ABSTRACT
BACKGROUND: Though animal studies have suggested a role for proinflammatory cytokines in pathogenesis their exact role in pathogenesis of human meningeal tuberculosis continues to be controversial with different studies yielding contradictory results. AIM AND OBJECTIVES: To study the levels of proinflammatory cytokines in serum and cerebrospinal fluid (CSF) of patients with tubercular meningitis (TBM) and to determine whether these correlate with disease severity. PATIENTS AND METHODS: Present study included 146 patients with TBM (90- Definite TBM; 56- Probable TBM), diagnosed according to criteria laid by Ahuja et al. which were modified to include CSF nucleic acid based tests. Serum (n=146) and CSF (n=140) levels of various proinflammatory cytokines (IL-1ß, IL-2, IL-6, TNF-α and IFNγ) were compared between TBM patients and healthy volunteers (n=99). These levels were correlated with various clinical, radiological and CSF parameters of TBM patients. RESULTS: Proinflammatory cytokines include cytokines which promote systemic inflammation. In current study, the serum and CSF levels of various cytokines (IL-2, IL-4, IL-6, IL-1ß, IFN-γ and TNF-α) were significantly elevated in TBM patients compared to controls. A significant correlation was found between a) Higher stage of TBM and various cytokines (except for serum IL-6 and CSF IFN-γ); b) High CSF TNF-α, IL-4 and IL-1ß with severity of hydrocephalus; c) High CSF IL1ß and IFN-γ with presence of exudates on MRI; d) Serum and CSF levels of all cytokines with poor outcome as determined by death or as defined by S and E ADL (Schwab and England activities of daily living) score or by GOS (Glasgow outcome scale) (except for interferon gamma); and e) Serum and CSF IL-4 and IL1ß with presence of infarcts on MRI brain. CONCLUSION: Proinflammatory cytokines play an important role in the pathogenesis of TBM and contribute significantly towards severity of disease.
