A Clinico-Epidemiological Study of Childhood Acute and Chronic Idiopathic Thrombocytopenic Purpura

Cho, Young Kuk; Baek, Hee Jo; Lim, Ho Kyung; Kook, Hoon; Ma, Jae Sook; Hwang, Tai Ju

Abstract

PURPOSE
Childhood idiopathic thrombocytopenic purpura (ITP) is an acute, self-limited disease of several weeks, but 10~20% of cases may have chronic courses. This study was aimed to evaluate factors that might predict the progression to chronic ITP. METHODS: Ninty-four patients with ITP were divided into acute and chronic on the basis of disease duration of 6 months. Clinical and laboratory characteristics were compared between the two groups. Response to intravenous immunoglobulin (IVIg) of either 400 mg/kg for 5 days or IVIg 1, 000 mg/kg for 2 days and progression to chronic ITP was compared. RESULTS: 67 cases (71.3%) were acute and 19 (28.7%) were chronic ITP. Sex, preceding viral infection history, clinical manifestations were not significantly different, but acute ITP was more prevalent in less than 1 year of age (P=.001). The initial WBC count was higher in acute than in chronic ITP (9, 600/microL vs. 7, 600/microL) (P < .01), as was initial AST (51 U/L vs. 34 U/L) (P < .05). PCT (platelet hematocrit), MPV (mean platelet volume), PDW (platelet distribution width) of chronic ITP tended to be higher in chronic ITP, but only MPV was significantly different (P < .05). After IVIg infusion, hemoglobin level in acute ITP was significantly decreased (P < .05), and MPV of chronic ITP was significantly increased (P < .05). IVIg 1, 000 mg/kg for 2 days was associated with faster platelet recovery than IVIg 400 mg/kg for 5days (P> .05). The relapse rate and progression to chronic ITP were not different. CONCLUSION: The intial WBC counts, AST, MPV, the changes of hemoglobin level and MPV after IVIg infusion could be useful predictors of developing chronic ITP in children.