COLONIC DIVERTICULAR DISEASE

INCIDENCE & EPIDEMIOLOGY

½ of individuals >60y/o 20% of patients develop symptomatic disease Western population ½ of individuals >60y/o 20% of patients develop symptomatic disease United States >200,000 hospitalization annually 5th most costly GI disorder Mean hospital stay: 9.7 days Average cost: $42,000/patient Mean age at presentation: 59 years F=M, men present at younger age

Rare, diets include more fiber and rough-age Underdeveloped countries Rare, diets include more fiber and rough-age However, shortly following migration in the U.S., immigrants will develop diverticular disease at the same rate as U.S. natives Philippines Extrapolated prevalence: 634,130 out of 86,241,697 (population estimated)* Extrapolated incidence: 95,119 out of 86,241,697 (population estimated)* * US Census Bureau, International Data Base, 2004 ( the extrapolations for Diverticular Disease are only estimates and may have limited relevance to the actual incidence of Diverticular Disease in any region)

TYPES OF COLONIC DIVERTICULAR DISEASE

TYPES TRUE DIVERTICULA FALSE DIVERTICULA involves only protrusion of the mucosa through the muscularis propria of the colon most common TRUE DIVERTICULA a saclike herniation of the entire bowel wall

PATHOPHYSIOLOGY

PATHOPHYSIOLOGY Protrusion occurs at the point where the NUTRIENT ARTERY or VASA RECTI penetrates through the muscularis propria Break in the integrity of the colonic wall Compression or erosion PERFORATION BLEEDING

PATHOPHYSIOLOGY commonly affect the SIGMOID COLON due to: Relative high pressure zone within the muscular sigmoid colin. Higher amplitude contractions combined with constipated, high fat content stool within the sigmoid lumen results in the creation of these diverticula Related to retention of particulate material within the diverticular sac and formation of fecalith

Diverticular bleeding Presentation, Evaluation, and Management

Diverticular Bleeding Hemorrhage from a colonic diverticulum is the most common cause of hematochezia in patients >60 years. Only 20% of patients with diverticulosis will have GI bleeding. Most bleeds are self-limited and stop spontaneously with bowel rest. Lifetime risk of rebleeding: 25% At Increased Risk For Bleeding Hypertension (+) (+) Atherosclerosis Regular NSAID use

Diverticular Bleeding Colonoscopy To localize the bleeding May be both diagnostic and therapeutic in the management of mild to moderate diverticular bleeding Angiography Management of massive bleeding in a stable patient Mesenteric angiography can localize the bleeding site and occlude the bleeding vessel successfully with a coil in 80% of the cases Follow up: Repetitive colonoscopy to look for evidence of colonic ischemia Segmental resection of the colon To eliminate risk of further bleeding In patients on chronic blood thinners

Diverticular Bleeding Highly selective coil embolization Rate of colonic ischemia: <10% Risk of acute rebleeding: <25% Selective infusion of vasopressin To stop hemorrhage Complications: MI, intestinal ischemia Recurrence of bleeding in 50% of patients once infusion is stopped

Diverticular Bleeding Surgery Indications: if patient is unstable or has had a 6-unit bleed within 24 h Total abdominal colectomy Patients with presumed bleeding from diverticular disease requiring emergent surgery without localization Rationale: Colonic diverticulosis is more often seen from the R colon Surgical resection with primary anastomosis In patients without severe comorbidities A higher anastomotic leak rate has been reported in patients who received >10 units of blood

Diverticulitis Presentation, Evaluation, and Management

DIVERTICULITIS Uncomplicated – 75% Complicated – 25% Abdominal Pain Fever Leukocytosis Anorexia/obstipation Complicated – 25% Abscess 16% Perforation 10% Stricture 5% Fistula 2% Presentation of Diverticular Disease

Diverticulitis Diverticular perforation Generalized peritonitis in <25% of cases (+) Abdominal distention Giant diverticulum of the sigmoid (+) Air fluid level in the LLQ on plain abdominal film Mx: resection to avoid impending perforation

Diverticulitis Diagnosis is best made on CT. CT Scan Findings Sigmoid diverticula Thickened colonic wall >4mm Inflammation within the pericolic fat ± collection of contrast material or fluid

Diverticulitis Suspected diverticulitis that does not meet CT criteria or is not associated with a leukocytosis or fever is not diverticular disease Conditions that mimic diverticular disease: IBS Ovarian cyst Endometriosis Acute appendicitis PID

Diverticulitis Barium enema or colonoscopy Should be performed ~6 weeks after an attack of diverticular disease A sigmoid malignancy can masquerade as diverticular disease. Should not be performed in the acute setting Higher risk of colonic perforation associated with insufflation or insertion of barium-based contrast material under pressure.

Diverticulitis Complicated diverticular disease Diverticular disease associated with an abscess or perforation, and less commonly with a fistula. With fistula formation Common locations include cutaneous, vaginal or vesicle fistulae Present with either passage of stool through skin or vagina, or pneumaturia Colovaginal fistulae: more common in women who have undergone hysterectomy Pneumaturia – presence of air in the urinary stream

Hinchey Classification of Perforated Diverticular Disease Stage I: perforated diverticulitis with a confined paracolic abscess Stage II: perforated diverticulitis that has closed spontaneously with distant abscess formation Stage III: noncommunicating perforated diverticulitis with fecal peritonitis (the diverticular neck is closed off and therefore contrast will not freely expel on radiographic images) Stage IV: perforation and free communication with the peritoneum, resulting in fecal peritonitis

Medical Management of Diverticular Disease Asymptomatic Diet alterations – fiber-enriched diet, including 30g of fiber/day Supplementary fiber products: Metamucil, Fibercon, Citrucel Avoid nuts and popcorn – may obstruct the lumen of the diverticulum Asymptomatic – discovered only on imaging studies or at the time of colonoscopy

Medical Management of Diverticular Disease Symptomatic Radiographic and hematologic confirmation of inflammation and infection within the colon Treated initially with antibiotics and bowel rest TMP-SMX or ciprofloxacin and metronidazole (+) Ampicillin – for nonresponders Alternative: IV piperacillin or oral penicillin/clavulinic acid Usual course: 7-10 days Rifixamin + fiber – less frequent recurrent symptoms from uncomplicated diverticular disease Limited diet until pain resolves Medical therapy can be continued beyond 2 attacks without an increased risk of perforation requiring a colostomy, especially in those >50 years. Asymptomatic – discovered only on imaging studies or at the time of colonoscopy TMP-SMX or cipro + metro – target aerobic gram – rods and anaerobic bacteria; do not cover enterococci, so ampicillin is added to regimen for nonresponsders

Surgical Management of Diverticular Disease In patients who are low risk (ASA I and II) who have had at least 2 documented attacks requiring hospitalization or those who do not rapidly improve on medical therapy Younger patients – more aggressive form of disease Waiting beyond two attacks is not recommended. In all low surgical risk patients with complicated diverticular disease

Surgical Management of Diverticular Disease Goals of Surgical Management Control sepsis Eliminate complications such as fistula or obstruction Remove diseased colonic segment Restore intestinal continuity

Surgical Management of Diverticular Disease

Surgical Management of Diverticular Disease Open or laparoscopic sigmoid resection – current option of uncomplicated diverticular disease Benefits of laparoscopic over open resection: Early discharge (by at least 1 day) Less narcotic use Earlier return to work Benefits of open over laparoscopic resection: Shorter operative procedure Less costly Complication rates are similar.

Surgical Management of Complicated Diverticular Disease Proximal diversion of the fecal stream with an ileostomy or colostomy and sutured omental patch with drainage Resection with colostomy and mucus fistula or closure of distal bowel with formation of a Hartmann’s pouch Resection with anastomosis (coloproctostomy) Resection with anastomosis and diversion (coloproctostomy with loop ileostomy or colostomy)

Surgical Management of Diverticular Diseases Hinchey Stages I and II Percutaneous drainage followed by resection with anastomosis about 6 weeks later Percutaneous drainage For abscesses ≥ 5 cm with a well-defined wall that is accessible If <5cm, may resolve with antibiotics alone Contraindications to percutaneous drainage: No percutaneous access route Pneumoperitoneum Fecal peritonitis

Surgical Management of Diverticular Diseases Hinchey Stages I and II If patients develop generalized peritonitis  Hartmann’s procedure Nonoperative therapy – 20% recurrence rate at 2 years in patients with Hinchey Stage I disease 80% of patients with Hinchey Stage II required surgical resection for recurrent symptoms.

Surgical Management of Diverticular Diseases Hinchey Stage III Hartman’s procedure or with primary anastomosis and proximal diversion If patient has significant comorbidities: intraoperative peritoneal lavage (irrigation), omental patch to the oversewn perforation, and proximal diversion of the fecal stream with either an ileostomy or transverse colostomy can be performed Hinchey Stage IV No anastomosis of any type should be attempted.

Recurrent Symptoms in Diverticular Disease Occurs in 10% of patients. Recurrence develops in patients following inadequate surgical resection. A retained segment of diseased rectosigmoid colon is associated with twice the incidence of recurrence. IBS – may also cause recurrence of initial symptoms Patients undergoing surgical resection for presumed diverticulitis and symptoms consistent with IBS have functionally poorer outcomes.