Could a blood test diagnose celiac disease without the need to trigger symptoms?
- Celiac disease has to do with an abnormal immune response of the
body to gluten.
- Experts are interested in the best ways to test for celiac disease.
- A recent study discovered that a blood test called WBAIL-2 could aid in diagnosing celiac disease and even contribute to biopsy-free diagnosis.
Celiac diseaseTrusted Source occurs
when someone’s immune system responds abnormally to gluten. Efforts to improve
celiac disease diagnosis are ongoing.
A study recently published in Gastroenterology evaluated the effectiveness of using a
blood test that measures the cytokineTrusted Source interleukin-2
to diagnose celiac disease.
The study’s results indicated that
the test to be highly effective for celiac disease diagnosis, even for people
following a gluten-free diet.
The test could offer another option
to help with celiac disease diagnosis — importantly, one that would not require
triggering symptoms to confirm the disease.
Is this blood test method effective at predicting celiac disease?
The authors of the current study note
that there is often a delay or lack of diagnosis when it comes to celiac
disease. Diagnosis usually involves people having to eat gluten and get
biopsies of the small intestine.
Celiac disease also has to do with
the response of a group of immune cells,
CD4+ gluten-specific T-cells. For this study, researchers wanted to determine
if the use of a blood test that measures interleukin-2 — a protein produced by
some T-cells — release could help to accurately diagnose celiac disease.
This research involved a total of 181
adult participants between 18 and 75 years old. Of these participants, 88 had
celiac disease, and others were controls. Among controls, 32 participants had a
non-celiac gluten sensitivity and were on a gluten-free diet. The rest were
healthy controls who did not have gluten sensitivity.
All participants provided blood
samples, and researchers collected data on medications and medical history.
A subset of participants, including
healthy controls, participants with non-celiac gluten sensitivity, and treated
celiac disease, went on a gluten-free diet for four weeks or more and then
consumed gluten for “a single-dose open-label gluten challenge.”
Some participants with treated celiac
disease also did an oral gluten challenge that lasted 3 days. If participants
underwent the oral gluten challenge, they used diaries to keep track of their
symptoms.
Researchers utilized a blood test
called a WBAIL-2 assay, which measures the release of interleukin-2 in vitro
after adding gluten peptides.
In general, the test was able to effectively confirm celiac disease, with
higher concentrations and fold change of interleukin-2 in participants who had
celiac disease. However, the results were less sensitive for participants with
a certain, less common genotype.
Analysis results also found that the
WBAIL-2 assay correlated with age and the number of years participants had been
following a gluten-free diet.
Novel test can diagnose gluten
sensitivity even in those on gluten-free diet
Next, researchers tested
participants’ serum levels of interleukin-2 after they did an oral gluten
challenge. The levels of interleukin-2 were higher for participants with celiac
disease following the oral gluten challenge.
Researchers also found these levels
“positively correlated with the WBAIL-2 results.” So, if the levels of
interleukin-2 were elevated on one test, they were also elevated on the other.
They also tested how the WBAIL-2
results related to the presence of gluten-specific T cells, which were higher
among participants with celiac disease. They did find that the presence of
these cells, as well as activated versions of these cells, correlated with the
WBAIL-2 test.
The researchers further found that
gluten-specific T cells, activated versions of these cells, and WBAIL-2
increased after participants underwent a gluten challenge. However, one
participant had lower gluten-specific CD4+ T cells and a lower WBAIL-2 test on
day six.
Researchers also looked at treated
celiac disease participants and how the tests related to their symptoms after
gluten exposure. When it came to gluten-specific T-cells, their frequency was
higher in participants who experienced vomiting. The measurement of serum interleukin-2
following the gluten tolerance test was also elevated, as was the WBAIL-2
level. The WBAIL-2 level was also increased greatly for one participant who did
not experience vomiting but did report severe tiredness.
Further analysis also suggested that activated
gluten-specific CD4+ T cells are the cells that lead to gluten-induced
production of interleukin-2.
The results suggest that the WBAIL-2 assay can help with celiac disease
diagnosis, even when people are already following a gluten-free diet.
Study limitations and continued research
There are some limitations to this
study. For one thing, it was performed out of one area, most participants were
female, and there were strict inclusion criteria, so it has a limited
generalizability.
It also had small sample sizes for
some subgroups, which means more research may be particularly necessary in
these subgroups. Since researchers did not test children or people taking
immunosuppressants, more research is needed to see how well this testing method
would work in these populations.
Researchers also acknowledge an
untested “reproducibility across laboratories.” More research is thus needed
before the WBAIL-2 assay can really be used in the clinical setting.
Further, the authors did not examine
the cost-effectiveness of the WBAIL-2 test and how well this would stack up
against current ways of diagnosing celiac disease.
Then, the test was not as accurate
for some participants with a specific genotype, which means it might not work
for everyone.
However, the number of participants
with this genotype was very small in this study, and it is possible that the
level of interleukin-2 response of some participants with this genotype was
just not able to be detected by the test.
Overall, more research is required
regarding this subtype of individuals and the use of this test.
Ian Storch, DO, an osteopathic physician specializing in
gastroenterology and internal medicine, and an American Osteopathic Association
member, who was not involved in this study, spoke to Medical News Today about
its findings.
Storch explained that:
“One limitation of this study is the
poor performance in the DQ8 genetic arm, which makes up 10% of celiac patients.
This will decrease the sensitivity and specificity for the control group or
require HLA typing before the assay is run.”
Researchers acknowledge that the
serum analysis of interleukin-2 following a gluten challenge does not always
line up with the results of the WBAIL-2 assay, which could have to do with the
assays’ differences.
Shilpa Mehra Dang, MD, double board-certified in
gastroenterology and internal medicine with Medical Offices of Manhattan and
contributor to LabFinder, who was similarly not involved in this research,
noted that “we need to look at bigger samples to really see its clinical
usefulness.”
In addition to larger studies,
research can also focus on more details regarding gluten-specific T cells.
Helping people who experience celiac disease
Celiac disease is a challenging
condition to manage, and accurate diagnosis is important. Researchers suggest
that examining WBAIL-2 and serum interleukin-2 after gluten consumption could
allow people with celiac disease to not have to get biopsies done to confirm
celiac diagnosis.
The authors of this study also
suggest that the WBAIL-2 assay could also become a first test among people
following a gluten-free diet and help with symptom severity prediction.
Storch said: “I do not think that
based on the data presented, removal of histology to confirm the diagnosis can
be suggested.”
Jeffrey D.
Davis, DO, CMD, an osteopathic physician specializing in Family
Medicine and Preventive Health and an American Osteopathic Association board
member, who was not involved in the study, noted the following to MNT:
“I see potential for a commercially
available rapid, simple, cost-effective laboratory test for physicians to use
to assist in the accurate diagnosis of celiac disease. This study shows that
especially in adults already on a gluten-free diet using this lab test versus
currently available tests would improve our diagnostic capabilities for Celiac
Disease. However, it would most likely be just another tool in our tool box to
aid in the diagnosis along with other current diagnostic methods.”
No comments:
Post a Comment