The clinicopathological features of extensive small intestinal CD4 T cell infiltration

Methods-Four patients with clinicopathological features suggesting a new di stinct entity defining extensive small intestinal CD4 T cell infiltration w ere observed. Results-All four patients presented with chronic diarrhoea, malabsorption, and weight loss. Biopsy specimens of the small intestine disclosed extensiv e and diffuse infiltration of the lamina propria by pleomorphic small T lym phocytes, which were positive for CD3, CD4, CD5, and the beta chain of cell receptor in all three cases studied and negative for CD103 in all three ca ses studied. It is notable that, in all invaded areas, the infiltrating cel ls showed no histological change throughout the whole evolution. In three p atients, lymphocyte proliferation was monoclonal and there was extraintesti nal involvement. In one patient, lymphoproliferation was oligoclonal and co nfined to the small intestine. In all four patients, there was no evidence of coeliac disease. Although none of the four patients responded to single or multiple drug chemotherapy, median survival was five years, Conclusion-Extensive small intestinal CD4 T cell infiltration is a rare ent ity, distinct from coeliac disease and associated with prolonged survival.