All issues > Volume 51(11); 2008

Original Article

Korean J Pediatr. 2008;51(11):1217-1221. Published online November 15, 2008.

Prevalence and clinical significance of the positive antinuclear antibody in children with idiopathic thrombocytopenic purpura

So Eun SE Jun¹, Seong Sik SS Park¹, Young Tak YT Lim¹

¹Department of Pediatrics, Pusan National University College of Medicine, Busan, Korea

Correspondence Young Tak YT Lim ,Email: limyt@pusan.ac.kr

Abstract

Purpose
: An association between idiopathic thrombocytopenic purpura (ITP) and systemic lupus erythematosus (SLE) has been recognized for decades because thrombocytopenia is the first manifestation in some patients with SLE. However, the risk of later development of SLE in childhood ITP is currently unknown. We retrospectively evaluated the incidence and clinical significance of the positive antinuclear antibody (ANA) in children with acute ITP.
Methods
: This study was retrospectively performed to review the clinical and laboratory characteristics in 77 children diagnosed to have acute ITP and admitted to the Pusan National University Hospital between January 2003 and December 2006. Patients tested positive for ANA were regularly followed-up for at least 12 months for symptoms indicative of SLE.
Results
: Seventy-seven children were included in the study; 38 males (49.4%) and 39 females (50.5%), the mean age was 4.5 years. Sixteen (20.8%) ITP patients had a positive ANA, with a median titer of 1:320. The mean age of the patients with positive ANA was 9.3 years, which is much older than 3.3 years for patients with negative ANA (P<0.05). The positive ANA group was predominantly female (81.3%) compared to the negative ANA group (P<0.05). There was no statistically significant difference in mean platelet counts between both groups. No statistically significant difference was found in ANA positivity and progression to chronic ITP or SLE. After the median follow-up of 32 months, SLE was diagnosed only in one ITP patient with positive ANA.
Conclusion
: Our data demonstrated that ANA positivity is often found in children with acute ITP. Large-scale studies should be considered to determine the significance of ANA positivity in childhood ITP for the later development of SLE.

Keywords :Idiopathic thrombocytopenic purpura, Antinuclear antibody, Systemic lupus erythematosus