Primary infantile hyperparathyroidism: clinical, laboratory, and radiographic features in 21 cases.

Two cases of primary infantile hyperparathyroidism (PIH) are reported. In both cases the diagnosis was initially suspected from chest radiographs which were obtained to assess the etiology of fever and respiratory distress in one case and heart murmur in another. The first case responded well to subtotal parathyroidectomy. The second case had many unique features. (1) She never became overtly symptomatic. (2) She displayed a constellation of findings that are not yet emphasized. (3) Her indisputable radiographic findings of hyperparathyroidism vanished spontaneously by two months of age, whereas her biochemical alteration have persisted up to now, 2 1/2 years after birth. (4) There members of her family have subclinical hyperparathyroidism (elevated serum parathormone, hypercalcemia, and hypophosphatemia). Our review of 19 more cases showed that PIH has no specific clinical symptoms and/or signs. Of the laboratory findings, hypercalcemia was most consistently encountered. The radiographic findings, although not identical to those described in hyperparathyroid adults, had the greatest diagnostic specificity. The disorder carried a grave prognosis if not diagnosed promptly and managed surgically.