Table of Contents
What causes ADAMTS13 deficiency?
ADAMTS13 deficiency can be acquired or congenital Secondary (23 to 67 percent of cases), arising from a variety of conditions, including autoimmune disorders, solid organ or hematopoietic cell transplant, malignancy, drugs and pregnancy.
What type of disorder is TTP?
Thrombotic thrombocytopenic purpura (TTP) is a blood disorder in which platelet clumps form in small blood vessels. This leads to a low platelet count (thrombocytopenia).
How do you test for ADAMTS13?
The levels of the ADAMTS13 antigen can be measured by an enzyme-linked immunosorbent assay (ELISA).
What is treatment for TTP?
Medicines used to treat TTP include glucocorticoids, vincristine, rituximab, and cyclosporine A. Sometimes surgery to remove the spleen (an organ in the abdomen) is needed. This is because cells in the spleen make the antibodies that block ADAMTS13 enzyme activity.
What level of TTP is ADAMTS13?
An ADAMTS13 activity level of less than 10% supports the diagnosis of TTP in appropriate clinical contexts, but many centers do not offer testing in-house and must send out the test to a reference laboratory with a turnaround time of several days.
What is a normal ADAMTS13 level?
The normal range for ADAMTS13 ranges widely depending upon the method by which the assay is performed. In general the normal range lies between 50-160% derived from healthy individuals.
What is the ADAMTS13 test?
Tests for ADAMTS13 Antibodies ADAMTS13 autoantibody testing also differentiates acquired TTP from rare cases of hereditary TTP caused by ADAMTS13 mutations (Upshaw-Schulman syndrome). ADAMTS13 Bethesda assays detect antibodies that neutralize function, which are present in approximately two-thirds of TTP cases.
What is ADAMTS13 level?
An ADAMTS13 activity level greater than 10% (the diagnosis threshold for severe deficiency) does not completely exclude clinical diagnosis of TTP. As many as 40% of patients with clinically diagnosed TTP have ADAMTS13 levels greater than 10%.
What does ADAMTS13 test for?
ADAMTS13 test distinguishes thrombotic thrombocytopenic purpura (TTP) from other thrombotic microangiopathies (TMAs). PLASMIC score helps determine the pretest probability of ADAMTS13 deficiency.