Table 3:

Bloodwork abnormalities in pseudo-thrombotic microangiopathy (TMA) from vitamin B12 deficiency, compared with thrombotic thrombocytopenic purpura (TTP) and disseminated intravascular coagulation (DIC)

Pseudo-TMA from vitamin B12 deficiency (± DIC)TTPDIC
Hemoglobin↓↓
MCV–/↑
Platelets
Leukocytes
Reticulocytes–/↓
Peripheral blood filmHypersegmented neutrophils, schistocytes (few), dacrocytesSchistocytesSchistocytes (few)
INR–/↑
aPTT–/↑
Fibrinogen–/↓
Creatinine–/↑–/↑
Unconjugated bilirubin↑↑
Direct antiglobulin testNegativeNegativeNegative
Lactate dehydrogenase↑↑–/↑
Haptoglobin
d-dimer, ng/mL–/↑↑↑
ADAMTS13, %> 10< 10> 10
Vitamin B12 level↓↓
  • Note: aPTT = activated partial thromboplastin time, ADAMTS13 = a disintegrin and metalloproteinase with thrombospondin motifs 13, INR = international normalized ratio, MCV = mean corpuscular volume.