显微镜下Crohn病的特点是穿壁性炎症。炎细胞（兰色浸润）从黏膜层到黏膜下层、肌层均有浸润，在浆膜表面苍白的肉芽肿中心出现结节性浸润。
Microscopically, Crohn's disease is characterized by transmural inflammation. Here, inflammatory cells (the bluish infiltrates) extend from mucosa through submucosa and muscularis and appear as nodular infiltrates on the serosal surface with pale granulomatous centers.
