Multiple studies have shown an association between IgA deficiency and coeliac disease. Although the pathogenesis is unclear, it has been proposed that a lack of secretory IgA and Peyer's patch malfunction allow for increased free gluten peptides in the submucosa. 
Patients with long-standing or refractory abdominal symptoms should be screened for coeliac disease.  Patients may present with chronic or intermittent diarrhoea.
Patients with long-standing or refractory abdominal symptoms should be screened for coeliac disease. 
Iron deficiency anaemia is the most common clinical presentation in adults. Folate (and rarely vitamin B12) deficiency may lead to a macrocytic anaemia. 
Characterised by intensely pruritic papulovesicular lesions that occur symmetrically over the extensor surfaces of the arms and legs, as well as on the buttocks, trunk, neck, and scalp.  Biopsy-proven dermatitis herpetiformis almost universally occurs in association with coeliac disease.
Family history of coeliac disease or other autoimmune disorders.
History of bone pain or previous fracture, due to vitamin D deficiency and hypocalcaemia.
Associated with iron deficiency anaemia. 
Likely to be multi-factorial, primarily due to malabsorption but also to changes in motility, metabolism, and appetite. 
In children, faltering growth and delayed puberty are indications for testing for coeliac disease. 
Clinicians caring for patients with type 1 diabetes mellitus should be aware of the association with coeliac disease and consider testing if there are any digestive symptoms or laboratory changes to suggest coeliac disease.  Some clinicians suggest screening asymptomatic individuals with type 1 diabetes mellitus for coeliac disease every 5 years but the clinical benefits of this approach are not well established. 
Clinicians caring for patients with autoimmune thyroid disease should be aware of the association with coeliac disease and consider testing if symptoms occur.   Unexplained increasing need for levothyroxine or treatment-refractory hypothyroidism should also lead to coeliac disease testing.   Correspondingly, patients with coeliac disease should be screened for thyroid disease. 
Caused by various nutritional deficiencies, although the particular deficiency is not always evident.  May be recurrent.
The exact aetiology is unclear but is felt to be due to nutritionally derived abnormalities in mineralisation.
Vitamin K deficiency may lead to a coagulopathy.
The aetiology of neurological dysfunction may be the result of either vitamin deficiencies (B12, E, or D; folate or pyridoxine) or autoimmune activity against neural antigens. 
Cerebellar ataxia is one of the more common neurological symptoms. 
Multiple studies have shown an increased risk in family members, probably secondary to genetic factors. 
Multiple studies have shown an association between immunoglobulin A (IgA) deficiency and coeliac disease. Although the pathogenesis is unclear, it has been proposed that a lack of secretory IgA and Peyer patch malfunction allow for increased free gluten peptides in the submucosa. 
The association between type 1 diabetes mellitus and coeliac disease is well known. It is probably based on genetic factors favouring autoimmunity, including the presence of human leukocyte antigen (HLA)-DQ2 and HLA-DQ8 and single nucleotide polymorphisms shared by both diseases.   Leaky gut, with tight junction defects leading to increased passage of luminal peptides into the submucosa, resulting in immune activation, is also hypothesised, as well as enhanced basal expression of inflammatory markers.  
Some studies have shown an increased prevalence of coeliac disease in patients with Sjogren's syndrome. 
A few studies have shown an increased prevalence of coeliac disease in patients with Crohn's disease and, to a lesser extent, ulcerative colitis. 
Studies have shown an increased prevalence of coeliac auto-antibodies in patients with primary biliary cirrhosis and other liver diseases, but false positives appear higher in these populations. 
Use of this content is subject to our disclaimer