Relationship of islet cell and islet cell surface antibodies to the presentation and early course of IDDM in childhood.

Islet cell (ICA) and islet cell surface (ICSA) antibodies were measured in 30 children (aged 6-17.7 years) with newly diagnosed insulin-dependent diabetes mellitus (IDDM) to determine the relationship of antibody positivity/negativity to a variety of factors both at presentation (e.g., age, severity of onset, residual insulin secretion, insulin autoantibodies) and during the first year thereafter (HbA1c, insulin antibody binding, residual insulin secretion). At diagnosis, 10 of 30 were ICA (+) and 13 ICSA (+): no differences were found between ICA (+) and (-) subjects at onset; however ICSA (+) children had a lower bicarbonate concentration than those (-) for ICSA (P less than 0.01). During the first year after diagnosis the only significant finding was that in ICA (+) patients insulin dose (units/kg) was lower at both 6 and 12 months (mean +/- SD 0.55 +/- 0.14 and 0.67 +/- 0.12 U/kg, respectively) than ICA (-)'s (0.70 +/- 0.22 and 0.96 +/- 0.38, respectively, both P less than 0.05). Those children positive for both ICA and ICSA did not differ in any way at onset or during the subsequent 12 months from those negative for both antibodies. These results suggest that, except for minor differences, the presentation and course during the first year after diagnosis of IDDM do not differ in those children positive or negative for either or both ICA and ICSA.