title: Early Reticulocytosis and Anemia Are Associated with Abnormal and Conditional Transcranial Doppler Velocities in Children with Sickle Cell Anemia.
abstract: OBJECTIVE
  To improve prediction of sickle cell anemia severity at an early age, we evaluated whether absolute reticulocyte count (ARC) or hemoglobin (Hb) levels during early infancy (2-6 months of age) in patients with sickle cell anemia predict the risk of later developing an abnormal (abTCD) or conditional (cdTCD) Transcranial Doppler (TCD).
  
  
  METHODS
  We used chart review to identify 121 consecutive patients who underwent TCD screening and had steady state ARC and Hb levels recorded between 2 and 6 months of age. Cox regression analysis was used to determine the relationship between ARC, Hb levels, and risk of developing cdTCD/abTCD over time.
  
  
  RESULTS
  Mean ARC in early infancy was highest and mean Hb lowest in those children with abTCDs and cdTCDs. Cox regression analysis revealed that those subjects with an ARC ≥200 K/μL in early infancy had nearly 3 times the risk of having an abTCD/cdTCD than the group with an ARC <200 K/μL, and patients with a Hb <8.5 g/dL had 2.7 times the risk of having an abTCD/cdTCD.
  
  
  CONCLUSIONS
  These data suggest that both elevated ARC and low baseline Hb during early infancy are associated with an increased risk of developing a cdTCD or abTCD later in childhood.
authors.affiliation: Center for Cancer and Blood Disorders, Children's National Medical Center, Washington, DC; Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC. Electronic address: emeier@ihtc.org.
authors.forename: Emily Riehm
authors.initials: ER
authors.lastname: Meier
authors.affiliation: Center for Cancer and Blood Disorders, Children's National Medical Center, Washington, DC; Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC.
authors.forename: Ross M
authors.initials: RM
authors.lastname: Fasano
authors.affiliation: Center for Cancer and Blood Disorders, Children's National Medical Center, Washington, DC.
authors.forename: Monica
authors.initials: M
authors.lastname: Estrada
authors.affiliation: Division of Biostatistics and Study Methodology, Children's National Medical Center, Washington, DC.
authors.forename: Jianping
authors.initials: J
authors.lastname: He
authors.affiliation: Center for Cancer and Blood Disorders, Children's National Medical Center, Washington, DC; Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC.
authors.forename: Naomi L C
authors.initials: NL
authors.lastname: Luban
authors.affiliation: Department of Pediatrics, The George Washington University School of Medicine and Health Sciences, Washington, DC; Division of Biostatistics and Study Methodology, Children's National Medical Center, Washington, DC.
authors.forename: Robert
authors.initials: R
authors.lastname: McCarter
mesh_terms: D000293:Adolescent; D000367:Age Factors; D000740:Anemia / Q000209:etiology*; D000755:Anemia, Sickle Cell / Q000097:blood* / Q000150:complications*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D011379:Prognosis; D017701:Reticulocyte Count; D045262:Reticulocytosis; D013997:Time Factors; D017585:Ultrasonography, Doppler, Transcranial