title: Sporadic pseudohypoparathyroidism type-1b with asymptomatic hypocalcemia.
abstract: Pseudohypoparathyroidism type 1b (PHP-1b) is usually diagnosed on various symptoms of hypocalcemia. Previous studies reported a few cases of autosomal dominant pattern PHP-1b identified on familial analysis with asymptomatic hypocalcemia. Herein we report the case of a 6-year-old male patient with sporadic PHP-1b incidentally detected on preoperative examination. He had neither characteristic findings of Albright hereditary osteodystrophy nor evidence of tetany. Sporadic PHP-1b was diagnosed on the basis of clinical observation and laboratory examination. In addition, genetic testing using methylation-specific multiplex ligation-dependent probe amplification indicated broad methylation abnormalities and confirmed the sporadic form of PHP-1b. Sporadic PHP-1b might often be overlooked when diagnosis is done simply on definitive clinical features. To avoid this, DNA sequencing and methylation analysis should be performed even in the absence of definitive clinical features.
authors.affiliation: Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu City, Fukuoka, Japan.|Health Care & Support Center, General Affairs and Human Resources Office, Ube Industries, Ube City, Yamaguchi, Japan.
authors.forename: Motohide
authors.initials: M
authors.lastname: Goto
authors.affiliation: Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu City, Fukuoka, Japan.
authors.forename: Yukiyo
authors.initials: Y
authors.lastname: Yamamoto
authors.affiliation: Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu City, Fukuoka, Japan.
authors.forename: Masahiro
authors.initials: M
authors.lastname: Ishii
authors.affiliation: Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan.
authors.forename: Akie
authors.initials: A
authors.lastname: Nakamura
authors.affiliation: Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan.
authors.forename: Shinichiro
authors.initials: S
authors.lastname: Sano
authors.affiliation: Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan.
authors.forename: Masayo
authors.initials: M
authors.lastname: Kagami
authors.affiliation: Department of Molecular Endocrinology, National Research Institute for Child Health and Development, Tokyo, Japan.
authors.forename: Maki
authors.initials: M
authors.lastname: Fukami
authors.affiliation: Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu City, Fukuoka, Japan.
authors.forename: Reiko
authors.initials: R
authors.lastname: Saito
authors.affiliation: Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu City, Fukuoka, Japan.
authors.forename: Shunsuke
authors.initials: S
authors.lastname: Araki
authors.affiliation: Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu City, Fukuoka, Japan.
authors.forename: Kazuyasu
authors.initials: K
authors.lastname: Kubo
authors.affiliation: Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu City, Fukuoka, Japan.
authors.forename: Rinko
authors.initials: R
authors.lastname: Kawagoe
authors.affiliation: Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu City, Fukuoka, Japan.
authors.forename: Yasusada
authors.initials: Y
authors.lastname: Kawada
authors.affiliation: Department of Pediatrics, School of Medicine, University of Occupational and Environmental Health, Kitakyushu City, Fukuoka, Japan.
authors.forename: Koichi
authors.initials: K
authors.lastname: Kusuhara
mesh_terms: D002648:Child; D002864:Chromogranins / Q000235:genetics* / Q000378:metabolism; D004247:DNA / Q000235:genetics*; D004252:DNA Mutational Analysis; D019205:GTP-Binding Protein alpha Subunits, Gs / Q000235:genetics* / Q000378:metabolism; D005820:Genetic Testing; D006801:Humans; D006996:Hypocalcemia / Q000097:blood / Q000175:diagnosis / Q000209:etiology*; D008297:Male; D011547:Pseudohypoparathyroidism / Q000150:complications / Q000175:diagnosis* / Q000235:genetics
chemical_list: D002864:Chromogranins; D004247:DNA; C406732:GNAS protein, human; D019205:GTP-Binding Protein alpha Subunits, Gs
keywords: 
  
  GNAS
  
  ; asymptomatic hypocalcemia; methylation abnormality; methylation-specific multiplex ligation-dependent probe amplification; pseudohypoparathyroidism