Crohn’s Disease Insights

Crohn’s Disease Insights2016-11-30T11:40:38+00:00

Crohn’s disease is a chronic inflammatory bowel disease that can affect any area of the gastrointestinal (GI) tract, from the mouth to the anus, either continuously or as isolated areas. The inflammation can involve the inner intestinal mucosal lining, up to the full thickness of the bowel wall, and consists of swelling, dilated blood vessels, and loss of fluid into the tissues. This can lead to a number of debilitating symptoms, such as chronic diarrhea, rectal bleeding, pain, and weight loss, as well as delayed development in children. Crohn’s disease can also manifest symptoms outside of the GI tract.

 

Ultrasounds vs. CT scans

Three Calgary physicians headlined a symposium in Banff, Alberta in March 20111 to discuss using transabdominal ultrasound (TAUS) instead of CT scans to diagnose, monitor, and evaluate Crohn’s disease patients. The physicians claim that TAUS is a much cheaper alternative (a TAUS machine costs about $250,000, whereas a CT scanner costs approximately $2.5 million) and would protect these patients – whose disease must be monitored regularly throughout their lives – from unnecessary and potentially cancer-causing radiation exposure. They claim that patients will be more likely to disclose their symptoms fully to their physicians if they are relieved of the radiation fears associated with undergoing CT scans.

Radiation absorbed by the body causes cell changes that may increase the risk of cancer and hereditary effects. Radiation is found in many forms. People are exposed to natural background radiation every day from the ground, building materials, air, food, outer space (cosmic rays), and even from elements occurring naturally in our bodies. A millisievert (mSv) is the unit used to measure the amount of radiation received. The amount of natural background radiation a person receives each year in Canada is 2-4 mSv.2 The added dose from cosmic rays during a coast-to-coast round trip flight in a commercial airplane is about 0.03 mSv.3

Currently, the North American standard of practice in gastroenterological imaging requires the use of radiologic exams, which can expose a patient to 6-8 mSv of radiation for each X-ray and 10-30 mSv of radiation for each CT scan.3 However, there are increasingly more studies about the unnecessary use of radiation exposure for management and treatment of chronic diseases, including Crohn’s disease. A recent article, published in the Canadian Medical Association Journal4, quantified the increase in cancer risk due to low radiation exposure at approximately 0.5% for women and 0.2% for men.

Ultrasound imaging, which does not emit radiation, has been used for decades and has an excellent safety record. However, even though there are no known risks of ultrasound imaging, it can produce effects on the body. When ultrasound enters the body, it heats the tissues slightly. In some cases, it can also produce small pockets of gas in body fluids or tissues (cavitation). Its heating properties have some therapeutic role in muscle rehabilitation but the long-term effects of tissue heating and cavitation are not known, and this is why it is discouraged unless medically necessary.

 

Medication – Combinations Work Best

There is a wide variety of anti-inflammatory medication available to help manage Crohn’s disease and, in many cases, to bring it into remission. The most common of these include 5-ASAs and corticosteroids. However, some individuals may not see results with one medication or be unable to tolerate another. Additional treatments for Crohn’s disease include immunosuppressive agents and biologics.

A randomized, double-blind trial, recently published in The New England Journal of Medicine,5 compared the efficacy of an immunosuppressive agent called Imuran® (azathioprine) alone, a biologic called Remicade® (infliximab) alone, and the two drugs combined. The study included 508 adults with moderate-to-severe Crohn’sdisease, who had not undergone previous immunosuppressiveor biologic therapy. Researchers randomly assigned patients to receive different doses and placebos. Results showed that a combination of azathioprine and infliximab, or infliximab alone, might be more effective in helping patients achieve corticosteroid-free clinical remission and mucosal healing after six months of treatment than when using azathioprine alone.

It is important to note that even though more individuals entered corticosteroid-free remission and experienced mucosal healing while combining the two medications, there is an increased risk of side effects with combined treatment, which might reduce the safety profile.

Studies such as these are useful to physicians, who can confidently try different combinations of treatments with patients to find the perfect mix of medications to bring a patient into remission. Your physician might suggest a course of treatment that is different from that of another person who has Crohn’s disease, as each person’s response to medication is unique.

 

Whole Foods Better Than Processed

Modern medical science does not know for sure the cause or causes of Crohn’s disease, but many believe that immune system dysregulation, previous bacterial infection, and genetic predisposition may all play a part. We know that the prevalence of Crohn’s disease is higher in developed countries, where many people eat a Western diet, which is often lower in plant fibres and higher in processed food products. There is even some recent evidence that as the Western diet became more common in Japan, rates of Crohn’s disease rose in that country. This suggests that diet plays at least a small role in the development of Crohn’s disease.

A recent small study, published in the journal, Gut6, analyzed the effects of soluble plant fibres and a food additive called polysorbate-80 on certain cells responsible for allowing Escherichia coli (E. coli) into the cell (translocation). Polysorbate-80, an emulsifier, stabilizer, and surfactant, is a viscous, water-soluble yellow liquid used in many common products, including ice cream, condiments, chewing gum, whipped toppings, vitamins, pickled foods, medications and vaccines, as well as several creams and lotions.7 The product is a derivative of sorbitol and oleic acid.

Researchers used biopsies from the colonic mucosal tissue of six individuals with Crohn’s disease as test samples, and five without Crohn’s as control samples. Past studies have shown that Crohn’s disease patients have higher levels of E. coli in their mucosa. The objective of this study was to see whether plant fibres and polysorbate-80 influenced the way E. coli moves into a cell, and whether these substances affected the development or course of Crohn’s disease.

The researchers found that the soluble plant fibres contained in broccoli and plantains reduced the translocation of E. coli across the cells, and that polysorbate-80 had the opposite effect: it increased the E. coli movement into the cells. This means that the consumption of these plant fibres may help protect individuals with Crohn’s disease from relapsing because they reduce the effect of bacterial infiltration into the cell. This also suggests that the increased use of food additives, such as polysorbate-80, could be contributing to the increase in the prevalence of Crohn’s disease.

Although more investigation is essential to confirm this very small study, the researchers believe that this discovery may lead to novel therapeutic approaches, and could help explain some of the environmental factors of Crohn’s disease, such as why it is more common in countries where processed food products are replacing whole plant foods in typical modern diets.


First published in the Inside Tract® newsletter issue 178 – 2011
1. Media Release. Non-radiologic modality benefits Crohn’s disease patients. 2011-03-18.
2. Health Canada. Occupational Exposure to Radiation. Available at: http://www.hc-sc.gc.ca/hl-vs/iyh-vsv/environ/expos-eng.php. Accessed 2011-06-11.
3. Radiologyinfo.org Radiation Exposure in X-ray and CT Examinations Available at: http://www.radiologyinfo.org/en/safety/index.cfm?pg=sfty_xray&bhcp=1. Accessed 2011-06-11.
4. Eisenburg MJ et al. Cancer risk related to low-dose ionizing radiation from cardiac imaging in patients after acute myocardial infarction. CMAJ. 2011;183(4):430-6.
5. Colombel JF et al. Infliximab, azathioprine, or combination therapy for Crohn’s disease. N Engl J Med. 2010;362(15):1383-95.
6. Roberts CL et al. Translocation of Crohn’s disease Escherichia coli across M-cells: contrasting effects of soluble plant fibres and emulsifiers. Gut. 2010;59(10):1331-1339.
7. Wise Geek. What is Polysorbate 80? Available at: http://www.wisegeek.com/what-is-polysorbate-80.htm. Accessed 2011-01-15.