Crohn Disease : Microscopic
During the active phase of Crohn disease, numerous neutrophils infiltrate within crypt epithelium (cryptitis) (shown here) or accumulate in the crypt lumen (crypt abscess). There is associated crypt destruction with ulceration. Ulcerated and non-ulcerated histologically-normal areas are sharply demarcated from each other. Image courtesy of Dr. Jean-Christophe Fournet, Paris, France; humpath.com; Used with permission.