The World Health Organization proje

The World Health Organization projects that the global prevalence of diabetes will increase from 217 million cases in 2005 to 366 mil- lion by 2030 (ref. 1). Diabetes remains a widespread disease in adults and is now the second most common chronic disease in children. For unclear reasons, the rate of T1D, or autoimmune diabetes, in children is rising by 3% annually2–4, with a projected 70% increase in prevalence between 2004 and 2020 (ref. 5). Although T1D was once considered a pediatric disease, approximately one-fourth of affected individuals are now diagnosed during adulthood6. Concurrently, the rate of T2D, also called metabolic diabetes, has escalated exponen- tially in children since the early 1990s, related in part to the global obesity epidemic1,4,7,8. As recently as 20 years ago, the probability of a young child developing T2D, or an overweight adult developing T1D, was low enough that diagnostic and treatment decisions were initiated on the basis of epidemiologic assumptions. However, the simultaneous rise in incidence of T1D and T2D9,10 has resulted in considerable overlap in the patient populations and a paradigm shift for these previously easily distinguishable diseases. A fundamental problem in current diabetes care is that diagnostic tests are slow and costly, delaying definitive diagnosis and making this key test inacces- sible to regions of the globe with limited resources.