title: An instructive case suggesting cyclical primary hyperparathyroidism.
abstract: We report an instructive case of primary hyperparathyroidism in which cyclical secretion of PTH may have caused repeated hypercalcemic crises followed by temporary remission with a spontaneous drop in PTH. A 64-year-old man was admitted to our hospital twice with severe hypercalcemic crisis (corrected calcium (cCa) 15.0 mg/dl and 16.7 mg/dl) accompanied by an increase in intact PTH (220 pg/ml and 470 pg/ml). During both events, the serum PTH values spontaneously dropped followed by remission of the hypercalcemia. The tumor, detected at the left-upper side, showed neither vascularity on ultrasound examination nor washout delay on MIBI scintigraphy, suggesting that two parathyroid adenoma infarctions had occurred. Cervical exploration was undertaken. The histopathological examinations confirmed that the tumor was parathyroid adenoma. Contrary to our expectation, however, it did not reveal necrotic tissue that would indicate recent infarction. The findings in this case may be explained by cyclical secretion of PTH from a parathyroid adenoma. Although cyclical Cushing's syndrome is well known, to our knowledge this is the first documented case suggesting cyclical primary hyperparathyroidism.
authors.affiliation: Department of Endocrinology and Nephrology, University of Tokyo School of Medicine, Tokyo, Japan.
authors.forename: Noriko
authors.initials: N
authors.lastname: Makita
authors.forename: Taroh
authors.initials: T
authors.lastname: Iiri
authors.forename: Junichiro
authors.initials: J
authors.lastname: Sato
authors.forename: Seiji
authors.initials: S
authors.lastname: Fukumoto
authors.forename: Tomoki
authors.initials: T
authors.lastname: Okazaki
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Yamazaki
authors.forename: Takao
authors.initials: T
authors.lastname: Obara
authors.forename: Toshiro
authors.initials: T
authors.lastname: Fujita
mesh_terms: D015519:Bone Density; D006801:Humans; D006934:Hypercalcemia / Q000209:etiology; D049950:Hyperparathyroidism, Primary / Q000150:complications / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D010280:Parathyroid Glands / Q000000981:diagnostic imaging / Q000378:metabolism; D010281:Parathyroid Hormone / Q000378:metabolism; D012008:Recurrence; D014055:Tomography, Emission-Computed
chemical_list: D010281:Parathyroid Hormone