title: A three-year follow-up of congenital adrenal hyperplasia newborn screening.
abstract: OBJECTIVE
  congenital adrenal hyperplasia (CAH) newborn screening can prevent neonatal mortality in children with the salt-wasting form of the disease and prevent incorrect gender assignments, which can occur in females. However, the occurrence of false-positive results in preterm or low-birth-weight newborns creates some diagnostic difficulties, with consequent therapeutic implications. This study aimed to report the results of a pilot project for neonatal CAH screening conducted in the state of Minas Gerais, Brazil from 09/2007 to 05/2008 with a three-year follow-up.
  
  
  METHODS
  dried blood specimens were collected on filter paper cards three to seven days after birth of all newborns in the period. Samples were analyzed for 17-hydroxyprogesterone using an enzyme-linked immunosorbent assay (ELISA).
  
  
  RESULTS
  a total of 159,415 children were screened. The apparent incidence of the classic variant of the disease was 1:9,963, based on initial diagnoses following newborn screening. During the follow-up period, eight of 16 children initially diagnosed with CAH were reclassified as unaffected, resulting in a revised incidence of 1:19,927. The false-positive rate was 0.31%, and the positive predictive value was 2.1%. Sensitivity and specificity were 100% and 99.7%, respectively.
  
  
  CONCLUSIONS
  newborn screening is an important public health policy in developing countries such as Brazil, where CAH remains underdiagnosed. It has great potential to identify children with the disease who otherwise cannot be diagnosed earlier. Long-term follow-up and monitoring of all children with positive screening results are crucial to ensure a correct diagnosis and to calculate a reliable incidence ratio of the disease.
authors.affiliation: Department of Pediatrics, Division of Pediatric Endocrinology, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brazil.
authors.forename: Isabela L
authors.initials: IL
authors.lastname: Pezzuti
authors.affiliation: Department of Pediatrics, Division of Pediatric Endocrinology, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brazil.
authors.forename: Cristina B
authors.initials: CB
authors.lastname: Barra
authors.affiliation: Division of Pediatric Endocrinology, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brazil.
authors.forename: Rafael M
authors.initials: RM
authors.lastname: Mantovani
authors.affiliation: Department of Internal Medicine, Núcleo de Ações e Pesquisa em Apoio Diagnóstico (NUPAD), Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brazil.
authors.forename: José N
authors.initials: JN
authors.lastname: Januário
authors.affiliation: Department of Pediatrics, Division of Pediatric Endocrinology, Universidade Federal de Minas Gerais (UFMG), Belo Horizonte, MG, Brazil. Electronic address: ivanins@gmail.com.
authors.forename: Ivani N
authors.initials: IN
authors.lastname: Silva
mesh_terms: D019326:17-alpha-Hydroxyprogesterone / Q000097:blood; D000312:Adrenal Hyperplasia, Congenital / Q000150:complications / Q000175:diagnosis* / Q000453:epidemiology; D001724:Birth Weight; D001938:Brazil / Q000453:epidemiology; D002675:Child, Preschool; D042241:Early Diagnosis; D004797:Enzyme-Linked Immunosorbent Assay; D005189:False Positive Reactions; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D015997:Neonatal Screening / Q000379:methods*; D010865:Pilot Projects; D011237:Predictive Value of Tests; D012680:Sensitivity and Specificity; D014770:Virilism / Q000209:etiology
chemical_list: D019326:17-alpha-Hydroxyprogesterone
keywords: 17-hidroxiprogesterona; 17-hydroxyprogesterone; Congenital Adrenal Hyperplasia; Diagnóstico Precoce; Early Diagnosis; Hiperplasia Adrenal Congênita; Neonatal Screening; Triagem Neonatal