Islet autoantibody status in a multi-ethnic UK clinic cohort of children presenting with diabetes

• Published in: Archives of disease in childhood Vol. 100; no. 4; pp. 348 - 352
• Main Authors: Perchard, R, MacDonald, D, Say, J, Pitts, J, Pye, S, Allgrove, J, Banerjee, K, Amin, R
• Format: Journal Article
• Language: English
• Published: England BMJ Publishing Group Ltd 01-04-2015
• Subjects: Adolescent; Analysis; Analysis of Variance; Autoantibodies; Autoantibodies - metabolism; Child; Child, Preschool; Children; Diabetes in children; Diabetes Mellitus, Type 2 - ethnology; Diabetes Mellitus, Type 2 - immunology; Diagnosis; Enzyme-Linked Immunosorbent Assay; Female; Fluorescent Antibody Technique, Indirect; Health aspects; Humans; Infant; Infant, Newborn; Islands of Langerhans; Islets of Langerhans; Islets of Langerhans - immunology; Juvenile diabetes; Male; Phenotype; Prospective Studies; Risk factors; United Kingdom; United Kingdom > UK; England; Endocrinology; Race and Health
• ISSN: 0003-9888; 1468-2044
• DOI: 10.1136/archdischild-2014-306542

Objective We prospectively determined islet autoantibody status in children presenting with diabetes to a single UK region in relation to ethnicity. Design 316 (68.0% non-white) children presenting with diabetes between 2006 and 2013 were tested centrally for islet cell autoantibodies (ICA) and glutamic acid decarboxylase autoantibodies (GAD-65) at diagnosis, and if negative for both, tested for insulin autoantibodies (IAA). The assay used to measure GAD-65 autoantibodies changed from an in-house to a standardised ELISA method during the study. Results Even with use of the standardised ELISA method, 25.8% of children assigned a diagnosis of type 1 diabetes still tested negative for all three autoantibodies. 30% of children assigned a diagnosis of type 2 diabetes were autoantibody positive, and these had the highest glycated haemoglobin (HbA1c) levels at 12 months follow-up compared with other groups (p value for analysis of variance <0.001), although the sample size was small. Autoantibody positivity was similar between non-white and white children regardless of assay used (60.0% (n=129) vs 56.4% (n=57), χ2=0.9, p=0.35), as was mean GAD-65 autoantibody levels, but fewer non-white children had two or more autoantibodies detectable (13% (n=28) vs 27.7% (n=28), χ2=12.1, p=0.001). Conclusions Islet autoantibody positivity was associated with a more severe phenotype, as demonstrated by poorer glycaemic control, regardless of assigned diabetes subtype. Positivity did not differ by ethnic group.