Is the Simtomax, Point-of-care (PoCT) Test For Celiac Disease Worthwhile?

Last year, Sigma Pharmaceuticals (Sigma), launched the new Simtomax celiac disease in-pharmacy screening test in Australia. The test can quickly tell patients whether they could potentially have celiac disease or not. The new test, involves a small finger prick blood sample, which is then tested on site at the pharmacy and gives you results in 10 minutes. This new test for celiac disease is available exclusively at Amcal, Amcal Max and Guardian pharmacies in Australia. These pharmacies are all owned by Sigma. Simtomax is available in some other countries as well.

Research has found that celiac disease affects as many as 1 in 60 women and 1 in 80 men in Australia, but is often left undiagnosed due to non-specific symptoms and inadequate testing. Traditional testing involves a clinical history, blood tests sent off to be tested in a laboratory and a biopsy of the small intestine. It is surprising to think that up to 90% of Australian’s who suffer from celiac disease don’t even know they have it.  And that is a dangerous for their long term health.

Celiac disease is an autoimmune disease triggered by gluten in the diet. Left undiagnosed or untreated, people with celiac disease are at an increased risk of osteoporosis, pregnancy complications, cancer and other autoimmune conditions.

The new screening test is simple, non-invasive, readily accessible, and only takes about 10 minutes. Anyone can be screened in pharmacy for celiac disease without having to consult a doctor first. However if the testing is positive, the patient is advised to consult their doctor for follow up testing.

However specialists in the field have raised concerns about point-of-care (PoC) finger-prick testing for celiac disease, currently offered in 440 Australian pharmacies and currently being rolled out to doctors this year. Prior to testing a pre-screening questionnaire assesses symptoms and suitability.

In a letter to the MJA, gastroenterologists, Dr Evan Newnham and Dr Jason Tye-Din said the accuracy of the PoC test Simtomax was less than laboratory based tests, and interpreting the colored line that appears on the device can be difficult. he reports that false positive results occurred in about 10% of PoC celiac tests, with false negatives reported in about 15 to 20%.  Other reports I have read  indicate that the inaccuracy of the test may be even higher than this.

However, James Nevile, a spokesperson for Sigma, which owns Amcal and Guardian pharmacies, said the AU $45 test was not meant to be a diagnostic tool. “What we’re trying to do is drive patients toward seeing a GP. It’s certainly not about any removal of the role of the GP,” he said. And I believe that is good thing. 

However Dr Tye-Din, chair of Celiac Australia’s medical advisory committee and a researcher at the Walter and Eliza Hall Institute of Medical Research, Melbourne, said he was concerned about self-diagnosis, which “could potentially mean a lot of people are starting gluten-free diets unnecessarily”. This is because it is reported that the new Simptomax celiac disease in-pharmacy screening test is only 49% accurate when it comes to positive results, which means more than half the people the test says have celiac disease actually don't.

Despite this, I believe that PoC tests are a good indicator for someone with chronic bloating or tiredness especially those people who avoid going to the GP.  Anyone who had a positive test or persistent symptoms must be encouraged to see their GP for further testing.  Being encouraged to see a doctor is a good thing.

The fact that there is so many people with undiagnosed celiac disease is certainly a worry because these people can end up with life threatening illness, so anything that gets them to be celiac disease aware must be good in my view.  We need to reach out to these undiagnosed cases and get them to seek medical attention. A positive test will no doubt lead them on to seek medical treatment where an accurate diagnosis can be made.  But what about the false negative results?

  

Dr Sue Hookey, a Melbourne-based GP, said her greatest concern was with false negative results.
“People think they can keep eating gluten and this could have a real impact on their quality of life.”  

The validity of the test has not been proven as being reliable for a general population screening tool.  In fact, as of late last year, researchers at Royal Liverpool Hospital in the UK, when using the test on 112 patients at high risk of celiac disease,  recommended that it should not be used as screening test because it had low sensitivity (too many false negatives).

I also think that this is a huge risk because celiac disease is a great “mimicker” and could be missed if people who had a negative PoC test were not referred for further investigation as well. The symptoms of celiac disease are usually quite obvious. The symptoms of celiac disease could include any of the following:

 

·         Diarrhoea
·         Joint or muscle pain
·         Bloating/Abdominal pain
·         Heavy painful periods
·         Constipation
·          Headaches
·         Chronic mouth ulcers
·         Acne
·         Unexpected weight loss
·         Bulky stool
·         Itchy skin rash
·         Brittle nails

But if you are asymptomatic and do not have the obvious symptoms, celiac disease could be overlooked until it is too late to do anything about it? Some of the signs to look for and consider in asymptomatic celiac disease are:

• Pre-existing type 1 diabetes (10% also have celiac disease)
• A direct relative (parent, sibling) with type 1 diabetes or celiac disease
• Low iron
• Unstable glucose levels in diabetics
•  Growth issues in children

So to answer the question is the simtomax point-of-care (PoCT) test for celiac disease worthwhile? I believe the answer is yes because it raises people's awareness of celiac disease. However results should be interpreted with caution and any positive results followed up with proper testing from a doctor prior to the person starting on a gluten free diet.

A person with a negative result and obvious symptoms of celiac disease should also be encouraged to consult a doctor. The symptoms may or may not be due to celiac disease. It is important to get a proper diagnosis for the root cause of the problem and more sinister illness like bowel cancer and IBS - Irritable Bowel syndrome etc. need to be investigated as well as celiac disease. Only a doctor can do that.

If you are diagnosed with celiac disease the only treatment is to go on a gluten free diet for the rest of your life. If you need help transforming your home into a gluten free zone , read my book, "What is Gluten Free? it will give you all the guidelines you need to start your gluten free journey.