Learn more about Diverticular disease and diverticulitis
Diverticular disease refers to the presence of diverticuli in the colon. A diverticulum is simply a pocket or an out-pouching that occurs at a site of relative weakness. These can be considered a consequence of wear-and-tear in the bowel, akin to pot-holes in the road.
In a Western population, diverticular disease is very common – almost like having wrinkles. It is present in 10% of those age 40 and increases to over 50% at age 60. It is believed that our modern diet has a chronic lack of fibre. This results in a less bulky stool, and the bowel then has to work harder and exert higher pressures to move the stool through the colon. Over time, these increased pressures result in the formation of a thick muscular bowel wall, and eventually diverticuli form at sites of weakness.
There is much confusion about the terminology related to diverticular disease. The presence of pockets is called either: diverticular disease, diverticulosis, diverticulum or colloquially – ‘tics’. These all mean the same thing and in general, do not cause symptoms at this stage of the disease. Once formed, diverticuli do not disappear and most people suffer no ill-effects.
The usual recommendation for people with diverticular disease is to ensure adequate dietary fibre intake, and/or the use of a fibre supplement available from the pharmacist or supermarket (e.g. Metamucil, Benefibre, Nulax). The old advice to avoid grains, seeds or nuts have not been shown in large population studies to prevent complications, thus there is no good evidence that any particular foods should be avoided.
Diverticulitis is the most common complication of diverticular disease and occurs in approximately 15%. Diverticulitis refers to infection or inflammation associated with one or more of these pockets. This typically causes pain, most often in the left lower abdomen and the pain may be worse with movement. Severe cases are associated with more generalised and severe abdominal pain, fevers, loss of appetite and feeling unwell.
Uncomplicated diverticulitis may be managed in hospital or at home. Emerging evidence suggests that straight-forward diverticulitis may not require antibiotics, however, it has been traditionally treated with antibiotics. Antibiotics may still be used depending on the severity of the attack, findings on a CT scan, or depending on age or other medical conditions. The chance of a second attack of diverticulitis is about 30%.
Complicated diverticulitis refers to the additional presence of an abscess or an unconfined leak or perforation in the bowel. This also results in pain and can have additional signs such as fevers, sweats and becoming more unwell. This may require antibiotics alone, drainage of any abscess, and sometimes emergency surgery.
Surgery for diverticulitis may be considered for recurrent attacks of diverticulitis. Alternatively, it will be discussed after an episode of complicated diverticulitis. It may be done in an elective setting when the inflammation has settled, or sometimes required as an emergency procedure but fortunately, this is uncommon.
Surgery may require a washout and/or removal of the affected segment of the bowel. Depending on the severity of the illness, sometimes it may not be safe to join the bowel back together, and a colostomy or bowel bag may need to be formed. This delivers waste onto the abdominal wall and is collected in a stoma. A stoma is avoided when safe and possible.
Elective surgery for diverticulitis depends on individual patient circumstances and needs to be discussed.
As a follow-up for diverticulitis, a colonoscopy is often performed. This is to confirm the presence of diverticular disease and often used as an opportunity to exclude the presence of bowel polyps and even bowel cancers. In uncomplicated diverticulitis, there seems to be no particular increased risk for bowel polyps or cancer.
Diverticular disease may also account for rectal bleeding. This is usually dark-red/maroon and may be quite heavy, requiring hospital admission. Approximately 90% of the time, this bleeding will stop, but on occasion requires intervention. Any rectal bleeding warrants investigation by a colorectal surgeon.