[Evaluation of preserved insulin secretion in children and adolescents with type 1 diabetes].
BACKGROUND
The pathogenesis of type 1 diabetes is connected with immune-mediated beta-cell destruction leading to insulin deficiency. The majority of patients will become completely incapable of insulin secretion within a few years, however, some individuals will have persistent beta-cell function years after the diagnosis of diabetes. Despite clinical symptoms of insulin deficiency, residual beta-cell secretion can modify the clinical course and can be an independent factor influencing the delay of development of chronic diabetic complications. The aim of the study was to compare a 10-year clinical course in children with type 1 diabetes with and without preserved beta-cell secretion.


METHODS
72 children and adolescents with diabetes lasting for minimum 10 years and available biological material to c-peptide evaluation (3-4 years and 10 years from the onset of diabetes) were chosen from 768 children with type 1 diabetes. We assessed fasting c-peptide and recruited 23 out of 72 patients whose concentration of c-peptide was below or over 0.23 ng/ml at all time points (this cut point derives from the definition of preserved beta-cell function according to DCCT). Afterwards we divided children into two subgroups: A (n=13) - without insulin secretion and B (n=10) - with preserved beta-cell function during 10 years of observation. We assessed markers of beta-cell autoimmunity (ICA, GADA, IA2, IAA) in the examined groups. Insulin requirement and concentration of glycated hemoglobin (assessed as the year mean from four measurements in each year) were compared between group A and B.


RESULTS
The age at onset of diabetes in children from both examined groups was similar. All children from group B and 12/13 from group A were positive for at least one type of the screened autoantibodies. There was no difference in insulin requirement between the groups (p=0.6). The level of glycated hemoglobin was significantly lower in group B during a 10-year observational period (p=0.04).


CONCLUSIONS
Repeated measures of c-peptide can enable us to define two groups of patients with immune-mediated diabetes with different levels of disease and metabolic control.
Wegner
Olga
O
Klinika Pediatrii, Onkologii, Hematologiii, I Katedra Pediatrii Uniwersytetu Medycznego w Łodzi. owegner@poczta
Wyka
Krystyna
K
Fendler
Wojciech
W
Zmysłowska
Agnieszka
A
Młynarski
Wojciech
W
D000293:Adolescent; D001323:Autoantibodies / Q000032:analysis; D002096:C-Peptide / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D003922:Diabetes Mellitus, Type 1 / Q000276:immunology / Q000378:metabolism*; D005260:Female; D006801:Humans; D007328:Insulin / Q000378:metabolism*; D000078790:Insulin Secretion; D050417:Insulin-Secreting Cells / Q000276:immunology / Q000378:metabolism; D008297:Male
D001323:Autoantibodies; D002096:C-Peptide; D007328:Insulin