title: Etiology and incidence of thrombotic and hemorrhagic disorders in Thai patients with extreme thrombocytosis.
abstract: A retrospective study of 126 patients with extreme thrombocytosis (defined as a platelet count > or = 1,000 x 10(9)/L) was performed during a five-year period (June 1994-June 1999). The aim of this study was to determine the etiology and to evaluate the clinical consequences of extreme thrombocytosis. Seventy patients (55.5%) had reactive thrombocytosis (RT) with an age range of 43 +/- 2.2 years, 56 (44.5%) had chronic myeloproliferative disorders (MPD) with an age range of 53 +/- 2.4 years. Underlying causes of RT were malignancy (25/70 or 35.7%), infection (16/70 or 22.9%), postsplenectomized beta-thalassemia/Hb E (11/70 or 15.7%), inflammation (12/70 or 17.1%), iron deficiency anemia (6/70 or 8.6%). Duration post splenectomy in our beta-thalassemia/Hb E patients ranged from 4 months to 21 years, with a median of 10 years. Subtypes of our MPD cases were chronic myeloid leukemia (30/56 or 53.6%), essential thrombocytosis (18/56 or 32.1%), polycythemia vera (4/56 or 7.1%), agnogenic myeloid metaplasia (3/56 or 5.4%) and unclassified MPD (1/56 or 1.8%). Bleeding and thrombotic tendency were respectively noted in 7 (12.5%) and 2 (3.6%) of MPD patients. Two patients of the MPD group (3.6%) experienced both bleeding and thrombotic episodes. One patient (1.4%) of the RT group developed vasculitis-associated thrombosis. However, none of the patients in the RT group had bleeding complications. Extreme thrombocytosis was not a rare condition in a university hospital population, and bleeding and/or thrombotic complication was more common in the MPD group.
authors.affiliation: Department of Medicine, Faculty of Medicine, Ramathibodi Hospital, Mahidol University, Bangkok, Thailand.
authors.forename: S
authors.initials: S
authors.lastname: Chuncharunee
authors.forename: N
authors.initials: N
authors.lastname: Archararit
authors.forename: A
authors.initials: A
authors.lastname: Ungkanont
authors.forename: S
authors.initials: S
authors.lastname: Jootar
authors.forename: P
authors.initials: P
authors.lastname: Angchaisuksiri
authors.forename: A
authors.initials: A
authors.lastname: Bunyaratavej
authors.forename: S
authors.initials: S
authors.lastname: Rojanasthein
authors.forename: V
authors.initials: V
authors.lastname: Atichartakarn
mesh_terms: D000328:Adult; D000368:Aged; D005260:Female; D006470:Hemorrhage / Q000150:complications* / Q000175:diagnosis; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D012189:Retrospective Studies; D012307:Risk Factors; D012720:Severity of Illness Index; D013785:Thailand / Q000453:epidemiology; D013922:Thrombocytosis / Q000453:epidemiology / Q000209:etiology*; D013927:Thrombosis / Q000150:complications* / Q000175:diagnosis; D017086:beta-Thalassemia / Q000150:complications / Q000175:diagnosis