title: Molecular diagnosis of pseudohypoparathyroidism type Ib in a family with presumed paroxysmal dyskinesia.
abstract: We describe 2 sisters diagnosed initially with paroxysmal kinesigenic choreoathetosis, a condition characterized by brief episodes of spasms precipitated by sudden movement. However, subsequent testing showed hypocalcemia, hyperphosphatemia, and elevated parathyroid hormone levels consistent with pseudohypoparathyroidism type Ib. This diagnosis was confirmed by genetic testing, which identified a 3-kilobase deletion on chromosome 20q13.3. Our report describes the neurologic presentation, metabolic derangement, and underlying genetic mutation in a family. It also reinforces the importance of metabolic testing in the evaluation of pediatric patients with movement disorders.
authors.affiliation: Department of Pediatric Endocrinology and Metabolism, Mayo Clinic, Rochester, Minnesota 55905, USA. lteif.aida@mayo.edu
authors.forename: Farid H
authors.initials: FH
authors.lastname: Mahmud
authors.forename: Agnès
authors.initials: A
authors.lastname: Linglart
authors.forename: Murat
authors.initials: M
authors.lastname: Bastepe
authors.forename: Harald
authors.initials: H
authors.lastname: Jüppner
authors.forename: Aida N
authors.initials: AN
authors.lastname: Lteif
mesh_terms: D002648:Child; D002819:Chorea / Q000175:diagnosis*; D002872:Chromosome Deletion; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D006996:Hypocalcemia / Q000175:diagnosis; D010375:Pedigree; D010758:Phosphorus / Q000097:blood; D011547:Pseudohypoparathyroidism / Q000175:diagnosis* / Q000235:genetics
chemical_list: D010758:Phosphorus