title: [Blood and urine lead levels in children with attention deficit hyperactivity disorder].
abstract: BACKGROUND
  Attention deficit hyperactivity disorder is the most common neuropsychiatric disorder in children; symptoms can persist into adult life by 60 %. Our objective was to quantify the levels of lead in blood and urine in pediatric patients with attention deficit hyperactivity disorder.
  
  
  METHODS
  We did an observational study which included a captive population of children diagnosed with attention deficit hyperactivity disorder in the mental health service of Hospital General, from Centro Médico Nacional La Raza. Lead levels were determined in blood and urine by atomic absorption technique.
  
  
  RESULTS
  We included 39 patients, 932 % male, with a mean age of 9.2 ± 2.16 years. The deficit and hyperactivity disorder combined type was the most frequent (69.2 %); 49 % of patients were found with toxic lead levels in blood (above 10 mg/dL); 17.9 % with stage III and 5.12 % with stage IV, according to the Mexican Official Standard (NOM-199-SSA-2000). Significant association was found between blood lead levels and the clinical expression of attention deficit hyperactivity disorder.
  
  
  CONCLUSIONS
  Levels of lead exposure during early childhood have been shown to be inversely proportional to neurological development in the first seven years of life. Data results are insufficient to relate them with causality.
authors.affiliation: Servicio de Urgencias Pediátricas y Centro de Información y Asistencia Toxicológica, Hospital General, Centro Médico Nacional La Raza, Instituto Mexicano del Seguro Social, Distrito Federal, México. minitoxx@gmail.com.
authors.forename: M del Carmen S
authors.initials: Mdel C
authors.lastname: Sánchez-Villegas
authors.forename: Astrid
authors.initials: A
authors.lastname: Cortés-Vargas
authors.forename: Ricardo Gerardo
authors.initials: RG
authors.lastname: Hidalgo-Luna
authors.forename: David Abraham
authors.initials: DA
authors.lastname: Alam-Escamilla
authors.forename: Víctor Manuel
authors.initials: VM
authors.lastname: Vargas-García
authors.forename: Jorge
authors.initials: J
authors.lastname: Loría-Castellanos
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000097:blood / Q000209:etiology* / Q000652:urine; D015415:Biomarkers / Q000097:blood / Q000652:urine; D002648:Child; D002675:Child, Preschool; D004781:Environmental Exposure / Q000009:adverse effects* / Q000032:analysis; D004785:Environmental Pollutants / Q000009:adverse effects* / Q000097:blood / Q000652:urine; D005260:Female; D006801:Humans; D007854:Lead / Q000009:adverse effects* / Q000097:blood / Q000652:urine; D008297:Male; D008800:Mexico; D012307:Risk Factors
chemical_list: D015415:Biomarkers; D004785:Environmental Pollutants; D007854:Lead
keywords: Attention deficit disorder with hyperactivity; Child; Lead; Toxicology