Clinical Study of Idiopathic Thrombocytopenic Purpura: Focused on Reticulated Platelet / 대한소아혈액종양학회지

ABSTRACT

PURPOSE: Immune thrombocytopenic purpura (ITP) is divided into acute and chronic forms. Unfortunately, there have been no known specific laboratory or clinical predictors for the diagnosis of chronic ITP. This study was performed to elucidate the prognostic significance of various clinical and laboratory parameters, including reticulated platelet percentage. METHODS: We retrospectively analyzed 60 patients who were diagnosed as ITP at the Department of Pediatrics, Wonju Christian Hospital from January, 1989 to January, 2001. Various kind of clinical parameters such as age, sex, symptom duration, prior URI history, response to treatment, and laboratory parameters like platelet count at initial presentation, lowest platelet count, duration of thrombocytopenia, initial reticulated platelet percentage, antiplatelet antibody IgG and IgM, antinuclear antibody (ANA), direct and indirect Coombs' test were compared between acute and chronic ITP. RESULTS: Fifteen % of patients (9/60) was chronic ITP. The peak age incidence was from 1 to 3 year of age in both acute (29.4%) and chronic ITP (22.2%). The acute ITP was prevalent in spring season, May and June. There was no difference in the incidence of prior URI history between acute and chronic ITP. Higher proportion of chronic ITP patients (5/9; 55.5%) than acute ITP patients (7/51; 13%) had symptom duration longer than 1 month (P or =1 months duration of presenting symptoms and relapse after 2 months from initial presentation have the propensity of developing chronic ITP. Reticulated platelet percentage could not discriminate acute and chronic ITP. A more accurate detection method should be developed for reticulated platelets.