Far-advanced primary hyperparathyroidism in an 18-year-old young man.

Advanced debilitating primary hyperparathyroidism has become a clinical rarity as the condition is diagnosed at an asymptomatic stage in more patients. An 18-year-old young man is described who was referred because of an expanding facial mass. Evaluation revealed the classic musculoskeletal findings of severe primary hyperparathyroidism, as originally reported in the early part of the century.