title: [Perinatal transmission of hepatitis C virus - Santo André Hospital, Leiria 2002-2006].
abstract: BACKGROUND
  Vertical transmission of hepatitis C virus (HCV) is the main route of infection in children, occurring in few cases (five percent). Current recommendations for HCV screening include first anti-HCV testing at age > 18 months, reducing false positives and false negatives. Positive results must be confirmed by the presence of HCV RNA on two different occasions.
  
  
  OBJECTIVE
  To characterize the population of children born to HCV-positive mothers, to identify risk factors for perinatal HCV transmission and to improve the approach to HCV screening.
  
  
  METHODS
  The study was conducted in two phases. An analytic retrospective study enrolling children born to HCV-positive mothers between January 2002 and December 2006 was done, followed by a transversal analysis in order to repeat anti-HCV testing, in cases that didn't meet current recommendations for HCV screening and in those without any HCV screening.
  
  
  RESULTS
  Fifty-nine children born to HCV-positive mothers in a total of 12 985 births were included, corresponding to a prevalence of 0,45%. A high rate of inadequate pregnancy surveillance, prematurity and low birth weight, mainly in children born to addicted mothers was found. A child with HCV infection without any risk factor for perinatal transmission was found. Among children with negative anti-HCV at age 18 months, half had done anti-HCV prior to nine months of age, all were positive. Children discharged because of negative anti-HCV at nine months of age were called in a second phase of the study, for new anti-HCV at age > 18 months. All were negative.
  
  
  CONCLUSIONS
  Perinatal HCV transmission rate was 2,9%. There was no identified risk factor for perinatal transmission in the single case of HCV infection. A high rate of prematurity, low birth weight and inadequate surveillance of pregnancy was found, with statistical significance to relation with mother addiction. Regarding anti-HCV at age < 18 months, a high rate of false positives but no false negative results were found. This study has enabled the detection and correction of mistakes in the approach to HCV screening.
authors.affiliation: Serviço de Pediatria, Hospital de Santo André, Leiria.
authors.forename: Sílvia
authors.initials: S
authors.lastname: Bacalhau
authors.forename: Catarina
authors.initials: C
authors.lastname: Timóteo
authors.forename: João
authors.initials: J
authors.lastname: Agro
mesh_terms: D003430:Cross-Sectional Studies; D005260:Female; D006526:Hepatitis C / Q000453:epidemiology* / Q000635:transmission*; D006761:Hospitals; D006801:Humans; D007231:Infant, Newborn; D018445:Infectious Disease Transmission, Vertical / Q000706:statistics & numerical data*; D008297:Male; D011174:Portugal; D012189:Retrospective Studies; D013997:Time Factors