Heterozygous CDC73 mutation causing hyperparathyroidism in children and adolescents: a report of 2 cases

Primary hyperparathyroidism (PHPT), whilst common in elderly populations, is rare in adolescents. Hereditary cases make up less than 10% of patients with PH. We report two patients with CDC73 mutation presenting in early adolescence.

Case 1: A 14-year-old patient was referred from an adolescent mental health unit with hypercalcaemia. Imaging revealed a parathyroid adenoma. Genetic testing of the patient showed a heterozygous deletion of CDC73. Case 2: A 10-year-old patient was admitted to the general paediatric ward with symptoms suggestive of hypercalcaemia. The patient was known to carry an autosomal dominant mutation of CDC73. Imaging of the parathyroid gland showed bilateral adenoma.

We present two patients with CDC73 defects, who both presented with symptoms of hypercalcaemia. The cases highlight the difference in paediatric populations with PHPT who are often symptomatic at the time of diagnosis when compared to adult patients.