Postoperative hungry bone syndrome in primary hyperparathyroidism: A case report.

Rationale: Hungry bone syndrome (HBS) is a forgotten and underdiagnosed cause. Postoperative HBS refers to patients with high bone turnover before surgery, but after surgery, the inhibition of osteoclast resorption by intact parathyroid hormone suddenly decreases, resulting in a sudden increase in the amount of calcium resorbed by the bone, and a rapid, severe and persistent hypocalcemia, which may be accompanied by hypophosphatemia and hypomagnesemia. We present a case with information about HBS and related complications after parathyroidectomy (PTX).

Patient concerns: The patient was a 57-year-old woman who presented to the hospital with "pain in both ankles for more than 3 years and in both knees for more than 2 years."

Diagnoses: A parathyroid mass was found preoperative. Unilateral resection of the lesion was performed under general anesthesia. On gross examination, the mass was reddish brown in color, about 2.9 × 2.5 × 2.3 cm, with abundant blood supply. Postoperative pathology diagnosed parathyroid adenoma.

Interventions: The patient was diagnosed with HBS on day 3 post-PTX, which lasted for 9 days.

Outcomes: After active calcium supplementation and other pharmacological interventions, her test parameters gradually returned to normal and she was discharged on the 13th day after surgery.

Lessons: Using the case of a patient with primary hyperparathyroidism with HBS lasting 9 days after PTX for diagnosis and management, we aimed to summarize possible predictors and perioperative management strategies to reduce the incidence, severity, and duration of postoperative HBS.