title: Hypothyroidism Associated with ATP8B1 Deficiency.
abstract: OBJECTIVE
  To examine whether hypothyroidism is an extrahepatic feature of ATPase, aminophospholipid transporter, class I, type 8B, member 1 (ATP8B1) deficiency.
  
  
  METHODS
  Children with normal γ-glutamyltransferase cholestasis (n = 47; 13 patients with ATP8B1 deficiency, 19 with ATP-binding cassette, subfamily B (MDR/TAP), member 11 (ABCB11) deficiency, and 15 without either ATP8B1 or ABCB11 mutations) were enrolled. Clinical information and thyroid function test results were retrospectively retrieved from clinical records and compared. Hypothyroidism was diagnosed by clinical-biochemistry criteria (thyroid function test results).
  
  
  RESULTS
  Three out of 13 patients with ATP8B1 deficiency were diagnosed as hypothyroid and 2 as subclinically hypothyroid. The frequency of hypothyroidism and subclinical hypothyroidism was significantly higher than in patients with ABCB11 deficiency (5/13 vs 0/19, P = .006) and in patients without ATP8B1 or ABCB11 mutations (5/13 vs 0/15, P = .013). Thyroid function test results normalized after hormone replacement in all 5 patients, with no relief of cholestasis.
  
  
  CONCLUSIONS
  As hypothyroidism can be another extrahepatic feature of ATP8B1 deficiency, thyroid function should be monitored in these patients.
authors.affiliation: Department of Pediatrics, Shanghai Medical College, Fudan University, Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China.
authors.forename: Liting
authors.initials: L
authors.lastname: Li
authors.affiliation: Institute of Liver Studies, King's College Hospital, London, United Kingdom.
authors.forename: Maesha
authors.initials: M
authors.lastname: Deheragoda
authors.affiliation: Department of Pediatrics, Shanghai Medical College, Fudan University, Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China.
authors.forename: Yi
authors.initials: Y
authors.lastname: Lu
authors.affiliation: Department of Pediatrics, Jinshan Hospital, Fudan University, Shanghai, China.
authors.forename: Jingyu
authors.initials: J
authors.lastname: Gong
authors.affiliation: Department of Pediatrics, Shanghai Medical College, Fudan University, Center for Pediatric Liver Diseases, Children's Hospital of Fudan University, Shanghai, China; Department of Pediatrics, Jinshan Hospital, Fudan University, Shanghai, China. Electronic address: jshwang@shmu.edu.cn.
authors.forename: Jianshe
authors.initials: J
authors.lastname: Wang
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics* / Q000378:metabolism; D002648:Child; D002675:Child, Preschool; D004247:DNA / Q000235:genetics*; D004252:DNA Mutational Analysis; D005260:Female; D006801:Humans; D007037:Hypothyroidism / Q000097:blood / Q000235:genetics*; D008297:Male; D009154:Mutation; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies
chemical_list: D004247:DNA; D000251:Adenosine Triphosphatases; C111067:ATP8B1 protein, human