Should stored serum of patients previously tested for celiac disease serology be retested for transglutaminase antibodies?
INTRODUCTION: Tissue transglutaminase (tTG) antibodies are currently recognized as a highly sensitive indicator of celiac disease (CD). Although a high concordance rate between tTG antibodies and anti-endomysial antibodies (EMA) has been reported up to a third of known CD patients are positive for only one of these antibodies. AIM: To determine whether in laboratories in which serum samples previously examined for CD serology markers had not been discarded, these samples should be tested for tTG antibodies. METHODS: Fifty-eight stored (frozen at -70) serum samples of patients previously found to be EMA-negative but positive for one or more of the non-EMA markers: antigliadin antibodies (AGA)-IgA, AGA-IgG, antireticulin antibodies, were tested for anti-tTG antibodies (IMMCO Diagnostics). In patients found to be tTG positive, medical charts were reviewed and patients or their physicians contacted. RESULTS: Twelve of fifty-eight (20.7%) samples were found to be anti-tTG positive. These in