title: Thyroid developmental anomalies among first-degree relatives of children with thyroid dysgenesis and congenital hypothyroidism.
abstract: BACKGROUND
  Thyroid dysgenesis (TD) is usually sporadic. In approximately 2%-8% of TD cases, familial TD has been identified.
  
  
  OBJECTIVE
  The aim of this study is to define the prevalence of thyroid developmental anomalies in first-degree relatives of children with TD-caused congenital hypothyroidism (CH).
  
  
  METHODS
  The investigation included 102 relatives of 33 children with CH and TD (study group) and 27 relatives of 12 normal children (comparative group). All the individuals were subjected to thyroid ultrasound and serum thyroid stimulating hormone (TSH) and free T4 (FT4) determinations. Statistical analysis was based on Fisher's exact test.
  
  
  RESULTS
  TD-caused familial CH was noted in 2 of 33 (6%) children with CH. Asymptomatic thyroid developmental anomaly was seen in 1 of 102 (1%) relatives - left thyroid lobe hypoplasia in the mother of a girl with CH and thyroid severe hypoplasia. Familial prevalence of asymptomatic TD in the study group was observed in 1 of 32 families (3.13%). None of the comparative group members demonstrated any thyroid developmental anomalies.
  
  
  CONCLUSIONS
  The prevalence rate of thyroid developmental anomalies in the study group is slightly higher than in the comparative group. These disturbances are asymptomatic.
authors.affiliation: Department of Pediatric and Adolescent Endocrinology, Polish-American Children's Hospital, Collegium Medicum, Jagiellonian University, Cracow, Poland. mkumorowicz@kki.pl
authors.forename: Malgorzata
authors.initials: M
authors.lastname: Kumorowicz-Czoch
authors.forename: Dorota
authors.initials: D
authors.lastname: Tylek-Lemanskaz
authors.forename: Lukasz
authors.initials: L
authors.lastname: Wyrobek
authors.forename: Teresa
authors.initials: T
authors.lastname: Grodzicka
authors.forename: Jerzy
authors.initials: J
authors.lastname: Starzyk
mesh_terms: D000293:Adolescent; D002648:Child; D002675:Child, Preschool; D003409:Congenital Hypothyroidism / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000235:genetics*; D005190:Family; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D010375:Pedigree; D010641:Phenotype; D015995:Prevalence; D050033:Thyroid Dysgenesis / Q000000981:diagnostic imaging / Q000453:epidemiology* / Q000235:genetics*; D014463:Ultrasonography