How is scleroderma of the small bowel diagnosed and treated?

Diagnosis of Scleroderma of Small Bowel

The diagnosis of scleroderma involving the small bowel requires a combination of clinical evaluation, imaging studies, and in some cases, histological confirmation through biopsy.

Clinical Presentation

Patients with small bowel involvement in scleroderma typically present with:

• Chronic abdominal pain
• Abdominal distension and bloating
• Early satiety
• Recurrent nausea and vomiting (sometimes feculent and high volume)
• Alternating diarrhea and constipation
• Weight loss and malnutrition if untreated 1
• Symptoms of bacterial overgrowth due to intestinal stasis 2
• Signs of pseudo-obstruction in advanced cases 3

Diagnostic Approach

Laboratory Tests

• Complete blood count
• Electrolytes (particularly potassium and magnesium)
• Renal and liver function tests
• Inflammatory markers (ESR, CRP)
• Nutritional assessment if malnourished:
  • Vitamins A, D, E
  • Iron, ferritin
  • B12, folate
  • Selenium, zinc, copper 1
• Autoantibody testing (especially anti-centromere and anti-Scl-70 antibodies)

Radiological Investigations

1. Plain Abdominal X-ray:

   • May show dilated small bowel loops
   • Can help exclude colonic dilatation
   • Useful for assessing disease extent 1

2. Small Bowel Imaging:

   • Small bowel follow-through or enterography is the current standard for assessing the small intestine 1
   • CT/MR enterography to exclude mechanical obstruction and identify diffusely distended small bowel suggestive of CIPO (chronic intestinal pseudo-obstruction) 1

3. Advanced Imaging:

   • Dynamic MRI of small bowel can be helpful in assessing motility disorders 1

Endoscopic Evaluation

• Upper endoscopy with small bowel biopsies to:
  • Exclude other causes of malabsorption
  • Look for evidence of bacterial overgrowth
  • Obtain tissue samples for histological examination 1

Specialized Tests

• Manometry:

  • Small bowel manometry to detect abnormal motility patterns
  • Can help differentiate between myopathic and neuropathic patterns 1

• Wireless Motility Capsule:

  • Allows continuous assessment of intraluminal pH, temperature, and pressure
  • Measures transit times and pressure profiles
  • Note: Risk of capsule retention in severe cases 1

Histopathological Findings

In scleroderma of the small bowel, characteristic findings include:

• Smooth muscle atrophy and fibrosis of the bowel wall
• Collagen deposition in the lamina propria and submucosa
• Microvasculature damage due to collagen deposits
• Progressive neural damage leading to muscle dysfunction 1, 4

Management Approach

1. Nutritional Support:

   • First-line approach for malnutrition
   • Enteral nutrition when possible
   • Parenteral nutrition for severe cases with malabsorption 5

2. Antimicrobial Therapy:

   • Rotating antibiotics for bacterial overgrowth
   • Typically given in 10-14 day courses with breaks between cycles 2

3. Prokinetic Agents:

   • To improve intestinal motility
   • May have limited efficacy in advanced disease 5

4. Surgical Intervention:

   • Reserved for complications like obstruction or perforation
   • May include resection of severely affected segments in select cases 2, 3
   • Subtotal colectomy may help in cases with colonic pseudo-obstruction 3

Prognosis and Complications

• Small bowel involvement in scleroderma is associated with significant morbidity
• Elderly scleroderma patients with gastrointestinal involvement have the poorest outcomes 1
• Complications include:
  • Malabsorption and malnutrition
  • Bacterial overgrowth
  • Pseudo-obstruction
  • Pneumatosis cystoides intestinalis (air cysts in bowel wall)
  • Pneumoperitoneum in advanced cases 3

Key Considerations

• Early diagnosis is crucial to prevent malnutrition and other complications
• Gastrointestinal tract involvement occurs in approximately 90% of scleroderma patients 6
• Some patients present with gastrointestinal involvement early in the disease without cutaneous manifestations 1
• Long-term parenteral nutrition can offer effective nutritional support in patients with severe small bowel involvement 1