What are the symptoms and treatment options for diverticulitis?

Symptoms of Diverticulitis

Left lower quadrant abdominal pain is the hallmark symptom of diverticulitis, typically accompanied by fever, altered bowel habits, nausea, and elevated inflammatory markers. 1

Primary Clinical Presentation

The classic symptom triad includes:

• Left lower quadrant pain is the most common presenting symptom, though this complete triad appears in only approximately 25% of patients 2, 1
• Fever occurs frequently as part of the inflammatory response 1, 3
• Leukocytosis (elevated white blood cell count) is commonly present 2, 1

Additional Common Symptoms

Beyond the classic triad, patients frequently experience:

• Change in bowel habits - either constipation or diarrhea 1, 4
• Nausea and vomiting 3, 4
• Anorexia (loss of appetite) 4
• Dysuria (painful urination) may occur if inflammation affects the bladder 4
• Abdominal distention can develop 4

Physical Examination Findings

• Abdominal tenderness localized to the left lower quadrant is the most common physical finding on examination 1, 5
• Peritoneal signs may be present in complicated cases requiring urgent surgical evaluation 3

Laboratory Abnormalities

• Elevated C-reactive protein is frequently observed alongside leukocytosis 1, 4
• These inflammatory markers help support the diagnosis but are not specific 4

Important Clinical Caveat

Misdiagnosis based on clinical assessment alone occurs in 34% to 68% of cases, which is why imaging (particularly CT scan) has become increasingly important for confirming the diagnosis rather than relying solely on symptoms 2. The absence of the classic triad does not exclude diverticulitis, and atypical presentations are common, particularly in elderly or immunocompromised patients 2, 3.

---

Treatment Options for Diverticulitis

For uncomplicated diverticulitis in stable patients, conservative management without antibiotics is now recommended, using only acetaminophen for pain control and dietary modification. 1, 3

Treatment Algorithm Based on Disease Severity

Uncomplicated Diverticulitis (85% of cases)

First-line approach - observation without antibiotics:

• Pain management with acetaminophen (avoid NSAIDs as they increase diverticulitis risk) 1, 3
• Clear liquid diet during acute phase, advancing as tolerated 6, 3
• Outpatient management is appropriate for most patients 1, 3

Selective antibiotic use is reserved for specific high-risk patients:

• Age >80 years 1, 3
• Immunocompromised status (chemotherapy, high-dose steroids, organ transplant recipients) 1, 3
• Pregnancy 3
• Significant comorbidities (cirrhosis, chronic kidney disease, heart failure, poorly controlled diabetes) 1, 3
• Persistent fever or chills 3
• Increasing leukocytosis 3
• Frailty 1

When antibiotics are indicated for uncomplicated disease:

• Oral amoxicillin-clavulanate 875/125 mg twice daily for 7 days is first-line 6
• Alternative: Ciprofloxacin 500 mg twice daily plus metronidazole 500 mg three times daily for 7 days (for penicillin allergy) 6
• Alternative: Cefalexin with metronidazole 3

Complicated Diverticulitis (12-15% of cases)

Complications include abscess, peritonitis, obstruction, stricture, or fistula 1.

Intravenous antibiotic therapy is mandatory:

• Ceftriaxone plus metronidazole OR piperacillin-tazobactam 1, 3
• Alternative: Cefuroxime plus metronidazole OR ampicillin/sulbactam 3

Additional interventions based on specific complications:

• Percutaneous drainage for abscesses ≥3-4 cm 1, 3
• Surgical intervention is necessary for:
  • Failed percutaneous drainage 1
  • Generalized peritonitis (requires emergent laparotomy) 1, 3
  • Fistula formation 1
  • Obstruction or stricture 1
  • Free perforation 2

Laparoscopic surgery is preferred over open colectomy when surgery is required, resulting in shorter hospital stays, fewer complications, and lower mortality 4. Postoperative mortality is 0.5% for elective resection versus 10.6% for emergent resection 3.

Hospitalization Criteria

Admit patients with:

• Inability to tolerate oral intake 6, 3
• Signs of peritonitis 2, 4
• Severe pain 6
• Sepsis or hemodynamic instability 6, 3
• Suspected complicated diverticulitis 2, 4

Follow-Up Care

• Colonoscopy 6-8 weeks after symptom resolution is recommended for complicated diverticulitis, first episode of uncomplicated diverticulitis, or if high-quality colonoscopy was not performed within the past year 1, 6
• Re-evaluation within 7 days is mandatory for outpatient-managed cases to assess for complications 6

Long-Term Prevention

• High-fiber diet or fiber supplementation 1, 4
• Regular exercise 1, 4
• Smoking cessation 1, 4
• Weight loss for BMI ≥30 kg/m² 1, 4
• Avoid regular NSAID use when possible 6, 4
• Low to modest doses of tricyclic antidepressants may help with persistent visceral hypersensitivity (45% report periodic pain at 1 year) 1