Crohn’s disease and ulcerative colitis are collectively known as inflammatory bowel disease (IBD). Both conditions affect the bowel, but in slightly different ways. Crohn’s disease causes inflammation of the full thickness of the bowel wall, in any part of the digestive tract from the mouth to the anus. Ulcerative colitis is inflammation of the inner lining of the large bowel (colon and rectum).
Crohn’s disease is a type of inflammatory bowel disease (IBD). It causes inflammation of your digestive tract, which can lead to abdominal pain, severe diarrhea, fatigue, weight loss and malnutrition.
More research about Crohn’s disease is necessary. Researchers aren’t sure how it begins, who is most likely to develop it, or how to best manage it. Despite major treatment advances in the last 3 decades, no cure is available yet.
Crohn’s disease most commonly occurs in the small intestine and the colon. It can affect any part of your gastrointestinal (GI) tract, from the mouth to the anus. It can involve some parts of the GI tract and skip other parts.
Inflammation caused by Crohn’s disease can involve different areas of the digestive tract in different people. This inflammation often spreads into the deeper layers of the bowel.
Crohn’s disease is a chronic, or long-term, condition that causes inflammation of the digestive tract. Crohn’s disease can be painful, debilitating, and sometimes life threatening.
Crohn’s disease can be both painful and debilitating, and sometimes may lead to life-threatening complications.
Understanding Crohn’s Disease
Crohn’s Disease is a condition that causes inflammation of the digestive system (also known as the gastrointestinal tract or gut). Inflammation is the body’s reaction to injury or irritation, and can cause redness, swelling and pain.
Crohn’s Disease is one of the two main forms of Inflammatory Bowel Disease (IBD). The other main form of IBD is a condition known as Ulcerative Colitis. Crohn’s is sometimes described as a chronic condition. This means that it is ongoing and life-long, although you may have periods of good health (remission) as well as times when symptoms are more active (relapses or flare-ups).
In many people the disease runs a benign course with few flare-ups, while other people may have more severe disease. Crohn’s Disease is not infectious.
What Are the Main Symptoms of Crohn’s Disease?
Common symptoms of Crohn’s disease include abdominal pain, diarrhea, and weight loss. Less common symptoms include
- poor appetite,
- night sweats,
- rectal pain, and
- occasionally rectal bleeding.
The symptoms of Crohn’s disease are dependent on the location, the extent, and the severity of the inflammation. The different subtypes of Crohn’s disease and their symptoms are:
- Crohn’s colitis is inflammation that is confined to the colon. Abdominal pain and bloody diarrhea are the common symptoms. Anal fistulae and perirectal abscesses also can occur.
- Crohn’s enteritis refers to inflammation confined to the small intestine (the second part, called the jejunum or the third part, called the ileum). Involvement of the ileum alone is referred to as Crohn’s ileitis. Abdominal pain and diarrhea are the common symptoms. Obstruction of the small intestine also can occur.
- Crohn’s terminal ileitis is inflammation that affects only the very end of the small intestine (terminal ileum), the part of the small intestine closest to the colon. Abdominal pain and diarrhea are the common symptoms. Small intestinal obstruction also can occur.
- Crohn’s enterocolitis and ileocolitis are terms to describe inflammation that involve both the small intestine and the colon. Bloody diarrhea and abdominal pain are the common symptoms. Small intestinal obstruction also can occur.
- Crohn’s terminal ileitis and ileocolitis are the most common types of Crohn’s disease. (Ulcerative colitis frequently involves only the rectum or rectum and sigmoid colon at the distal end of the colon. These are called ulcerative proctitis and procto-sigmoiditis, respectively.)
Up to one-third of patients with Crohn’s disease may have one or more of these conditions, symptoms, and signs that involve the anal area affected.
- Swelling of the tissue of the anal sphincter, the muscle at the end of the colon that controls defecation.
- Development of ulcers and fissures (long ulcers) within the anal sphincter. These ulcers and fissures can cause bleeding and pain with defecation.
- Development of anal fistulae (abnormal tunnels) between the anus or rectum and the skin surrounding the anus). Mucous and pus may drain from the openings of the fistulae on the skin.
- Development of perirectal abscesses (collections of pus in the anal and rectal area). Peri-rectal abscesses can cause fever, pain and tenderness around the anus.
What Are the Different Types of Crohn’s Disease?
Crohn’s is often categorised according to which part or parts of the gut are most affected. Sometimes it can affect more than one part of the gut. The main types are as follows:
• Terminal ileal and ileocaecal
Crohn’s in the ileum (the last part of the small intestine) may be called ileal or sometimes ‘terminal ileal’ Crohn’s – because it is affecting the terminus or end of the ileum. If it also affects the beginning of the large bowel it is known as ileocaecal Crohn’s. This is one of the most common forms of Crohn’s Disease.
Typical symptoms are pain in the lower right side of the abdomen, especially after eating, diarrhoea and weight loss. Any bleeding is unlikely to be visible in stools, but stools may appear black and blood tests may show that you are anaemic.
• Small bowel
This type of Crohn’s is also referred to as ileitis or jejunoileitis, depending on the part of the small bowel affected. Abdominal pain and diarrhoea are also typical symptoms of Crohn’s in the small bowel, along with nutrient deficiencies. Again, the diarrhoea is unlikely to be blood-stained, but you may still have anaemia, and also weight loss. The small bowel is commonly affected in children and young people.
Crohn’s Disease in the colon (large intestine or large bowel) is often called Crohn’s Colitis. This is also a common form of Crohn’s Disease, but is not the same as Ulcerative Colitis. The main symptom tends to be diarrhoea, with blood and mucus.
Because of the inflammation, the colon cannot hold as much waste as normal and you may have very frequent bowel movements, especially if your rectum is inflamed. You may also have urgency to pass stools, and tenesmus (feeling the need to pass a stool although the rectum is empty).
Crohn’s in the upper gut – the oesophagus, stomach or duodenum – is much less common, but may occur on its own or alongside Crohn’s in other parts of the digestive system. Key symptoms include indigestion- like pain, nausea with or without vomiting, loss of appetite, and weight loss and anaemia.
Crohn’s in the area around the anus (back passage) can occur on its own or at the same time as inflammation in other parts of the body. It is quite common, and some people notice perianal symptoms before they develop intestinal symptoms. It causes a number of symptoms, such as:
• Fissures – these are tears or splits in the lining of the anal canal (back passage), which can cause pain and bleeding, especially during bowel movements.
• Skin tags – small fleshy growths around the anus.
• Haemorrhoids (piles) – swollen blood vessels in or around the anus and rectum.
• Abscesses – collections of pus that can become swollen and painful. They are often found in the area around the anus and can cause a fever or lead to a fistula.
• Fistulas – these are narrow tunnels or passageways between the gut and the skin or another organ. See Living with a Fistula.
• Oral Crohn’s
Crohn’s can occasionally affect the mouth.True oral Crohn’s is often referred to as ‘orofacial granulomatosis’ and is more likely to affect children, although it is rare. It typically causes swollen lips and mouth fissures. Some people with Crohn’s may develop mouth ulcers during flare-ups. This can sometimes be due to nutritional deficiencies such as vitamin B12, folate and iron.
What Causes Crohn’s Disease?
It isn’t clear what causes Crohn’s disease. However, the following factors may influence your chances of developing it:
- your immune system
- your genes
- your environment
Up to 20 percent of people with Crohn’s disease also have a parent, child, or sibling with the disease, according to the CCFA.
According to a 2012 study, certain factors can affect the severity of your symptoms. These include:
- whether you smoke
- your age
- whether or not the rectum is involved
- length of time you’ve had the disease
People with Crohn’s are also more likely to develop intestinal infections from bacteria, viruses, parasites, and fungi. This can affect the severity of symptoms and create complications.
Crohn’s disease and its treatments can also affect the immune system, making these types of infections worse.
Yeast infections are common in Crohn’s and can affect both the lungs and the intestinal tract. It’s important that these infections are diagnosed and properly treated with antifungal medications to prevent further complications.
Crohn’s Disease Diagnosis
Doctors use many tests to distinguish Crohn’s disease from other conditions like ulcerative colitis.
First, your doctor will review your medical history and talk about your symptoms. They might want to order some lab tests, like:
- Bloodtests, including blood counts
- Stool samples to rule out infections as the cause of diarrhea
- Imaging tests:
- MRI. This shows your doctor a clear picture of the inside of your body without using radiation.
- CT scan. This test uses X-rays to make detailed images of your internal organs.
- Endoscopy. Your doctor might send you to a specialist called a gastroenterologist to get one of these:
- Balloon-assisted enteroscopy. This test uses balloons that inflate and deflate to pull a flexible tube called an endoscope through your small intestine. A tiny camera on one end gives a view of the inside of your guts.
- Capsule endoscopy. You’ll swallow a tiny, pill-sized camera to give the doctor a closer look at your small intestine.
- Upper endoscopy. The doctor does this to see your esophagus, stomach, and duodenum.
- Colonoscopy or sigmoidoscopy. These give the doctor a clear picture of your intestines and let them take a tissue sample to study.
How Is Crohn’s Disease Managed or Treated?
Treatment for Crohn’s disease varies depending on what’s causing your symptoms and how severe they are for you. In children, the goal in treatment is to induce remission (the time between symptom flare-ups), maintain remission and manage any complications of Crohn’s disease over time.
Your healthcare provider may recommend one or more of these treatments for Crohn’s disease:
- Antibiotics: Antibiotics can prevent or treat infections. Severe infections can lead to abscesses (pockets of pus). Or they can cause fistulas (openings or tunnels that connect two organs that don’t normally connect).
- Antidiarrheal medication: Prescription medications like loperamide (Imodium A-D®) can stop severe diarrhea.
- Biologics: These medications include monoclonal antibodies to suppress the immune response.
- Bowel rest: To give your intestines a chance to heal, your provider may recommend going without food or drink for several days or longer. To get the nutrition you need, you may receive intravenous (parenteral) nutrition. Only drink a prescribed liquid or have a feeding tube during this time.
- Corticosteroids: Cortisone, prednisone and other corticosteroids ease inflammation brought on by autoimmune disease.
- Immunomodulators: These drugs calm inflammation by suppressing an overactive immune system. They include azathioprine and cyclosporine.
- Surgery: Surgery won’t cure Crohn’s disease, but it can treat complications. You may need surgery to correct intestinal perforations (holes), blockages or bleeding.