Pathology of celiac disease: a brief review

Celiac disease is a gluten or prolamine-induced immunological disorder primarily affecting the intestines. Celiac disease is often missed since not only are clinical findings 'not typical' but also because many cases are asymptomatic. The diagnosis is based on a constellation of clinical, serological and histological findings in a duodenal biopsy, in addition to HLA genotype.and response to a gluten-free diet.Although some guidelines suggest that histology may not mandatory in every case, by and large changes in mucosal biopsies of the duodenum still remain an important diagnostic tool. The evaluation of a duodenal biopsy requires a properly oriented and satisfactory hematoxylin & eosin stained paraffin section. A poorly oriented and technically suboptimal biopsy is not uncommonly the reason for erroneous interpretation. An increase in intraepithelial lymphocytes [IELs] and an alteration of the crypt: villus ratio forms the basis of diagnosis. These are semiquantitavely classified. Despite varying opinions related to the cut-off values of IELs and findings that recommend appropriate site, number and size of the biopsy specimens, the sensitivity of biopsies vary from 90%-100%. Interpretation of histological findings require correlation with other evidences since the changes in duodenal biopsy may be similar to those seen in a host of other diseases including tropical sprue. It must also be mentioned that in the Indian subcontinent is that reference values for normal duodenal biopsies are lacking, making interpretation difficult especially when changes are mild. Histological changes in the duodenal mucosa often take months to normalize after clinical remission. This is a review of various aspects related to the histological changes in duodenal mucosal biopsies that aid in the diagnosis and follow-up of cases of celiac disease.