Oral lichen planus in patients infected or noninfected with hepatitis C virus: the role of autoimmunity

Serum proteins, serum immunoglobulins, anti‐nuclear antibodies (ANA), antismooth muscle antibodies (ASMA), anti‐mitochondrial antibodies (AMA), anti‐liver‐kidney antibodies (LKM), anti‐parietal‐cell gastric antibodies (APCA), anti‐epithelial antibodies and concomitant autoimmune disease were studied in 27 OLP‐HCV+ve subjects and in a comparable group of 23 who were OLP‐HCV‐ve. In addition, all the patients with chronic liver disease who were seropositive for ANA, AMA or LKM were scored using the new aggregate scoring system to detect those with the accepted criteria for the diagnosis of autoimmune hepatitis (AIH). Hypergammaglobulinemia was more frequent in OLP‐HCV+ve than in OLP‐HCV‐ve (P=0.008) subjects. Serum IgG and IgM levels were higher in HCV+ve than in HCV‐ve (respectively, P=0.017 and P=0.018) individuals. However, there was no difference in the frequency of any autoantibody between OLP‐HCV+ve and OLP‐HCV‐ve patients. Overall, immunologically‐related abnormalities were found in 17(63%) OLP‐HCV+ve and 11(48%) OLP‐HCV‐ve (P=0.43) patients. Three OLP‐HCV‐ve and no OLP‐HCV+ve patients had score criteria of probable AIH. The present and our previous data suggest that OLP patients with HCV infection neither had evidence of autoimmune liver damage nor had abnormal humoral immune‐responses, with the exception of higher than control levels of serum immunoglobulins. Cryoglobulins may be responsible.