Soluble Interleukin-2 Receptor Alpha (siL-2Ra) and Neopterin In Patients With Pulmonary Tuberculosis

1Mabrouk Ghonaim, 2Rawhia El-Edel and 3Ahmed Rabie El-Arbagy

Departments of 1Microbiology and Immunology, 2Clinical pathology and 3Internal Medicine Faculty of Medicine, Menoufiya University, Egypt.

Soluble interleukin-2 receptor alpha (sIL-2Ra) is a marker of T lymphocyte activation, while neopterin is a marker for the activation of the monocyte/ macrophage axis. In this study, serum levels of sIL-2Ra and neopterin were determined in patients with pulmonary TB to assess their relation to the clinical, and laboratory parameters of disease activity and the effect of treatment on their levels. The study included 44 patients with active pulmonary TB, 6 patients with inactive disease and 20 controls. diagnosis was based on clinical, radiological and laboratory assessment (including chest X-ray, ESR, C-reactive protein (CRP), tuberculin testing and examination of sputum for tubercle bacilli). sIL-2Ra and neopterin were determined by enzyme immunoassay and radioimmunoassay respectively. Results showed a significant (p< 0.001) elevation of sIL-2Ra level in TB patients with active disease (1253 ± 492 pg/ml) as compared to controls (412 ± 173 pg/ml). The neopterin level was also higher in active TB patients (45.8 ± 17.1 nmol/L) than controls (5.2 ± 1.8 n mol/L). Patients with active disease showed significantly (p< 0.001) higher levels of both sIL-2Ra and neopterin as compared to those with inactive disease. Moreover, TB patients with extensive lesions showed significantly (p< 0.001) higher levels compared to those with localized lesions. On the other hand, there was no significant difference between patients with cavitation or pleurisy and those without. However, there was a significant (p< 0.01) positive correlation of both sIL-2Ra and neopterin with ESR and CRP values, and a significant (p< 0.001) decline of both of them after 2 months of antituberculous chemotherapy as compared to their levels before treatment. In conclusion, sIL-2Ra and neopterin serum levels are increased in patients with pulmonary TB and can be used as markers for disease activity and follow up of antituberculous treatment.