Abstract: | Abstract Infection with hepatitis C virus (HCV) has become the most important public health problem in Egypt. HCV infection has been implicated in diseases of the central nervous system. Cerebrospinal fluid (CSF) and serum samples from 91 patients with meningitis (62 males and 29 females, mean age of 37 years) were investigated. Anti‐HCV antibodies and HCV antigen were evaluated in patients CSF and serum using enzyme linked immunosorbent assay. The levels (mean?±?SD?pg/ml) of Th1 cytokines (IFN‐γ and TNF‐α) and Th2 interleukines (IL‐10 and IL‐4) were also determined. The anti‐HCV antibodies were detected in high percentages both in CSF samples (71%) and in sera (90%). Also, the HCV antigen was detected in about 60% of tested CSF and serum samples. The levels of IFN‐γ and IL‐10 cytokines were significantly higher (P?0.05) in both serum and CSF of patients positive for HCV antigen than those negative. HCV antigen was detected in the CSF of meningitis patients with a significant upregulation of Th1 and Th2 responses. The high incidence of HCV infection may draw light on the etiological role of HCV in the pathogensis of meningitis diseases in our study group. |