Chapter 44. Diverticulitis

Diverticular disease is a common GI disorder that occurs when small herniations through the wall of the colon, or diverticula, become inflamed or infected.

Clinical Features

The most common symptom is a steady, deep discomfort in the left lower quadrant of the abdomen. Other symptoms include tenesmus and changes in bowel habits, such as diarrhea or increasing constipation and nausea/vomiting. Urinary tract symptoms are less common. Patients with a redundant sigmoid colon, of Asian descent, or with right-sided disease may complain of pain in other abdominal regions, including the right lower quadrant. The presentation can mimic other diseases, such as appendicitis. Half of patients will describe a similar prior episode.

Patients have a low-grade fever, but the temperature may be higher in patients with generalized peritonitis and in those with an abscess. Physical findings range from mild abdominal tenderness to severe pain, obstruction, and peritonitis. Occult blood may be present in the stool. A pelvic examination should be performed in female patients to exclude a gynecologic source of symptoms.

Diagnosis and Differential

The differential diagnosis includes acute appendicitis, colitis (ischemic or infectious), inflammatory bowel disease (Crohn disease or ulcerative colitis), colon cancer, irritable bowel syndrome, pseudomembranous colitis, epiploic appendagitis, gallbladder disease, incarcerated hernia, mesenteric infarction, complicated ulcer disease, peritonitis, obstruction, ovarian torsion, ectopic pregnancy, ovarian cyst or mass, pelvic inflammatory disease, sarcoidosis, collagen vascular disease, cystitis, kidney stone, renal pathology, and pancreatic disease.

Diverticulitis can be diagnosed by clinical history and examination alone. In stable patients with past similar acute presentations, no further diagnostic evaluation is necessary unless the patient fails to improve with conservative medical treatment. If a patient does not have a prior diagnosis or the current episode is different from past episodes, diagnostic imaging should be performed to rule out other intraabdominal pathology and evaluate for complications. CT scan is the preferred imaging modality for its ability to evaluate the severity of disease and the presence of complications. CT with IV and oral contrast has documented sensitivities of 97% and specificities approaching 100%. Laboratory tests, such as a CBC, liver function tests, and urinalysis, are rarely diagnostic but may help exclude other diagnoses.

Emergency Department Care and Disposition

ED care begins with fluid and electrolyte replacement, pain and nausea control. Ill appearing patients, those with uncontrolled pain, vomiting, peritoneal signs, signs of systemic infection, comorbidities or immunosuppression, and those with complicated diverticulitis (eg, phlegmon, abscess, obstruction, fistula, or perforation) require admission and surgical consultation.

1. Place the patient on complete bowel rest. Opiates, such as morphine 0.1 milligram/kilogram IV, may be required for pain. Nasogastric suction may be indicated in patients with bowel obstruction or adynamic ileus.

2. Administer IV antibiotics to patients requiring admission. Options include metronidazole 500 milligrams IV with either ciprofloxacin 400 milligrams IV or levofloxacin 750 milligrams IV. Alternate single agent treatment options include ampicillin-sulbactam, 3 grams IV, piperacillintazobactam, 3.35 grams IV, ertapenem, 1 gram IV, ticarcillin-clavulanate, 3.1 grams IV or moxifloxacin, 400 milligrams IV. Patients with very severe disease may require extended broad-spectrum antibiotics such as imipenem 500 milligrams IV, meropenem 1 gram IV, or doripenem 500 milligrams IV.

3. Immunocompetent patients with uncomplicated diverticulitis who look well, have mild findings on physical examination and in whom pain is controlled with oral analgesia may be managed as outpatients with oral antibiotics for 7 to 14 days, on a clear liquid diet that is advanced as tolerated, and close follow-up (2 to 3 days). Patients should contact their physicians or return to the ED if they develop increasing abdominal pain or fever or are unable to tolerate oral intake.

Oral antibiotic regimens include metronidazole 500 milligrams every 8 hours plus either ciprofloxacin 500 milligrams every 12 hours or clindamycin 300 milligrams every 6 hours or trimethoprim-sulfamethoxazole DS, 1 tablet every 12 hours. Monotherapy includes amoxicillin-clavulanate 875 milligrams every 12 hours, and moxifloxacin, 400 milligrams PO once a day.