[Insulin autoantibodies (IAA) in sera of individuals with negative values in IAA radioimmunoassay].

Insulin autoantibidy(IAA) is one of the most important markers for detection of population at risk to develop into Type I diabetes. In screening the subjects and following up their conditions, the authors re-examined some sera with IAA radioimmnoassasy by using different concentrations of unlabeled insulin. The results of these subjects were compared with those of normal controls and IAA positive diabetics. It was confirmed that there was actually a large amount of IAA in the sera of individuals with negative values in standard IAA radioimmunoassay. Only in this group, the levels of IAA varied with increased amount of unlabeled insulin (P < 0.01). Should similar events be confronted, it is advisable to increase the amount of unlabeled insulin in IAA radioimmunoassay on purpose to avoid missed diagnosis.