Haematology

Kleihauer Test

It is to determine the distribution of fetal Hb in red cells and especially useful in determining the presence of fetal RBC in the maternal circulation.

Principle:
HbF will be able to resist acid elution to a greater extent than normal cells whereas HbA (adult) gets denatured in these conditions. Red cells containing HbF will be deeply stained whereas cells with HbA will give a ghost-like appearance.

Procedure:
1. Fix blood film with 80% ethanol for 5 mins

2. Rinse with distilled water and dry

3. Immerse in elution solution (haematoxylin & ferric chloride) for 20s.

4. Rinse thoroughly with distilled water

5. Counterstain with eosin for 2 mins

6. Rinse with water and dry

7. Examine under microscope

Results:
HbF level should be <0.01% for adult.
-Adult red cells appear as ghost-like pale pink.
-Fetal cells stain densely red.

QC:
A normal adult blood (negative) and cord blood (positive) should be stained together.

Clinical significance:
It is a sensitive procedure which identifies individual cells containing HbF even when few are present, and their detection in the maternal circulation has provided valuable information on the cause of hemolytic disease of the newborn.


Eunice
TG02
0503245C