Assessment of serum levels of anti-gliadin (IgA and IgG) antibodies in patients with lichen planus: A pilot study.

Despite the fact that anti-gliadin antibodies (AGA) play a key role in coeliac disease (CD) screening, elevated AGA levels have been reported in several immune-mediated cutaneous conditions even in the absence of gastrointestinal disease clinical manifestations. A gluten-free diet led to improvements in some of these disorders. The link between oral lichen planus (LP) and CD was revealed, but there is currently no information available regarding the association between cutaneous LP and gluten sensitivity. This study aimed to assess the AGA (IgA and IgG) serum levels in LP patients compared to controls and to determine their correlation with LP severity. The study included 20 patients with cutaneous LP and 20 age- and sex-matched controls, both free of CD manifestations. The enzyme-linked immunosorbent assay (ELISA) technique was utilized for the evaluation of AGA (IgA and IgG) serum levels. Hepatitis C virus (HCV) antibodies in LP patients were evaluated qualitatively using a chromatographic immunoassay. In LP patients, AGA (IgA and IgG) serum levels were significantly elevated compared to controls (p = 0.015 and p=0.016, respectively). A significant positive correlation between AGA (IgG) serum levels and the age of patients (p= 0.024), duration of disease (p= 0.02), and LP severity index (p< 0.0001) was found. AGA serum levels were insignificantly different between HCV-positive and HCV-negative LP patients (p= 0.054). In conclusion, the significant elevation of serum AGA levels in LP patients reflects a possible link between LP and occult CD. Serum AGA (IgG) levels can be used as a marker of LP severity..