The Hinchey Classification is a simple staging system useful to determine the severity of acute diverticulitis. With the clinical history, physical examination and a CT scan of the abdomen the situation of the patient can be assessed and the surgeon is able to choose the best course of treatment.
HINCHEY CLASSIFICATION:
Stage I: Phlegmon or localized abscess (pericolic or mesenteric) – Risk of death: 5%
Stage II: Pelvic abscess – Risk of death: 5%
Stage III: Generalized purulent peritonitis – Risk of death: 13%
Stage IV: Generalized fecal peritonitis – Risk of death: 43%
Some authors proposed modifications to the classification. In one modification, the Stage I has been divided into Ia – Phlegmon and Ib – Confined to pericolic or mesenteric abscess. In another modification, the Stage II has been divided into IIa abscesses amenable to percutaneous drainage and IIb complex abscess with or without fistula in later modifications. Despite modifications proposed by multiple authors, the traditional classification is still widely used.

Reproduction from: McDermott FD et al. Minimally invasive and surgical management strategies tailored to the severity of acute diverticulitis. British Journal of Surgery 101(1), January 2014.
REFERENCES & FURTHER READING:
- Sallinen VJ. Staging of acute diverticulitis based on clinical, radiologic,and physiologic parameters. J Trauma Acute Care Surg. Volume 78, Number 3.
- McDermott FD et al. Minimally invasive and surgical management strategies tailored to the severity of acute diverticulitis. British Journal of Surgery 101(1), January 2014.
- Klarenbeek BR. et al. Review of current classifications for diverticular disease and a translation into clinical practice. Int J Colorectal Dis. 2012 Feb; 27(2): 207–214.