title: Diagnosis of glucocorticoid-remediable aldosteronism in hypertensive children.
abstract: OBJECTIVE
  Glucocorticoid-remediable aldosteronism (GRA) is caused by the presence of a chimeric gene originating from an unequal cross-over between the CYP11B1 and CYP11B2 genes. Aldosterone suppression by dexamethasone and high 18-hydroxycortisol (18-OHF) levels have been used to differentiate GRA from the other forms of primary aldosteronism.
  
  
  METHODS
  A dexamethasone suppression test including serum 18-OHF determination and the measurement of urinary excretion of aldosterone, its metabolites and 18-OHF were performed in 3 children of a family with primary aldosteronism. Polymerase chain reactions were performed to identify the chimeric gene.
  
  
  RESULTS
  The chimeric gene was identified in 2 children, their mother and grandmother. The affected children had an aldosterone-to-plasma renin activity ratio >30, elevated serum 18-OHF concentration and increased urinary excretion of aldosterone, its metabolites, and 18-OHF. Post-dexamethasone concentrations of serum aldosterone and 18-OHF concentrations were suppressed.
  
  
  CONCLUSIONS
  Although very rare, the possible diagnosis of GRA should be considered in all children or young adults with low-renin hypertension. Since genetic testing is more specific than biochemical testing, a definitive diagnosis can only be obtained by identification of the CYP11B1/CYP11B2 chimeric gene.
authors.affiliation: Department of Paediatrics, Division of Paediatric Endocrinology, Justus Liebig University, Giessen, Germany. clemens.kamrath@paediat.med.uni-giessen.de
authors.forename: Clemens
authors.initials: C
authors.lastname: Kamrath
authors.forename: Christiane
authors.initials: C
authors.lastname: Maser-Gluth
authors.forename: Christine
authors.initials: C
authors.lastname: Haag
authors.forename: Egbert
authors.initials: E
authors.lastname: Schulze
mesh_terms: D000293:Adolescent; D000328:Adult; D000450:Aldosterone / Q000652:urine; D002648:Child; D002678:Chimera; D019405:Cytochrome P-450 CYP11B2 / Q000235:genetics; D003907:Dexamethasone; D005260:Female; D005938:Glucocorticoids / Q000627:therapeutic use; D006801:Humans; D006854:Hydrocortisone / Q000031:analogs & derivatives / Q000097:blood / Q000652:urine; D006929:Hyperaldosteronism / Q000175:diagnosis* / Q000188:drug therapy; D006973:Hypertension / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D010375:Pedigree; D012083:Renin / Q000097:blood; D013252:Steroid 11-beta-Hydroxylase / Q000235:genetics*
chemical_list: D005938:Glucocorticoids; D000450:Aldosterone; D003907:Dexamethasone; D019405:Cytochrome P-450 CYP11B2; D013252:Steroid 11-beta-Hydroxylase; D012083:Renin; C033689:18-hydroxycortisol; D006854:Hydrocortisone