Negative Celiac Test but Burning Feet? The Gluten–Neuropathy Link Doctors Miss

Yes, gluten can injure your nerves even when the celiac test is negative. Celiac screening looks for tTG-2 antibodies, which mark an attack on the gut. Gluten neuropathy targets the nerves instead. TG6 antibodies plus HLA-DQ2/DQ8 typing show what the standard panel misses.

You did the responsible thing. You mentioned your burning feet. Someone ordered a celiac panel, it came back negative, and gluten was crossed off the list. But for a large number of people with gluten-related nerve damage, that negative result is exactly where the diagnosis goes wrong. The celiac test answers a different question than the one your nerves are asking. This article explains why standard celiac screening misses gluten neuropathy, and what testing actually finds it.

Why does a celiac test miss gluten neuropathy?

Celiac disease is defined by an immune attack on the small intestine. Its screening tools are built to detect that. Mainly they look for antibodies to tissue transglutaminase-2 (tTG-2), the form of the enzyme concentrated in the gut. A gut biopsy showing damage to the villi confirms it.

Gluten-related neurological disease is a different form of gluten sensitivity. The immune response targets the nervous system, and the gut may be fully spared. So a patient can have a spotless celiac panel and a normal gut biopsy while making the antibodies that injure their nerves. The test isn’t broken. It is simply looking in the wrong place.

What does gluten attack in the nerves?

As covered in the companion article on the gluten–neuropathy link, the mechanism is molecular mimicry, a case of mistaken identity. Two targets matter most for a nerve-focused workup.

Transglutaminase-6 (TG6). This form of the enzyme is found in nerve tissue. Antibodies against it, described by Dr. Marios Hadjivassiliou’s group, mark the nerve form of gluten sensitivity. TG6 antibodies can be present when the gut-focused tTG-2 antibodies are absent. That is exactly why a celiac screen can miss nerve disease.

Anti-myelin and related antibodies. The immune response can also target parts of the myelin sheath that insulates nerves. That adds to the sensory neuropathy. When the cerebellum is involved, it adds to the ataxia (loss of balance and coordination) seen in gluten-related nerve disease.

What does an HLA-DQ2 or HLA-DQ8 gene test tell you?

Gluten sensitivity has strong genetic roots. The great majority of people who react to gluten, in either the celiac or the nerve form, carry one of two immune-system genetic markers: HLA-DQ2 or HLA-DQ8. Testing for these types tells you something different from antibody testing. A negative HLA-DQ2/DQ8 result makes gluten-driven disease very unlikely and can in effect rule it out. A positive result shows you are prone to it, though not everyone who is prone develops disease. That makes HLA typing a useful gatekeeper test in a workup for unexplained neuropathy.

How is gluten neuropathy tested?

Take someone with an unexplained sensory neuropathy, especially with any balance trouble. A fuller workup than a routine celiac screen includes HLA-DQ2/DQ8 genetic typing. It includes a wider gluten-related antibody panel (with TG6 where available, alongside the usual celiac antibodies). And it includes an exam for the sensory pattern that hits the longest nerves first, and for any signs from the cerebellum. The aim is to catch the nerve form that the standard screen is not built to see.

An important practical catch: antibody testing means the most while gluten is still in the diet. If a patient has already gone gluten-free, antibody levels may fall and give falsely reassuring results. Plan around this with a clinician before testing.

Can gluten neuropathy improve on a gluten-free diet?

Tracking down a gluten link is worth it because, unlike many neuropathy causes, it can be fully removed. The trigger is in the diet. When gluten-related nerve disease is confirmed and strict elimination starts early, symptoms can hold steady and sometimes improve. The tragedy of the missed diagnosis is that the person keeps eating the trigger for years. They blame their worsening nerve damage on bad luck or aging, when a change on the plate could have changed the course.

This is one driver among several

Gluten sensitivity is one possible cause checked within a broader root-cause search that also weighs metabolic, toxic, and mechanical causes. Several causes often exist together. So ruling gluten in or out is part of building the full picture, not a hunt for a single culprit.

Frequently asked questions

Key takeaways

• Standard celiac tests detect gut disease, not the nerve form of gluten sensitivity.
• Transglutaminase-6 (TG6) antibodies mark the nerve attack. They can be present with a negative celiac panel.
• HLA-DQ2/DQ8 typing is a useful gatekeeper. A negative result largely rules gluten out.
• Test while still eating gluten, since cutting it first can make antibody results falsely negative.
• Confirmed gluten neuropathy is uniquely treatable, because the trigger is removable.

This article is educational and is not a substitute for evaluation, diagnosis, or treatment by a physician. Individual results vary. Do not make major dietary or medication changes without consulting your physician. Take the free Nerve Damage Score or call (314) 886-5739 or text (314) 886-5902.

References

1. Hadjivassiliou M, et al. Transglutaminase-6 antibodies in the diagnosis of gluten ataxia. Neurology. 2013;80:1740–1745.
2. Hadjivassiliou M, Sanders DS, Grünewald RA, et al. Gluten sensitivity: from gut to brain. Lancet Neurol. 2010;9:318–330.
3. Hadjivassiliou M, et al. Gluten-related neurological dysfunction and HLA associations.
4. Volta U, et al. Serological tests in gluten-related disorders. Cell Mol Immunol / review.