Immune thrombocytopenia in adolescents and evolution to systemic lupus erythematosus: clinical reasoning through the description of three cases

Key words: Thrombocytopenia, Systemic lupus erythematosus, Autoimmunity, Adolescence

Thrombocytopenia, defined by a platelet count lower than 100,000 mm3, in children and adolescents is more frequently ascribable to an immune pathogenesis (Immune Thrombocytopenia, or ITP). ITP is defined “persistent” if it is still present after three months from diagnosis, and “chronic” if remission is not reached after 12 months from the first finding. ITP in childhood usually follows infections of the upper respiratory tract, and presents a self-limiting clinical course, while in adolescents chronic forms are more frequent and require a complex clinical management. The present paper focuses on chronic ITP in adolescents, introducing three cases in which the finding of thrombocytopenia preceded by several years the diagnosis of Systemic Lupus Erythematosus. From the analysis of the presented cases and literature data appears that, even if it is not possible to predict the progression to SLE, patients not responsive to conventional therapies typically developed this condition. Furthermore, the paper suggests an approach that is useful for the confirmation of clinical suspect of ITP and for the surveillance of patients with a high risk of developing the chronic form, in order to identify among them those that will evolve to systemic autoimmune diseases.