TTP – Lab Tests

British Committee for Standards in Haematology clinical practice guideline recommends the following tests in patients with a suspected diagnosis of TTP:

TestComment
Complete blood countAnaemia, thrombocytopenia
Peripheral smearSchistocytes
Reticulocyte countIncreased
HaptoglobinReduced
Clotting screen including fibrinogenNormal
Urea and electrolytes+/- Renal impairment
Troponin T/Troponin IFor cardiac involvement
Liver function testsUsually normal
CalciumMay reduce with TPE
Lactate dehydrogenase (LDH)Increased
Direct antiglobulin testNegative
Blood group and antibody screenTo allow provision of blood products
Pregnancy testIn women of child-bearing age
ADAMTS 13 assay ((activity/antigen and inhibitor/antibody
in specialized laboratory)
Do not wait for result before starting treatment in suspected
TTP
Electrocardiogram/EchocardiogramTo document/monitor cardiac damage
CT/MRI brainTo determine neurological involvement