Primary Hyperparathyroidism Accompanied By Recovery Of Parathyroid Blood Flow Three Months After Spontaneous Parathyroid Hemorrhage

Abstract

Objective: The objective of this report was to describe an unusual case of emerging primary hyperparathyroidism (PHPT) accompanied by recovery of parathyroid blood flow 3 months after spontaneous parathyroid hemorrhage. Methods: Neck images and laboratory tests including serum calcium and parathyroid hormone (PTH) were performed to evaluate parathyroid hemorrhage. Pathologic findings after parathyroidectomy are also presented. Results: A 58-year-old woman developed acute onset of neck pain and swelling with ecchymosis. Computed tomography showed a right para-tracheal hematoma-like lesion behind the thyroid. Ultrasound (US) of the neck revealed a round, hypoechoic nodule measuring 27 × 25 × 18 mm in the right lower thyroid pole without vascular flow. Blood tests showed corrected calcium 9.3 mg/dL (reference range: 8.7–10.3 mg/dL), intact PTH 68 pg/mL (reference range: 10–65 pg/mL). Intact PTH measurement in fine-needle aspirate of the lesion was 339 pg/mL, confirming parathyroid origin. Repeat US after 3 months showed remarkable decrease in lesion size with significant blood flow. Blood biochemistry showed was corrected calcium 10.9 mg/dL, intact PTH 237 pg/mL. She eventually underwent parathyroidectomy, and pathological examination revealed parathyroid adenoma with a tiny thrombus. Conclusion: Spontaneous remission of PHPT after parathyroid hemorrhage has been known to occur sporadically, a phenomenon referred to as autoparathyroidectomy. Although spontaneous remission with permanent improvement of PHPT may be observed, PHPT can recur in the relative short term after parathyroid hemorrhage, and so follow-up blood biochemistry surveillance is requisite. Aso, evaluating parathyroid blood flow using color Doppler US might be useful in verifying the recurrence of PHPT.