Sir.—The data of Frasier et al1 regarding an increased prevalence of antithyroid microsomal antibodies (AMAs) among Hispanic children with insulin-dependent diabetes mellitus are certainly intriguing and lend support to previous recommendations for routine thyroid screening in children with diabetes. However, I have the following questions and concerns regarding their data interpretation and conclusions:
1. While the authors point out the many problems with the performance and interpretation of assays for antithyroid antibodies, they also suggest that their data support an increased prevalence of AMA positivity in Hispanic diabetic children relative to non-Hispanic diabetic children. The authors do not, however, present their own data in a non-Hispanic population, and it is not clear that the assays used in previous studies are comparable with those used in their report.
2. The authors recommend careful clinical assessment for thyroid dysfunction, yet do not report whether their hypothyroid diabetics manifested any suggestive signs or