Crohn's disease (known as Regional Enteritis) is a subacute and chronic inflammation of the gastrointestinal (GI) tract wall that extends through all layers. Crohn's disease (CD) is usually first diagnosed in adolescents or young adults but can appear at any time of life.

The clinical course and symptoms vary. In some patients, periods of remission and exacerbation occur but, in others, the disease follows a fulminating course. Although the most common areas in which it is found are the distal ileum and colon, it can occur anywhere along the GI tract. One theory suggests that CD is the result of defects in the immune system in genetically predisposed individuals that allow bacteria to invade the gastric mucosa, resulting in an overactive immune response. Fistulas, fissures, and abscesses form as the inflammation extends into the peritoneum. In advanced cases, the intestinal mucosa has a cobblestone-like appearance. As the disease advances, the bowel wall thickens and becomes fibrotic and the intestinal lumen narrows. Diseased bowel loops sometimes adhere to other loops surrounding the diseased loop.

• Onset of symptoms is usually insidious, with prominent right lower quadrant abdominal pain and diarrhea unrelieved by defecation.
• Abdominal tenderness and spasm are seen.
• Crampy pains occur after meals; the patient tends to limit intake, causing weight loss, malnutrition, and secondary anemia.
• Chronic diarrhea may occur, resulting in a patient who is uncomfortable and is thin and emaciated from inadequate food intake and constant fluid loss. The inflamed intestine may perforate and form intra-abdominal and anal abscesses.
• Fever and leukocytosis occur.
• Abscesses, fistulas, and fissures are common.
• Symptoms extend beyond the GI tract to include joint disorders (e.g., arthritis), skin lesions (e.g., erythema nodosum), ocular disorders (e.g., conjunctivitis), and oral ulcers.

• Barium study of the upper GI tract is the most conclusive diagnostic aid; it shows the classic “string sign” of the terminal ileum (constriction of a segment of intestine) as well as cobblestone-like appearance, fistulas, and fissures. However, this study has fallen out of favor with the introduction of improved CT scan and MRI techniques that can more accurately assess bowel and pelvic disease.
• Endoscopy, colonoscopy, and intestinal biopsies may be used to confirm the diagnosis.
• Video capsule endoscopy can provide extensive evaluation of the small intestine.
• Proctosigmoidoscopic examination, CT scan, and MRI are highly sensitive studies for diagnosis and determining the extent of the disease process.
• Stool examination should be performed for occult blood and steatorrhea.
• Complete blood cell count (decreased Hgb and Hct), erythrocyte sedimentation rate (elevated), albumin, and protein levels (usually decreased owing to malnutrition) should be obtained.

See “Medical Management” under Ulcerative Colitis in Section U for additional information.

See “Nursing Process: The Patient With Inflammatory Bowel Disease” under Ulcerative Colitis in Section U for additional information.

For more information, see Chapter 47 in Hinkle, J. L., & Cheever, K. H. (2018). Brunner and Suddarth's textbook of medical-surgical nursing (14th ed.). Philadelphia, PA: Lippincott Williams & Wilkins.