Advances in the knowledge of inherited thrombocytopenias (ITs) achieved since the beginning of this century have changed our view of these disorders, as it has become clear that reduced platelet count is not the only clinical issue of affected subjects1. In fact, patients with ITs can not only present with a number of other congenital defects, but also have the predisposition to acquire additional severe haematologic diseases, such as leukaemia or bone marrow aplasia, or extra-haematologic disorders1. For example, patients with MYH9-related disease (MYH9-RD), the most frequent form of IT, are predisposed to develop kidney failure, deafness, juvenile cataracts, and alteration of liver enzymes1, 2. Recent reports prompted the hypothesis that extramedullary haematopoiesis (EMH) could be another acquired manifestation of ITs3, 4. Here, we report a patient with MYH9-RD and massive splenic EMH complicated by spontaneous splenic rupture.