title: Is calcium signaling relevant for long bone growth?
abstract: BACKGROUND
  Neonatal severe hyperparathyroidism (NSHPT) is a rare autosomal recessive disorder of calcium homeostasis, more often induced by homozygous inactivating mutations of the calcium-sensing receptor gene. This rare syndrome can be lethal if total parathyroidectomy is not performed within the first weeks of life.
  
  
  METHODS
  We report the clinical case of a male patient, son of consanguineous hypercalcemic parents, with clinical and biochemical features of NSHPT, followed until the age of 21 years. The patient underwent total parathyroidectomy, and then, due to the low compliance to calcium and calcitriol supplementation, an attempt was made with recombinant human parathyroid hormone [rhPTH (1-84)]. The patient did not reach the predicted height with an increased ratio of the upper and lower segments.
  
  
  CONCLUSIONS
  While this case is unique for the length of follow-up, the continuous and detailed description of NSHPT after total parathyroidectomy in its adult phenotype, and the treatment of hypoparathyroidism with rhPTH (1-84). Following this first description of a statural defect due to shortening of long bones in NSHPT, future investigations will attempt to uncover the role of calcium signaling in growth plate cartilage in humans.
authors.affiliation: Bone and Mineral Metabolism Unit, Department of Internal Medicine, University of Florence Medical School, Florence, Italy.
authors.forename: Gemma
authors.initials: G
authors.lastname: Marcucci
authors.forename: Laura
authors.initials: L
authors.lastname: Masi
authors.forename: Loredana
authors.initials: L
authors.lastname: Cavalli
authors.forename: Caterina
authors.initials: C
authors.lastname: Fossi
authors.forename: Francesco
authors.initials: F
authors.lastname: Franceschelli
authors.forename: Maria Luisa
authors.initials: ML
authors.lastname: Brandi
mesh_terms: D000293:Adolescent; D001846:Bone Development / Q000235:genetics / Q000502:physiology*; D020013:Calcium Signaling / Q000235:genetics / Q000502:physiology*; D002648:Child; D002675:Child, Preschool; D006801:Humans; D006961:Hyperparathyroidism / Q000235:genetics / Q000503:physiopathology; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010281:Parathyroid Hormone / Q000235:genetics / Q000378:metabolism; D055815:Young Adult
chemical_list: C470125:PTH protein, human; D010281:Parathyroid Hormone
keywords: CaSR; Calcium-sensing receptor; Growth plate cartilage; Hypercalcemia; NSHPT; Neonatal severe hyperparathyroidism; PTH; Parathyroid hormone; Primary hyperparathyroidism; Severe neonatal hyperparathyroidism; Statural defects