Crohn Disease

Overview


Plain-Language Overview

Crohn Disease is a chronic condition that affects the digestive system, primarily the intestines. It causes inflammation that can lead to symptoms like abdominal pain, diarrhea, and sometimes weight loss. The inflammation can occur anywhere from the mouth to the anus but most commonly affects the end of the small intestine and the beginning of the colon. This disease can cause the walls of the intestines to become thickened and develop ulcers, which may lead to complications such as blockages or fistulas. People with Crohn Disease often experience periods of flare-ups and remission, impacting their overall health and quality of life.

Clinical Definition

Crohn Disease is a chronic, relapsing inflammatory bowel disease characterized by transmural granulomatous inflammation that can affect any part of the gastrointestinal tract from mouth to anus. The exact cause is unknown but involves a combination of genetic susceptibility (including mutations in NOD2), immune dysregulation, and environmental factors. The inflammation is patchy and segmental, often leading to skip lesions and complications such as strictures, fistulas, and abscesses. It is distinguished from ulcerative colitis by its transmural involvement and potential to affect the entire GI tract. Clinically, it presents with abdominal pain, chronic diarrhea, weight loss, and extraintestinal manifestations such as arthritis and skin lesions. The disease course is typically chronic with periods of exacerbation and remission.

Inciting Event

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Clinical Presentation


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Pathophysiology


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