Laboratory Findings · bone marrow: appear normal, with a normal or increased number of megakaryocytes · Tests: Coagulation studies will be entirely normal Quantitate platelet-associated IgG may help the diagnosis, highly sensitive(95% but very nonspecific(50%Laboratory Findings • bone marrow： appear normal, with a normal or increased number of megakaryocytes. • Tests： Coagulation studies will be entirely normal. Quantitate platelet-associated IgG may help the diagnosis，highly sensitive (95%) but very nonspecific(50%)