title: Laboratory markers of thrombosis risk in children with hereditary spherocytosis.
abstract: BACKGROUND
  Recent data suggest that adults with hereditary spherocytosis (HS) may be protected from atherothrombosis before splenectomy but have increased risk of thrombosis following splenectomy. In order to aid in making informed decisions regarding splenectomy in children with HS, we conducted a retrospective study of several surrogate laboratory markers of thrombosis risk in children with HS.
  
  
  METHODS
  A retrospective record review was performed on 246 children with HS. Platelet count and hemoglobin concentration were recorded prior to and following splenectomy in each patient. Serum cholesterol levels were collected from the record when available.
  
  
  RESULTS
  Prior to splenectomy, hypocholesterolemia was common. Mean platelet counts in 31 evaluable patients pre- and post-splenectomy were 334 and 608 x 10(9)/L, respectively (P < 0.001). Twenty-nine patients (94%) exhibited persistent thrombocytosis following splenectomy. Hemoglobin values following splenectomy often rose to higher than age and gender-matched norms, with 30% of measurements greater than the 90th percentile and 17% greater than the 97th percentile.
  
  
  CONCLUSIONS
  The findings of hypocholesterolemia before splenectomy and thrombocytosis and mild polycythemia afterwards support the hypothesis that patients with HS might be protected from thrombosis before splenectomy and/or more susceptible afterwards. Prospective studies of additional prothrombotic biomarkers and thrombotic events in HS patients are warranted.
authors.affiliation: Division of Hematology-Oncology, Department of Pediatrics, University of Texas Southwestern Medical Center, Dallas, Texas 75390-9063, USA.
authors.forename: Sarah B
authors.initials: SB
authors.lastname: Troendle
authors.forename: Leah
authors.initials: L
authors.lastname: Adix
authors.forename: Shelley E
authors.initials: SE
authors.lastname: Crary
authors.forename: George R
authors.initials: GR
authors.lastname: Buchanan
mesh_terms: D000293:Adolescent; D015415:Biomarkers / Q000097:blood; D002648:Child; D002675:Child, Preschool; D002784:Cholesterol / Q000097:blood*; D016208:Databases, Factual; D006454:Hemoglobins / Q000032:analysis*; D006801:Humans; D007223:Infant; D007231:Infant, Newborn; D008297:Male; D010976:Platelet Count; D011086:Polycythemia / Q000097:blood / Q000209:etiology; D012189:Retrospective Studies; D012307:Risk Factors; D013103:Spherocytosis, Hereditary / Q000097:blood* / Q000150:complications / Q000601:surgery; D013156:Splenectomy; D013922:Thrombocytosis / Q000097:blood / Q000209:etiology; D013927:Thrombosis / Q000097:blood* / Q000209:etiology
chemical_list: D015415:Biomarkers; D006454:Hemoglobins; D002784:Cholesterol