DUODENAL MUCOSAL FERRITIN IN RHEUMATOID-ARTHRITIS - IMPLICATIONS FOR ANEMIA OF CHRONIC DISEASE

Anaemia is a common feature of rheumatoid arthritis (RA) and other chr onic diseases. Among the alterations in iron metabolism contributing t o this effect is a decrease in intestinal iron absorption. The mechani sm for this is unknown, but might involve a 'mucosal block' process si milar to that proposed in iron overload, whereby increased expression of an enterocyte storage protein binds absorbed iron and prevents its transfer to the circulation. We examined the effect of disease-modifyi ng therapy on ferritin expression in duodenal mucosa in RA to determin e whether it may play a role in the 'mucosal block' process. Endoscopi c small bowel biopsies were obtained from 11 patients with active RA b oth before, and 6 months after, a course of either gold or methotrexat e (MTX). Mucosal ferritin levels in small bowel and stomach were measu red by radioimmune assay. Duodenal mucosal ferritin decreased signific antly following treatment (p<0.05). There were no changes in gastric m ucosal ferritin. The fall in duodenal mucosal ferritin correlated with indices of disease activity at start of therapy, and the largest decr eases were in those patients showing the best response to treatment in terms of a fall in inflammatory markers. Site-specific changes in muc osal ferritin may underlie the altered iron absorption observed in act ive inflammatory disease by modifying the enterocyte 'mucosal block'.