[Primary hyperparathyroidism in pregnancy resulting in hypercalcemic crisis and acute pancreatitis: A case report]

Primary hyperparathyroidism (PHPT) is caused by excessive production of parathyroid hormone by the parathyroid gland. PHPT discovered for the first time during pregnancy is extremely rare and has serious adverse effects on both the mother and the fetus. This article reports a case of pregnancy complicated by PHPT, hypercalcemic crisis, and acute pancreatitis. The patient was a 30-year-old woman at 32 weeks of gestation who presented with a four-day history of progressive abdominal pain and vomiting. Laboratory evaluation on admission revealed a markedly elevated serum total calcium of 3.56 mmol/L and a parathyroid hormone (PTH) level of 388.6 ng/L, with the normal reference range being 15 to 65 ng/L. Imaging studies confirmed the presence of acute pancreatitis, left nephrolithiasis, right hydronephrosis, and a suspicious cystic-solid mass at the lower pole of the right thyroid lobe measuring 2.1 cm × 2.0 cm × 1.2 cm. Due to rapid clinical deterioration and the development of a hypercalcemic crisis, an emergency cesarean section was performed, resulting in the delivery of a live premature male infant with a birth weight of 2 400 g and a length of 45 cm. The neonate's initial serum calcium was 3.08 mmol/L, and several episodes of hypocalcemic seizures occurred shortly after birth, necessitating admission to the neonatal intensive care unit. Postpartum, the mother was managed with aggressive intravenous fluid resuscitation, subcutaneous calcitonin, and intravenous bisphosphonate therapy. Notably, her serum PTH level decreased substantially after delivery, ranging from 48.91 to 53.08 ng/L. This spontaneous decline was likely attributable to reduced effective circulating blood volume during the episode of acute pancreatitis and partial ischemic necrosis of the parathyroid adenoma. At 47 days postpartum, the patient underwent successful surgical resection of a right inferior parathyroid adenoma measuring approximately 3 cm in diameter. Pathological examination of the resected specimen confirmed the diagnosis and revealed focal vascular proliferation and congestion, interstitial fibrosis with hyaline degeneration, and hemosiderin deposition. Following parathyroidectomy, her serum calcium and PTH levels normalized rapidly and remained stable. At the 9-month follow-up visit, the mother was completely asymptomatic with normal biochemical parameters, and the infant demonstrated appropriate growth and development. Clinicians should be vigilant about the presence of PHPT during pregnancy, especially during preconception and early pregnancy, monitoring blood calcium levels and taking preventive measures early to avoid complications and adverse pregnancy outcomes.