Inflammatory bowel disease or IBD is the term for chronic inflammatory diseases of the intestine. There are two types of IBD: ulcerative colitis and Crohn’s disease.
What is Crohn’s Disease?
As mentioned above, Crohn’s Disease is a type of IBD that can cause inflammation anywhere along the digestive tract. Symptoms of IBD include abdominal pain, severe diarrhea, fatigue, weight loss and malnutrition. Inflammation typically occurs in the deep layers of bowel tissue.
What are the symptoms of Crohn’s Disease?
Common symptoms of Crohn’s Disease include:
- Severe diarrhea
- Fever
- Fatigue
- Abdominal pain
- Bloody stool
- Mouth sores
- Weight loss
- Reduced appetite
- Anal pain
- Anal drainage
Severe cases may result in:
- Inflammation of the skin, eyes and joins
- Inflammation of the liver or bile ducts
- Delayed growth
- Delayed sexual development
Crohn’s disease is typically experienced as short periods of inflammation or exacerbation of inflammation, interspersed between periods of remission or more healthy states. While initially the disease may not significantly affect the individual’s life, in up to 20% of patients, it may eventually lead to some form of disability.
What is the difference between Ulcerative Colitis and Crohn’s Disease?
While Crohn’s disease and Ulcerative Colitis share several symptoms, how and where they induce inflammation is very different. Shared symptoms of the diseases include:
- Abdominal pain
- Diarrhea
- Constipation
- An urge to have a bowel movement
- A feeling of incomplete bowel elimination
- Rectal bleeding
- Fever
- Reduced appetite
- Weight loss
- Fatigue
- Night sweats
- Abnormal menstrual cycle
However, these conditions differ in the tissues affected by the disease. Ulcerative Colitis occurs in the innermost lining of the lower intestine. Crohn’s disease on the other hand can occur in any tissues of the digestive tract, including the mouth and anus. It also can affect all layers of the tract, not just the innermost layer. In the case of Ulcerative Colitis, there is inflammation throughout the affected tissue. In Crohn’s disease however, tissue tends to be healthy between inflamed areas.
While these diseases share many symptoms, rectal bleeding is more likely to occur in Ulcerative Colitis than in Crohn’s disease. Because Crohn’s disease can affect several regions of the digestive symptom, several secondary conditions may occur, such as tears in the anal tissue, sores in the mouth, ulcers and infections. The response of these conditions to treatment is also different. Approximately, 90% of Ulcerative Colitis cases undergo remission following treatment. However, remission of Crohn’s disease is less common.
To definitively distinguish between the two conditions, there are several diagnostic tests that can be conducted such as:
- X-rays and contrast x-rays
- Computed tomography (CT) scans
- Magnetic resonance imaging (MRI)s
- Endoscopy
Blood tests are also being developed to help distinguish between the conditions.
EPIDEMIOLOGY
The first cases of CD were reported in Poland and Scotland in the early 1900s. This condition was later named Crohn’s disease in 1932. While it was primarily found in urban areas in Northern Europe and North America at first, by the 1960s, cases of the disease were identified in nearly every country in the world. In the United States, approximately 700,000 people are living with CD.
ETIOLOGY
It is unclear what causes Crohn’s disease, but there are several different conditions that have been associated with the disease. Because a clear cause has not been defined, CD is primarily managed by treating disease related symptoms. The two main conditions associated with CD are smoking and genetic risk factors. Crohn’s disease also has a genetic component. A study analyzing the gene expression of 15 participants with IBD found that nearly 163 different gene locations may be responsible for Crohn’s disease susceptibility. While most of these locations were also found in patients with Ulcerative Colitis, 30 were exclusive to CD. Many individuals with Crohn’s disease may develop other conditions that exacerbate their inflammation. For example, 1 in 4 people may also develop fistulae, which are sores that spread from the intestines into the surrounding tissue, like the anus. Perianal disease is another disease that may appear, which is a collection of anal abscesses. Other diseases that may arise are stricture, which are the narrowing of the intestines, dilatation, or perforation of the intestines. Other abnormalities that can arise include in the joints, eyes, liver and skin. These non-intestinal symptoms are rare, they typically occur in 6% of people with the disease. Cancer may also arise from this disease in more severe cases.
CD is typically diagnosed in teenagers and young adults. However, the condition can develop at any age. As much as 30% of Crohn’s disease cases occur in children. Crohn’s disease is primarily treated in children using EEN. However, if the child is not responsive, steroid therapy may also be used. Children commonly take prednisolone orally in moderate to severe cases. For more mild cases, budesonide may be taken, since it has fewer side effects. Children may also take treatments provided to adults such as TNF therapies and antibiotics. However, these are typically used to maintain remission. Like with adults, surgery is also a potential option for children with particularly severe cases.
