Crohn’s disease is a form of chronic inflammation of the bowel, the cause of which remains unknown.
The small bowel is that part of the intestine between the stomach and duodenum above, and the colon below. Its function is to digest food and absorb it. It both secretes fluid into the bowel and absorbs it. Some parts of the small bowel have quite specialised tasks. For instance, the oast part – the terminal ileum – is responsible for absorbing vitamins A, D, E and K and also bile salts.
Most patients with small bowel Crohn’s disease will eventually need surgery, but surgery is reserved for specific indications. Surgery can never cure small bowel Crohn’s disease.
Indications for surgery
If you are reading this leaflet, it is probably because your doctor has recommended surgery. This may be because you have narrowing of the small bowel caused by the Crohn’s disease (strictures). These usually cause crampy pain, most often located in the middle of the abdomen, around the belly button. Sometimes they will cause nausea or even vomiting. Patients with strictures may also have altered bowel habit, either constipation or diarrhoea, though the latter is more common.
Another indication for surgery is the development of a fistula. This is an abnormal connection between the small bowel and another area. The fistula may connect the bowel to the skin, often through a wound (called an entero-cutaneous fistula). This will result in bowel content reaching the skin surface where it can cause irritation.
Alternatively, the fistula may communicate with the bladder, causing bladder infections (urinary tract infection or cystitis). Sometimes in women it will communicate with the vagina (front passage) causing a vaginal discharge. Lastly, it may connect with another bit of bowel. This may cause no symptoms at all, or may cause diarrhoea.
A few patients wit Crohn’s disease get a perforation of the bowel. This may occur suddenly, causing severe abdominal pain and even peritonitis. Here, urgent surgery is required. In other cases, the perforation develops more slowly and results in an abscess. This will result in a fever and localised pain.
Bleeding is not as common in small bowel Crohn’s disease as it is in Crohn’s colitis (which affects the large bowel), but it can occur.
In children, Crohn’s disease of the small bowel may cause “failure to thrive”, where growth is not as rapid as expected. This is occasionally an indication for surgery.
Be sure that you understand:
We suggest that you discuss the circumstances that have led your surgeon to recommend surgery in your case.
What is done at the operation:
Operations for small bowel Crohn’s disease can be divided into two types:
- Resections
- Strictureplasties
Resections involve removal of a length of bowel affected by Crohn’s disease. Usually the ends of the remaining bowel are rejoined. This join is called an anastomosis.
When the narrow segment of bowel is short, it may be possible to widen it without removing any bowel. This is strictureplasty. The bowel is opened along its length and the open is then sewn up across the long axis of the bowel.
Sometimes multiple strictureplasties or resections are needed. Indeed the two procedures may be performed in different parts of the small bowel during one operation.
What are the complications of surgery?
Any operation on the bowel carries risks. These are greater if you are very ill, particularly if you have lost a lot of weight, or if you have an infection, such as an abscess.
I other words, sick people have more difficult and therefore more risky operations, but they need them!
The major worry is leakage from the anastomosis (remember those are the places where the bowel is joined up). If these leak you get very sick. You may be lucky and just develop an abscess which can be drained. In some cases you can get peritonitis because the leak occurs into the abdomen and is not sealed off. This is a very serious and sometimes life-threatening complication that requires urgent surgery and often results in a stoma (an ileostomy) where the bowel is brought out onto the skin of the abdomen.
Other complications are similar to any abdominal operation. Wound infections are quite common. Clots in the leg veins can occur and rarely can dislodge and travel to the lung to cause a pulmonary embolism.
Ask your surgeon about the risks of surgery – it is important that you understand these.
If a lot of bowel is removed, either at a single operation or as a result of several lesser operations, the bowel may be too short to function normally. This can cause difficulty absorbing food, salts and water. For this reason surgeons tend to recommend surgery for small bowel Crohn’s disease only when it is the only option.
Will the Crohn’s disease recur?
The answer is “probably”. If you doctor was to look really hard for recurrent Crohn’s disease, he would find some evidence of recurrence in three out of four cases in the first three years after surgery.
By the time five years have elapsed, troublesome symptoms of recurrent Crohn’s disease will occur in about one third of cases. Most people can continue to be managed using medicines rather than further surgery.
About half of all patients will find that they need another operation within 20 years. So Crohn’s disease almost always recurs. It might require further medical treatment; it sometimes causes troublesome symptoms and eventually may need another operation.
What can I do to prevent recurrence?
The most important thing to remember is that your Crohn’s disease is not your fault! However, you can do some things to help reduce the risk of recurrence and of further surgery.
- Do not smoke. Smoking is a potent cause of recurrence of Crohn’s disease.
- Take your medicines, even if you are feeling well.
- There is good evidence that regular use of 5ASA medications, such as mesalazine, reduces the risk of recurrence.