Abstract
Occult hepatitis C virus (HCV) infection is a new entity that should be considered when diagnosing patients with abnormal liver functions of unknown origin. This work was carried out to evaluate T-helper 1/T-helper 2 (Th1/Th2) cytokine profiles in patients with occult HCV infection versus chronic hepatitis C (CHC) infection, also to investigate any association between theses cytokines and liver histological features in both groups. Serum levels of Th1 cytokines (IL-2, IFN-γ) and Th2 (IL-4 and IL-10) were measured in 35 patients with occult HCV infection compared to 50 patients with chronic hepatitis C infection and 30 healthy controls. We have found that Th1 cytokines were significantly increased in patients with CHC infection than in both occult HCV infection and control groups (p<0.001). On the other hand, serum IL-4 levels were higher in occult HCV infection than in CHC and control groups (p<0.001). Furthermore, serum IL-10 levels were higher in both patient groups vs control group (p<0.001), with no significant difference between CHC and occult HCV groups. Finally, only serum IL-10 levels were significantly higher among patients with high activity (A2-A3) than those with low activity (A0-A1) in both CHC and occult HCV groups (p=0.038, p=0.025, respectively). Patients with occult HCV infection exhibited a distinct immunoregulatory cytokine pattern that is shifted towards the Th2 arm.