A Perspective of Immunologists in Thrombotic Microangiopathies

摘要

Objectives: Aim of this work To understand the immunological bases of Thrombotic microangiopathy syndromes and their implications in diagnosis and therapy. Data Sources: Medline databases (PubMed, Medscape, Science Direct ) and all materials available in the Internet from 2009 to 2017. Article Selection: The article studied. if the articles did not fulfill the inclusion criteria they were excluded. Data Extraction: If the studies did not fulfill the inclusion criteria, they were excluded . Study quality assessment included whether ethical approval was gained, eligibility criteria specified, appropriate controls, adequate information and defined assessment measures. Data Synthesis: Short reviews were made on thrombotic microangiopathy Syndromes. Findings: In total 63 potentially relevant publications were included, 37 were about immnuo-pathogenesis of thrombotic microangiopathy.26 were about immune –based diagnosis and therapy of thrombotic microangiopathy. Conclusion : The immune system plays an important role in the pathogenesis of thrombotic Microangiopathies, either through aberrant complement activation, or through autoantidodies formation. In thrombotic thrombocytopenic purpura, Complement can be activated through anti-ADAMTS13 antibodies immune complexes, or infected or damaged cells . New ADAMTS13 autoantibody testing has prognostic values and also differentiates acquired TTP from rare cases of hereditary TTP. Plasma exchange replenish ADAMTS-13 and remove the ultra-large Von Wellibrand Factor and ADAMTS-13 autoantibodies. Adjunctive immunosuppressive therapy as humanized anti-CD20 monoclonal antibody (Rituximab) with plasma exchange produced good response in patients with refractory or relapsing acquired TTP, also Adjuvant treatment with intravenous immunoglobulin (IVIG) potentiate remission. In Shiga-toxin-induced HUS, it is thought that complement is activated via p-selectin, The atypial Hemolytic Ueramic Syndrome results from aberrant complement alternative pathway activation secondary to mutation in CFH, CFI, CD46, THBD, CFB and C3 genes or anti-FH antibodies. A recent study has confirmed C3 reduction in severe cases of shigatoxin Ecoli-HUS, also Low levels of C4 have also been observed. Eculizumab ( anti-C5) is recommended for cases of aHUS.