Diverticulitis

Hinchey classification (modified)

Staging system for perforated diverticulitis, used to guide management and as the entry criterion for SCANDIV and related lavage-vs-resection trials:

Stage	Description
I	Pericolic/mesenteric abscess or phlegmon
II	Pelvic, distant intra-abdominal, or retroperitoneal abscess
III	Generalized purulent peritonitis
IV	Generalized fecal peritonitis

Stages I-II are generally amenable to non-operative or percutaneous management; III-IV are the surgical-emergency stages and the population studied in the lavage-vs-resection trials below. Note (per SCANDIV): preoperative differentiation between Hinchey III (purulent) and IV (fecal) is not reliably possible — patients selected for lavage should have consent for resection secured as a backup.

Perforated diverticulitis: lavage vs. resection

Central open question in managing Hinchey III perforated diverticulitis. Two strategies:

• Laparoscopic peritoneal lavage — washout + drainage, no resection. Faster, avoids stoma in most cases, but does not remove the diseased segment.
• Primary resection — sigmoid colectomy, with or without primary anastomosis (± diverting loop ileostomy) or as a Hartmann’s procedure (resection + end colostomy). Definitive, but more morbid up front and (per SCANDIV) leaves ~1 in 3 patients with a stoma even at 5 years.

Two major RCTs now in this wiki, both comparing lavage to resection for Hinchey III:

SCANDIV 5-year data (Azhar 2021 - SCANDIV 5-Year Outcomes): no difference between lavage and resection in severe complications (29% vs 25%), mortality (32% vs 25%), or QoL. Lavage: much lower stoma prevalence (8% vs 33%) but higher recurrence (21% vs 4%) and higher unplanned reoperation rate (26% vs 12%); 30% of lavage patients eventually needed sigmoid resection anyway. Most events (both arms) occurred within year 1.

Ladies trial (LOLA group) (Vennix 2015 - Ladies Trial LOLA): more cautionary — stopped early after an interim safety signal (18 vs 2 in-hospital reinterventions, p=.001); 30-day major morbidity significantly higher with lavage (39% vs 19%, p=.043). No difference in the 12-month primary composite or in mortality/QoL. Recurrence: 20% vs 2% (p=.03).

Cross-trial synthesis: the recurrence-after-lavage finding is consistent and robust across both independent RCTs (~20-21% vs ~2-4%) — probably the most trustworthy single data point in this area so far. The short-term morbidity picture is not consistent: stark and trial-stopping in Ladies, absent by SCANDIV’s 5-year report. Not yet clear whether this is a real discordance (different patient selection, different Hinchey III confirmation protocols) or an artifact of different endpoints/timepoints — flagged as an open question, see SCANDIV Trial for detail.

Guideline positions diverge:

• ASCRS (2020) — strong recommendation for resection over lavage in purulent peritonitis.
• ESCP — considers lavage feasible in selected Hinchey III patients.

Framed by both trials’ authors as a shared-decision-making trade-off (lower stoma risk vs. higher reoperation/recurrence risk, and in Ladies trial’s case, higher short-term morbidity) rather than a settled question.

A recurring theme across both papers: Hinchey III (purulent) vs. IV (fecal) peritonitis cannot be reliably distinguished preoperatively or even at limited intraoperative exploration — a meaningful share of lavage “failures” in both trials trace back to misdiagnosed fecal peritonitis or an underlying perforated carcinoma. Both papers suggest CT with rectal contrast as an unproven potential fix, not routinely used.

Hartmann’s procedure vs. primary anastomosis (given resection is happening)

A distinct question from lavage-vs-resection above: once the decision is made to resect, should the surgeon end with a stoma (Hartmann’s) or restore continuity (primary anastomosis, ± defunctioning ileostomy)? The LADIES DIVA trial (Lambrichts 2019 - LADIES DIVA Trial) gives a clear answer, in contrast to the more contested lavage-vs-resection debate: primary anastomosis strongly favored — 12-month stoma-free survival 94.6% vs 71.7% (HR 2.79, p<0.0001) in hemodynamically stable, immunocompetent patients under 85. Benefit held (and was even larger) in Hinchey IV (fecal peritonitis) vs. Hinchey III, with no difference in short-term morbidity/mortality after the index procedure, and notably lower morbidity after stoma reversal with primary anastomosis (8% vs 30%) — reversing an ileostomy is a simpler procedure than reversing a Hartmann’s colostomy. This is the wiki’s first source covering Hinchey IV disease specifically.

Uncomplicated (non-perforated) diverticulitis

Per Sabiston Ch52 - Diverticular Disease, Obstruction & Pseudo-Obstruction (textbook reference, not primary literature): individualized outpatient management is now standard for most cases.

• Antibiotics controversy: a systematic review/meta-analysis found no benefit from antibiotics in uncomplicated diverticulitis, prompting some clinicians to stop prescribing them routinely — described as an evolving practice shift rather than a settled guideline mandate. No primary trial data on this specific question is in the wiki yet (see open items).
• Colonoscopy recommended 4–8 weeks after recovery to rule out an underlying malignancy.
• Recurrence after a first uncomplicated episode: 10–35%.

Elective surgery timing/indications

Indications have shifted away from the old “number of prior attacks” threshold toward individualized assessment (severity, comorbidity, QoL impact). This also overturns the older teaching that patients under 50 have more “virulent” disease warranting resection after a single uncomplicated episode — current evidence does not show elevated recurrence or emergency-surgery rates in younger patients, and current guidelines do not recommend treating them differently.

Special populations

• Right-sided diverticulitis — common in Asian populations, rare in the West; can mimic acute appendicitis; recurrent/complicated disease or diagnostic uncertainty favors resection (right hemicolectomy).
• Immunocompromised patients (transplant, diabetes, renal failure/cirrhosis, steroids/ chemotherapy) — similar baseline prevalence of diverticulitis, but more likely to present with free perforation and complicated disease due to blunted inflammatory response; lower threshold for resection after a single attack; primary anastomosis generally avoided if emergency resection is required, given impaired healing/immune status.

Open items / gaps

• No primary trial data yet on the antibiotics-vs-no-antibiotics question for uncomplicated diverticulitis — only the textbook chapter’s characterization of a systematic review. Worth finding and ingesting that review directly.
• DILALA and LapLAND trial data are referenced in ingested trials’ discussions but not yet ingested as their own sources — see SCANDIV Trial open items.
• Resolve (or find a source that resolves) the short-term-morbidity discordance between Ladies LOLA and SCANDIV noted above.
• Patient selection criteria for primary anastomosis (hemodynamic stability, immunocompetence, age <85) come from DIVA’s inclusion/exclusion criteria — not yet cross-checked against other guideline sources (e.g. ASCRS) for consistency.
• Colovesical fistula management (mentioned in Sabiston as typically requiring resection with fistula takedown) not yet covered in depth — no dedicated source.