Serological screening suggests that adult coeliac disease is underdiagnosed in the UK and increases the incidence by up to 12%.

Because coeliac disease often presents atypically it is underdiagnosed. It is suggested that the detection rate may be increased by 12% if serology is used to identify cases of occult enteropathy. All adults noted incidentally to be R1 anti-reticulin antibody (ARA) positive in the course of routine autoantibody testing of 6532 sera over one year were followed. None of the eight patients with seropositive serum was suspected of having coeliac disease. All eight had high titres of IgA anti-gliadin and IgA anti-endomysial antibodies, neither of which is detected in a routine autoantibody test, in addition to IgA R1-ARA. On clinical review coeliac disease was considered probable in only one patient, but because of the strong serological evidence of gluten sensitivity, jejunal biopsy was advised in all eight. Seven agreed and all had villous atrophy and crypt hyperplasia in keeping with coeliac disease. Six of the seven presented initially with vague symptoms such as tiredness or arthralgia. These symptoms disappeared after several weeks of gluten withdrawal. Forty two sera showing reticulin staining patterns other than R1 were used as controls. Low titre IgA anti-gliadin was noted in two of 42 but none had IgA anti-endomysial antibody. These 42 cases were not recommended for biopsy. During our study 58 other new adult cases of coeliac disease were diagnosed, primarily on clinical rather than serological grounds, at the four hospitals that request autoantibody studies. Occult coeliac disease detected serologically thus increased the overall incidence of coeliac disease by 12% from 58 to 65 cases. R1-ARA, even in the absence of the expected symptoms and signs of coeliac disease, is an indication for jejunal biopsy and is a reliable indicator of occult coeliac disease.