title: Thrombocytosis in illicit drugs-exposed newborns.
abstract: Thrombocytosis in infants exposed in-utero to illicit drugs has been associated to methadone exposure. Although is reported to present in the first two weeks, few studies address its duration and timing of resolution. This study evaluated the presence, duration, and complications of thrombocytosis in newborns exposed to illicit drugs.
  
  
  METHODS
  A retrospective review of medical records of newborns with intrauterine drug exposure admitted to the San Juan City Hospital from 1999 to 2001 was performed.
  
  
  RESULTS
  Thirty-one newborns were included. Eighty-seven percent (87%) presented abstinence syndrome. Of these, 96% presented thrombocytosis. All infants exposed to methadone presented thrombocytosis and 75% of those exposed to heroin and cocaine. Thrombocytosis presented at ten days of life with a median resolution at 26 days.
  
  
  CONCLUSIONS
  In this group of newborns, thrombocytosis was associated to intrauterine exposure to methadone, heroin, and cocaine. Thrombocytosis presented at ten days of life and resolution was seen in three to 4 weeks without complications observed.
authors.affiliation: Department of Pediatrics, San Juan City Hospital, San Juan, Puerto Rico.
authors.forename: Thea
authors.initials: T
authors.lastname: Calderón
authors.forename: Sonia
authors.initials: S
authors.lastname: Medina
authors.forename: Inés
authors.initials: I
authors.lastname: García
authors.forename: Lourdes
authors.initials: L
authors.lastname: García
authors.forename: Marta
authors.initials: M
authors.lastname: Varcárcel
mesh_terms: D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D011247:Pregnancy; D011248:Pregnancy Complications; D012189:Retrospective Studies; D019966:Substance-Related Disorders; D013922:Thrombocytosis / Q000453:epidemiology*