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In the belly of the beast
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The puzzling causes and debilitating effects of inflammatory bowel disease
By Dr. Alan Thomson
It was over 20 years ago, but I will never forget the patient who was half-carried into the Edmonton clinic. Although he was well over six feet tall, he weighed less than one hundred pounds. He and his family were terrified and no wonder. At 25 years of age, he was literally wasting away. It was horrifying to see someone so emaciated and weak that he had to be helped into the examining room. As a young physician just starting my specialty practice in diseases of the digestive tract, I had rarely seen someone his age so sick. Treating him strengthened my resolve to do whatever I could to help patients who, like him, suffer the ravages of inflammatory bowel disease (IBD).
IBD — the slow starvation
Inflammatory bowel disease is characterized by inflammation and/or ulcers (sores) on portions of the digestive tract. There are two types of IBD, Crohn’s disease and ulcerative colitis. Crohn’s disease is spotty and can appear throughout the entire digestive tract from mouth to anus, whereas ulcerative colitis is found only in the lower bowel. In both forms of IBD, inflammation and ulceration cause significant pain and inhibit the gut’s ability to absorb nutrients. The result is weight loss and fatigue, and if the ulcerations are left unchecked, life-threatening infection and bleeding. Patients with ulcerative colitis are also at higher risk for cancer of the colon and liver.
IBD is now thought of as an immune disorder, in which the body’s immune system wrongly identifies some component as a foreign invader rather than part of the body, and marshals an immune response in defense. IBD can strike anyone at any age but is most frequently diagnosed in women aged 20 to 40. Whether this disorder is genetic or environmentally caused is not yet clear. We do, however, see some family clusters, which suggests that a genetic predisposition may exist which is then triggered by an environmental factor. Whether this environmental factor is a chemical pollutant, a food, a viral or bacterial exposure or infection, a combination of these, or something else entirely different, is unknown.
What is disturbing is that Canada’ s rate of IBD is the highest in the world, with 100 patients per 100,000 population. This calculates to about 28,000 patients each with Crohn’s disease and ulcerative colitis. Studies have shown that Asians who move to Canada develop IBD in the same percentage as other Canadians, pointing to environmental factors as a major factor, regardless of genetic predisposition or family history.
Intestinal footage
Most of us don’t think too much about the fate of the tuna salad sandwich after it heads down the hatch. But when you consider how efficiently the body turns a meal into nutrients that both fuel our activities and form the building blocks of our every cell, it’s a pretty remarkable journey – and a long one too. It takes six yards of small bowel and three yards of large bowel to complete the process. After food is dissolved by stomach acids, it passes through the small bowel, where the nutrients enter the blood stream. Then the sludgy waste material passes through the large bowel, where most of the water is extracted. In a semi-solid form, the material comes to rest in the rectum until it’s eliminated by having a bowel movement.
This entire process is possible because the gut is lined with specialized mucous that is not itself corroded by the stomach acids. In the IBD patient, however, the mucous becomes disturbed or corroded, allowing the highly acidic digested food to irritate and inflame the intestinal tissue, as well as leaving it open to infection. As a result, nutrients are not absorbed properly, leading to weight loss and fatigue. The inflammation and infection cause fever and pain, and lead to the formation of scar tissue which can obstruct and bind loops of bowel with stringy tissue. All of this can create more problems in passing stool, and lead to more pain.
Beyond Immodium
At first, most patients wait to see if the diarrhea, constipation, and fatigue go away on their own. When the frequent bouts of diarrhea reach around twenty per day and daily activities at home and work are disrupted, most people realize it’s time to visit the doctor. Severe, disabling cramps that last for hours along with alternating constipation, rectal bleeding, and an urge to pass stool although none is present are part of IBD. Skin rashes and joint pain are also common, in addition to infection, fever, low red blood cell count (anemia), and fatigue. When patients do seek help, it can typically take about a year to sort through the symptoms and get to a final diagnosis. Tracing which symptoms belong to which aspect of the disease and finding appropriate treatments is no small challenge.
To confirm IBD, the specialist in gastroenterology or internal medicine looks at an X-ray of the gut and sample of bowel tissue. The sample is taken by sigmoidoscopy or colonoscopy, which involves passing a fibreoptic instrument through a thin, flexible tube into the lower or upper bowel while the patient is sedated. Once a confirmed diagnosis is made, the sooner optimal treatment can be started the better. Patients are encouraged to contact the Crohn’s and Colitis Foundation of Canada to be referred to local chapter groups. These networks are invaluable. As with any chronic illness, being sick and in pain is stressful and depressing, which can make symptoms worse.
The no-fault illness
One of my most important tasks as a treating physician is to assure patients that having IBD is not their fault. Although stress is often classified as an environmental factor, having a high-strung personality does not cause IBD. There is a great deal of unpredictability as to who gets IBD, what course the disease will take, and what treatment options will bring the best results. Even IBD patients who work hard to eliminate possible trigger foods find that they can’t prevent relapse. That’s why emotional support from both the family and the health care team is so important.
Luckily, to be diagnosed with IBD today is not as fearful as it once was. Advances in diagnosis and treatment are so significant that most patients are helped early on in the course of their illness, and can be assured that they will be able to live relatively normal lives. They can work, pursue their goals, and have children. However, their illness will visit as an unwelcome and unpredictable guest for which drug therapy and/or surgery may be necessary. When relapses do occur, we can now offer a range of treatments to initiate and sustain remission (periods of normal bowel function).
Everyone touched by IBD wants to know two things: the cause and the cure. Research sometimes takes us up a blind alley, but ultimately I believe it will give us answers, longer periods of remission and one day, an end to IBD.
Treating IBD
Anti-inflammatories:
• Azulfidine: usually the first anti-inflammatory drug the patient takes; it maintains remission in mild to moderate cases.
• 5-ASA: (5-aminosalicylic acid, or mesalamine), a powerful anti-inflammatory drug related to Aspirin.
• Steroids and corticosteroids: powerful anti-inflammatory drugs used in severe cases. While the side effects can be very serious, the drugs are so important to initiating remission that researchers continue to improve them for IBD use. One new entry is budesonide (marketed as Entocort capsules) which is a marked advance for Crohn’s disease, due to the reduced side effects.
Immunosuppressives:
• Immunosuppressive drugs: suppress an over-active immune system. Side effects include risk of infection and reduced production of blood cells due to suppressed bone marrow.
Antibiotics:
• Used to treat infection.
Surgery
In a small percentage of patients, drug treatments are not enough. If intestinal sores don’t heal, quality of life is seriously compromised and the patient is also at risk for life-threatening bowel perforation, massive bleeding and infection. New improvements in surgical techniques can often help.
• In Crohn’s disease, surgeons can now remove the portion of diseased small intestine and reconnect the cut ends (anastomosis). Frequently, the patient can resume a near-normal life.
• In some cases of ulcerative colitis, it is now possible to remove the large intestine and attach the end of the small intestine to the anus, creating an internal ‘pouch’ to substitute for the rectum, enabling patients to pass stool in the usual way.
• In ulcerative colitis, removal of the lower bowel and rectum is regarded as the last resort. Stool passes through an opening, called an ostomy, that the surgeon creates in the lower abdomen, and is collected in a discrete bag (ostomy pouch). With the range of ostomy supplies now available, many patients can have sex, play sports and even swim comfortably.
Dr. Alan Thomson is a Clinical Gastroenterologist in Edmonton and a teacher at
the University of Alberta, medical faculty.
The Crohn’s and Colitis Foundation of Canada is the largest sponsor of IBD research in the country, with 75 community-based chapters and resources. Call 1-800-387-1497 for the nearest group or visit the website at www.ccfc.ca
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