4.11 Immunohematology Problem-Solving Flashcards
Is there a discrepancy between the following blood typing and secretor study results?
Blood typing results: Anti-A Anti-B A1 Cells B Cells
4+ 0 0 4+
Secretor results: Anti-A + saliva + A1 cells = 0
Anti-B + saliva + B cells = 4+
Anti-H + saliva + O cells = 0
A. No problem, the sample is from a group A secretor
B. Blood types as A and saliva types as B
C. Blood types as A, but the secretor study is inconclusive
D. No problem, the sample is from a group A nonsecretor
No problem, the sample is from a group A secretor
What is the best course of action given the following test result? (Assume the patient has not been transfused recently.)
Anti-A Anti-B A1 cells B cells
Mixed field 0 1+ 4+
A. Nothing, typing is normal
B. Type patient cells with anti-A1 lectin and type serum with A2 cells
C. Retype patient cells; type with anti-H and anti-A,B; use screen cells or A2 cells on patient serum; run patient autocontrol
D. Wash patient cells four times with saline; then repeat the forward type
Retype patient cells; type with anti-H and anti-A,B; use screen cells or A2 cells on patient serum; run patient autocontrol
The following results were obtained on a 41-year-old female:
Anti-A Anti-B A1 cells B cells O cells
4+ 0 3+ 4+ 3+
Due to the discrepant reverse grouping, a panel was performed on patient serum
revealing the presence of anti-M. How can the reverse grouping be resolved?
A. Repeat the reverse grouping with a 10-minute incubation at room temperature
B. Repeat the reverse grouping using A1 cells that are negative for M antigen
C. Repeat the reverse grouping using A1 cells that are positive for M antigen
D. No further work is necessary
Repeat the reverse grouping using A1 cells that are negative for M antigen
A 59-year-old male came to the emergency department of a community hospital complaining of dizziness and fatigue. History included no transfusions and a positive rheumatoid factor 1 year ago. His complete blood count (CBC) confirmed anemia. A sample was sent to the blood bank for typing and crossmatching. Upon receipt of the sample in the blood bank, the MLS noticed the ethylenediaminetetraacetic acid (EDTA) sample appeared very viscous. Fearing that the sample would clog the automated instrument, testing was performed by using the tube method. The initial results revealed the following:
Anti-A Anti-B Anti-D Rh Control A1 cells B cells
0 0 4+ 2+ 4+ 4+
The patient’s RBCs were washed eight times with saline, and testing was repeated, giving the following results:
Anti-A Anti-B Anti-D Rh Control A1 cells B cells
0 0 4+ 0 4+ 4+
The antibody screen was negative at the IS, 37°C, and AHG phases; the check cells were positive. Crossmatch testing using two O-positive donor units revealed 1+ at IS, and negative results at the 37°C and AHG phases. The check cells were positive. In light of the crossmatching results, what is the next course of action?
A. Use other donor cells for crossmatching
B. Perform a saline replacement for crossmatching
C. Run the crossmatching test using the Gel system
D. Result the crossmatch as incompatible
Perform a saline replacement for crossmatching
The following results were obtained on a 51-year-old male with hepatitis C:
Anti-A Anti-B Anti-D A1 cells B cells
4+ 4+ 3+ 0 0
What should be done next?
A. Retype the patient’s sample to confirm group AB positive
B. Repeat the Rh typing
C. Run a saline control in forward grouping
D. Report the patient as group AB, Rh positive
Run a saline control in forward grouping
An Rh phenotyping shows the following results:
Anti-D Anti-C Anti-E Anti-c Anti-e
4+ 2+ 0 0 3+
What is the most likely Rh genotype?
A. R1r’
B. R0r
C. R1R1
D. R1r
R1R1
An obstetric patient, 34 weeks pregnant, shows a positive antibody screen at the indirect antiglobulin phase of testing in screening cells I and II; screening cell III was negative. She is group B, Rh negative. This is her first pregnancy. She has no prior history of transfusion. What is the most likely explanation for the positive antibody screen?
A. She has developed an antibody to fetal RBCs
B. She probably does not have antibodies because this is her first pregnancy, and she has not been transfused; check for technical error
C. She received an antenatal dose of RhIg
D. Impossible to determine without further testing
She received an antenatal dose of RhIg
A patient’s serum contains a mixture of antibodies. One of the antibodies is identified as anti-D. Anti-Jka or anti-Fya and possibly another antibody are present. What technique(s) may be helpful to identify the other antibody(s)?
A. Enzyme panel; select cell panel
B. Thiol reagents
C. Lowering the pH and increasing the incubation time
D. Using albumin as an enhancement medium in combination with selective adsorption
Enzyme panel; select cell panel
An anti-M reacts strongly through all phases of testing. Which of the following techniques would not contribute to removing this reactivity so that more clinically significant antibodies may be revealed?
A. Acidifying the serum
B. Prewarmed technique
C. Adsorption with homozygous cells
D. Testing with enzyme-treated RBCs
Acidifying the serum
The reactivity of an unknown antibody could be anti-Jka, but the antibody identification panel does not fit this pattern conclusively. Which of the following would not be effective in determining if the specificity is anti-Jka?
A. Testing with enzyme-treated cells
B. Select panel of homozygous cells
C. Testing with 2-aminoethylisothiouronium bromide (AET)–treated cells
D. Increased incubation time
Testing with 2-aminoethylisothiouronium bromide (AET)–treated cells
A cold-reacting antibody is found in the serum of a recently transfused patient and is suspected to be anti-I. The antibody identification panel shows reactions with all cells at room temperature, including the autocontrol. The reaction strength varies from 2+ to 4+. What procedure would help to distinguish this antibody from other cold-reacting antibodies?
A. Autoadsorption technique
B. Neutralization using saliva
C. Autocontrol using ZZAP reagent-treated cells
D. Reaction with cord blood cells
Reaction with cord blood cells
An antibody identification panel reveals the presence of anti-Leb and a possible second specificity. Saliva from which person would best neutralize the Leb antibody?
Genes
Lewis ABO Secretor
A. Le H sese
B. Le hh Se
C. Le H Se
D. lele hh sese
Le H Se
The automated blood bank analyzer does not detect weak forms of D antigen. Why would running type and screens on the analyzer prevent a patient with a weak D phenotype from forming anti-D?
A. Weak D persons cannot form anti-D
B. The analyzer would show the sample as Rh negative; the patient would receive Rh-negative blood
C. The analyzer would show the sample as Rh positive; the patient would receive Rh-positive blood
D. A and C
The analyzer would show the sample as Rh negative; the patient would receive Rh-negative blood
A cord blood workup was ordered on baby boy Jones. The mother is O negative. Results on the baby are as follows:
Anti-A Anti-B Anti-A, B Anti-D DAT (poly)
4+ 0 4+ 0 2+
The test for weak D on the baby was positive at the AHG phase. Is the mother an RhIg candidate?
A. No, the baby is Rh positive
B. Yes, the baby’s Rh type cannot be determined because of the positive DAT result
C. No, the baby is Rh negative
D. Yes, the mother is Rh negative
Yes, the baby’s Rh type cannot be determined because of the positive DAT result
RBCs from a recently transfused patient were positive on DAT when tested with anti- IgG. Screen cells and a panel performed on a patient’s serum showed very weak reactions with inconclusive results. What procedure could help to identify the antibody?
A. Elution followed by a panel on the eluate
B. Adsorption followed by a panel on the adsorbed serum
C. Enzyme panel
D. Antigen typing the patient’s RBCs
Elution followed by a panel on the eluate
