[Factors involved in ketoacidosis at the onset of type 1 diabetes in childhood].

BACKGROUND

In some patients the ketoacidosis at the onset of type 1 diabetes has been observed.

OBJECTIVE

The aim of this study was to investigate an effect of the clinical, genetic, immunological and metabolic parameters on the occurrence of ketoacidosis at the clinical onset of the disease.

METHODS

106 children with type 1 diabetes, aged 1.8-18.2 years (average 10.6), 40 female and 66 male, were studied. Diabetic ketoacidosis was defined as blood pH of less than 7.35 and severe acidosis as less than 7.2. Among the clinical features, age at onset of the disease and gender of patients were evaluated. Moreover, fasting C-peptide level, insulin requirement, HbA1c level, blood glucose level and body mass index normalized by age and sex were examined at the onset and 6, 12, 24 and 36 months after diagnosis. The HLA-DQA1 and DQB1 alleles and -23 HphI INS polymorphism and CTLA4 gene +49 polymorphism (PCR-RFLP) were studied and islet cell antibodies (ICA) as well as antibodies to glutamic acid decarboxylase (GADA) and thyrosine phosphatase antibodies (IA2A) were also determined.

RESULTS

The presence of diabetic ketoacidosis was observed in 55% and severe form in 9% of children. In the group of patients with ketoacidosis lower C-peptide level and lower c-peptide/glycaemia ratio than in children without ketoacidosis were observed (0.20+/-0.18 vs. 0.31+/-0.28 pmol/ml and 0.07+/-0.05 vs. 0.20+/-0.17, p<0.003, respectively). The patients with fasting C-peptide at the onset below normal range (<0.28 pmol/ml) were at high risk of ketoacidosis, OR (95%CI)=3.3 (1.3-8.2). The patients with ketoacidosis were characterized by higher exogenous insulin requirement than non-ketoacidosis individuals (1.2+/-0.6 vs. 0.8+/-0.5 j/kg/24h, p=0.004). Besides, in patients with severe ketoacidosis higher level of IA2A was found as compared to other patients (73.4+/-44.9 vs. 44.2+/-39.6; p=0.04). In this group more frequently 2 and/or 3 different autoantibodies were observed (90% vs. 79%), although, the difference was not significant.

CONCLUSIONS

The presence of diabetic ketoacidosis at clinical diagnosis of type 1 diabetes may be related to the residual b cell function, which is mainly determined by the intensity of immunological destruction.