How is Crohn's disease diagnosed?
The diagnosis of Crohn's disease is suspected in patients with fever, abdominal pain and tenderness, diarrhea with or without bleeding, and anal diseases. Laboratory blood tests may show elevated white cell counts and sedimentation rates, both of which suggest infection or inflammation. Other blood tests may show low red blood cell counts (anemia), low blood proteins, and low body minerals, reflecting loss of these elements due to chronic diarrhea. A thorough history, physical exam and series of tests are required to diagnose Crohn's disease. Blood tests are necessary to look for low blood counts
(anemia) that might indicate bleeding into the intestines. A high white blood cell count might indicate intestinal inflammation. Other blood tests help with understanding a patient's nutritional status and overall health. After basic blood work is completed, the physician will run a series of tests to determine which parts of the digestive system are involved and the extent or degree of the involvement. This allows the physician to counsel the patient on a prognosis and to customize a treatment plan.
Sigmoidoscopy is a procedure that allows the doctor to directly examine the lining of the rectum and lower portion of the colon. It is usually performed with 60-centimeter flexible fiberoptic scope, but a shorter, rigid scope may be used. The procedure can be performed in a doctor's office or health clinic. The exam takes 5-20 minutes, and no sedation is needed. The fiber-optic tube, which contains a light source and a camera lens, is inserted into the anus and advanced up through the rectum and into the descending (sigmoid) colon. The doctor looks for irregularities in the lining of the colon. For most people, sigmoidoscopy is mildly uncomfortable. However, for individuals who are in the midst of a flare-up of inflammatory bowel disease, the procedure can be painful. Sigmoidoscopy is more useful for diagnosing ulcerative colitis than Crohn's disease. The test can, however, rule out Crohn's disease if a view of the sigmoid colon shows clear signs of ulcerative colitis.
Colonoscopy is similar to sigmoidoscopy, but the much longer colonoscope allows the doctor to thoroughly examine the entire colon (advancing from the rectum to the terminal ileum, the end of the small intestine). Modern colonoscopes use microchip-driven electronic imaging and screen projection; these have replaced older fiber-optic scopes. Colonoscopy takes about 30 minutes and is generally performed with the patient under what is called "conscious anesthesia." Conscious anesthesia, which can be described as a semi-conscious state, is achieved through a combination of a sedative and pain medication. Because sedation is used, colonoscopy must be performed in a hospital or an endoscopy clinic that has been approved and licensed by the state and can provide appropriate emergency care in case of anesthesia-related complications. Because most people remain drowsy for some hours after the procedure, it is usually necessary to take the day off from work to undergo a colonoscopy. A small set of forceps inside the colonoscope allows the doctor to remove small tissue samples for biopsy (to check for cellular changes that may indicate cancer or precancerous conditions) or to remove polyps.
In this procedure, a barium sulfate suspension is injected into the colon through a tube inserted in the rectum and a series of radiographs (x-rays) is taken. Often, air is also injected to help inflate the colon. The barium suspension acts like a dye for the radiographs. Without the "dye," plain film radiographs would not show the soft tissue of the bowel clearly. The lining of the bowel must be seen clearly if the proper diagnosis is to be made. The barium enema is considered the "gold standard" in distinguishing among Crohn's disease of the colon (Crohn's colitis), Crohn's disease of the ileum (ileitis), and ulcerative colitis. Enough barium usually goes beyond the colon into the terminal ileum to reveal if that area is diseased, and the barium allows the radiologist and the gastroenterologist to see if the disease is continuous, or skips from patches of diseased tissue to healthy tissue and back again.
If Crohn's disease is limited to the small intestine, a colonoscopy will not detect the disease. However, Crohn's disease can almost always be detected on x-rays after barium is swallowed. X-rays taken after barium is given by enema can reveal the characteristic appearance of Crohn's disease in the large intestine. Computed tomography (CT) can show changes that are helpful in distinguishing between Crohn's disease and ulcerative colitis and is the best way to identify complications that occur outside the walls of the intestinal tract, such as abscesses or fistulas.
More information on inflammatory bowel diseases (ulcerative colitis, Crohn's disease)
What are the inflammatory bowel diseases? - Inflammatory bowel disease (IBD) is a chronic disorder that causes an inflamed and swollen digestive tract or intestinal wall.
What causes inflammatory bowel diseases? - The cause of inflammatory bowel disease is not known. Chronic inflammation present in the intestines of persons with both forms of IBD damages the bowel.
What are the symptoms of inflammatory bowel diseases? - Symptoms of inflammatory bowel diseases can include chronic diarrhea, abdominal cramps or pain, fever, and blood or mucus in the stool.
How is inflammatory bowel disease diagnosed? - To make a diagnosis of inflammatory bowel disease, a doctor must first exclude other possible causes of inflammation.
What're the treatments for inflammatory bowel disease? - Inflammatory bowel disease is treated with medication, exercise, and sometimes, surgery. Treatments for IBD are directed against the inflammation in the bowel.
What're the medications for inflammatory bowel disease? - Medications for inflammatory bowel disease include sulfasalazine, corticosteroids, immunosuppressives, and nonsteroidal anti-inflammatory drugs (NSAIDs).
What is Crohn's disease? - Crohn's Disease is a chronic illness that causes irritation in the digestive tract. Crohn's disease occurs in the last portion of intestine (ileum).
What types of Crohn's disease are there? - There are five subtypes of Crohn's disease, distinguished by the gastrointestinal area in which the disease occurs.
What causes Crohn's disease? - The cause of Crohn's disease is unknown. There is now evidence of a genetic link as Crohn's frequently shows up in a family group.
What are the symptoms of Crohn's disease? - The symptoms of Crohn's disease include abdominal pain, diarrhea, fever, loss of appetite and weight loss.
What are the complications of Crohn's disease? - Common complications of Crohn's disease include the development of an intestinal obstruction, pus-filled pockets of infection, and abnormal connecting channels.
How is Crohn's disease diagnosed? - The diagnosis of Crohn's disease is suspected in patients with fever, abdominal pain and tenderness, diarrhea with or without bleeding, and anal diseases.
What're the treatments for Crohn's disease? - Treatment for Crohn's disease is mainly symptomatic. Medications are very effective at improving the symptoms of Crohn's disease.
What medications cure Crohn's disease? - Medications for Crohn's disease sulfasalazine, Asacol, Pentasa and Dipentum. Mesalamine is useful both to achieve and maintain remission.
What's the surgery for Crohn's disease treatment? - Surgery to remove part of the intestine can help Crohn's disease but cannot cure it. The most used operation in Crohn disease is removing the diseased part of the intestine.
What Crohn's disease diet is suggested? - Diet may have to be restricted based on symptoms or complications of Crohn's disease. No particular food has ever been implicated in causing Crohn's disease.
Crohn's disease in children - Crohn's disease is most often diagnosed in young adulthood. Children facing Crohn's disease have significant self-image issues to deal with.
Crohn's disease and pregnancy women - Women with Crohn's disease who are considering having children can be comforted to know that the vast majority of such pregnancies will result in normal children.
What is ulcerative colitis? - Ulcerative colitis is an inflammatory disease of the bowel, that usually affects the distal end of the large intestine and rectum.
What types of ulcerative colitis are there? - Doctors categorize ulcerative colitis by the amount of colon involved. Variability of symptoms reflects differences in the extent of disease and the intensity of inflammation.
What causes ulcerative colitis? - The cause of ulcerative colitis is not known, but heredity and an overactive immune response in the intestine may be contributing factors.
What are the symptoms of ulcerative colitis? - The symptoms vary according to the extent of the disease. The most common symptoms of ulcerative colitis are abdominal pain and bloody diarrhea.
What are the complications of ulcerative colitis? - Bleeding, the most common complication of ulcerative colitis, often causes iron deficiency anemia.
How is ulcerative colitis diagnosed? - Diagnosis of ulcerative colitis is suspected based on the symptoms that a patient is experiencing. The most important method of diagnosis is endoscopy.
What are the treatments for ulcerative colitis? - Treatment of ulcerative colitis depends on the location and severity of a patient's disease, the presence of complications.
What ulcerative colitis medications are available? - Medications for ulcerative colitis include 5-ASA Compounds, anticholinergic drugs, steroids, and immunosuppressive drugs.
What surgery treats ulcerative colitis? - Surgery for ulcerative colitis involves removal of the entire colon, regardless of whether all or only a portion of the colon is diseased.
Collagenous colitis and lymphocytic colitis - Collagenous colitis and lymphocytic colitis are chronic diseases in which certain kinds of white blood cells infiltrate the lining of the large intestine.