Outcome of Clinical Genetic Testing in Patients with Features Suggestive for Hereditary Predisposition to PTH-mediated Hypercalcemia

Primary hyperparathyroidism (pHPT) is associated with familial syndromes such as multiple endocrine neoplasia type 1 (MEN1), 2A (MEN2A), MEN-like syndromes (CDKN1B), and CDC73-related disorder (hyperparathyroidism – jaw tumor syndrome (HPJT)). Familial hypocalciuric hypercalcemia (FHH) caused by CASR variants is an important differential diagnosis for pHPT. In order to evaluate the contribution of hereditary causes to pHPT in patients encountered in a specialized clinic, we conducted a retrospective study on patients with pHPT that underwent germline genetic testing. We evaluated 46 patients referred to a Cancer Genetics Clinic. Reasons for referral were young age (age