title: Effect of age at treatment on cognitive performance in patients with cystinosis.
abstract: OBJECTIVE
  To determine whether early treatment with cysteamine affects cognitive functioning in patients with nephropathic cystinosis.
  
  
  METHODS
  Forty-six subjects aged 3-18 years with cystinosis underwent cognitive testing to determine intelligence, visual-spatial abilities, and visual-motor skills. An age-matched control group (n = 85; age 2-22 years) underwent the same tests. Age at diagnosis and age at initiation of treatment with cysteamine were recorded at the time of testing.
  
  
  RESULTS
  Patients with cystinosis treated at or after age 2 years (late-treatment group) scored significantly lower on verbal, performance, and full-scale IQ measures, as well as on a test of visual-spatial skills, compared with patients treated before age 2 years (early-treatment group) and controls. Both groups of subjects with cystinosis demonstrated impaired visual-motor skills compared with controls, with no difference between the early-treatment and late-treatment groups.
  
  
  CONCLUSIONS
  Early treatment with cysteamine appears to improve intellectual function in patients with nephropathic cystinosis. However, the lack of improvement in visual-motor function with early cysteamine treatment suggests possibly different mechanisms underlying visual-motor performance compared with other areas of cognition in this disorder.
authors: Department of Neurosciences, University of California San Diego School of Medicine, La Jolla, CA 92093-0935, USA.
authors: Lisa
authors: L
authors: Viltz
authors: Doris A
authors: DA
authors: Trauner
mesh_terms: D000293:Adolescent; D000367:Age Factors; D002648:Child; D002675:Child, Preschool; D003071:Cognition; D003072:Cognition Disorders / Q000209:etiology / Q000517:prevention & control; D003543:Cysteamine / Q000627:therapeutic use*; D005198:Fanconi Syndrome / Q000150:complications / Q000188:drug therapy* / Q000523:psychology*; D006801:Humans; D055815:Young Adult
chemical_list: D003543:Cysteamine
keywords: Beery-Buktenica Developmental Test of Visual-Motor Integration; VMI