Abstract
Thrombotic thrombocytopenic purpura (TTP) is a clearly defined entity of thrombotic
microangiopathies (TMAs), a heterogeneous group of disorders characterized by microangiopathic
hemolytic anemia with red cell fragmentation, thrombocytopenia, and organ dysfunction
due to disturbed microcirculation. TTP is characterized by a severe deficiency of
ADAMTS13 (a disintegrin and metalloproteinase with a thrombospondin type 1 motif,
member 13), an enzyme responsible for physiological cleavage of von Willebrand factor
(VWF). Organ dysfunction can be severe and life threatening, and immediate start of
appropriate therapy is necessary to avoid permanent damage or death. The therapeutic
options, however, are often limited to symptomatic measures, and are not standardized
or based on high scientific evidence. During the last years, not only considerable
progress has been made in better diagnosis of TTP, but also new therapeutic strategies
have been established. Initial treatment still is based on plasma exchange and symptomatic
measures to protect organ function, but new concepts (immunosuppression, targeted
anti-VWF or anticomplement therapy, and replacement with recombinant enzymes) are
currently under development.
Keywords
thrombotic-thrombocytopenic purpura - thrombotic microangiopathy - ADAMTS13 - platelets
- von Willebrand factor
