Crohn Disease

Introduction

• Description: An idiopathic inflammatory bowel disease characterized by transmural involvement resulting in severe gastrointestinal symptoms and significant morbidity.

• Prevalence: 2–10/10,000 people, slightly more women than men.

• Predominant Age: 15–30 years.

• Genetics: First-degree relative for 20% of patients; more common in Whites and Jewish population. Significant associations with NOD2/CARD15 variants.

Etiology And Pathogenesis

• Causes: The inflammatory process in Crohn disease is transmural and involves both the large and small bowel in 80% of patients.

• Risk Factors: Cigarette smoking, sleep deprivation. There is some evidence for reduced levels of vitamin D as a risk factor.

Signs And Symptoms

• Abdominal pain (80%–85%; often lasting for days or weeks; the pain described is frequently located in the mid-abdomen or right lower quadrant, although generalized pain is often present)

• Diarrhea (20%; voluminous, watery, with occasional blood)

• Fatigue

• Weight loss

• Fever

• Dyspareunia

• Vulvar or perineal fissures or fistulae, or occasionally vulvar granulomas (30% of patients)

• Arthritis, sclerosing cholangitis (5%–10%)

Diagnostic Approach