Thrombotic thrombocytopenic purpura

It is a rarer disease compared to ITP , but has a serious prognosis.

• Fevers,
• Hemolytic anemia (microangiopathic, schistocytes in blood smear),
• Thrombocytopenia with bleeding manifestations,
• Neurological symptomatology,
• Renal impairment.

Pathogenesis

Idiopathic form

• In the plasma, von Willebrand factor of high molecular weight (as a result of the deficiency of a specific plasma metalloproteinase) with the ability to induce platelet microthrombotization.

Hereditary form

• Mutation of the metalloproteinase gene from the ADAMTS group on chromosome 9,
• In the acquired forms, antibodies against metalloproteinases have been demonstrated,
• In order to cause a TTP attack, the participation of other agents (infection, etc.) is necessary.
• Histologically: multiple hyaline microthrombi in arterioles (central CNS + kidneys).

Secondary thrombotic thrombocytopenic purpura

• In patients after allogeneic transplantation , in systemic diseases, generalized malignancies, after administration of certain drugs (quinine, ticlopidine), complications of intestinal infections.

Clinical course

• severe, violent,
• Patient at risk of ischemia + CNS hemorrhage + renal failure,
• There may be extensive bleeding into the skin ,
• Acute forms with relapses of thrombocytopenia / chronic forms.

Therapy

• Recurrent forms – immunosuppressants (prednisone, cyclophosphamide), rituximab,
• Idiopathic forms – based on administration of fresh frozen plasma + plasmapheresis ,
• Secondary forms – therapy of the underlying disease, discontinuation of suspected drugs,
• Hemolytic uremic syndrome (HUS) = organ limited form of TTP,

• Epidemic form – childhood disease, preceded by enterocolitis ( E. coli ); hemolytic anemia, thrombocytopenia, renal impairment; th.: anti-infective + symptomatic th., or temporary hemodialysis,
• Sporadická forma – intestinal symptomatology is absent, symptoms are more varied; th.: plasmapheresis.

Links

Related articles

• Thrombocytopenia
• Thrombocytopenia of the new born
• Hematological examination
• Pre-transfusion examination
• Examination of blood coagulation
• Purpura

References

• KLENER, P. Vnitřní lékařství. 3. edition. Praha : Galén, 2006. ISBN 80-7262-430-X.