Serological Tests in Gluten Sensitivity (Nonceliac Gluten Intolerance)

Abstract

To characterize the serological pattern of gluten sensitivity (GS) and to compare it with that found in celiac disease. GS has recently been identified as a new clinical entity included in the spectrum of gluten-related disorders, but it is still lacking of diagnostic markers. Sera from 78 patients with GS and 80 patients with celiac disease were retrospectively assessed for immunoglobulin (Ig)G/IgA antigliadin antibodies (AGA), IgG deamidated gliadin peptide antibodies (DGP-AGA), IgA tissue transglutaminase antibodies (tTGA), and IgA endomysial antibodies (EmA). IgG AGA were positive in 56.4% of GS patients and in 81.2% of celiac patients, with high antibody titers in both groups. IgA AGA were detected in 7.7% of GS patients and in 75% of celiac patients, showing lower enzyme-linked immunosorbent assay activities in GS than those found in celiac disease. Only 1 of the 78 patients with GS was positive for IgG DGP-AGA (detected in 88.7% of patients with celiac disease). IgA tTGA and IgA EmA were negative in all GS patients, whereas their positivity in celiac patients was 98.7% and 95%, respectively. Patients with GS displayed a variegated clinical picture with intestinal and extraintestinal symptoms (abdominal pain, bloating, diarrhea, constipation, foggy mind, tiredness, eczema/skin rash, headache, joint/muscle pain, numbness of legs/arms, depression, and anemia) together with normal or mildly abnormal small intestinal mucosa. The serological pattern of GS is characterized by IgG AGA positivity in more than half of cases associated to IgA AGA in a few patients, but without EmA, tTGA, and DGP-AGA, which are the specific markers of celiac disease.