Table 1.
Diagnostic approach to acute thrombotic microangiopathy
| Condition | Diagnostic tests |
|---|---|
| Hemolysis | Hemoglobin, red blood cells, indices |
| Reticulocyte and schistocyte counts | |
| Lactate dehydrogenase, haptoglobin | |
| Direct antiglobin test (DAT; Coombs test) | |
| Thrombocytopenia | Platelet counts; Immature platelet fraction |
| Organ damage | |
| Brain | Imaging: CT scana, perfusion MRIa |
| Electroencephalograma | |
| S100 beta, neuron-specific enolase | |
| Neurocognitive testinga | |
| Kidneys | Serum creatinine, glomerular filtration rate |
| Urine output | |
| Heart | Electrocardiogram |
| Troponin, NT-proBNP | |
| Echocardiography | |
| Lung | Oxygen saturation, gas exchange |
| Imaging: chest x‑ray, high-resolution lung CT scana | |
| Coagulation | Plasmatic coagulation assays |
| Antiphospholipid antibodies | |
| Pancreas | Blood glucose, serum lipase |
| Specific diagnosis | |
| General | Biobanking, sampling for possible clinical trials |
| Blood group typing | |
| Pregnancy testa | |
| Tests for viral infections (HIV, hepatitis B and C) | |
| Urine analysis | |
| Thyroid function tests | |
| Thrombotic thrombocytopenic purpura (TTP) | ADAMTS13 activity, antigen |
| Anti-ADAMTS13 antibodies and -inhibitor | |
| VWF:Ag, VWF:activity, VWF:RCo, VWF:CBA, VWF multimeric pattern | |
| ADAMTS13 gene analysis | |
| Hemolytic uremic syndrome (HUS) | Tests for bacterial infection/toxins (E. coli, Shigella, etc) |
| Complement C3 activation products, C4, CH50, APH50, C5a, terminal complement complex, CFH antibody | |
| Complement factors gene analyses | |
| Medical history | Concomitant and previous diseases |
| Underlying conditions (cancer, infections, systemic diseases, transplantation, pregnancy, surgery) | |
| Drugs, medication | |
| Family history | |
CT computerized tomography; MRI magnetic resonance imaging, BNP brain natriuretic peptide; VWF von Willebrand factor; Ag antigen; RCo ristocetin cofactor activity; CBA collagen binding activity; CFH anti-complement factor H; HIV human immunodeficiency virus; ADAMTS13 a disintegrin and metalloproteinase with a thrombospondin type 1 motif, member 13; CH50 total complement activity; APH50 complement alternate pathway 50
aWhen clinically indicated and appropriate