Comparison Of Efficacy Of Plasma Exchange In Different Types Of Thrombotic Microangiopathy

Background and objectiveThrombotic microangiopathy(TMA)is a disease characterized by microangiopathic hemolytic anemia(MAHA),thrombocytopenia,and microvascular thrombosis.The TMA process begins with pathological damage to the endothelial cells,leading to the formation of fibrin-rich and platelet-rich thrombus in the microcirculation.Platelets are consumed in the thrombus,and part of the thrombus blocks the shearing force of blood vessel formation,resulting in fragmentation of the red blood cells,causing thrombocytopenia and anemia,respectively.TMA is one of the serious complications of systemic lupus erythematosus(SLE).The clinical manifestations of SLE-TMA are usually diverse and can lead to poor prognosis.In the current guidelines,SLE with severe complications(including diffuse alveolar hemorrhage,TMA,antiphospholipid syndrome,cryogulinemia,and central nervous system involvement)is a class II recommendation for plasma exchange.Plasma exchange may be one of the recommended therapies in SLE-TMA patients.In recent years,more and more patients with SLE-TMA have received plasma exchange therapy,but the efficacy is different.To merely prolong the observation period of the efficacy of plasma exchange is not conducive to the revision of the treatment plan,but also significantly increases the occurrence of the medical risks associated with plasma exchange and greatly increases the medical costs of patients.Therefore,how to predict the efficacy of plasma exchange therapy according to the clinical characteristics of patients before receiving plasma exchange therapy and how to determine the observation period of efficacy after plasma exchange therapy for patients with SLE-TMA is of great importance.Unfortunately,current evidence-based medicine and treatment guidelines fail to answer these two questions.Therefore,this study first evaluated the efficacy of plasma exchange therapy in SLE-TMA patients with thrombotic thrombocytopenic purpura(TTP)as a control group.Then,logistics regression was applied to look for relevant factors that may affect the efficacy of plasma exchange before treatment,so as to guide the clinical recommendation of plasma exchange for patients with SLE-TMA and estimate the observation period of efficacy of SLE-TMA.MethodsAccording to the inclusion and exclusion criteria,a total of 63 TMA patients who underwent plasma exchange treatment in the First Affiliated Hospital of Zhengzhou University from January 2018 to December 2020 were included in this study.There were 36 patients with SLE-TMA,including 4 males and 32 females.There were 27 TTP patients,including 8 males and 19 females.The clinical efficacy of plasma exchange was compared between the two groups.The changes of platelet,lactate dehydrogenase(LDH)and the ratio of broken red in peripheral blood smear before and after treatment were compared.The times and the volume of plasma exchange between the two groups were compared in the patients with significant effect and the total effective patients.Logistic regression analysis was performed on patients with SLE-TMA to determine the factors for predicting the efficacy of plasma exchange.Results1.Comparison of index changes before and after treatment in the two groups of patients showed that the changes in the SLE-TMA group,such as platelet count,LDH,and proportion of peripheral blood smears broken red blood cells were lower than those in the TTP group.the therapeutic efficacy of SLE-TMA group was 30.5%,which was lower than that of TTP group(63.0%).The total response rate of SLE-TMA group was 36.1%,lower than that of TTP group(74.1%).2.The times and plasma volume of plasma exchange required for SLE-TMA patients to achieve the clinical efficacy standard were higher than those in TTP group.3.In the SLE-TMA group,we compared total effective patients with non-effective patients,and we found that lower SLEDAI-2000 score and higher LDH level may indicate better efficacy of plasma exchange therapy.Conclusion1.The total response rate of patients with SLE secondary TMA was lower than that of patients with TTP,and the times and the volume of plasma required by plasma exchange for clinical efficacy of patients with SLE secondary TMA were higher than that of patients with TTP.2.In patients with SLE-TMA,lower SLEDAI-2000 score and higher LDH level may lead to better clinical outcome of plasma exchange therapy in patients with SLE-TMA.