Clinical characteristics and outcomes of adult patients with acquired thrombotic thrombocytopenic purpura: a single center retrospective study.

ABSTRACT

BACKGROUND: Thrombotic thrombocytopenic purpura (TTP) is a rare disease and a potentially life-threatening thrombotic microangiopathy. Although the diagnostic and therapeutic techniques have improved, it is still difficult for clinicians to identify early due to different initial clinical manifestations and the incidence and survival rate are reported inconsistently. This study investigated the clinical characteristics, treatment strategies, and treatment outcomes of adult patients with acquired TTP. METHODS: A retrospective analysis of 55 patients (35 females and 20 males) treated for acquired TTP from January 1, 2013 to December 31, 2017 was conducted. The analysis included clinical manifestations at onset, treatment efficacy measures, survival, cause of death, and the APACHE II (Acute Physiology and Chronic Health Evaluation II) and SOFA (sequential organ failure assessment) scores. RESULTS: At onset, in addition to thrombocytopenia and hemolysis, 50 patients (90.91%) presented with neurological abnormalities, but only 19 (34.55%) showed the classic TTP pentad of symptoms. The overall mortality rate was 34.55%. Plasma exchange (PEX) was performed in 49 patients. The most effective treatment was PEX with a normal dose of corticosteroid and rituximab which showed a response rate of 81.25%. The main cause of death was cerebral hemorrhage. The APACHE II and SOFA scores were higher in non-survivors compared to survivors (APACHE II 20.12±7.83 vs. 11.50±4.49, P<0.05; SOFA 12.06±3.27 vs. 7.74±2.10, P<0.05). Non-survivors had higher levels of lactic dehydrogenase (LDH; 1,646.94±1,269.48 vs. 942.76±740.58 IU/L, P=0.015), and higher numbers of schistocytes (6.18%±4.69% vs. 3.44%±3.13%, P=0.035) compared to survivors. CONCLUSIONS: TTP progressed rapidly, and its clinical manifestations varied between patients. The diagnosis depended on the clinical features and laboratory tests. Combination therapy with PEX, immunosuppressive therapy, and rituximab may be useful. Higher APACHE II and SOFA scores, higher LDH levels, and a greater degree of schistocytosis were associated with the severity and outcome of TTP.