Establishment of elevated serum levels of IL-10, IL-8 and TNF-beta as potential peripheral blood biomarkers in tubercular lymphadenitis: a prospective observational cohort study

Background: Tubercular lymphadenitis (TL) is the most common form of extra-pulmonary tuberculosis (TB) consisting about 15-20% of all TB cases. The currently available diagnostic modalities for (TL), are invasive and involve a high index of suspicion, having limited accuracy. We hypothesized that TL would have a distinct cytokine signature that would distinguish it from pulmonary TB (PTB), peripheral tubercular lymphadenopathy (LNTB), healthy controls (HC), other lymphadenopathies (LAP) and cancerous LAP. To assess this twelve cytokines (Tumor Necrosis Factor (TNF) -alpha, Interferon (IFN) -gamma, Interleukin (IL)-2, IL-12, IL-18, IL-1beta, IL-10, IL-6, IL-4, IL-1 Receptor antagonist (IL-1Ra), IL-8 and TNF-beta, which have a role in pathogenesis of tuberculosis, were tested as potential peripheral blood biomarkers to aid the diagnosis of TL when routine investigations prove to be of limited value. Methods and Findings: A prospective observational cohort study carried out during 2010-201...