title: Thrombopoietin levels in HIV-associated thrombocytopenia in children.
abstract: OBJECTIVE
  To determine the mechanism of human immunodeficiency virus (HIV)-associated thrombocytopenia by using thrombopoietin (TPO) levels.
  
  
  METHODS
  TPO levels were measured in 14 HIV+ children with thrombocytopenia (TCP+), 28 HIV+ children without thrombocytopenia (TCP-), and 15 matched control subjects.
  
  
  RESULTS
  For the patients with moderate symptoms, TPO levels were similar for the TCP+ and TCP- groups (251 pg/mL vs 263 pg/mL; P =.98) and similar to those of control subjects. For the patients with severe symptoms, TPO levels were significantly higher for the TCP+ group versus the TCP- group (1172 pg/mL vs 222 pg/mL; P =.03). Patients with severe symptoms and thrombocytopenia had significantly higher TPO levels than those with moderate symptoms and thrombocytopenia (P <.005), were more likely to require growth factors, and did not respond to treatment with intravenous immunoglobulin.
  
  
  CONCLUSIONS
  TPO levels can distinguish 2 groups of patients with HIV-associated thrombocytopenia. Patients with severe disease had elevated TPO levels, did not respond to treatment with intravenous immunoglobulin, and were more likely to be growth factor-dependent, suggesting marrow failure.
authors.affiliation: Departments of Hematology/Oncology and Special Immunology, Children's National Medical Center, Department of Pediatrics, George Washington University School of Medicine, Washington, DC, USA.
authors.forename: G
authors.initials: G
authors.lastname: Young
authors.forename: B J
authors.initials: BJ
authors.lastname: Loechelt
authors.forename: T A
authors.initials: TA
authors.lastname: Rakusan
authors.forename: J L
authors.initials: JL
authors.lastname: Nichol
authors.forename: N L
authors.initials: NL
authors.lastname: Luban
mesh_terms: D002648:Child; D002675:Child, Preschool; D005260:Female; D016179:Granulocyte Colony-Stimulating Factor / Q000097:blood; D015658:HIV Infections / Q000150:complications; D006801:Humans; D016756:Immunoglobulins, Intravenous / Q000627:therapeutic use; D008111:Liver Function Tests; D008297:Male; D013921:Thrombocytopenia / Q000097:blood* / Q000150:complications; D013926:Thrombopoietin / Q000097:blood*
chemical_list: D016756:Immunoglobulins, Intravenous; D016179:Granulocyte Colony-Stimulating Factor; D013926:Thrombopoietin