title: Blood erythrocyte and hemoglobin concentrations in premature adrenarche.
abstract: BACKGROUND
  Premature adrenarche (PA) is characterized by an earlier than normal increase in adrenocortical androgen production, and it is associated with increased serum IGF-I concentrations. Both the GH-IGF system and androgens, particularly testosterone, are known to enhance erythropoiesis.
  
  
  OBJECTIVE
  Our objective was to test the hypothesis that blood erythrocyte count and blood hemoglobin (B-Hb) concentration are increased in PA.
  
  
  METHODS
  Sixty-four prepubertal children (10 boys) with clinically and biochemically defined PA and 62 healthy prepubertal controls (10 boys) participating in our Premature Adrenarche study were examined, and a fasting blood sample was drawn at a university hospital.
  
  
  METHODS
  We evaluated B-Hb and erythrocyte, thrombocyte, and leukocyte counts and their association with serum dehydroepiandrosterone sulfate (DHEAS), testosterone and IGF-I concentrations.
  
  
  RESULTS
  Children with PA had higher mean blood erythrocyte count (4.74 vs. 4.64 × 10(12)/liter, P = 0.04; significant difference in girls but not in boys) and a tendency toward higher B-Hb (130 vs. 128 g/liter, P = 0.06) than their controls. No difference was observed in leukocyte or thrombocyte counts between the study groups. In linear regression models including age, sex, body mass index SD score, IGF-I, and DHEAS or testosterone, B-Hb was associated with serum DHEAS (P = 0.04), testosterone (P = 0.01), and IGF-I (P ≤ 0.003) concentrations in the entire study cohort and with IGF-I separately in girls (P ≤ 0.02). Similar models showed a significant association of blood erythrocyte count with serum IGF-I concentration (P = 0.003-0.049) but not with DHEAS or testosterone.
  
  
  CONCLUSIONS
  Increased erythrocyte count in PA girls suggests that relatively small increases in serum androgen or IGF-I concentrations during adrenarche may associate with enhanced erythropoiesis.
authors.affiliation: Department of Pediatrics, Kuopio University Hospital and University of Eastern Finland, P.O. Box 1777, FI-70211 Kuopio, Finland. pauliina.utriainen@uef.fi
authors.forename: Pauliina
authors.initials: P
authors.lastname: Utriainen
authors.forename: Jarmo
authors.initials: J
authors.lastname: Jääskeläinen
authors.forename: Raimo
authors.initials: R
authors.lastname: Voutilainen
mesh_terms: D050499:Adrenarche / Q000097:blood*; D000367:Age Factors; D016022:Case-Control Studies; D002648:Child; D002675:Child, Preschool; D019314:Dehydroepiandrosterone Sulfate / Q000097:blood; D004906:Erythrocyte Count; D004912:Erythrocytes / Q000166:cytology*; D005260:Female; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D007334:Insulin-Like Growth Factor I / Q000032:analysis; D008297:Male; D009994:Osmolar Concentration; D011629:Puberty, Precocious / Q000097:blood*
chemical_list: D006454:Hemoglobins; D019314:Dehydroepiandrosterone Sulfate; D007334:Insulin-Like Growth Factor I