Complicated small-bowel diverticulosis: A case report and review of the literature
Executive Summary
Jejunoileal diverticulosis is a rare clinical entity characterized by the presence of acquired "false" diverticula—herniations of the mucosa and submucosa through the muscular layer of the bowel wall. Despite its first description over 200 years ago, the condition remains a significant diagnostic challenge due to its often asymptomatic nature and non-specific clinical presentation, which frequently mimics other abdominal conditions such as appendicitis or irritable bowel syndrome (IBS).
While many cases remain silent, complications occur in 10% to 30% of patients and carry a high mortality rate—reaching as high as 24% in instances of diverticulitis. Standard imaging, including Computed Tomography (CT), often lacks the diagnostic features necessary for a definitive identification of the disorder. Consequently, diagnostic laparoscopy has emerged as the preferred method for reaching an absolute diagnosis in acute cases. The definitive treatment for symptomatic complications is the surgical resection of the affected bowel segment followed by primary anastomosis.
Epidemiology and Anatomical Distribution
The prevalence of small-bowel diverticula is low, with autopsy data indicating a range between 0.06% and 1.3%. The condition typically manifests later in life, with incidence peaking during the sixth and seventh decades.
Distribution of Diverticula
Small-bowel diverticula are most frequently found in the proximal portion of the small intestine and decrease in frequency toward the distal end.
Furthermore, the condition often coexists with diverticula in other regions of the gastrointestinal tract, suggesting a potentially common etiology:
Colonic Diverticula: Coexistent in 20% to 70% of cases.
Duodenal Diverticula: Coexistent in 10% to 40% of cases.
Esophageal/Gastric Diverticula: Coexistent in approximately 2% of cases.
Pathophysiology and Etiology
Jejunoileal diverticula are generally acquired "pulsion" lesions. They occur on the mesenteric border of the bowel where paired blood vessels penetrate the muscularis, creating a point of weakness.
Underlying Muscle and Nerve Abnormalities
Current hypotheses suggest that distorted smooth muscle contractions generate increased intraluminal pressure, leading to herniation. Microscopic evaluations have identified three primary types of abnormalities in affected specimens:
Systemic Sclerosis-like Changes: Fibrosis combined with a decreased number of normal muscle cells.
Visceral Myopathy: Fibrosis and degenerated smooth muscle cells.
Visceral Neuropathy: Neuronal and axonal degeneration.
Clinical Presentation and Diagnostic Challenges
The clinical recognition of jejunoileal diverticulosis is difficult because the symptoms are "vague and diverse." Up to 90% of symptomatic patients present with complaints similar to IBS, including intermittent abdominal pain, constipation, and diarrhea.
Diagnostic Limitations
Radiography/CT: Imaging often shows atypical appearances without key diagnostic features. CT may identify large localized abscesses but often fails to identify diffuse inflammatory changes.
Endoscopy: While capsule endoscopy and double-balloon enteroscopy are useful for general small-bowel disorders, their utility in emergency situations is limited by factors such as mechanical obstruction, scarring, or stenosis.
Diagnostic Laparoscopy: In the absence of contraindications, this is the most effective tool for thorough examination. It allows for an accurate diagnosis while avoiding the risks associated with unnecessary laparotomy.
Complications and Surgical Management
Complications requiring surgical intervention are reported in 8% to 30% of patients. Compared to duodenal diverticula, jejunoileal diverticula are four times more likely to develop complications and 18 times more likely to perforate.
Acute Complications
Diverticulitis: Occurs in 2% to 6% of cases; mortality is approximately 24%.
Perforation and Abscess: Often leads to localized or diffuse peritonitis.
Intestinal Obstruction: Caused by pressure from inflammatory masses, adhesions, or stenosis.
Hemorrhage: Acute bleeding from the diverticular site.
Management Protocols
Conservative Treatment: Initial management for chronic pain, bacterial overgrowth, or malabsorption syndromes.
Surgical Resection: The preferred treatment for acute complications. The procedure involves resecting the entire involved segment with primary anastomosis.
Comparative Risk: Procedures such as simple excision or closure are discouraged, as they are associated with a three-fold increase in mortality compared to formal resection.
Case Analysis: Complicated Diverticulitis in an 85-Year-Old Patient
A clinical case involving an 85-year-old male illustrates the diagnostic and therapeutic complexities of the disease.
Clinical Findings
The patient presented with diffuse, severe abdominal pain and a history of heart disease, COPD, and atrial fibrillation. Laboratory tests showed elevated white blood cell counts (12,900/mm³) and C-reactive protein (32.48 mg/L). An initial CT scan was inconclusive, showing no abnormalities other than prostate hypertrophy and no visible pneumoperitoneum.
Surgical Intervention and Outcome
Diagnosis: Laparoscopic evaluation revealed jejunal diverticulosis complicated by diverticulitis and mesenteric abscesses, coexisting with sigmoid diverticulitis.
Procedure: The surgeons converted to laparotomy, identifying a 100-cm segment of the jejunum containing multiple diverticula and signs of perforation. Treatment included:
Resection of the 100-cm jejunal segment with primary anastomosis.
Sigmoid colectomy with temporary end colostomy (Hartmann’s procedure).
Pathology: Confirmed perforated diverticulitis and purulent peridiverticulitis.
Recovery: Despite postoperative complications (pneumonia and wound infection), the patient recovered following medical management and was discharged.
Conclusion
Jejunoileal diverticulosis remains a formidable challenge in clinical practice. It should be highly suspected in older patients presenting with unexplained abdominal symptoms. Because of the risk of life-threatening complications, an aggressive surgical approach—specifically resection with primary anastomosis—is justified when conservative measures fail or when acute complications such as perforation or obstruction are identified.
