August 14, 1999
Diagnosis and Symptoms
Question from America On-Line:
Do the newest guidelines for the diagnosis of diabetes apply to children as well as adults? At what age can the adult criteria be applied to adolescents?
The approach to diagnosis is different as between adults on the one hand and children and adolescents on the other. In most adults, diabetes represents a slowly progressive loss of glucose tolerance due to insulin resistance. In this situation it has proved useful to set, on the basis of experience, specific blood sugar levels above which it is justifiable to make a diagnosis and to start appropriate treatment and instruction. Both WHO and the American Diabetes Association have done this for fasting glucose level and for levels at 2 hours after a standard glucose load.
In children and adolescents in North America and western Europe, on the other hand, the great majority of diabetes is due to an autoimmune disorder with a slow destruction of islet tissue. The diagnosis here is made not so much on blood sugar levels as on the results of an antibody test. Of course there are exceptions, Type 1 cases may present occasionally in the adult years and Type 2 diabetes may begin in childhood as one of the various forms of MODY. Especially in Hispanic and African-American families there can be a clinical onset very similar to Type 1A but with a negative antibody test. In the very small proportion of these latter groups where the evidence of glucose intolerance is not obvious, the same WHO and ADA criteria may be helpful as may be more sophisticated tests such as insulin levels after a standard glucose load.