What is important to know about managing segmental colitis?

Managing Segmental Colitis: Key Considerations and Approach

Segmental colitis associated with diverticulosis (SCAD) should be considered in elderly patients with isolated sigmoid colon inflammation, as it is an underrecognized but not rare condition affecting up to 3.8% of patients with diverticulosis. 1

Diagnostic Approach

Clinical Presentation

• Most common presenting symptoms include:
  • Abdominal pain (33.3%)
  • Hematochezia/rectal bleeding (22.7%) 1
  • Diarrhea
  • Urgency

Diagnostic Workup

1. Laboratory investigations:

   • Complete blood count
   • C-reactive protein
   • Serum albumin
   • Stool samples to exclude infectious agents 2

2. Endoscopic evaluation:

   • Colonoscopy with segmental biopsies is essential
   • Multiple biopsies from different sites increase diagnostic accuracy from 66% to 92% 2
   • Isolated sigmoid inflammation is the most common endoscopic finding (86.7%) 1
   • Biopsies should be taken from both inflamed and normal-appearing mucosa 2, 3

3. Histological assessment:

   • Serial sectioning of biopsy specimens is superior to step sectioning for detecting mild or focal lesions 2
   • Routine staining with hematoxylin and eosin is appropriate 2

4. Cross-sectional imaging:

   • CT scan can help differentiate SCAD from other conditions
   • Penetrating disease is seen in 13.7% of SCAD cases 1
   • Radiologists correctly diagnose SCAD in only 43.8% of cases, highlighting the importance of endoscopic confirmation 1

Differential Diagnosis

Important conditions to differentiate from segmental colitis:

1. Inflammatory Bowel Disease (IBD):

   • SCAD shares pathogenic and therapeutic aspects with IBD 4
   • Unlike IBD, SCAD typically has rectal sparing 5

2. Diverticulitis:

   • 49.3% of SCAD patients have a prior episode of diverticulitis 1
   • Penetrating disease is not a specific radiologic feature for either SCAD or diverticulitis 1

3. Infectious colitis:

   • Rule out Clostridioides difficile infection
   • Consider CMV colitis in immunocompromised patients 2

4. Ischemic colitis:

   • Some SCAD cases may have histology suggestive of ischemic colitis 5

5. Segmental colitis from other causes:

   • Medication-induced colitis
   • Radiation colitis 2

Management Approach

First-line Treatment

• Most common effective treatments include:
  • Antibiotics (42.7% of cases) 1
  • Mesalamine (36.0% of cases) 1

Treatment Monitoring

• Regular assessment of:
  • Stool frequency and consistency
  • Clinical parameters
  • Inflammatory markers

Refractory Disease

• For patients not responding to first-line therapy:
  • Consider systemic corticosteroids 2
  • Evaluate for complications such as toxic megacolon or perforation
  • Surgical consultation may be needed

Surgical Intervention

• Required in approximately 26.7% of SCAD cases 1
• Indications include:
  • Refractory disease not responding to medical therapy
  • Development of complications (perforation, stricture, obstruction)
  • Rare complications like hydroureteronephrosis 6

Prognosis and Follow-up

• Most cases respond to medical therapy with antibiotics and/or mesalamine 5
• No evolution to inflammatory bowel disease has been observed in follow-up studies 5
• Regular follow-up colonoscopies may be needed to monitor disease activity and rule out malignancy

Clinical Pitfalls and Caveats

1. Diagnostic challenges:

   • SCAD can be misdiagnosed as IBD, particularly ulcerative colitis 5
   • Segmental biopsies are essential for accurate diagnosis 3

2. Treatment considerations:

   • Avoid overtreatment with immunosuppressants if antibiotics and mesalamine are effective
   • Consider surgical consultation early for refractory cases

3. Monitoring:

   • Regular follow-up is essential to ensure resolution and detect complications
   • Patients with a history of diverticulitis should be monitored for development of SCAD

4. Elderly patients:

   • Consider SCAD in the differential diagnosis for elderly patients with isolated sigmoid inflammation 2
   • Assess candidacy for immunosuppression based on functional status and comorbidities 2

By following this structured approach to diagnosis and management, clinicians can effectively identify and treat segmental colitis, improving patient outcomes and quality of life.