title: [Screening for congenital hypothyroidism, phenylketonuria, galactosemia and biotinidase deficiency in a sample of mentally retarded patients in the city of Havana].
abstract: BACKGROUND
  Congenital hypothyroidism (CH), phenylketonuria (PKU), galactosemia (GAL) and biotinidase deficiency (BD) are innate errors in metabolism that share varying degrees of mental retardation (MR) as a common characteristic. AIMS. The aim of our study was to screen individuals with MR of unknown origin for CH, PKU, GAL and BD.
  
  
  METHODS
  Venous blood samples were collected on SS 903 specimen collection paper from 55 individuals with MR of unspecific origin born within the period 1977 1997. CH diagnosis was performed through determination of total thyroxine (T4) and thyroid stimulating hormone (TSH), using the UMELISA T4 and neonatal TSH reagent kits, respectively, and the detection of PKU, GAL and BD was conducted by determining phenylalanine (Phe), total galactose (Gal) and biotinidase enzyme activity (Biot) using UMTEST PKU, GAL and BIOTINIDASA.
  
  
  RESULTS
  The mean values obtained for the analytes that were evaluated were: 0.8 mUI of TSH/L of total blood (EEM: 0.2), 113.1 nmol of T4/L of serum (EEM: 5.4), 67.7 mol of Phe/L of total blood (EEM: 0.1), 0.1 mmol of Gal/L of total blood (EEM: 0.01), and Biot activity was normal in all cases.
  
  
  CONCLUSIONS
  This study enabled us to determine the T4, TSH, Phe and Gal levels in a sample from the Cuban population with MR of unknown causation. In addition, slightly higher levels of T4 were found in children who had hyperkinesis
authors.affiliation: Laboratorio de Cribado Neonatal, Centro de Inmunoensayo, Instituto Superieur de Ciencias Médicas de La Habana, La Habana, Cuba. neivis@infomed.sld.cu
authors.forename: N
authors.initials: N
authors.lastname: Marrero-González
authors.forename: M
authors.initials: M
authors.lastname: Portuondo-Sao
authors.forename: R
authors.initials: R
authors.lastname: Lardoeyt-Ferrer
authors.forename: D
authors.initials: D
authors.lastname: Tassé-Vila
authors.forename: A
authors.initials: A
authors.lastname: Lantigua-Cruz
mesh_terms: D000581:Amidohydrolases / Q000172:deficiency*; D043523:Biotinidase; D003409:Congenital Hypothyroidism; D005260:Female; D005693:Galactosemias / Q000175:diagnosis / Q000453:epidemiology*; D006801:Humans; D007037:Hypothyroidism / Q000175:diagnosis / Q000453:epidemiology*; D007231:Infant, Newborn; D008607:Intellectual Disability / Q000175:diagnosis / Q000453:epidemiology*; D008297:Male; D008403:Mass Screening; D010661:Phenylketonurias / Q000175:diagnosis / Q000453:epidemiology*; D015995:Prevalence; D013972:Thyrotropin / Q000097:blood; D013974:Thyroxine / Q000097:blood
chemical_list: D013972:Thyrotropin; D000581:Amidohydrolases; D043523:Biotinidase; D013974:Thyroxine