الملخص

ABSTRACT Background: Celiac disease is a common, permanent and reversible health problem of small intestine occurring all over the world in genetically predisposed individuals and in combination with other environmental factors. It causes chronic inflammation of small intestine which is of autoimmune origin. The histopathological features of Celiac disease in duodenal biopsy was stated according to the modified Marsh classification. The immunohistochemical application of CD3 marker in duodenal biopsy could facilitate the count and the distribution of intraepithelial lymphocytes along the villi, which is regarded as a key for the correct diagnosis in early stages ( Marsh 1). Objectives: This study was conveyed to correlate the significance of CD3 immunohistochemical expression of intraepithelial lymphocytic population to histopathological changes in Celiac disease, to identify the distribution of CD3 marker along the villi (crescendo or decrescendo) and (diffuse or patchy ) and to delineate the age and sex of Celiac disease in our locality. Materials and methods: The research was both prospective and retrospective case series study, carried out on 100 cases of endoscopically obtained duodenal biopsies. Data obtained from archives of the pathology department, at AL-Jamhory, AL-Khansaa and AL-Salam Teaching Hospitals/ Mosul city, and collected in a period spanning from January 2019 to May 2020. The information included age, sex and duodenal biopsy location. then assessed histologically and immunohistochemically. Results: In a total of 100 duodenal samples, patients age was ranged 1 to 69 years ( mean age of 20.74 years), with a female to male ratio ( 2.2:1). By applying modified Marsh classification: Marsh 0 was detected in 8 % of the cases, Marsh 1 in 30 % , Marsh 2 in 10% , Marsh 3 a in 20%, Marsh 3 b in 17%, Marsh 3 c in 15% and Marsh 4 in 0%. Immunohistochemical expression of CD3 in the sampled cases i.e. CD3 + ≥30 /100 epithelial cells was detected in 79 %. There was a statistically significant difference between CD3+ and modified Marsh classification by Hematoxylin & Eosin (P Value<0.001) for detection of intraepithelial lymphocytosis. Conclusion: There is a significant relationship between the count of CD3+ T-lymphocytes per 100 epithelial cells and the histopathological changes in the duodenal biopsy according to modified Marsh classification. the immunohistochemical expression of CD3 in intraepithelial T-lymphocyte could lead to a definite assessment in 13 % of the sampled cases with Marsh type 1. All the positive cases are of crescendo pattern of distribution of CD3+ T-lymphocytes as the distribution is more important than the actual count and they distributed diffusely except that associated with Helicobacter pylori infection observed with patchy distribution. The IHC expression of CD3+ marker provides a hint about the distribution of CD3+ marker within the lymphocyte whether global surface or clonal surface and intracytoplasmic to diagnose Refractory Celiac disease. Females were more affected than males and there is a significant relationship between the gender and the histopathological changes. It can be diagnosed at any age and there is no significant relationship between the age distribution and the histopathological changes.