Neonatal severe hyperparathyroidism secondary to a novel homozygous CASR gene mutation.
PMID 29354167 | PMCID PMC5762229 | DOI 10.11138/ccmbm/2017.14.3.354 · Clinical cases in mineral and bone metabolism : the official journal of the Italian Society of Osteoporosis, Mineral Metabolism, and Skeletal Diseases · 2017
Neonatal severe hyperparathyroidism (NSHPT) is a rare autosomal recessive disease. Children present within the first 6 months of life and more commonly in the first few weeks. Common presentation is poor feeding, polyuria, dehydration, lethargy, failure to thrive, hypotonia, gastrointestinal dysmotility, osteopenia and symptoms of respiratory distress due to a poorly developed chest cage. We present a case of a 2-month old girl with severe hypercalcemia and hyperparathyroidism. She was found to have a novel homozygous mutation in the acceptor splicing site of intron 4 (c.1378 -2A>G) of the calcium sensing receptor gene (CASR). This mutation causes frame shift deletion of exon 5 and insensitivity of CASR to calcium. The patient was treated with intravenous fluids, fruosemide, calcitonin, intravenous pamidronate and oral cinacalcet. She did not respond to medical treatment. Parathyroid gland imaging including ultrasound, MRI and sestamibi nuclear scan were not helpful in localizing the glands. Her symptoms resolved following total parathyroidectomy. She is being treated with alfacalcidiol and calcium supplements to maintain normal serum calcium and phosphate. She achieved her normal developmental milestones.
Validated evidence
| Type | Entity | Source evidence | Confidence | Extractor |
|---|---|---|---|---|
| gene | CASR | “Neonatal severe hyperparathyroidism secondary to a novel homozygous CASR gene mutation.” | 0.98 | hgnc_dict_v1 |
| variant | -2A>G | “She was found to have a novel homozygous mutation in the acceptor splicing site of intron 4 (c.1378 -2A>G) of the calcium sensing receptor gene (CASR).” | 0.82 | literature_variant_regex_v2 |