Aims: To estimate the UK prevalence of childhood type 2 diabetes and maturity onset diabetes of the young (MODY), and distinguish them from each other and from type 1 diabetes.

Methods: The British Society for Paediatric Endocrinology and Diabetes Clinical Trials/Audit Group undertook a cross-sectional questionnaire survey of all paediatric diabetes centres during 2000, collecting data on all children with non-type 1 diabetes.

Results: Of 112 children reported to the survey, 25 had type 2 diabetes and 20 had MODY. In contrast to type 1, type 2 patients presented later (12.8 v 9.3 years), were usually female, overweight, or obese (92% v 28%), and a greater proportion were of ethnic minority origin (56% v 22%). In contrast to type 2, MODY patients were younger (10.8 years), less likely to be overweight or obese (50% v 92%), and none were from ethnic minority groups. The crude minimum UK prevalence of type 2 diabetes under 16 years is 0.21/100 000, and of MODY is 0.17/100 000. South Asian children have a relative risk of type 2 diabetes of 13.7 compared to white UK children.

Conclusions: UK children still have a low prevalence of type 2 diabetes. Children from ethnic minorities are at significantly higher risk, but in white UK children with non-type 1 diabetes a diagnosis of MODY is as likely as type 2 diabetes. Childhood type 2 diabetes is characterised by insulin resistance, and is distinct from both type 1 and MODY.