Schaumann bodies deposited along myenteric plexus of the muscularis propria is a unique histopathological feature of Crohn’s disease

Schaumann bodies were first identified in sarcoidosis by Dr Schaumann in 1941. They were also detected in 10% of Crohn's disease (CD) cases in a study involving patients with surgically resected CD. However, the characteristics and significance of Schaumann bodies in CD have yet to be fully elucidated. This study aimed to determine the pathological features and diagnostic significance of Schaumann bodies in various bowel diseases.Overall, 278 bowel specimens were collected from patients with CD, intestinal tuberculosis, ulcerative colitis, intestinal schistosomiasis, diverticulosis and idiopathic mesenteric vasculopathy. The frequency, pathology and clinical features of patients with Schaumann bodies were studied.Schaumann bodies were present exclusively in CD (27.0%, 38 of 141) and were not detected in other intestinal diseases within the series. In CD, Schaumann bodies were deposited along the myenteric plexus of the muscularis propria (84.2%, 32 of 38). These bodies were small (diameter: 60.3±32.7 µm) and exhibited a low density in the intestinal wall (1.1±0.4 per low-power field). The majority were located within the cytoplasm of multinucleated giant cells (84.2%, 32 of 38) and were not found within or adjacent to granulomas. Notably, the number of female patients with CD and Schaumann bodies was higher than that of males.Schaumann bodies are common in resected CD specimens, and their characteristic deposition pattern may serve as a diagnostic indication for CD.