Ann Pediatr Endocrinol Metab.  2018 Jun;23(2):107-111. 10.6065/apem.2018.23.2.107.

De novo a novel variant of CaSR gene in a neonate with congenital hypoparathyroidism

• Moon JE
• Lee SJ
• Park SH
• Kim J
• Jin DK
• Ko CW

• KMID: 2417769
• DOI: http://doi.org/10.6065/apem.2018.23.2.107

Abstract

Autosomal-dominant hypocalcemia with hypercalciuria (ADHH) is a genetic disease characterized by hypoparathyroidism with hypercalciuria. Most patients with ADHH have calcium-sensing receptor (CaSR) gene mutations. The CaSR gene controls parathyroid secretions, and mutations in this gene can be detected via changes in serum calcium level. The activating mutation of the CaSR gene results in familial or sporadic ADHH. Most activating mutations of the CaSR gene are reportedly de novo missense mutations. This is the first case report of a novel activating variant of the CaSR gene in a neonate with congenital hypoparathyroidism with hypomagnesemia and hypercalciuria. We also report the 3-month follow-up management of the patient.

Keyword

Hypercalciuric hypocalcemia; Hypoparathyroidism; Calcium-sensing receptors; Mutation

MeSH Terms

Calcium
Follow-Up Studies
Humans
Hypercalciuria
Hypocalcemia
Hypoparathyroidism*
Infant, Newborn*
Mutation, Missense
Receptors, Calcium-Sensing
Calcium
Receptors, Calcium-Sensing

Figure

• 

  Fig. 1. The serial changes in serum phosphate, magnesium, calcium, ionized calcium, i-PTH, and u-Ca/Cr ratio, and medication for 3 months, are shown. IV Cal, intravenous calcium; PO Cal, calcium carbonate per oral; IV Mg, intravenous magnesium; PO Mg, elemental magnesium per oral; i-PTH, intact parathyroid hormone; u-Ca/Cr, spot urine calcium/creatinine.

• 

  Fig. 2. We identified a novel variant of calcium-sensing receptor (CaSR) gene in the patient and no variant in her parents. A heterozygous A to T transition is shown at position 2474 in exon 7 of CaSR gene, changing Tyr to Phe (T825P).

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  Fig. 3. (A) Kidney ultrasonography shows multiple tiny calyceal stones(white arrows) in right kidney. (B) A 0.6-cm stone filling the left renal pelvis(white arrow). (A,B) There was no evidence of obstructive uropathy.

Reference

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