title: Cystinuria in children and young adults: success of monitoring free-cystine urine levels.
abstract: Medical treatment of cystinuria is often disappointing. Patients undergo frequent surgery, which is often followed by early relapse. The aim of our study was to evaluate the efficacy of medical treatment of cystinuria, to prevent formation or to reduce the numbers and dimensions of renal stones. Twenty cystinuric patients were treated with a combined approach, including cystine-binding drugs. Free and bound urine cystine levels were measured every 4 months. Drug dosage was adjusted to maintain free urine cystine level below 100 micromol/mmol creatinine. Eighteen patients completed the study; detection of new stones was reduced from 0.28 per year to 0.03 per year, and, in six patients, the numbers and dimensions of pre-existing renal stones were reduced. Surgery was required in one subject, and no relapse was observed 12 months afterwards. The dosage required to achieve target levels was closely correlated with patient body weight: older children required a lower dose. Medical management of cystinuria is feasible. The treatment must be personalised in children, as the amount of drug required is strictly dependent on body size.
authors: Nephrology and Urology Department, Bambino Gesù Children's Hospital and Research Institute, Piazza S. Onofrio 4, 00165 Rome, Italy. dellostrologo@opbg.net
authors: Luca
authors: L
authors: Dello Strologo
authors: Chiara
authors: C
authors: Laurenzi
authors: Antonia
authors: A
authors: Legato
authors: Anna
authors: A
authors: Pastore
mesh_terms: D000293:Adolescent; D000328:Adult; D000468:Alkalies / Q000008:administration & dosage; D002614:Chelating Agents / Q000008:administration & dosage; D002648:Child; D002675:Child, Preschool; D003553:Cystine / Q000378:metabolism*; D003555:Cystinuria / Q000175:diagnosis / Q000188:drug therapy* / Q000652:urine*; D004232:Diuretics / Q000008:administration & dosage; D016903:Drug Monitoring / Q000379:methods*; D006801:Humans; D007223:Infant; D010396:Penicillamine / Q000008:administration & dosage; D019357:Potassium Citrate / Q000008:administration & dosage; D011446:Prospective Studies; D017693:Sodium Bicarbonate / Q000008:administration & dosage; D008625:Tiopronin / Q000008:administration & dosage*; D014545:Urinary Calculi / Q000188:drug therapy / Q000517:prevention & control
chemical_list: D000468:Alkalies; D002614:Chelating Agents; D004232:Diuretics; D003553:Cystine; D017693:Sodium Bicarbonate; D008625:Tiopronin; D019357:Potassium Citrate; D010396:Penicillamine
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