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Toronto Notes 2019 Diverticular Disease Diverticular Disease
Definitions
• diverticulum:abnormalsac-likeprotrusionfromthewallofaholloworgan
• diverticulosis:presenceofmultiplediverticula
• diverticulitis:inflammationofdiverticula
• true(congenital)diverticuli:containalllayersofcolonicwall,oftenright-sided • false(acquired)diverticuli:containmucosaandsubmucosa,oftenleft-sided
General Surgery and Thoracic Surgery GS31
TRUE DIVERTICULUM (full wall thickness)
FALSE DIVERTICULUM (mucosal herniations)
Mucosa
Circular muscle Mesocolon Mesenteric tenia
Figure 13. Diverticular disease – cross-sections of true and false diverticuli
Diverticulosis
Epidemiology
• 5-50%ofWesternpopulation,lowerincidenceinnon-Westerncountries,M=F • prevalenceisagedependent:<5%byage40,30%byage60,65%byage85
• 95%involvesigmoidcolon(siteofhighestpressure)
Pathogenesis
Antimesenteric tenia
Diverticulosis vs. Diverticulitis
Diverticulosis represents the presence of diverticuli (bulging pouches) within the colonic wall, whereas diverticulitis is the inflammation of one or more diverticuli
• riskfactors
■ lifestyle: low-fibre diet (predispose to motility abnormalities and higher intraluminal pressure),
inactivity, and obesity
■ muscle wall weakness from aging and illness (e.g. Ehler-Danlos, Marfan’s)
• highintraluminalpressurescauseoutpouchingtooccuratpointofgreatestweakness,mostcommonly where vasa recta penetrate the circular muscle layer, therefore increased risk of hemorrhage
Clinical Features
• uncomplicateddiverticulosis:asymptomatic(70-80%)
• episodicabdominalpain(oftenLLQ),bloating,flatulence,constipation,diarrhea • absenceoffever/leukocytosis
• nophysicalexamfindingsorpoorlylocalizedLLQtenderness
• complications
■ diverticulitis (15-25%): 25% of which are complicated (i.e. abscess, obstruction, perforation, fistula) ■ bleeding (5-15%): PAINLESS rectal bleeding, 30-50% of massive LGIB
■ diverticular colitis (rare): diarrhea, hematochezia, tenesmus, and abdominal pain
Treatment
• uncomplicateddiverticulosis:highfibre,education • diverticularbleed
■ initially workup and treat as any LGIB
■ if hemorrhage does not stop, resect involved region
Diverticulitis
Epidemiology
• 95%left-sidedinpatientsofWesterncountries,75%right-sidedinAsianpopulations
Pathogenesis
• erosionofthewallbyincreasedintraluminalpressureorinspissatedfoodparticles→inflammationand focal necrosis → micro or macroscopic perforation
• usuallymildinflammationwithperforationwalledoffbypericolicfatandmesentery;abscess,fistula,or obstruction can ensue
• poorcontainmentresultsinfreeperforationandperitonitis
© Sonya Amin 2003