Abstract
Mendenhall's syndrome comprises insulin-resistant diabetes, pineal hyperplasia, and various somatic anomalies. A boy with this condition now aged 12 years is reported; a similarly affected sibling died aged 7.8 years. Hypophysectomy has been of short-term benefit, but the problems of insulin resistance persist. On the basis of monocyte-binding studies it seems likely that in this condition there is an inherited deficiency of insulin receptors.