Test Details & Preparation

• ASCA test is done to help distinguish between Crohn’s disease (CD) and ulcerative colitis (UC), the two most common types of inflammatory bowel disease (IBD) as an adjunct to other IBD testing.


• ASCA test is performed when you have symptoms such as persistent or intermittent diarrhoea and abdominal pain that your doctor suspects may be due to an IBD when your healthcare practitioner wants to distinguish between CD and UC.


• A blood sample drawn from a vein in your arm for an ASCA test.


• No preparation is needed for an ASCA test.


• A positive ASCA result is not diagnostic of CD, UC, or of an IBD, but it does make it more likely that a person with symptoms has an IBD.


• Results of ASCA testing are often interpreted in conjunction with the results of pANCA testing.


• If ASCA is positive and pANCA is negative, then it is likely that the person has CD.


• If ASCA is negative and pANCA is positive, then it is likely that the person has UC.


• A negative result for ASCA and pANCA does necessarily rule out IBD. A person who is negative may still have CD, UC, or another IBD.


• The presence of multiple antibodies (ASCA, anti-CBir1, anti-Omp C) may indicate the likelihood of a more aggressive disease, but negative results do not rule out aggressive disease.