The immunopathogenesis of occult hepatitis C virus (HCV) infection is a matter of great controversy and has been suggested to involve a complex balance between cytokines with proinflammatory and anti-inflammatory activity. This work aimed at studying the production of serum Th1 and Th2 cytokines in patients with occult HCV infection.
Serum levels of cytokines Th1 [interleukin-2 (IL-2) and interferon-γ (IFN-γ)] and Th2 (IL-4) were measured in 27 patients with occult HCV infection and in 28 patients with chronic hepatitis C infection.
The levels of IL-2 and IFN-γ were highly significantly increased in patients with chronic HCV infection (P<0.001). In contrast, IL-4 showed a highly significant increase in occult HCV infection (P<0.001). Significant increases were noted in chronic HCV infection with respect to bilirubin (P<0.001), alanine transaminase (P=0.009), aspartate transaminase (P=0.013) and alfa-fetoprotein (P<0.001) levels, whereas the level of serum albumin was significantly higher in occult HCV infection (P<0.001). The degree of necroinflammation (P<0.001), fibrosis (P<0.001) and cirrhosis (P=0.03) was significantly increased during chronic HCV infection.
Our data revealed a high prevalence of occult HCV infection (25%) in patients with unexplained persistently abnormal liver function test results. These patients exhibited a distinct immunoregulatory cytokine pattern, favouring viral persistence and explaining the less-aggressive course of this disease entity compared with chronic HCV infection.
Departments of aInternal Medicine
eClinical Microbiology, Mansoura University, Mansoura, Egypt
Correspondence to Yahia Z. Gad, Department of Internal Medicine, Mansoura University, Mansoura, Egypt E-mail: firstname.lastname@example.org
Received December 15, 2011
Accepted December 20, 2011