How are Crohn’s disease and ulcerative colitis similar? What sets them apart?
Crohn’s disease and ulcerative colitis (colitis) are inflammatory bowel diseases characterized by an autoimmune response that damages the mucosa, or inner lining, of your intestine. In ulcerative colitis, inflammation is limited to the colon and rectum, while Crohn’s disease can involve any portion of the gastrointestinal tract, from mouth to anus. The inflammation caused by Crohn’s often penetrates through the intestinal wall, leading to fistulas, perforation, and bowel obstruction. In contrast, the inflammation in colitis is typically confined to the innermost layer of your intestine. Both diseases affect organs other than the intestine, such as skin, joints, eyes, and blood vessels. These “extra-intestinal” manifestations are more likely to occur in people whose inflammatory bowel disease involves the colon, rather than just the small intestine. Nutrient malabsorption is more likely in Crohn’s disease due to involvement of the small intestine. Rectal bleeding is uncommon in Crohn’s disease, but is always present in colitis. Many of the same medications can be used to treat both diseases, although some immune-modulating agents that work for Crohn’s aren’t particularly useful for colitis. While removal of the colon and rectum will often cure colitis, surgery is avoided whenever possible in Crohn’s patients as it can aggravate their condition.
If I plan to become pregnant anytime in the future, is the treatment safe to take while pregnant, and are there other risks in pregnancy? What about for breastfeeding?
In the past, women with inflammatory bowel disease (IBD) were advised to avoid pregnancy, and women with active disease are still counseled to delay conception. However, if your disease is in remission, it’s possible to conceive, carry your infant to term, and have a normal delivery. Many medications used to treat inflammatory bowel disease (sulfasalazine, mesalamine, metronidazole, and corticosteroids) are Pregnancy Category B drugs, meaning they’re generally safe for developing fetuses. Other drugs that are classified as Pregnancy Category C or D (infliximab, azathioprine, and 6-mercaptopurine, for example) have been safely used during pregnancy as well. The only drugs that are absolutely contraindicated for pregnant women with inflammatory bowel disease are methotrexate and thalidomide. According to a March 2012 review in Alimentary Pharmacology and Therapeutics, drugs used to treat IBD are generally safe for breastfed infants, except for cyclosporine.
Will pregnancy increase my risks for onset of new autoimmune conditions that commonly occur with Crohn’s?
While the risk of acquiring a new autoimmune disease during pregnancy doesn’t seem to be heightened in women with inflammatory bowel disease, pregnancy does appear to increase a woman’s risk for developing other connective tissue disorders (lupus, autoimmune thyroid disease, rheumatoid arthritis, etc.) following delivery. This risk is highest in the first year following pregnancy and appears to be mediated through a process called microchimerism, which involves the trans-placental transfer of fetal cells to the maternal circulation. These fetal cells apparently persist in the mother’s tissues for years, and they are believed to play a role in triggering autoimmune responses that generate connective tissue diseases. Women with pre-existing autoimmune diseases, such as inflammatory bowel disease, might be more susceptible to the immune consequences of microchimerism.
Questions for your doctor
- Will my inflammatory bowel disease reduce my chances for conceiving?
- Is my current treatment plan safe for a developing infant?
- If I’m taking a medicine that’s not safe during pregnancy, how long before conception should I change drugs to a) ensure I’ll remain in remission throughout pregnancy and b) avoid any drug-related complications for my developing infant?
- Once I’m pregnant, what other specialists should be involved in my care to give me the best chance for a good outcome?
FM Habal, VW Huang. Review article: a decision-making algorithm for the management of pregnancy in the inflammatory bowel disease patient. Aliment Pharmacol Ther. 2012;35(5):501-515
AS Khashan, et al. Pregnancy and the risk of autoimmune disease. PLoS One. 2011;6(5):e19658
About the Author
Steve Christensen, MD – “Doom” to his close friends – was trained at the University of Utah School of Medicine. Since his premature retirement from medicine in 2003, Dr. Christensen has expanded his knowledge of alternative medicine: he is a certified herbalist; he has dabbled at the edges of Ayurvedism, shared ideas with Chinese physicians, rubbed shoulders with Native American healers and contemplated the healing powers of channeled energy.