title: Tyrosinemia type I: clinical and biochemical analysis of patients in Mexico.
abstract: BACKGROUND
  Hepatorenal tyrosinemia (HT1) is a treatable, inherited, metabolic disease characterized by progressive liver failure with pronounced coagulopathy. The aim of this study is to describe the clinical, biochemical, and histopathological findings in a group of Mexican HT1 patients and their outcome.
  
  
  METHODS
  Medical records of HT1 patients diagnosed between 1995 and 2011 were analyzed. The diagnosis of HT1 was confirmed by detection of succinylacetone in urine or blood.
  
  
  RESULTS
  Sixteen nonrelated HT1 cases were analyzed. Mean age at clinical onset was 9 months, and the mean age at diagnosis was 16.3 months. Main clinical findings were hepatomegaly, splenomegaly, cirrhosis, liver failure, tubulopathy, nephromegaly, Fanconi syndrome, seizures and failure to thrive. Histopathological findings were cirrhosis, fibrosis and steatosis. The HT1 group had a mortality rate of 78%. Patients who received supportive care or nutritional treatment had a 3-year survival rate of 10%. For those who underwent liver transplantation, the 6-year survival rate was 60%. In most cases pharmacological treatment with nitisinone and special dietary products were not available. The leading causes of death were fulminant liver failure, metastatic hepatocellular carcinoma, and porphyria-like neurologic crisis. Newborn screening programs in combination with the availability of orphan drugs, proper monitoring, genetic counseling, and clinical practice guidelines are needed to enable physicians to identify the disease, delay its progression, and improve patients' quality of life.
  
  
  CONCLUSIONS
  The devastating natural history of HT1 is still observed in Mexican patients because they are not diagnosed and treated during the early stages of the disease.
authors.affiliation: Laboratorio de Errores Innatos del Metabolismo y Tamiz del Instituto Nacional de Pediatría, Secretaría de Salud. México.
authors.forename: Cynthia
authors.initials: C
authors.lastname: Fernández-Lainez
authors.affiliation: Unidad de Genética de la Nutrición, Instituto de Investigaciones Biomédicas, UNAM-Instituto Nacional de Pediatría. México.
authors.forename: Isabel
authors.initials: I
authors.lastname: Ibarra-González
authors.affiliation: Laboratorio de Errores Innatos del Metabolismo y Tamiz del Instituto Nacional de Pediatría, Secretaría de Salud. México.
authors.forename: Leticia
authors.initials: L
authors.lastname: Belmont-Martínez
authors.affiliation: Laboratorio de Errores Innatos del Metabolismo y Tamiz del Instituto Nacional de Pediatría, Secretaría de Salud. México.
authors.forename: Susana
authors.initials: S
authors.lastname: Monroy-Santoyo
authors.affiliation: Laboratorio de Errores Innatos del Metabolismo y Tamiz del Instituto Nacional de Pediatría, Secretaría de Salud. México.
authors.forename: Sara
authors.initials: S
authors.lastname: Guillén-López
authors.affiliation: Laboratorio de Errores Innatos del Metabolismo y Tamiz del Instituto Nacional de Pediatría, Secretaría de Salud. México.
authors.forename: Marcela
authors.initials: M
authors.lastname: Vela-Amieva
mesh_terms: D003512:Cyclohexanones / Q000627:therapeutic use; D005260:Female; D006537:Heptanoates / Q000378:metabolism*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008099:Liver / Q000473:pathology*; D016031:Liver Transplantation; D008297:Male; D008403:Mass Screening / Q000379:methods; D008800:Mexico / Q000453:epidemiology; D009579:Nitrobenzoates / Q000627:therapeutic use; D044623:Nutrition Therapy; D012189:Retrospective Studies; D015996:Survival Rate; D020176:Tyrosinemias / Q000175:diagnosis* / Q000453:epidemiology / Q000628:therapy*
chemical_list: D003512:Cyclohexanones; D006537:Heptanoates; D009579:Nitrobenzoates; C020804:succinylacetone; C077073:nitisinone