What is Inflammatory Bowel Disease?
Inflammatory bowel disease (IBD) is marked by recurring episodes of inflammation in the digestive tract due to an unusual immune response to the bacteria in our guts. There are two types of IBD, each classified by where they occur and how deeply the inflammation affects the layers of the bowel wall.
The first type, Ulcerative colitis (UC), involves widespread inflammation of the lining of the large intestine. Typically, UC starts in the rectum and can gradually extend its reach into the first part of the large intestine (sigmoid), or further beyond, or sometimes can affect the entire large intestine up to a point called cecum.
The second type, Crohn’s disease (CD), causes ulcers that can affect any part of the digestive tract, though most often the problem area is the last part of the small intestine and the colon. UC and CD can range from mild to severe and are categorized based on the area they affect in the digestive tract. CD is also defined by its distinct forms such as purely inflammatory, causing narrowing of the bowel, or with complications like fistula or abscess.
Apart from affecting the digestive tract, both types of IBD have impacts on other parts of the body. While each disease usually has distinguishing features, about 10% of people show symptoms of both types, making it difficult to initially distinguish between UC and CD.
Both these conditions are linked to genetic factors, neither has a cure, and both carry a significant risk of debilitating complications. Importally, both these disorders also increase the risk of colon cancer.
What Causes Inflammatory Bowel Disease?
Inflammatory bowel disease (IBD) happens when people, who are already genetically predisposed, have an incorrect immune response to the bacteria in their digestive tract.
Currently, we don’t know the exact cause of IBD. There are many theories, but none are proven to be common in all patients. One thing that stands out is that people who use tobacco often get a specific type of IBD – Crohn’s disease. Interestingly, it seems like smoking might lower the chances of getting another type of IBD – ulcerative colitis. The influence of diet on IBD is still uncertain.
There’s a gene called CARD15 that has been connected to IBD. But since this gene can have different forms, we can’t determine which part of the digestive track will be affected. The role of genes in ulcerative colitis is not as apparent as in Crohn’s disease.
Risk Factors and Frequency for Inflammatory Bowel Disease
Inflammatory Bowel Disease (IBD), including conditions like ulcerative colitis and Crohn’s disease, commonly appear in North America. The rates of occurrence change depending on the specific condition. In North America, per 100,000 people in a year, between 2.2 and 19.2 may get ulcerative colitis, and for every 200,000 people, between 3.1 and 20.2 may get Crohn’s Disease. There are more people with these conditions in North America and Europe than in Asia or Africa.
- The incidence of Ulcerative Colitis ranges from 2.2 to 19.2 cases per 100,000 person-years, and 3.1 to 20.2 cases per 200,000 person-years for Crohn’s disease in North America.
- The prevalence of adult ulcerative colitis is 238 per 100,000 people, and 201 per 100,000 people for Crohn’s disease in the United States.
- IBD is more common in North America and Europe than in Asia or Africa.
- Most people with IBD are aged between 15 to 30 years old, though up to 25% of patients could develop IBD in their teenage years.
- There is also a second common age group, where 10% to 15% of people develop IBD after the age of 60.
- Crohn’s disease is slightly more common in females, but ulcerative colitis affects both genders equally.
- IBD is commonly seen in developed countries and colder climates.
Signs and Symptoms of Inflammatory Bowel Disease
Ulcerative colitis is a digestive disorder that often manifests as bloody diarrhea, sometimes with mucus. People with this disease often report abdominal pain and a sensation of incomplete evacuation, termed “tenesmus”. If the examination shows tenderness on the left side of the abdomen or signs of a seriously inflamed abdomen, it could point to a potentially harmful condition called toxic megacolon.
Crohn’s disease, another digestive disorder, can present various symptoms based on where inflammation, blockage, or abnormal tunnels (fistulae) form in the digestive tract. Right lower belly pain, weight loss, and non-bloody diarrhea can hint at a flare-up of Crohn’s disease. The presence of fistulas might bring on symptoms such as fecaluria (feces in urine), pneumaturia (air bubbles in urine), and rectovaginal fistulas (abnormal connections between the rectum and vagina). A lump in the right lower belly could indicate an abscess, a swollen area within tissue that contains a buildup of pus.
In kids, both of these diseases can impact normal development leading to delayed growth and sexual maturation.
The World Gastroenterology Organization describes the following common symptoms for inflammatory bowel diseases, the group that includes both ailments:
- Diarrhea which might contain blood or mucus, and could happen at night or lead to stool incontinence.
- In few cases of ulcerative colitis, when the inflammation is only in the rectum, it might present as constipation.
- Abdominal pain, urgent need to evacuate, and tenesmus.
- Pain in the lower right part of the belly in Crohn’s disease, whereas pain in the lower left part in ulcerative colitis.
- Nausea and vomiting, which are more common in Crohn’s disease.
During a physical exam, the doctor might notice:
- Speedy heartbeat, anxiety, fever, and dehydration.
- Paleness due to anemia.
- In severe cases, toxic megacolon could manifest as intense pain, fever, bloated belly, chills, and lethargy.
- In Crohn’s disease, anal fistulas, abscesses, or even rectal prolapse might be detected.
- Presence of hidden blood in a rectal exam.
- In kids, the only noticeable sign might be delayed growth.
Testing for Inflammatory Bowel Disease
Diagnosing Inflammatory Bowel Disease (IBD) involves numerous steps. This includes a review of clinical symptoms, specific laboratory tests, imaging scans, and tissue samples collected through a procedure called an endoscopy. Blood tests are often done to check for signs of inflammation or infection, as well as anemia. Also, doctors might look for specific indicators in the blood like elevated white blood cell count and platelets.
Special inflammatory markers like the erythrocyte sedimentation rate (ESR) and high-sensitivity C-reactive protein (hs-CRP) are often checked too, as they can suggest inflammation in the body. In some cases, doctors might need to rule out parasitic infections like giardia or Strongyloides, or even tuberculosis.
Doctors may also request a complete blood count, which helps identify anemia, abnormal white blood cell count, and albumin levels. Fecal calprotectin levels can also be tested; they often increase when inflammation in the intestine is present. Specific antibodies may be checked to assist in diagnosing Crohn’s disease specifically. Stool studies may also be conducted to rule out parasitic organisms which may mimic IBD symptoms.
As part of the imaging studies, a simple abdominal X-ray can be done to check for signs of free air, bowel obstruction, or toxic megacolon. Barium studies, which involve swallowing a special liquid that shows up on an x-ray, can highlight specific features that indicate conditions like ulcerative colitis or Crohn’s disease.
Other advanced imaging techniques like ultrasound (US), computed tomography (CT), and magnetic resonance imaging (MRI) are also used in diagnosing IBD or checking for any complications. These high-tech scans can provide useful information about different parts of the bowel, including the presence of fistulas (abnormal connections between the bowel and other organs), blockages, or strictures (narrowed parts of the bowel).
Finally, a definitive diagnosis of IBD often requires an endoscopy procedure, during which a small tube with a camera and light is used to visualize and take samples from the bowel. An endoscopy may involve viewing either the upper or lower part of the digestive tract or sometimes both.
Treatment Options for Inflammatory Bowel Disease
The aim of inflammatory bowel disease (IBD) treatment, which includes ulcerative colitis (UC) and Crohn’s disease (CD), is to alleviate symptoms. Treatment strategies are grouped based on the intensity of the disease – mild, moderate, or severe. Often, medications meant for severe cases are now introduced earlier in the treatment process.
For UC, the chosen treatments largely depend on how wide-reaching the disease is and if there are additional effects beyond the digestive system. Medicines called aminosalicylate agents, like mesalamine, are often used when the disease is mild to moderate and only affects the rectum. Mesalamine is usually administered rectally and can be combined with orally taken drugs to ease or control symptoms. If these drugs do not work for patients with moderate diseases, oral steroidal drugs or therapies derived from immune cells can be alternatives. Unfortunately, a total colon removal surgery might be needed for completely uncontrollable diseases in one-quarter of all UC patients.
The procedure known as Proctocolectomy with ileal pouch-anal anastomosis (IPAA) is the most preferred for elective cases. During illness flare-ups, corticosteroid therapy is typically used. If the flare-ups occur more than once or twice annually, the use of anti-TNF agents or other medicines that suppress the immune system are recommended.
Treatment for CD depends on which part of the digestive tract is affected and if there are complications such as fistulae (abnormal connections between organs), strictures (narrowing of passages), and any effects beyond the digestive system. Mostly, mesalamine is used for mild ileocecal (the part of the intestine connecting the small and large intestines) disease. This can be supplemented with a steroidal drug called oral budesonide which limits side-effects by being greatly metabolized in its first pass through the liver. For wider-reaching diseases, systemic steroid therapy with prednisone is necessary.
The aim is to withdraw these steroidal drugs in six weeks. If the steroids cannot be withdrawn, an immunomodulating agent like 6-mercaptopurine, azathioprine, or low-dose methotrexate is added. For moderate to severe disease, an anti-tumor necrosis factor (anti-TNF) should be started. Prior to starting this biological treatment, it’s important to test patients for latent tuberculosis. Patients with severe fistulizing disease might need surgical treatment.
Also, it’s key to measure bone density in patients who receive steroids; osteoporosis has a significant impact on these patients’ health. If steroid use for more than three months is anticipated, calcium supplements and bone-strengthening medications should be introduced.
There’s a step-by-step approach followed in managing IBD:
– The first step is to try aminosalicylates.
– If the patient doesn’t respond to that, the next step is to include steroidal drugs, which tend to significantly lessen inflammation.
– The third step is introducing immune-modifying agents like anti-TNF if the steroidal treatment does not work, if long-term steroidal usage is required, or if withdrawal of steroids leads to a recurrence of symptoms.
Recently, specialists have tended to favor more a top-down approach for patients with severe or high-risk disease. This involves introducing higher step medications like anti-TNF drugs early and then reducing their dosage once the patient responds. This method appears to improve outcomes and prevent problems in high-risk or severe patients.
The final step, step four, includes testing drugs that are still in the trial phase, specific to either UC or CD. Examples include thalidomide and interleukin-11 for Crohn’s disease, and butyrate enema, nicotine patch, and heparin for ulcerative colitis. Please remember that these experimental drugs come with several potential side effects.
What else can Inflammatory Bowel Disease be?
When people suddenly start having diarrhea, the doctor first needs to rule out infection as the cause. This could be from parasites, certain bacteria like Escherichia coli 0157:H7, or an organism called Clostridioides difficile. There are also other conditions such as microscopic, lymphocytic, and collagenous colitis that might be causing diarrhea.
People with stomach pain must also be evaluated for different conditions. This can include appendicitis (an inflammation of a part of the gut called the appendix), irritable bowel syndrome (a condition causing stomach pain and bowel problems), celiac disease (an intolerance to a protein called gluten found in wheat), and functional abdominal pain (pain without an identified cause). The doctor will consider all these possibilities to find the most accurate diagnosis.
What to expect with Inflammatory Bowel Disease
The future health of someone with ulcerative colitis (UC) or Crohn’s disease (CD) often depends on how much of their body is affected and how well they respond to treatment. Stool markers, such as lactoferrin and calprotectin, are helpful tools to figure out if CD recurrence is likely to happen after surgery. They can also possibly help predict future disease outbreaks. Unfortunately, patients with these diseases generally have a higher risk of death compared to others, due to the initial disease, infections, or respiratory illnesses. However, heart disease is not a contributing factor to their higher mortality rate.
People with these conditions often suffer from mental health issues and have a lower quality of life. As such, it’s very important for patients with long-term UC to regularly check for dysplasia, a type of pre-cancerous condition. If someone has had the disease for 30 years or more, there is a risk as high as 30% that they might develop colorectal cancer. Furthermore, another complication of ulcerative colitis, a condition known as primary sclerosing cholangitis, can cause liver failure.
Possible Complications When Diagnosed with Inflammatory Bowel Disease
Inflammatory bowel disease (IBD) can lead to a variety of complications. These adverse effects can be divided into two categories: those that affect the intestines directly and those that occur outside the intestines.
Here are the complications found in the intestines:
- Uncontrolled bleeding, also known as hemorrhage
- Narrowing of the intestines, or strictures
- Rupture or perforation of the colon
- Anal fistulas, which are abnormal connections between the anus and other parts of the body
- Pelvic or perirectal abscesses, or pockets of pus
- Toxic megacolon, a potentially life-threatening condition where the colon rapidly expands
- Cholangiocarcinoma and colon cancer, both types of digestive system cancers
The complications that occur outside the intestines include:
- Osteoporosis, or weak and brittle bones
- Deep vein thrombosis, a serious condition where a blood clot forms in a deep vein, usually in the leg
- Anemia, or low red blood cell counts
- Gallstones, or small, hard deposits that form in the gallbladder
- Primary sclerosing cholangitis, a liver disease that can lead to liver failure
- Aphthous ulcers, or mouth ulcers
- Arthritis, or swelling and tenderness of one or more of your joints
- Iritis, or inflammation of the iris
- Pyoderma gangrenosum, a rare, painful skin condition
Preventing Inflammatory Bowel Disease
People who suffer from inflammatory bowel disease (IBD), a long-term and chronic condition, are generally young. Increasing their understanding of the disease is crucial as it helps them better manage their condition and follow their treatment plan. It’s important for IBD patients to maintain regular check-ups throughout their lives to manage their disease effectively. Despite popular belief, there’s no specific diet or supplement proven to slow down or prevent the symptoms of this disease.
