are produced in the body by liver in response to inflammation caused by Mycobacterial infection. Insufficient information is available in medical literature, correlating serum CRP levels to the severity of pulmonary tuberculosis. The present study was undertaken to correlate the validity of serum CRP levels to clinical findings. Severity of pulmonary tuberculosis, need for ventilator support, response to anti-tubercular therapy and mortality. Objectives: To correlate the serum CRP levels with clinical findings, mortality, radiological severity and response to anti-tubercular treatment in patients suffering from pulmonary tuberculosis. Methods: The present study was conducted in 50 new sputum positive pulmonary TB patients and 50 healthy individuals. The patients were evaluated for clinical and radiological findings, which were correlated to baseline CRP levels. CRP levels were measured at 2 months and after completion of treatment and correlated to treatment end results. Results: Mean baseline CRP levels in pulmonary tuberculosis patients were 55.32mg/L (range 16- 144mg/L).CRP levels among normal healthy individuals were 4.46 mg/L (range 2-8mg/L). CRP levels were significantly higher in TB patients with fever, tachycardia, tachypnea, hypotension, respiratory distress and the need for ventilatory support when compared to patients without these features. The study showed significant correlation between CRP levels and radiological extent of disease. Baseline CRP levels were significantly higher in mortality group when compared to survivor group.CRP levels showed progressive decline in patients who were cured. Conclusion: The CRP levels in pulmonary tuberculosis patients before initiating anti-tubercular therapy showed a positive correlation with features like presence of fever, tachycardia, tachypnea, hypotension, respiratory distress, need for ventilator support, radiological severity and in patients who died. Thus, serum CRP levels can be used as a surrogate marker for severity of pulmonary tuberculosis in the patients. This is probably the first study conducted in North India correlating CRP levels and disease severity of pulmonary Tuberculosis to the best of our knowledge.