Refractory celiac sprue (RCS) with an immunophenotypically aberrant clonal intraepithelial lymphocyte (IEL) population is considered a cryptic form of intestinal T cell lymphoma.
In this study, published in the February issue of Gut, researchers investigated the distribution of the abnormal and monoclonal IEL population in the digestive tract of RCS patients.
The team compared the frequency of lymphocytic gastritis (LG) and lymphocytic colitis (LC), together with IEL phenotype and T cell clonality in gastric and colonic samples.
They assessed 15 adults with RCS, 18 with active celiac disease (ACD), and 10 with celiac disease (CD) on a gluten free diet (GFD-CD) using immunohistochemistry and multiplex PCR amplification of the T cell receptor gene (TCR-) rearrangement.
The team also tested the blood samples of 9 RCS patients for clonality.
|Monoclonal TCR-rearrangements were detected in 62% of gastric samples from RCS patients, but in only 8% from CD patients.|
The research team found LG in 64%, 61%, 30% patients with RCS, ACD, and GFD-CD, respectively, while LC was found in 55%, 75%, and 66% patients.
In contrast to CD, all samples from patients with LG and LC showed an aberrant IEL phenotype.
Monoclonal TCR-rearrangements were detected in 62%, 80%, and 44% of gastric, colonic, and blood samples, respectively, from RCS patients.
However, in CD patients such rearrangements were only found in 8% of gastric samples.
Dr Verkarre's team concluded, "The immunophenotypically aberrant monoclonal IEL population present in the small intestine of patients with RCS frequently disseminates to the blood and the entire GI epithelium, suggesting that this is a diffuse GI disease".