title: [Radiotransparent lithiasis. Diagnosis and treatment].
abstract: OBJECTIVE
  To analyze current clinical, diagnostic and therapeutic aspects of uric acid lithiasis. The role of helical CT in its diagnosis, ESWL and alkalinization in its treatment, and metabolic and crystalographic analyses are discussed.
  
  
  METHODS
  The incidence of uric acid calculi is estimated to be from 5% to 7% in the Lithiasis-Lithotripsy Unit of the Jiménez Díaz Foundation. The diagnostic and therapeutic possibilities of helical CT and ESWL are illustrated in a case of complex bilateral renal uric acid staghorn stone.
  
  
  RESULTS
  Ultrasound and endoscopic uroradiology are fundamental in the diagnosis of radiotransparent obstructive bilateral renal stone. Ureteral catheterization was warranted due to the anuresis that resulted from bilateral obstructive renal failure. Stone dissolution combined with ESWL achieved rapid resolution of the large calculi.
  
  
  CONCLUSIONS
  Helical CT without contrast enhancement should be performed along with the conventional urological diagnostic tests for ureteral lithiasis, especially in patients with renal colic. Although urinary alkalinization is the conventional treatment for uric acid stones, ESWL permits faster resolution in large, obstructive or ureteral stones in patients with renal colic. Complete assessment of patients with uric acid calculi includes metabolic and crystalographic analyses.
authors.affiliation: Servicio de Urología, Fundación Jiménez Díaz, Universidad Autónoma, Madrid, España. cganguita@fjd.es
authors.forename: C
authors.initials: C
authors.lastname: González Enguita
authors.forename: J L
authors.initials: JL
authors.lastname: Rodríguez Miñón-Cifuentes
authors.forename: E
authors.initials: E
authors.lastname: García de la Peña
authors.forename: J I
authors.initials: JI
authors.lastname: Jiménez Jiménez
authors.forename: R
authors.initials: R
authors.lastname: Vela Navarrete
mesh_terms: D000368:Aged; D005260:Female; D006801:Humans; D007669:Kidney Calculi / Q000175:diagnosis / Q000000981:diagnostic imaging* / Q000628:therapy; D011859:Radiography