title: Effect of hydrochlorothiazide on urinary calcium excretion in dent disease: an uncontrolled trial.
abstract: BACKGROUND
  Thiazide doses equivalent to 1 to 2 mg/kg/d of hydrochlorothiazide (HCTZ) have been proposed to correct hypercalciuria and prevent kidney failure in patients with Dent disease. However, they can cause adverse metabolic effects in the long term. In treating hypertension in children, lower thiazide doses have been shown to be as effective and well tolerated.
  
  
  METHODS
  Uncontrolled trial, with forced-titration sequential open-label study design.
  
  
  METHODS
  7 boys with genetically confirmed Dent disease and mild phenotype (neither overt sodium wasting nor kidney failure).
  
  
  METHODS
  After a 1-month run-in period, patients sequentially received amiloride (5 mg/d) alone (1 month) and then for 3 periods of 2 months in association with increasing doses of HCTZ (<0.2, 0.2 to 0.4, and 0.4 to 0.8 mg/kg/d).
  
  
  RESULTS
  Urinary calcium excretion and extracellular volume indicators.
  
  
  METHODS
  At the end of each period, 2 daily 24-hour urinary collections were performed on the days preceding admission. Blood and spot urine samples also were collected.
  
  
  RESULTS
  A greater HCTZ dose increased renin, aldosterone, and plasma protein concentrations. Amiloride alone had no effect on calcium excretion. The greatest HCTZ doses decreased spot urinary calcium excretion by 42% compared with baseline (median, 0.3; minimum, maximum, 0.2, 0.8 versus median, 0.8; minimum, maximum, 0.4, 1.1, respectively; P = 0.03). However, patients developed adverse reactions, including muscle cramps (n = 2), biological (n = 7) or symptomatic hypovolemia (n = 1), hypokalemia (n = 4), and hyponatremia (n = 1), which all corrected after treatment withdrawal.
  
  
  CONCLUSIONS
  Small sample size and absence of a control group.
  
  
  CONCLUSIONS
  HCTZ doses greater than 0.4 mg/kg/d decreased calcium excretion, but were associated with significant adverse events. Thiazide diuretic therapy should be considered with caution in children with Dent disease.
authors.affiliation: Université Paris 5, Faculté de Médecine Paris Descartes, Paris, France. anne.blanchard@egp.aphp.fr
authors.forename: Anne
authors.initials: A
authors.lastname: Blanchard
authors.forename: Rosa
authors.initials: R
authors.lastname: Vargas-Poussou
authors.forename: Severine
authors.initials: S
authors.lastname: Peyrard
authors.forename: Agnes
authors.initials: A
authors.lastname: Mogenet
authors.forename: Veronique
authors.initials: V
authors.lastname: Baudouin
authors.forename: Bernard
authors.initials: B
authors.lastname: Boudailliez
authors.forename: Marina
authors.initials: M
authors.lastname: Charbit
authors.forename: George
authors.initials: G
authors.lastname: Deschesnes
authors.forename: Nadia
authors.initials: N
authors.lastname: Ezzhair
authors.forename: Chantal
authors.initials: C
authors.lastname: Loirat
authors.forename: Marie-Alice
authors.initials: MA
authors.lastname: Macher
authors.forename: Patrick
authors.initials: P
authors.lastname: Niaudet
authors.forename: Michel
authors.initials: M
authors.lastname: Azizi
mesh_terms: D000293:Adolescent; D002118:Calcium / Q000652:urine*; D002648:Child; D004232:Diuretics / Q000008:administration & dosage*; D006801:Humans; D006852:Hydrochlorothiazide / Q000008:administration & dosage*; D053565:Hypercalciuria / Q000188:drug therapy* / Q000652:urine*; D017674:Hypophosphatemia / Q000188:drug therapy* / Q000652:urine*; D008297:Male; D011507:Proteinuria / Q000188:drug therapy* / Q000652:urine*; D000608:Renal Aminoacidurias / Q000188:drug therapy* / Q000652:urine*; D013577:Syndrome
chemical_list: D004232:Diuretics; D006852:Hydrochlorothiazide; D002118:Calcium