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Double Jeopardy: a Patient's Tale of Two Concurrent Hypercalcaemic Syndromes

Overview
Journal BMJ Case Rep
Specialty General Medicine
Date 2020 Aug 27
PMID 32843465
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Abstract

Primary hyperparathyroidism (PHPT) is the most common cause of parathyroid hormone (PTH) dependent hypercalcaemia, however there are few reported cases of its co-occurrence in patients with familial hypocalciuric hypercalcaemia (FHH). This case highlights the challenges in managing a rare case of dual pathology. A 49-year-old Caucasian woman with symptoms of hypercalcaemia presented with an adjusted serum calcium of 2.77 mmol/L and PTH of 11.5 pmol/L. Neck ultrasound and sestamibi scan were concordant with a left lower parathyroid adenoma, and a preoperative dual-energy X-ray absorptiometry scan confirmed osteopenia. Parathyroidectomy resulted in a PTH reduction from 11.5 pmol/L to 2.7 pmol/L. Interestingly, her lowest pre-operative adjusted serum calcium of 2.67 mmol/L remained unchanged 14 months post-parathyroidectomy. Twenty-four hours urine calcium:creatinine clearance ratio performed postoperatively was low and sequencing analysis of the calcium-sensing receptor gene confirmed the coexistence of FHH. Although surgery is not indicated in FHH, parathyroidectomy may help reduce hypercalcaemia and its associated complications if there is coexistent PHPT.

References
1.
Pollak M, Brown E, Chou Y, Hebert S, Marx S, Steinmann B . Mutations in the human Ca(2+)-sensing receptor gene cause familial hypocalciuric hypercalcemia and neonatal severe hyperparathyroidism. Cell. 1993; 75(7):1297-303. DOI: 10.1016/0092-8674(93)90617-y. View

2.
Heath 3rd H, Jackson C, Otterud B, Leppert M . Genetic linkage analysis in familial benign (hypocalciuric) hypercalcemia: evidence for locus heterogeneity. Am J Hum Genet. 1993; 53(1):193-200. PMC: 1682230. View

3.
Lloyd S, Pannett A, Dixon P, Whyte M, Thakker R . Localization of familial benign hypercalcemia, Oklahoma variant (FBHOk), to chromosome 19q13. Am J Hum Genet. 1999; 64(1):189-95. PMC: 1377717. DOI: 10.1086/302202. View

4.
Marx S . Familial Hypocalciuric Hypercalcemia as an Atypical Form of Primary Hyperparathyroidism. J Bone Miner Res. 2017; 33(1):27-31. DOI: 10.1002/jbmr.3339. View

5.
Carling T, Szabo E, Bai M, Ridefelt P, Westin G, Gustavsson P . Familial hypercalcemia and hypercalciuria caused by a novel mutation in the cytoplasmic tail of the calcium receptor. J Clin Endocrinol Metab. 2000; 85(5):2042-7. DOI: 10.1210/jcem.85.5.6477. View