Question

Mr. Elder Lee, age 86, is admitted for a hip replacement. His H&H upon admission is 9.0 g/dl and 28%. The doctor wants two units crossmatched and held for a possible transfusion. You receive his properly labeled specimen and proceed with the crossmatch. Here are your findings for the type and screen:

Forward Grouping				Reverse Grouping		Gel Screen
>A	>B	>D	D Control	A1 Cells	B Cells	SCI	SCII	SCIII
0	0	4+	0	0	0	0	0	0

1. What is your interpretation of the forward grouping?

2. What is your interpretation of the reverse grouping?

3. What type of discrepancy do you suspect?

4. Name two ways to resolve the discrepancy.

Answer 1

H&H normal value in adult male is

Hemoglobin: 14-18 g/dl

Hematocrit: 42-52 %

The type and screen test is the compatibility test which is done before transfusion to identify patients ABO blood groups and Rh type.

The major cross match is the final step of pre-transfusion in which the donor’s and recipient’s blood is combined and checked for agglutination.

Type: is the ABO-Rh testing of blood. In which the patient’s blood is mixed with serum and anti –D antibodies to determine anti A ,anti B and Rh respectively.

Screen: (Indirect Coomb’s test) is done to identify most common antibodies in patients blood.

Type and screen reduces the chance of hemolytic reaction to < 1%.

Cross matching again reduce the possibility of hemolytic reaction.

Report ABO type (A, B, or O)followed by D type(+ or -)

1. What is your interpretation of the forward grouping?

Since the anti A , Anti B , Anti D 4+ (positive reaction with D antigen) the group is suggestive of O+

2. What is your interpretation of the reverse grouping?

A1 cell and B1cell is O, it is suggestive of A and B positive

3. What type of discrepancy do you suspect?

When there is disagreement with red cell grouping and serum grouping, ABO discrepancies occur . There is a chance of technical and clinical discrepancy. Or rarely it can be due to clinical condition of the patient. ABO grouping should not be done until the discrepancy is resolved.

In this result the discrepancy can be technical. It should be sorted out and resolved.

In elderly patients a gradual and progressive decrease in anti-A and -B agglutinin titers occurs with age, common in subjects aged 80 years or more.

4. Name two ways to resolve the discrepancy.

Obtain correct patient data

Solving clerical errors by following guidelines.

I.V group discrepancy a=can be eliminated by washing of RBC with warm saline, or use EDTA

Incubation for 30-60 minutes at 37 degree celcius can be done to prevent false positive result of agglutination