Detection of pyloric metaplasia may improve the biopsy diagnosis of Crohn's ileitis.

BACKGROUND: Pyloric metaplasia (PYME) is seen frequently in ileal resections from patients with Crohn's disease (CD). It represents a nonspecific reparative reaction in intestinal ulcers. The presence of PYME in terminal ileum biopsies (TIbxs) of CD has not received much attention and has been considered a rare finding. STUDY: We reviewed 45 TIbxs from 45 adult patients with indisputable clinicopathologic diagnosis of CD. Endoscopic biopsies were obtained with an Olympus CIF 140 videoscope. The samples were fixed in 10% buffered formalin and were processed routinely. RESULTS: Pyloric metaplasia was identified in 10 TIbxs from 10 patients. Most of the metaplastic glands formed small aggregates in the mucosal base, and they were frequently noted below regenerating crypts and in the vicinity of granulation tissue and ulceration. CONCLUSIONS: In our material, 22.2% of the TIbxs revealed PYME. The single previous study with similar data showed an incidence of 2.27%. The difference could reflect the stage of the disease or the thoroughness of the endoscopic and pathologic examinations. Pyloric metaplasia, despite its lack of specificity, remains a sensitive indicator of persistent ulceration with inflammation. Because PYME is not as rare as previously thought, it should be carefully looked for in TIbxs to support the diagnosis of CD in the appropriate clinical setting.