Semantic Scholar extracted the view of severe neonatal hyperparathyroidism caused by a homozygous mutation in CASR: a rare cause of life-threatening hypercalcemia. by Heidi J Murphy et al. 098, from all scientific fields. Research. Log in Create a free account. DOI: 10.1016 j.ejmg.2016.02.001A male infant who presented during the first month of life with symptoms of lethargy, constipation, and refusal to feed was diagnosed with neonatal hyperparathyroidism severe and underwent a total parathyroidectomy with auto-transplantation of half of her child. the left lower parathyroid gland. Severe neonatal hyperparathyroidism, Severe neonatal hyperparathyroidism NSHPT. is a rare disease with reported cases, 1 to 5 Half have been reported, the year of identification of the CASR gene and the year of first manifestation of frequent and probable pathogenic variants of CASR in NSHPT, 2, 3 Two NSHPT phenotypes with. The authors report a case presented in a female neonate, review the world literature, and discuss the clinical manifestations, investigators' findings, and available management options. Primary hyperparathyroidism in the newborn is exceptionally rare and is almost invariably fatal unless prompt diagnosis and urgent surgical intervention is made. Look for other articles by this author. Sunita K. Agarwal, Sunita K. Agarwal. MEN, A. Familial benign hypocalciuric hypercalcemia FHH, severe neonatal primary hyperparathyroidism NSHPT, hyperparathyroidism - jaw tumor syndrome HPT-JT and familial isolated primary hyperparathyroidism FIHPT; The case of a premature infant presenting with the onset of hypercalcemia and apparent primary hyperparathyroidism during the immediate neonatal period and its evolution support the assertion that this disorder may be self-limited in certain infants and that management appropriate medical burden may exclude the need for surgical intervention in selected cases; Background: Severe neonatal primary hyperparathyroidism NSPHPT is an extremely rare autosomal recessive disorder, requiring a high index of suspicion. Infants with this disorder are present.