title: [Diagnostic error of mental retardation of neurometabolic origin confirmed by mass sequential spectrometry].
abstract: BACKGROUND
  The metabolic screening test gives the first laboratory indication for neurometabolic alterations which can cause mental retardation. Some techniques such as thin layer chromatography, are still used in several countries to confirm the diagnosis of inborn errors of metabolism after a general screening test.
  
  
  METHODS
  Two patients from a mentally retarded Colombian population were reported positive for the Nitrosonaphtol test, and remained positive to tyrosine metabolism alteration by thin layer chromatography, suggesting the correspondent management. In the present study we tried to confirm the last diagnosis, performing tandem mass spectrometry analysis of acylcarnitines and amino acids, on blood samples of all patients from the last study, which were found negative for any alteration.
  
  
  CONCLUSIONS
  Is necessary to improve the diagnosis methods used in some countries in order to avoid mistakes that can change the life-style of the wrongly diagnosed patients.
authors.affiliation: Universidad de Caldas, Manizales, Colombia. Jose.Osorio-Orozco@ncl.ac.uk
authors.forename: J H
authors.initials: JH
authors.lastname: Osorio-Orozco
authors.forename: M
authors.initials: M
authors.lastname: Pourfarzam
mesh_terms: D001921:Brain / Q000378:metabolism*; D002648:Child; D002675:Child, Preschool; D003951:Diagnostic Errors; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000175:diagnosis* / Q000209:etiology*; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D010661:Phenylketonurias / Q000175:diagnosis; D014443:Tyrosine / Q000378:metabolism; D020176:Tyrosinemias / Q000150:complications* / Q000175:diagnosis
chemical_list: D014443:Tyrosine