title: Diagnosis of heterozygous familial hypercholesterolaemia in children.
abstract: BACKGROUND
  Most children with familial hypercholesterolaemia (FH) are diagnosed by raised blood cholesterol levels, but the test lacks sensitivity and specificity. As such children have evidence of vascular dysfunction at an early age, correct identification of affected individuals is important so that treatment can be started.
  
  
  OBJECTIVE
  To determine levels of total cholesterol (TC) and low-density lipoprotein cholesterol (LDL-C) in children with genetically proven FH and their unaffected siblings, in order to identify a diagnostic cut-off point if possible.
  
  
  METHODS
  Retrospective case-note survey.
  
  
  METHODS
  We studied the notes of 115 children aged 3-16 years, 69 proven FH and 46 unaffected sibs, 65 boys and 50 girls, from 31 families and 21 different mutations. Data recorded were age, sex, TC, and (when available) LDL-C.
  
  
  RESULTS
  The lowest TC level in an affected individual was 4.7 mmol/l and the highest in normal individual was 6.05 mmol/l. This overlap range included 21 children (18% of the total). The corresponding figures for LDL-C were 3.0 and 3.7 mmol/l, which included eight children (8%).
  
  
  CONCLUSIONS
  TC is not an effective test for differentiating affected and unaffected children with FH. LDL-C is better, but genetic testing remains the method of choice, especially if treatment decisions are to be taken.
authors.affiliation: Regional Lipid Clinic, Royal Victoria Hospital, Belfast, UK. paul.nicholls@belfasttrust.hscni.net
authors.forename: D P
authors.initials: DP
authors.lastname: Nicholls
authors.forename: M
authors.initials: M
authors.lastname: Cather
authors.forename: C
authors.initials: C
authors.lastname: Byrne
authors.forename: C A
authors.initials: CA
authors.lastname: Graham
authors.forename: I S
authors.initials: IS
authors.lastname: Young
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D002648:Child; D002675:Child, Preschool; D002784:Cholesterol / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D042241:Early Diagnosis; D005260:Female; D006579:Heterozygote; D006801:Humans; D006938:Hyperlipoproteinemia Type II / Q000175:diagnosis*; D008297:Male; D012189:Retrospective Studies
chemical_list: D015415:Biomarkers; D008078:Cholesterol, LDL; D002784:Cholesterol