Flowchart for the identification and treatment of patients with refractory ITP. Ag, antigen; ANA, anti-nuclear antibodies; CMP, comprehensive metabolic panel; CRP; C-reactive protein; CMV, cytomegalovirus; ESR, erythrocyte sedimentation rate; Eval, evaluation; HCV, hepatitis C virus; H pylori, Helicobacter pylori; plt/Plt, platelets; PT, prothrombin time; PTT, partial thromboplastin time; TIBC, total iron binding capacity; Tx, treatment.