Some patients with Celiac Disease may continue to experience small intestinal damage (villous atrophy), despite following a strict gluten-free lifestyle. These patients are often given a diagnosis of Nonresponsive Celiac Disease (NRCD) defined in the below mentioned Study Abstract as “persistent villous atrophy and CD-associated symptoms despite a year or more of strict GFD”, and after ruling out that gluten is continuing to be ingested or other disorders such as IBS, Lactose Intolerance, Microscopic Colitis and Small Intestinal Bacterial Overgrowth (SIBO), are to blame.
Current assessments to determine if the small intestines are healing, involve invasive and costly intestinal biopsies. As noted in a recent Medscape.com article, researchers from the US and Finland set out to identify certain antibody biomarkers for patients with Celiac Disease who are not healing (despite being 100% gluten-free). “Serological measures of the response of CD patients to a GFD that identify patients with NRCD would have substantial clinical value”. Discovering a biomarker will help identify nonresponsive patients sooner, rather than later, so assessments can be made for “more aggressive therapy” in order to avoid other health complications down the road such as ulcerative jejunitis, enteropathy-associated T-cell lymphoma and non-Hodgkin’s lymphomas, epithelial neoplasms, oesophageal and pharyngeal squamous cell carcinomas, and concomitant autoimmune diseases, as mentioned in the abstract.
Bacterial display peptide libraries were screened by flow cytometry to identify epitopes specifically recognised by antibodies from patients with NRCD, but not by antibodies from responsive CD patients. Deamidated gliadin was confirmed to be the antigen mimicked by library peptides using ELISA with sera from NRCD ( n = 15) and responsive CD ( n = 45) patients on a strict GFD for at least 1 year.
The dominant consensus epitope sequence identified by unbiased library screening QPxx(A/P)FP(E/D) was highly similar to reported deamidated gliadin peptide (dGP) B-cell epitopes. Measurement of anti-dGP IgG titre by ELISA discriminated between NRCD and responsive CD patients with 87% sensitivity and 89% specificity. Importantly, dGP antibody titre correlated with the severity of mucosal damage indicating that IgG dGP titres may be useful to monitor small intestinal mucosal recovery on a GFD.
The finding of increased levels of anti-dGP IgG antibodies in CD patients on strict GFDs effectively identifies patients with NRCD. Finally, anti-dGP IgG assays may be useful to monitor mucosal damage and histological improvement in CD patients on a strict GFD.
The results of the study support the use of dGP serology in the clinical follow-up of individuals with CD, thus avoiding a more invasive biopsy to determine if a patient has Nonresponsive Celiac Disease.
For complete study details please view Medscape.com article HERE.