There are a number of possible reasons for the association of celiac disease and neuropathy:
- A nutritional deficiency due to malabsorption. Deficiency of some vitamins (especially B12, B6 and E), and metals (especially copper) are well known to cause a peripheral neuropathy.
- Patients who have one autoimmune disease are predisposed to another autoimmune disorder more than the general population. Neuropathy could be a manifestation of another concomitant autoimmune disease in patients with celiac disease. For example, antibodies to some of the components of the peripheral nerves (i.e. gangliosides) are found in some celiac disease patients with neuropathy.
- It has been suggested that some of the antigens targeted in celiac disease (i.e. gliadin and tissue transglutaminase) have structural similarities to some of the proteins expressed in the nervous system. Therefore, it has been speculated that the autoimmunity in celiac disease could target intestinal cells and nervous system simultaneously. Other diseases of the nervous system have been reported in patients with celiac disease. As a matter of fact, lack of coordination (ataxia) is suggested to complicate gluten sensitivity with or without celiac disease. The majority of patients with ataxia associated with celiac disease also have a neuropathy.