# Diverticular Disease > NEET-PG Surgery notes on diverticular disease: Hinchey staging, CT diagnosis, antibiotic and drainage pathways, Hartmann's procedure and diverticular bleeding. - Canonical URL: https://prepelephant.com/topics/neet-pg/surgery/diverticular-disease - Exam / course: NEET-PG · Subject: Surgery - Publisher: PrepElephant (https://prepelephant.com) — Prepared and reviewed by the PrepElephant Academic Review Team - First published: 2026-10-02 - Last updated: 2026-10-02 - How to cite: "Diverticular Disease", PrepElephant, https://prepelephant.com/topics/neet-pg/surgery/diverticular-disease ## Direct answer Diverticular disease begins as pulsion herniation of colonic mucosa through the circular muscle where the vasa recta penetrate the wall, which is why diverticula cluster in the sigmoid colon, the narrowest and highest-pressure segment. Uncomplicated diverticulitis — left iliac fossa pain, fever, tenderness, raised inflammatory markers — is treated with antibiotics and bowel rest; complicated disease follows the Hinchey stages from pericolic abscess through distant abscess to purulent and faecal peritonitis. Percutaneous drainage bridges the abscess stages, while Hinchey III and IV need laparotomy with Hartmann's procedure or resection with primary anastomosis and a defunctioning stoma. Diverticular bleeding is a separate entity: painless haematochezia that stops spontaneously in most patients. ## What you must remember - **Hinchey staging:** Stage I pericolic or mesenteric abscess; Stage II pelvic or distant abscess; Stage III generalized purulent peritonitis; Stage IV faecal peritonitis — the stage dictates the operation. - **Investigation of choice:** contrast-enhanced CT showing segmental wall thickening, fat stranding and complications; colonoscopy is contraindicated during the acute attack and is performed about six weeks later to exclude cancer. - **Uncomplicated attack:** bowel rest, analgesia and antibiotics covering gram-negatives and anaerobes; selected mild cases may even resolve without antibiotics per current guidance. - **Abscess rule of thumb:** collections under about 4 cm may resolve with antibiotics alone; larger ones need image-guided percutaneous drainage before any decision to resect. - **Hinchey III:** resection with primary anastomosis and defunctioning ileostomy in a stable patient, or Hartmann's procedure (sigmoid resection, end colostomy, rectal stump) in the unwell or faecally soiled patient. - **Hinchey IV:** resuscitation, antibiotics and source control — traditionally Hartmann's; laparoscopic lavage alone has a selected, contested role. - **Diverticular bleeding:** typically painless, from a single eroded artery at the neck of a diverticulum, self-limiting in the great majority; localise with CT angiography and treat refractory bleeding with embolisation. - **Asian pattern:** right-sided colonic diverticula are distinctly commoner in East Asian populations, so right iliac fossa diverticulitis mimics appendicitis there. ## Working through a complicated case A 60-year-old man arrives with two days of left iliac fossa pain, vomiting, fever of 38.6 degrees and a rigid abdomen. CT confirms sigmoid diverticulitis with extraluminal gas and free fluid — Hinchey III. He is resuscitated, given broad-spectrum antibiotics, and taken to theatre. Purulent peritonitis with a sealed microperforation is found; the sigmoid is resected. Because he is haemodynamically stable and the soilage is purulent rather than faecal, a primary colorectal anastomosis is created and protected with a loop ileostomy, avoiding the morbidity of a Hartmann's and its notorious non-reversal rate. Had he been shocked with faecal peritonitis, Hartmann's procedure would be safer. Had the CT instead shown a 5 cm walled-off pelvic abscess, the correct first move is percutaneous drainage, converting an emergency into a planned single-stage sigmoid colectomy weeks later. Six weeks after recovery, colonoscopy completes the pathway by excluding a perforated carcinoma masquerading as diverticulitis. ## Where marks are lost Diverticulosis and diverticulitis are not interchangeable — the examiners mark that error early. The second slip is forgetting the timing rule for colonoscopy: scoping an acutely inflamed colon risks perforation, so the study belongs after full recovery. Third, candidates mix the two complications: inflammation causes pain and fever, whereas the eroded vas rectum causes painless bleeding — and massive bleeding needs CT angiography, not urgent colonoscopy in a destabilised patient. Fourth, the smouldering patient with repeated attacks, or one who is immunosuppressed, is a standard indication for elective sigmoid resection after decompression of the acute episode. Finally, remember atypical sites: caecal and right-sided diverticulitis, common in East Asian and reported in Indian series, is a recognised mimic of appendicitis and a favourite one-liner. ## Frequently asked questions ### What does Hinchey Stage III diverticulitis require? Urgent resuscitation, antibiotics and surgery — resection with primary anastomosis protected by a loop ileostomy in a stable patient, or Hartmann's procedure in the unwell patient with purulent peritonitis. ### How is a 6 cm diverticular abscess managed? Image-guided percutaneous drainage plus antibiotics, deferring definitive sigmoid resection to an elective setting once inflammation settles. ### When should colonoscopy be done after acute diverticulitis? Roughly six weeks after resolution, to exclude an underlying neoplasm, since perforated carcinoma can mimic diverticulitis on CT. ### How does diverticular bleeding typically behave? Painless bright rectal bleeding from an eroded artery at a diverticular neck, ceasing spontaneously in most patients; localise and embolise if it persists or destabilises. ### Why is right-sided diverticulitis relevant in Asia? Right-sided diverticula are considerably commoner in East Asian populations, so caecal diverticulitis is a well-recognised mimic of acute appendicitis in that setting.