The Combination of Tacrolimus and Danazol as the Treatment of Steroid-resistant/Relapse Immune Thrombocytopenia

Inclusion Criteria: * Primary immune thrombocytopenia (ITP); * 18 years older; * Platelet count of less than 30×10\^9/L at enrollment; * Patients who did not achieve a sustained response to treatment with full-dose corticosteroids for a minimum duration of 4 weeks or who relapsed during steroid-tapering or after its discontinuation; * Patients who were receiving other maintenance regimens, primarily corticosteroids, ciclosporin, or mycophenolate mofetil, were also eligible if the dose of treatment had been stable in the past month and the dose was expected to be stable after enrolment and remained unchanged at least for the first 4 weeks of study until initial response was assessed, unless severe adverse events were suspected. Exclusion Criteria: * Secondary ITP (e.g., patients with HIV, HBV, HCV, Helicobacter pylori infection or SLE); * Congestive heart failure, severe arrhythmia; * Nursing or pregnant women; * ALT or AST levels ≥ 3× the upper limit of the normal threshold; * Creatinine or serum bilirubin levels ≥ 1.5× the upper limit; * Active or previous malignancy ; * Patients who had received danazol treatment or did not respond to danazol; * Patients unable to have routine blood tests because of reasons such as insufficient time.