This article was written by pathologists. It aims to help patients understand their pathology report for chronic active ileitis. It includes sections on what chronic active ileitis is, its causes, symptoms, diagnosis, and the microscopic features observed in pathology.
Chronic active ileitis is a term for tissue injury caused by long-term inflammation of the ileum, the final part of the small intestine. The term “chronic” indicates that the inflammation has been present for an extended period, while “active” means that there are ongoing signs of inflammation and tissue injury. This condition can affect the absorption of nutrients and cause various gastrointestinal symptoms.
Chronic active ileitis is a pattern of inflammation and injury that can be caused by a variety of medical conditions, including:
The symptoms of chronic active ileitis can vary but often include:
The diagnosis of chronic active ileitis is made through a combination of clinical evaluation, imaging studies, and a biopsy of the ileum. First, your doctor will assess your symptoms and medical history and perform a physical examination. Then, imaging studies such as CT scans, MRI, and endoscopy are typically performed to visualize inflammation and narrowing of the ileum. During the endoscopy, a biopsy is performed, and the tissue from the ileum is examined under a microscope by a pathologist.
The normal ileum has tall, finger-like projections called villi, with deep crypts (glands) at the base. The lamina propria, the tissue between the villi, contains a mixed population of immune cells, including lymphocytes and plasma cells.
When a pathologist examines a biopsy from the ileum, they look for specific features under the microscope. These include:
In pathology, “chronic” refers to architectural changes in the tissue, such as branching and shortening of the crypts, indicating long-term tissue damage. “Active” refers to ongoing inflammation and tissue injury involving neutrophils, a type of immune cell. Taken together, these terms mean that the condition has been present for a long time and that new tissue injury is still taking place.
Chronic active ileitis can be divided into different activity levels based on the severity of inflammation and tissue injury. These levels include mild, moderate, and severe, each with distinct microscopic features and clinical implications.
Microscopic features: A slight increase in intraepithelial lymphocytes, rare neutrophils in the lamina propria, minimal cryptitis, and mild architectural changes, such as slight crypt branching.
Microscopic features: Moderate increase in intraepithelial lymphocytes and neutrophils, more pronounced cryptitis with c, and noticeable architectural distortion.
Microscopic features: Dense infiltration of neutrophils and lymphocytes, extensive crypt abscesses, significant mucosal ulceration, and marked architectural distortion with fibrosis.