INTRODUCTION
Thrombotic thrombocytopenic purpura (TTP) is a thrombotic
microangiopathy caused by reduced activity of the von Willebrand factor
(VWF) - cleaving protease ADAMTS13. TTP can be acquired, due to an
autoantibody inhibitor, or hereditary, due to inherited variant in the
ADAMTS13 gene [1]. Over 95% of cases are attributable to
acquired autoimmune TTP [2]. Acquired TTP is very rare in children,
the incidence is approximately 30-fold less common than in adults
[3]. TTP can be life-threatening and 34% of patients present a
relapsing disease [4]. Several therapies are available for treatment
of TTP, including plasma exchange (PEX) and immunosuppressive agents
[5,6,7]. Recently, Caplacizumab has been approved for the treatment
of the TTP in the adult population [8, 9,10]. Despite increasing
knowledge on the pathogenesis of TTP in the last years, the therapeutic
approach varies significantly, due to the lack of high-quality evidence
to support strong recommendations [11]. Moreover, no guidelines or
clinical trials for the pediatric population are available at present
day.