Changing patterns of coeliac serology requests

Accurate serological tests have revolutionized the diagnosis of coeliac disease.

To quantify the volume of coeliac serology requests at a district hospital over a decade, identify their origin, assess positivity rates and subsequent duodenal biopsy and histological confirmation rates.

Details of patients in whom coeliac serology was requested from 1997 to 2006 were obtained from laboratory databases. The origins of request were categorized into gastroenterology, general practice, paediatrics and other specialities. Duplicate requests were excluded.

A total of 9976 serological tests were requested. Testing increased from 302 in 1997, to 1826 in 2006. In all, 66% of requests were in females. Tests in children accounted for 14-25% of each year's total. General practitioner requests increased from 3.3% in 1997 to 52% in 2006. The proportion of positive serological results fell from 5.7% in 1997 to 2.6% in 2006. Duodenal biopsies were performed in approximately 85% of seropositive patients in earlier years and approximately 75% of seropositive patients in later years. Most nonbiopsied seropositive patients had serology requested by general practitioners. Biopsies confirmed coeliac disease in 91% of seropositive patients.

Increasingly, coeliac serological testing is requested by general practitioners. Twice as many females are tested. Increasing test numbers but diminishing positivity rates suggest testing is requested at lower symptom thresholds. Positive serological results are often not confirmed histologically.