The treatment of diverticulitis is based on the severity of the attack. Mild attacks (when a patient has abdominal pain and mild fever but can tolerate liquids and light foods) can be treated with oral antibiotics and as an outpatient. Moderate to severe attacks often require hospital admission. Intravenous fluids and antibiotics are administered, the patient is given bowel rest, and most patients see improvement in 48-72 hours. Patients are prescribed a low residue diet for a few weeks to allow the colon swelling to resolve. Then they are started on a high fiber diet. If they have not had a colonoscopy, it is mandatory to schedule one in the next 8-12 weeks to rule out colon cancer mimicking diverticulitis.
Complicated diverticulitis is a moderate to severe attack that leads to complications. The most common complications include the formation of an abscess, fistula and colon stricture. An abscess is a pocket of bacteria that can form in the wall of the colon, or distant to the area of micro-perforation. A fistula is an abnormal communication from the perforation to another structure such as the bladder or vagina. A stricture is a narrowing of the colon lumen due to chronic scarring, leading to a bowel obstruction. As mentioned before, free perforation, while not a complication per se, mandates surgery.
Surgical treatment is reserved for complicated diverticulitis, free perforation or recurrent attacks impacting a patient’s quality of life. Once a patient is having multiple attacks, there is a high likelihood of continued attacks. The idea in multiple recurrent attacks is to perform surgery electively prior to the development of complications. Patients who meet criteria are referred to surgeons for evaluation, and a risk—benefit calculation is performed to assess the outcome of potential surgery. It is not ideal not to operate emergently. If possible, surgery should be elective, which allows the inflammation to subside from the attack of acute diverticulitis. This reduces complications.
The surgery requires removal of the diseased segment of bowel, often easily seen intraoperatively as chronic wall thickening and signs of chronic inflammation, and then reconnecting the two healthy ends of bowel. The case may be performed laparoscopically or open, depending on surgeon’s training and experience. Laparoscopic cases have lower complications rates. In elective cases, major complications occur less than 5% of the time, and disease recurrence is rare. The most common complication after colon resection is infection, which can be as high as 11%. Risk factors for wound infection include obesity, diabetes, smoking, and emergent surgery. If there is a wound infection, the treatment requires opening the wound and packing it daily until it heals.
Diverticulitis treatment medical expert witness specialties include gastroenterology, general surgery, pathology, colon-rectal surgery, immunology, internal medicine, family medicine, and hospitalist medicine.