Hinchey Classification for Diverticulitis
The Hinchey classification is the most widely used system for categorizing the severity of acute colonic diverticulitis, consisting of four progressive stages that guide treatment decisions based on the extent of infection and inflammation beyond the colon. 1, 2
Original Hinchey Classification
The original classification includes four distinct stages:
- Stage 1: Pericolic abscess confined to the mesentery of the colon 1, 2
- Stage 2: Pelvic, intra-abdominal, or retroperitoneal abscess 1, 2
- Stage 3: Generalized purulent peritonitis 1, 2
- Stage 4: Fecal peritonitis 1, 2
Modified Hinchey Classification
The Modified Hinchey Classification incorporates CT findings for more precise diagnosis:
- Stage 0: Mild clinical diverticulitis 2
- Stage 1a: Confined pericolic inflammation 1
- Stage 1b: Confined pericolic abscess (<4 cm) 1, 3
- Stage 2: Pelvic or distant intra-abdominal abscess (>4 cm) 1, 3
- Stage 3: Generalized purulent peritonitis 1, 2
- Stage 4: Fecal peritonitis 1, 2
Clinical Implications and Management
The classification directly guides treatment approaches:
- CT imaging is essential for accurate classification and management planning 1, 2
- Stage 0-1a: Conservative management with antibiotics 2
- Stage 1b: Non-operative management with bowel rest and antibiotics for small abscesses (<4 cm) 1, 2
- Stage 2: Percutaneous drainage recommended for larger abscesses (>4 cm) 1, 2
- Stage 3-4: Surgical intervention typically required 4
Other Classification Systems
Several other classification systems have been developed to augment the Hinchey classification:
- Modified Neff Classification: Divides Stage 1 into localized pneumoperitoneum (Stage Ia) and local abscess (Stage Ib) 5
- WSES CT-Guided Classification: Divides diverticulitis into uncomplicated and complicated forms with stages ranging from 1A (pericolic air bubbles) to 4 (diffuse fluid with distant free gas) 2
- AAST Classification: Shown to be equivalent to the modified Hinchey classification in predicting procedural intervention and complications, with the advantage of being applicable preoperatively 6
Common Pitfalls and Caveats
- Relying solely on clinical examination for diagnosis is not recommended due to poor accuracy 2
- Failure to obtain CT imaging may lead to misclassification and inappropriate management 2
- Patients with Stage 1b diverticulitis treated conservatively have a significantly higher recurrence rate (41.2%) compared to those with milder disease (13%) 3
- The classification should be used to guide but not dictate management, as patient-specific factors also influence treatment decisions 3
The Hinchey classification remains the gold standard for categorizing diverticulitis severity and guiding appropriate management strategies 1, 2, 7.