Quesmed videos (haemolytic anaemia 4)

Question 1

What is cold autoimmune haemolytic anaemia?

Answer 1

A rare autoimmune disorder characterised by the premature destruction of red blood cells (haemolysis).

In this the RBC’s are tagged by antibodies and destroyed by other immune cells.

Antibodies are most active and cause haemolysis at lower temperatures.

Question 2

What immunoglobulin type is most involved in cold autoimmune haemolytic anaemia?

Answer 2

IgM

Question 3

At what temperature range does cold autoimmune haemolytic anaemia mostly occur?

Answer 3

0-10 degrees celsius

Question 4

What are the causes of cold autoimmune haemolytic anaemia?

Answer 4

Idiopathic

Acute: infections e.g. pneumonia, EBV etc.

Chronic: lymphoproliferative malignancies

Question 5

How is cold autoimmune haemolytic anaemia diagnosed?

Answer 5

Positive direct coombes test

Question 6

What is the treatment for cold autoimmune haemolytic anaemia?

Answer 6

No treatment usually

May require plasmapheresis in severe circumstances.

Question 7

What is plasmapheresis?

Answer 7

Plasmapheresis = A method of removing blood from the body by withdrawal, separating it into plasma and cells and then transfusing back into the bloodstream.

It is performed specifically to remove antibodies in autoimmune conditions.

Question 8

What are the difference between indirect and direct Coombes test?

Answer 8

The direct Coombs test detects antibodies that are stuck to the surface of the red blood cells.

The indirect Coombs test detects antibodies that are floating freely in the blood.

Question 9

When is a direct Coombes test used vs when is an indirect Coombes test used?

Answer 9

Direct Coombes test - to identify haemolytic anaemia.

Indirect Coombes test - used only in prenatal testing of pregnant women and in testing blood prior to a transfusion.