What are the causes of and treatments for pain that mimics diverticulitis?

Causes of and Pain That Mimics Diverticulitis

Diverticulitis can be mimicked by several other conditions that present with similar symptoms, requiring careful diagnostic evaluation to differentiate between them and ensure appropriate treatment.

Common Conditions That Mimic Diverticulitis

Gastrointestinal Causes

• Colorectal cancer: Perforated colon cancer can present with similar clinical and radiographic findings as diverticulitis 1. Key differentiating features include:

  • Presence of pericolonic lymphadenopathy >1 cm in short axis
  • Absence of inflammatory changes in the root of sigmoid mesentery
  • Higher likelihood when abscess, local perforation, or fistula is identified 1

• Irritable Bowel Syndrome (IBS): May cause recurrent abdominal pain but typically lacks fever, leukocytosis, or inflammatory markers

• Inflammatory Bowel Disease: Can present with similar pain patterns but often has more chronic symptoms and different imaging findings

• Segmental Colitis Associated with Diverticular Disease (SCAD): A rare diagnosis characterized by diverticular colitis that spares the rectum, likely on the spectrum of inflammatory bowel diseases 1

Gynecologic Causes (in women)

• Pelvic Inflammatory Disease
• Ovarian cysts or torsion
• Ectopic pregnancy
• Endometriosis

Urologic Causes

• Urinary tract infection
• Kidney stones
• Pyelonephritis

Other Causes

• Appendicitis: Particularly when the appendix is in an atypical position
• Small bowel obstruction
• Mesenteric ischemia
• Abdominal wall hernias

Diagnostic Approach

Clinical Presentation

• Typical diverticulitis presents with:
  • Left lower quadrant pain
  • Fever
  • Elevated white blood cell count 1
  • Tenderness localized to the left lower quadrant 1
  • Elevated C-reactive protein 1

Imaging

• CT scan with IV contrast: Gold standard for diagnosis with 98-99% sensitivity and specificity 1, 2

  • Findings suggestive of diverticulitis include:
    • Pericolonic fat stranding
    • Bowel wall thickening
    • Presence of diverticula
    • Inflamed diverticulum
    • Arrowhead sign (contrast material at the orifice of inflamed diverticulum) 1

• Ultrasound: Alternative when radiation exposure is a concern

  • Shows thickened loop of bowel with target-like appearance
  • Sensitivity and specificity comparable to CT but more operator-dependent 1

• MRI: Can be used when CT is contraindicated

  • Superior resolution of soft tissues
  • No ionizing radiation
  • Limited by longer scan times and higher cost 1

Treatment Approach for Diverticulitis

Uncomplicated Diverticulitis

• Conservative management:
  • Observation with pain management (typically acetaminophen) 2
  • Dietary modification with clear liquid diet 2
  • Antibiotics should be reserved for patients with:
    • Systemic symptoms (persistent fever/chills)
    • Increasing leukocytosis
    • Age >80 years
    • Pregnancy
    • Immunocompromised status
    • Chronic medical conditions (cirrhosis, CKD, heart failure, poorly controlled diabetes) 2

Complicated Diverticulitis

• Inpatient management:
  • IV fluid resuscitation
  • IV antibiotics (ceftriaxone plus metronidazole or piperacillin-tazobactam) 2
  • Surgical consultation
  • Percutaneous drainage for abscesses ≥3-4 cm 3, 4

Important Pitfalls to Avoid

1. Misdiagnosing colorectal cancer as diverticulitis: Consider colonoscopy 6-8 weeks after resolution of symptoms, especially after complicated diverticulitis 1, 3

2. Overuse of antibiotics: Recent evidence indicates antibiotics may not be necessary for mild to moderate uncomplicated diverticulitis 4, 5

3. Delayed diagnosis of alternative conditions: Maintain a broad differential diagnosis, especially when symptoms don't improve with standard treatment

4. Inappropriate dietary restrictions: The myth of avoiding nuts, corn, popcorn, and seeds to prevent diverticulitis has been debunked 6

5. Missing complications: Always assess for signs of perforation, abscess formation, fistula development, or obstruction in patients with severe symptoms or those who fail to improve 1

By maintaining awareness of these mimicking conditions and following a structured diagnostic approach, clinicians can more accurately diagnose diverticulitis and its mimics, leading to appropriate treatment and improved patient outcomes.