A giant parathyroid cyst causing primary hyperparathyroidism in a pregnant woman: Case report and literature review

Primary hyperparathyroidism (PHPT) during pregnancy is rare, with the commonest cause being parathyroid adenoma. Parathyroid cysts represent 0.5% of parathyroid lesions. The diagnosis of PHPT requires elevated levels of calcium, along with elevated or non-suppressed parathormone levels. Conservative treatment prevails unless hypercalcemia persists. A 33-week pregnant woman with preeclampsia and a cervical tumor was diagnosed with PHPT due to a functioning cystic adenoma. She underwent a caesarean section at 36 weeks, delivering a low-birthweight live newborn. Six months post-caesarean section the patient underwent right inferior parathyroidectomy and right hemithyroidectomy, with histopathological findings consistent with a giant cyst parathyroid adenoma. At review three months. after surgery, there are no signs of the persistence of the disease. A giant functional parathyroid cyst causing PHPT and being identified in pregnancy is exceedingly rare. It is crucial to have a timely multidisciplinary diagnosis and management to avoid maternal and fetal complications.