EVALUATION OF SERUM C-REACTIVE PROTEIN AND INTERLEUKIN-6 LEVELS IN NEWLY DIAGNOSED PULMONARY TUBERCULOSIS PATIENTS BEFORE AND AFTER ANTI-TUBERCULAR THERAPY

Background: Tuberculosis (TB), caused by Mycobacterium tuberculosis, continues to be a major public health burden, particularly in highincidence countries like India. Despite the availability of effective treatments, diagnostic limitations—especially in sputum-scarce cases—hamper early detection and disease control. Inflammatory biomarkers such as C-reactive protein (CRP) and interleukin-6 (IL-6) have emerged as promising adjuncts in TB diagnosis, prognosis, and treatment monitoring. Objective: To estimate baseline levels of serum CRP and IL-6 in newly diagnosed sputum-positive pulmonary tuberculosis (PTB) patients and assess their dynamic changes following anti-tubercular therapy (ATT) in accordance with National Tuberculosis Elimination Programme (NTEP) guidelines. Methods: This prospective study was conducted at PGIMS, Rohtak, on 50 newly diagnosed sputum-positive PTB patients. Serum high-sensitivity CRP and IL-6 levels were measured at diagnosis, after 2 months (intensive phase), and after 6 months (continuation phase) of standard ATT. Exclusion criteria included extrapulmonary TB, drug resistance, HIV co-infection, prior ATT, and major comorbidities. IL-6 was quantified using a Diaclone ELISA kit. Clinical, radiological, and laboratory data were collected and analyzed using appropriate statistical methods, with p<0.05 considered significant. Results: The mean age of patients was 42.64±19.01 years, with a male-to-female ratio of 1.9:1. Key symptoms included cough and anorexia (100%), dyspnea (92%), weight loss (86%), and fever (80%). Baseline CRP and IL-6 levels were markedly elevated in all patients. Significant reductions in both markers were observed at 2 and 6 months post-treatment initiation, correlating with clinical improvement and radiological resolution. Higher baseline CRP was associated with delayed sputum conversion and more extensive radiological findings. HRCT revealed lymphadenopathy in all patients, and nodular or consolidative changes were common. Risk factors such as smoking, alcohol intake, and low BMI were prevalent in the cohort. Conclusion: CRP and IL-6 levels are significantly elevated in active PTB and decline with effective anti-tubercular therapy. These markers can serve as reliable adjuncts for disease monitoring and may aid in assessing treatment response, especially in settings where conventional diagnostics are limited. Further large-scale studies are warranted to validate their prognostic utility