Snapshot A 61-year-old man presents to the clinic for an annual wellness exam. He denies any specific concerns except for some constipation for the past week. His past medical history is significant for hypertension that is controlled with lisinopril. He denies fever, weight changes, melena, hematochezia, abdominal pain, or stool changes. He subsequently undergoes a routine colonoscopy which demonstrates small outpouchings within the sigmoid colon. Introduction Clinical definition condition of having multiple sac-like protrusions (diverticula) of the colonic wall that are not inflamed these diverticula can cause painless bleeding diverticulitis is defined as inflammation of a diverticulum Epidemiology Demographics prevalence increases with age with a prevalence of 60% by age 60 location of the diverticula varies by geography sigmoid colon is the most common location in Western countries predominately at the right side in Asian countries Risk factors age low dietary fiber high fat and red meat intake physical inactivity obesity ETIOLOGY Pathogenesis abnormal colonic motility leading to the colonic mucosa and submucosa to herniate through well-defined points of weakness at the muscle layer points of weakness correspond to where the vasa recta penetrate the circular muscle layer of the colon a typical colonic diverticulum is a “false diverticulum” and is only covered by serosa it is hypothesized that abnormal colonic motility causes increases in intraluminal pressure diverticular bleeding occurs due to segmental weakness of the vasa recta, as it is exposed to injury along its luminal aspect from the diverticulum Presentation Symptoms asymptomatic cramping bloating flatulence irregular defecation rectal bleeding Physical exam left lower quadrant (LLQ) pain and tenderness imaging Colonoscopy gold standard allows for visualization of diverticula and rule out of differential (e.g., malignancy) not recommended during an acute diverticulitis attack Computed tomography (CT) with contrast best for the evaluation of acute diverticulitis Plain abdominal radiograph may show signs of constipation rules out other causes of abdominal pain (e.g., small bowel obstruction) Studies Diagnostic testing diagnostic approach diagnosis is often incidental during other investigations and is confirmed via colonoscopy studies laboratory studies CBC and iron studies for evaluation of anemia secondary to blood loss Differential Diverticulitis differentiating factors will present clinically with severe abdominal pain and fever Colon/rectal cancer differentiating factors may complain of symptoms (e.g., stool changes) and the lesion will be present on colonoscopy Treatment As diverticulosis often presents asymptomatically, no specific treatment is needed First-line observation lifestyle changes high-fiber diet to prevent constipation In the case of diverticular bleeding resuscitation (e.g., IV fluids and blood products) colonoscopy with cauterization if bleeding is not identified with colonoscopy, then angiography is indicated surgery is the last resort if the bleeding cannot be controlled with colonoscopy or angiography Complications Anemia Bleeding/hemorrhage Exsanguination Diverticulitis