title: Clinical and biochemical characteristics of patients with urea cycle disorders in a developing country.
abstract: OBJECTIVE
  To report the clinical and laboratory characteristics of urea cycle disorder (UCD) patients at a tertiary care center in a developing country.
  
  
  METHODS
  Retrospective study of clinical and laboratory data of UCD patients.
  
  
  RESULTS
  Thirty-seven UCD patients were studied, 31 symptomatic (high risk) patients (15 neonatal onset, 16 late onset) and 6 with positive neonatal screening. Argininosuccinate synthetase deficiency was the most frequent disease (17/37, 46%), followed by ornithine transcarbamylase (10/37, 27%), arginase (7/37, 19%), and argininosuccinate lyase (3/37, 8%) deficiencies. Mortality of symptomatic patients was 38% (10/26), neonatal onset had the worst outcome, with 50% of survival.
  
  
  CONCLUSIONS
  In Mexico, the mortality of the UCD patients is higher than those reported in other countries, and neurological sequels are frequent and severe. It is essential to implement practice guidelines for the professional management of these patients.
authors.affiliation: Laboratorio de Errores Innatos del Metabolismo y Tamiz, Unidad de Genética de la Nutrición, Instituto Investigaciones Biomédicas-UNAM-Instituto Nacional de Pediatría-SS., Ave. Imán #1, Piso 9, Col. Insurgentes-Cuicuilco, Delegación Coyoacán, CP 04530, México, D.F., México.
authors.forename: Isabel
authors.initials: I
authors.lastname: Ibarra-González
authors.forename: Cynthia
authors.initials: C
authors.lastname: Fernández-Lainez
authors.forename: Marcela
authors.initials: M
authors.lastname: Vela-Amieva
mesh_terms: D017668:Age of Onset; D002675:Child, Preschool; D003906:Developing Countries; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008607:Intellectual Disability / Q000150:complications; D056806:Urea Cycle Disorders, Inborn / Q000175:diagnosis / Q000401:mortality / Q000473:pathology*