Crohn’s Disease

Description

Crohn’s disease is a chronic inflammatory bowel disease that can affect any part of the gastrointestinal tract, although it most commonly involves the terminal ileum and the cecum. It is characterized by discontinuous (“skip”) lesions, with inflamed bowel segments separated by normal tissue. The inflammation is transmural, often involving the entire thickness of the intestinal wall.

The prevalence of Crohn’s disease is approximately 20–50 cases per 100,000 people. The prevalence in Lithuania is lower, although the incidence has been increasing annually. The disease most commonly affects young adults between 18 and 35 years of age.

Cause

The exact cause of Crohn’s disease remains unknown. It is believed to result from the interaction of genetic susceptibility, immune dysregulation, and environmental factors. Genetic factors contribute to disease susceptibility, while an abnormal immune response causes inflammation directed against the intestinal mucosa. Environmental factors, such as stress and dietary habits, do not directly cause Crohn’s disease but may trigger disease onset or exacerbations in genetically susceptible individuals.

Risk Factors

Risk factors for Crohn’s disease include:

• Young age (most commonly around 30 years).
• Family history of Crohn’s disease.
• Residence in highly industrialized urban areas.

Symptoms

Crohn’s disease may affect any part of the gastrointestinal tract; therefore, clinical manifestations vary according to the site of involvement. Common symptoms include:

• Abdominal pain (persistent pain in the right lower quadrant; postprandial cramping relieved by passing flatus; colicky pain associated with nausea and vomiting that may improve after defecation).
• Diarrhea, which may contain mucus or blood.
• Loss of appetite and weight loss.
• Perianal disease, including fissures and ulcers.

Diagnosis

The diagnosis of Crohn’s disease can be challenging because of its variable clinical presentation. In many cases, diagnosis is established several months after the onset of symptoms. Blood tests may demonstrate anemia, leukocytosis, and elevated C-reactive protein (CRP) levels. Ileocolonoscopy with biopsy is the cornerstone of diagnosis. Upper gastrointestinal endoscopy with examination of the terminal ileum may also be performed when indicated. Tissue samples obtained during endoscopy are examined histopathologically to confirm the diagnosis.

Treatment

Treatment includes anti-inflammatory medications such as mesalazine and sulfasalazine. Antibiotics may be used in selected cases. If these treatments are ineffective, corticosteroids, including prednisolone or budesonide, may be prescribed. Immunomodulatory agents such as azathioprine and mercaptopurine are also used. In severe or refractory disease, biologic therapies, including infliximab and adalimumab, may be required.

A well-balanced diet with adequate caloric intake is an important part of disease management.

Source | Author Doctor Nikas Samuolis, reviewed by Prof. Virginijus Šapoka | Vilnius University | Faculty of Medicine | Head of the Department of Internal Medicine, Family Medicine, and Oncology