Can Anti-Thyroid Antibodies Influence the Outcome of Primary Chronic Immune Thrombocytopenia in Children?

Abstract

Immune thrombocytopenia (ITP) is an acquired immune mediated disorder characterized by isolated thrombocytopenia. Pediatric ITP patients can develop autoantibodies such as anti-thyroglobulin (TG) and anti-thyroperoxidase (TPO), even in the absence of clinical signs of autoimmune disease. The purpose of this article is to provide a review about: 1) the prevalence of positivity of anti-thyroid antibodies (TPO and TG) in pediatric patients with chronic ITP; 2) the role of autoimmune thyroiditis on the outcome of chronic ITP. The authors individually completed a review of the literature for this article. Retrospective and prospective clinical studies with pediatric cohorts were considered. From the analysis of data, we found 4 papers which included studies only on pediatric population, and which corresponded to selected criteria. Pediatric ITP patients have been shown to have a statistically significant prevalence of anti-thyroid antibodies over healthy controls (11.6-36% versus 1.2-1.3%). No correlation has been found between the platelet count and the prevalence of positive anti-thyroid antibodies at any time of the follow up. The results of our bibliographic research demonstrated that: a) pediatric patients with chronic ITP tend to have a statistically significant prevalence of anti-thyroid antibodies positivity respect to general pediatric population; b) there are no clear data about the role of autoimmune thyroiditis as prognostic factor for chronic course of ITP in pediatric age.