ASCA Test - IgG

Anti-Saccharomyces Cerevisiae Antibodies (ASCA) are immune proteins present in people with inflammatory bowel disease. This test detects the amount of ASCA present in the bloodstream.

Inflammatory Bowel Diseases (IBD) is a collective group of chronic disorders that may occur in the body due to an autoimmune reaction characterised by damaged and swollen tissues in the lining of the intestinal tract. The symptoms of IBD vary depending on the severity of a case. Sometimes, people with IBD might experience flare-ups or even remission of the symptoms with time.

 The most common types of IBD diseases are Crohn Disease (CD) and Ulcerative Colitis (UC). CD is known to affect parts of the intestinal tract, anywhere from the mouth to the anus. However, it is mostly found in the small intestine of the colon. UC is primarily found in the colon.

The diagnosis of CD and UC is made by examining the biopsy samples collected from the intestines through endoscopy. However, it may be difficult to diagnose one of the two only with the biopsy samples, as both CD and UC develop in the colon region and distinguishing between them can get complex.

In such a situation, the ASCA IgG profile test helps doctors analyse better, as people who have ASCA in their blood will have CD. It is not that ASCA is not found in the bloodstream of people with UC, but the quantities are much lower than a CD.

The ASCA IgG Test helps gauge the severity of the disease and determine if you will need surgery. Your doctor will ask you to take the test if you have:

• Abdominal pain and cramps
• Diarrhoea
• Rectal bleeding
• Fever or unexplained weakness

Bowel related diseases are common in India. UC is generally found in the northern region of India, while CD is commonly found in the southern region of India. A lot of research is happening in the country, but still, the figures are unclear as many people avoid taking the tests. Also, it is seen that IBD generally occurs among people between the ages of 18 to 25 in India.

Intermittent Diarrhoea, Crohn Disease, Ulcerative Colitis, IBD

The ASCA IgG Test measures the amount of IgG antibodies in the blood.

Some chronic diseases that can happen because of IBD are:

• Chronic inflammation of the gastrointestinal tract
• Bone, joint, skin or any other organ-related symptoms
• Delayed development and growth retardation in children
• Anorexia

It is prescribed to people who have the following complaints:

• Diarrhoea
• Abdominal pain and cramps
• Fever
• Rectal bleeding
• Unexplained weakness or fatigue
• Increased urgency to have a bowel movement or defecate
• Mucous rectal discharge
• Bloating
• Constipation
• Nausea/Vomiting

The ASCA IgG Test is applicable to males and females, both adults and children.

The doctors prescribe ASCA IgG Test. It is not a test that is included in your full body check-up. If the doctor suspects IBD, he will ask you to take the ASCA IgG Test. If the results of the test confirm a diagnosis, appropriate medication should be taken under the guidance of your doctor.

The doctors may ask you to repeat the ASCA IgG Test after 15 or 20 days. This will help the doctor to check if the treatment is working on the patient effectively or a change of medication is needed.

Before the Test

Your physician will not mandate any specific pre-test requirements for the ASCA IgG Test. However, should you be required to undergo this test concurrently with another that necessitates fasting, you may be advised to abstain from foods. For further details, please consult with your doctor.

During The Test

The ASCA IgG Test involves the extraction of a blood sample from a vein in your arm:

• The area where the needle will be inserted will be disinfected with antiseptic.
• To enhance the visibility of the veins, a tourniquet will be applied around your arm.
• A needle will be inserted into a vein to collect the blood, which will cause a brief pinch.
• The collected blood will be transferred to a vial/small test tube, and a label bearing your personal information will be attached.

After the Test

Following the collection of the blood sample:

• A bandage will be applied to control any bleeding at the puncture site.
• It is common to experience bruising there. Should you feel lightheaded (a rare but possible side effect), rest for a few minutes until the sensation subsides.
• If there is persistent bleeding, severe pain, or the development of rashes at the puncture site, please contact your doctor for further guidance.

The ASCA IgG Test measures the amount of ASCA antibodies present in the blood. Based on that, the doctor is able to understand the severity of the IBD disease and differentiate between Crohn Disease and Ulcerative Colitis. This test helps the doctor to decide if the patient needs surgery.

The results of the ASCA IgG Test are expressed as positive or negative. However, there are reference ranges given as well.

The ASCA IgG Test results are positive or negative. However, there is a reference range that determines this.

• The Equivocal range for ASCA IgG is between 20 to 24 units.
•  If the result is less than 20 units, the ASCA IgG Test result is expressed as negative.
• If the result is more than 25 units, the ASCA IgG Test result is expressed as positive.

The normal values and reference ranges of the test may vary from lab to lab. Please refer to the ranges mentioned in the report and consult a doctor to understand the interpretation of lab reports.

Your doctor might tell you to take the pANCA Test with ASCA IgG Test as the results are often interpreted in conjunction.

• If ASCA is positive and pANCA is negative, then the patient has CD.
• If ASCA is negative and pANCA is positive, then the patient has UC.

However, the negative test results for ASCA and pANCA do not rule out the possibility of IBD. There are cases where patients with negative results still have IBD, UC or CD. The doctor will ask you to take some other tests if he still suspects IBD.

Also, the presence of multiple antibodies in the blood like ASCA IgG, ASCA IgA, anti-Omp C and anti-CBir1 indicates the likelihood of more aggressive diseases. However, the negative results do not rule out the possibility of aggressive disease. Thus, it is very important to stay under a physician who will not rule out any possibilities and give you the necessary treatment.