title: Intravenous pamidronate in the treatment of severe idiopathic infantile hypercalcemia.
abstract: Idiopathic infantile hypercalcemia (IIH) is a rare disorder caused by CYP24A1 loss-of-function mutation, resulting in impaired degradation of 1,25-dihydroxyvitamin D3. Pamidronate, an intravenously administered bisphosphonate, which is a potent inhibitor of bone resorption, has been reported only once for treatment IIH. We present a case of a previously healthy 5-month-old boy with IIH, where calcemia peaked to 5 mmol/L. Treatment with methylprednisone and furosemide had only minor effects; therefore, 2 intravenous infusions of pamidronate (0.6 mg/kg per dose) corrected the serum calcium level to 2.95 mmol/L. Furthermore, CYP24A1 homozygous mutation p.R396W (c.1186c&gt;t) was identified in this patient, confirming the clinical diagnosis of IIH. In conclusion, IIH has a favorable outcome once properly detected and appropriately treated. Pamidronate has a beneficial effect in those patients with IIH where glucocorticoids and furosemide fail to meet the expectations. &nbsp;
authors.affiliation: Department of Pediatrics, Charles University in Prague, Faculty of Medicine in Hradec Kralove, Hradec Kralove, Czech Republic. skalovasylva@seznam.cz
authors.forename: Sylva
authors.initials: S
authors.lastname: Skalova
authors.forename: Lucie
authors.initials: L
authors.lastname: Cerna
authors.forename: Milan
authors.initials: M
authors.lastname: Bayer
authors.forename: Stepan
authors.initials: S
authors.lastname: Kutilek
authors.forename: Martin
authors.initials: M
authors.lastname: Konrad
authors.forename: Karl-Peter
authors.initials: KP
authors.lastname: Schlingmann
mesh_terms: D015415:Biomarkers / Q000378:metabolism; D050071:Bone Density Conservation Agents / Q000627:therapeutic use*; D002118:Calcium / Q000378:metabolism*; D002675:Child, Preschool; D003937:Diagnosis, Differential; D004164:Diphosphonates / Q000627:therapeutic use*; D006801:Humans; D006934:Hypercalcemia / Q000175:diagnosis / Q000188:drug therapy* / Q000235:genetics*; D007223:Infant; D008297:Male; D009154:Mutation; D000077268:Pamidronate; D013250:Steroid Hydroxylases / Q000235:genetics*; D016896:Treatment Outcome; D065668:Vitamin D3 24-Hydroxylase
chemical_list: D015415:Biomarkers; D050071:Bone Density Conservation Agents; D004164:Diphosphonates; D013250:Steroid Hydroxylases; C585549:CYP24A1 protein, human; D065668:Vitamin D3 24-Hydroxylase; D000077268:Pamidronate; D002118:Calcium