An adolescent case of familial hyperparathyroidism with a germline frameshift mutation of the CDC73 gene

Primary hyperparathyroidism (PHPT) is common in the elderly, especially women, but is rare in children (1, 2). Most cases of PHPT are sporadic, and familial cases make up less than 10% of cases (2, 3), but onset in childhood or adolescence raises concern about familial diseases with a genetic background, e.g., multiple endocrine neoplasia (MEN), hyperparathyroidism-jaw tumor (HPT-JT), familial isolated hyperparathyroidism (FIHP), and familial hypocalciuric hypercalcemia (FHH) (4). To date, several CDC73 gene mutations in patients with HPT-JT and FIHP have been reported (2, 3, 5,6,7,8,9,10,11,12,13,14). HPT-JT and FIHP are autosomal dominant disorders, and hyperparathyroidism in these patients is often diagnosed in adolescence (15). We cared for an adolescent boy with hyperparathyroidism whose maternal grandmother and aunt, but not mother, had a history of parathyroid adenoma.