Jejunal Diverticula – Causes, Symptoms and Treatment

What are Jejunal Diverticula?

Jejunal diverticula are pouch-like outpouchings of the intestinal wall that form in the jejunum – the middle segment of the small intestine. They are classified as pseudodiverticula, meaning that only the mucosal and submucosal layers herniate through weak points in the muscular wall, rather than all layers of the bowel. Jejunal diverticula are less common than colonic diverticula but can carry significant clinical implications when symptomatic or complicated.

Causes and Development

The exact cause of jejunal diverticula is not fully understood, but several contributing factors have been identified:

• Increased intraluminal pressure: Elevated pressure within the small bowel lumen, often due to dysmotility, may force the mucosa through weak points in the muscular wall.
• Motility disorders: Dysfunction of the smooth muscle or the enteric nervous system is considered a key underlying cause.
• Connective tissue weakness: Age-related or constitutional weakness of the connective tissue predisposes individuals to diverticulum formation.
• Mesenteric vessel entry points: Diverticula typically form where mesenteric blood vessels penetrate the bowel wall, as these are natural areas of muscular weakness.

Jejunal diverticula are more prevalent in individuals over 60 years of age and appear to be slightly more common in men than in women.

Symptoms

The majority of jejunal diverticula are asymptomatic and discovered incidentally during imaging studies. When symptoms do occur, they are often nonspecific and may include:

• Chronic or recurrent abdominal pain, often in the left upper abdomen or around the navel
• Bloating and flatulence
• Nausea and vomiting
• Changes in bowel habits (diarrhea or constipation)
• Malabsorption syndrome: Bacterial overgrowth within the diverticula can lead to steatorrhea (fatty stools), vitamin deficiencies (especially vitamin B12), and unintentional weight loss.

Complications

Although uncommon, jejunal diverticula can give rise to serious complications:

• Diverticulitis: Inflammation of one or more diverticula, presenting with abdominal pain, fever, and elevated inflammatory markers.
• Perforation: Rupture of the diverticular wall, potentially leading to life-threatening peritonitis.
• Gastrointestinal bleeding: Erosion of the diverticular mucosa can result in acute or chronic blood loss.
• Intestinal obstruction: Volvulus (bowel twisting) or intussusception may cause bowel obstruction.

Diagnosis

Jejunal diverticula are diagnosed using a combination of imaging and endoscopic techniques:

• CT scan of the abdomen: The preferred method, especially in acute presentations; diverticula appear as air-filled pouches adjacent to the small bowel.
• MR enteroclysis (MRI of the small bowel): Provides detailed visualization of the small intestine without radiation exposure.
• Conventional enteroclysis: Contrast-enhanced fluoroscopic examination of the small bowel for direct visualization of diverticula.
• Capsule endoscopy: A swallowable miniature camera used to assess the small bowel mucosa in detail.
• Hydrogen breath test: Used to detect small intestinal bacterial overgrowth as a cause of malabsorption symptoms.

Treatment

Asymptomatic jejunal diverticula generally require no specific treatment. Management is guided by symptoms and complications:

Conservative Treatment

• Antibiotics: Used to treat bacterial overgrowth or acute diverticulitis (e.g., metronidazole, ciprofloxacin).
• Nutritional support: In cases of malabsorption, dietary adjustments and supplementation of vitamins (e.g., vitamin B12, fat-soluble vitamins) and minerals are recommended.
• Prokinetic agents: Medications that improve bowel motility may help alleviate functional symptoms.

Surgical Treatment

Surgery is indicated for serious complications such as perforation, uncontrolled bleeding, abscess formation, or intestinal obstruction. The affected bowel segment is resected and intestinal continuity is restored via anastomosis.

References

1. Kassahun WT et al. – Small bowel diverticulosis: literature review and clinical experience. Langenbeck's Archives of Surgery, 2013.
2. Macari M, Faust M – Jejunal diverticulitis: CT findings and imaging approach. American Journal of Roentgenology, 2008.
3. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) – Diverticular Disease. U.S. Department of Health and Human Services, 2021.