A Comparative Analysis according to Age for Acute Idiopathic Thrombocytopenic Purpura in Children: Especially in Infants under 1 Year of Age

Kwak, Jeong Won; Lim, Young Tak

Abstract

PURPOSE
The age-related clinical expression of acute idiopathic thrombocytopenic purpura (acute ITP) in children is unclear. In particular, information about acute ITP during the first year of life is limited. To find several features distinguishing infants from older children with acute ITP. We evaluated the clinical features, laboratory data, treatment outcomes of childhood acute ITP. METHODS: We retrospectively analysed the data of newly diagnosed 61 children with acute ITP at Pusan National University Hospital between January 1999 and December 2003. RESULTS: The mean age at the diagnosis of childhood acute ITP in our study was 4.7+/-3.9 years of age. In the age groups less than 1, 1~10 and older 10 years there were 14 (23.0%), 37 (60.6%), 10 (16.4%) cases, respectively. Male to female ratio was 1.6 : 1. The mean platelet count at the diagnosis of acute ITP in infants was significantly lower compared to the older age groups (P=0.001). Infants responded favorably to initial intravenous immunoglobulin treatment compared to the older age groups (P < 0.05). In infants, platelet count began to rise rapidly after initial intravenous immunoglobulin treatment. Among the 61 cases who were followed up over 6 months, 14 cases (23.0%) progressed to chronic ITP. Chronic ITP was seen significantly less frequently in infants (7.4%) than other age groups (P < 0.05). CONCLUSION: Infants with acute ITP tend to respond favorably to initial intravenous immunoglobulin treatment. Also, they are less likely to develop chronic ITP compared to the older children.