Causes and Diagnoses

Causes and Diagnoses of Ulcerative Colitis

The exact cause of ulcerative colitis is unknown, but it is an autoimmune disease, meaning the immune system attacks healthy tissue. Research has shown that in ulcerative colitis, the immune system might be reacting to a bacteria or a virus, but it doesn’t stop fighting long after the bacteria or virus is conquered.  

Other research has shown that several factors are involved:

  • Genetics: A number of people with ulcerative colitis have a family member with the same condition.
  • Ethnicity: Ulcerative colitis is most common among Caucasians of European descent, including Ashkenazi Jews. 
  • Stress: While not a cause, stress may aggravate ulcerative colitis symptoms.
  • Diet: Certain foods may trigger symptoms in some individuals. 

Diagnosing ulcerative colitis

There are a number of tests for diagnosing ulcerative colitis and identifying the severity of the disease. They include:

  • Blood test: Lab tests can identify infection, antibodies, anemia, and vitamin and mineral deficiencies. 
  • Fecal blood test: This test shows if there is blood in your stool, indicating inflammation.  
  • X-ray: Traditional X-ray images can indicate the severity of the inflammation and scarring, and show if there are any blockages. 
  • CT scan: A computed tomography (CT) scan combines X-ray and computer technology to produce detailed cross-sectional images of your intestines.
  • Colonoscopy: An endoscope (long, flexible tube) with a lighted camera goes through colon, allowing your physician to view the lining. A sigmoidoscopy uses the same technology but examines only the sigmoid colon (the lower third). 
  • Endoscopic ultrasound (EUS): While you are under mild sedation, an endoscope (flexible tube) with an ultrasound probe is inserted in your colon to create more precise images than may be available using external ultrasound. 
  • Magnetic resonance imaging (MRI): This test uses a magnetic field and radio waves to create pictures of your digestive tract. 

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