Hinchey Classification and Management of Diverticulitis
The Hinchey classification is the most widely used system for categorizing the severity of acute colonic diverticulitis, guiding treatment decisions based on the extent of infection and inflammation beyond the colon. 1
Original Hinchey Classification
The original Hinchey classification categorizes diverticulitis into four stages based on surgical findings:
- Stage 1: Pericolic abscess 1
- Stage 2: Pelvic, intra-abdominal, or retroperitoneal abscess 1
- Stage 3: Generalized purulent peritonitis 1
- Stage 4: Fecal peritonitis 1
Modified Hinchey Classification (Kaiser et al., 2005)
This adaptation incorporates CT findings for more precise diagnosis:
- Stage 0: Mild clinical diverticulitis 1
- Stage 1a: Confined pericolic inflammation 1
- Stage 1b: Confined pericolic abscess 1
- Stage 2: Pelvic or distant intra-abdominal abscess 1
- Stage 3: Generalized purulent peritonitis 1
- Stage 4: Fecal peritonitis at presentation 1
Management Based on Hinchey Classification
Uncomplicated Diverticulitis (Hinchey 0-1a)
- Outpatient treatment for clinically stable, afebrile patients 2
- Selective use of antibiotics - not routinely required for all uncomplicated cases 2
- Follow-up colonoscopy recommended 6 weeks after diagnosis for patients meeting national bowel cancer screening criteria 2
Complicated Diverticulitis with Small Abscess (Hinchey 1b)
- Small abscesses (<4 cm): Non-operative management with bowel rest and antibiotics 1, 2
- Percutaneous drainage may reduce need for emergency surgery 3
Complicated Diverticulitis with Larger Abscess (Hinchey 2)
- Abscesses >4 cm: Percutaneous drainage recommended 1, 2
- Elective surgery following successful conservative management increases likelihood of laparoscopic approach and decreases stoma formation rates 3
Complicated Diverticulitis with Peritonitis (Hinchey 3-4)
- Immediate fluid resuscitation, intravenous antibiotics, and urgent surgery 2
- Surgical options include Hartmann procedure or primary anastomosis (with or without diverting loop ileostomy) 2
WSES Classification (2015)
The World Society of Emergency Surgery proposed a CT-guided classification system that divides diverticulitis into uncomplicated and complicated forms:
Uncomplicated Diverticulitis
- Diverticula, wall thickening, increased density of pericolic fat 1
Complicated Diverticulitis
- Stage 1A: Pericolic air bubbles or small amount of pericolic fluid without abscess 1
- Stage 1B: Abscess ≤4 cm 1
- Stage 2A: Abscess >4 cm 1
- Stage 2B: Distant gas (>5 cm from inflamed bowel segment) 1
- Stage 3: Diffuse fluid without distant free gas 1
- Stage 4: Diffuse fluid with distant free gas 1
Clinical Implications
- The Hinchey classification has significant prognostic value, with higher stages associated with increased morbidity and mortality 4
- CT imaging is essential for accurate classification and management planning 1, 4
- The AAST (American Association for the Surgery of Trauma) grading scale is equivalent to Hinchey in predicting procedural intervention and complications, with the advantage of being applicable preoperatively 5
Common Pitfalls and Caveats
- Relying solely on clinical examination for diagnosis is not recommended due to poor accuracy 1
- Failure to obtain CT imaging may lead to misclassification and inappropriate management 1, 4
- Delaying percutaneous drainage for Hinchey 1b and 2 diverticulitis may increase the need for emergency surgery 3
- Not all patients with uncomplicated diverticulitis require antibiotics; selective use is recommended 2
- Colonoscopy should be performed after resolution of acute episode (approximately 6 weeks) to exclude malignancy, especially in complicated cases 2