Crohns

Crohn's disease, often called Crohn's illness or Crohn disease, is a chronic inflammatory bowel disease characterized by transmural inflammation that can affect any part of the gastrointestinal tract, from mouth to anus. It most commonly involves the terminal ileum and colon and often features skip lesions, meaning inflamed segments are interspersed with normal sections. The inflammation can affect deeper layers of the bowel wall and may lead to complications such as strictures or fistulas.

Common symptoms include abdominal pain, persistent diarrhea, weight loss, and fatigue. Blood in the stool may occur, and perianal disease or mouth ulcers can accompany intestinal inflammation. Symptoms can fluctuate, with periods of remission and relapse. Extraintestinal manifestations, such as joint, skin, or eye involvement, may also occur.

The exact cause is unknown, but Crohn's disease is believed to result from the interaction of genetic susceptibility, immune system dysregulation, and environmental triggers. Smoking increases the risk and worsens the disease. It is not caused by infection and is not contagious.

Diagnosis typically involves a combination of clinical evaluation, laboratory tests (for anemia and inflammation), stool tests (such as calprotectin), endoscopic examination with biopsies, and imaging studies (e.g., MR or CT enterography) to assess the extent and location of involvement. Differential diagnosis includes other inflammatory bowel diseases and infections.

Treatment aims to induce and maintain remission and prevent complications. Medications may include corticosteroids for induction of remission, immunomodulators (such as azathioprine or 6-mercaptopurine), and biologic therapies (including anti-TNF agents, anti-integrins, and anti-IL agents). Antibiotics may be used for certain complications. Nutritional support, including specialized diets or enteral nutrition in some cases, is important. Surgery is reserved for complications like strictures or fistulas and does not cure the disease, as recurrence is common. The course varies and requires ongoing medical care.