What does the warm/cold differentiator mean in Autoimmune haemolytic anaemia?

according to at what temperature the antibodies best cause haemolysis

What are the general features of haemolytic anaemia? (seen in bloods)

• anaemia
• reticulocytosis
• low haptoglobin
• raised lactate dehydrogenase (LDH) and indirect bilirubin
• blood film: spherocytes and reticulocytes

What does the direct antiglobulin test (DAT) detect?

if antibodies or complement system factors have bound to RBCs surface antigens

What's the utility of the antiglobulin test (DAT)?

to sort hemolysis into an immune or nonimmune etiology

Is warm or cold Autoimmune haemolytic anaemia more common?

warm

What are causes of warm Autoimmune haemolytic anaemia?

• idiopathic
• autoimmune disease: e.g. systemic lupus erythematosus*
• neoplasia
• drugs: e.g. methyldopa

What is management of warm Autoimmune haemolytic anaemia?

• treatment of any underlying disorder
• steroids (+/- rituximab) are generally used first-line

What are the causes of cold Autoimmune haemolytic anaemia?

• neoplasia: e.g. lymphoma
• infections: e.g. mycoplasma, EBV

The antibody in cold AIHA is usually {{c1::IgM}} and causes haemolysis best at {{c2::4}} deg C

How does management differ between warm/cold Autoimmune haemolytic anaemia?

Patients respond less well to steroids in cold