Hypogonadotrophic variant of Klinefelter's syndrome. A case report.

A 16-year-old boy with 47,XXY chromosomal complement (Klinefelter's syndrome) presented with delayed puberty and apparent gonadotrophin deficiency. Despite an inadequate growth hormone response to insulin-induced hypoglycaemia and to L-dopa administration, his somatic growth was appropriate for his delay in pubertal development, increasing markedly on testosterone treatment. Patients with Klinefelter's syndrome may have abnormalities of neuro-endocrine regulation.