title: Characterization of chronic idiopathic thrombocytopenic purpura in Japanese children: a retrospective multi-center study.
abstract: The objectives of this study are to clarify (1) the difference in demographic and clinical variables at initial presentation between acute and chronic idiopathic thrombocytopenic purpura (ITP), and (2) the prognostic factors of patients with chronic ITP. We conducted a retrospective analysis of 247 children with newly diagnosed ITP between April 1991 and March 2006 who visited one of the 12 hospitals belonging to the Kyoto University Pediatric Hematologic Study Group. 180 and 67 cases were classified as the acute type and as the chronic type, respectively. Older age, higher initial platelet count, positive medical history or concomitant medical diagnosis, the absence of preceding infection or vaccination, and the absence of an increase in immunoglobulin were risk factors for the chronicity. The prognostic factors in chronic ITP were evaluated in 53 patients after excluding patients receiving splenectomy or having insufficient follow-up data. The overall time required for 50% resolution in patients with chronic ITP was approximately 5.6 years. Age at presentation of less than 3 years and higher platelet counts at the time of chronic ITP diagnosis were good prognostic factors. On the other hand, gender, initial platelet counts, and preceding infection or vaccination were not associated with the prognosis.
authors.affiliation: Faculty of Human Life and Environment, Nara Women's University, Kitauoya-nishi Machi, Nara, Japan. mkubota@cc.nara-wu.ac.jp
authors.forename: Masaru
authors.initials: M
authors.lastname: Kubota
authors.forename: Souichi
authors.initials: S
authors.lastname: Adachi
authors.forename: Ikuya
authors.initials: I
authors.lastname: Usami
authors.forename: Masayuki
authors.initials: M
authors.lastname: Okada
authors.forename: Toshiyuki
authors.initials: T
authors.lastname: Kitoh
authors.forename: Mitsutaka
authors.initials: M
authors.lastname: Shiota
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Taniguchi
authors.forename: Akihiko
authors.initials: A
authors.lastname: Tanizawa
authors.forename: Mitsuhiko
authors.initials: M
authors.lastname: Nanbu
authors.forename: Keigo
authors.initials: K
authors.lastname: Hamahata
authors.forename: Hisanori
authors.initials: H
authors.lastname: Fujino
authors.forename: Kousaku
authors.initials: K
authors.lastname: Matsubara
authors.forename: Yoshihiro
authors.initials: Y
authors.lastname: Wakazono
authors.forename: Tatsutoshi
authors.initials: T
authors.lastname: Nakahata
mesh_terms: D000208:Acute Disease; D000293:Adolescent; D044466:Asian People / Q000706:statistics & numerical data*; D002648:Child; D002675:Child, Preschool; D002908:Chronic Disease; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D015994:Incidence; D007223:Infant; D007564:Japan / Q000453:epidemiology; D053208:Kaplan-Meier Estimate; D008297:Male; D011237:Predictive Value of Tests; D011379:Prognosis; D016553:Purpura, Thrombocytopenic, Idiopathic / Q000453:epidemiology* / Q000503:physiopathology*; D012189:Retrospective Studies; D012307:Risk Factors