title: Cysteamine toxicity in patients with cystinosis.
abstract: OBJECTIVE
  To report new adverse effects of cysteamine.
  
  
  METHODS
  Detailed clinical information was obtained from the patients' physicians.
  
  
  RESULTS
  New adverse events were reported in 8 of 550 patients with cystinosis treated with cysteamine in Europe during the last 5 years. Detailed clinical information was not available for 2 of these patients, 1 of whom died from cerebral ischemia. The 6 evaluable patients developed vascular elbow lesions (6/6), neurologic symptoms (1/6), bone and muscle pain (2/6), and/or skin striae (2/6). Analysis of biopsy specimens from the elbow lesions demonstrated angioendotheliomatosis with irregular collagen fibers. In 3 of the 6 patients, the daily cysteamine dose exceeded the recommended maximum of 1.95 g/m(2)/day. Dose reduction led to improvement of signs and symptoms in all 6 patients, suggesting a causal relationship with cysteamine administration.
  
  
  CONCLUSIONS
  Cysteamine administration can be complicated by the development of skin, vascular, neurologic, muscular, and bone lesions. These lesions improve after cysteamine dose reduction. Doses >1.95 g/m(2)/day should be prescribed with great caution, but underdosing is not advocated.
authors.affiliation: Department of Pediatric Nephrology, Laboratory of Pediatrics, University Hospitals Leuven, Leuven, Belgium.
authors.forename: Martine T P
authors.initials: MT
authors.lastname: Besouw
authors.forename: Richard
authors.initials: R
authors.lastname: Bowker
authors.forename: Jean-Paul
authors.initials: JP
authors.lastname: Dutertre
authors.forename: Francesco
authors.initials: F
authors.lastname: Emma
authors.forename: William A
authors.initials: WA
authors.lastname: Gahl
authors.forename: Marcella
authors.initials: M
authors.lastname: Greco
authors.forename: Marc R
authors.initials: MR
authors.lastname: Lilien
authors.forename: John
authors.initials: J
authors.lastname: McKiernan
authors.forename: François
authors.initials: F
authors.lastname: Nobili
authors.forename: Jerry A
authors.initials: JA
authors.lastname: Schneider
authors.forename: Flemming
authors.initials: F
authors.lastname: Skovby
authors.forename: Lambertus P
authors.initials: LP
authors.lastname: van den Heuvel
authors.forename: William G
authors.initials: WG
authors.lastname: Van't Hoff
authors.forename: Elena N
authors.initials: EN
authors.lastname: Levtchenko
mesh_terms: D002675:Child, Preschool; D003543:Cysteamine / Q000633:toxicity*; D003554:Cystinosis / Q000188:drug therapy*; D003875:Drug Eruptions / Q000209:etiology*; D006801:Humans; D007223:Infant; D008297:Male
chemical_list: D003543:Cysteamine