Diagnosis and management of acute diverticulitis.

Uncomplicated diverticulitis is localized diverticular inflammation, whereas complicated diverticulitis is diverticular inflammation associated with an abscess, phlegmon, fistula, obstruction, bleeding, or perforation. Patients with acute diverticulitis may present with left lower quadrant pain, tenderness, abdominal distention, and fever. Other symptoms may include anorexia, constipation, nausea, diarrhea, and dysuria. Initial laboratory studies include a complete blood count, basic metabolic panel, urinalysis, and measurement of C-reactive protein. Computed tomography, the most commonly performed imaging test, is useful to establish the diagnosis and the extent and severity of disease, and to exclude complications in selected patients. Colonoscopy is recommended four to six weeks after resolution of symptoms for patients with complicated disease or for another indication, such as age-appropriate screening. In mild, uncomplicated diverticulitis, antibiotics do not accelerate recovery, or prevent complications or recurrences. Hospitalization should be considered if patients have signs of peritonitis or there is suspicion of complicated diverticulitis. Inpatient management includes intravenous fluid resuscitation and intravenous antibiotics. Patients with a localized abscess may be candidates for computed tomography-guided percutaneous drainage. Fifteen to 30 percent of patients admitted with acute diverticulitis require surgical intervention during that admission. Laparoscopic surgery results in a shorter length of stay, fewer complications, and lower in-hospital mortality compared with open colectomy. The decision to proceed to surgery in patients with recurrent diverticulitis should be individualized and based on patient preference, comorbidities, and lifestyle. Interventions to prevent recurrences of diverticulitis include increased intake of dietary fiber, exercise, cessation of smoking, and, in persons with a body mass index of 30 kg per m(2) or higher, weight loss.