An association between celiac disease (CD), connective tissue diseases (CTD), inflammatory bowel disease (IBD), and primary biliary cirrhosis (PBC) has been reported.
However, a high rate of false positives in autoantibody testing has been noted.
In this study, doctors from Italy investigated 400 patients with CTD, 170 with IBD, 48 with PBC, and 120 healthy subjects for CD. They analyzed IgA and IgG tTG antibodies using human recombinant tTG immunoenzymatic assay.
|The highest rate of false positives was in PBC patients.|
|Digestive Diseases and Sciences|
Patients and controls with positive findings were further tested for antiendomysial antibodies by indirect immunofluorescence and HLA typing.
Those found positive by either of these tests underwent duodenal biopsy to confirm a possible diagnosis of CD.
The doctors found that 2% of patients were positive for IgA or IgG tTG antibodies.
They determined that only 0.8% of controls had a low level positive reaction for IgA anti-tTG.
Among the 13 subjects returning positive tests only 2 had CD.
The team found that the highest rate of false positives was in PBC patients.
Dr Bizzaro's team concluded, "Serological screening testing for CD is not recommended in CTD patients or in subjects affected with IBD or PBC, unless there is a relevant clinical suspicion of CD".