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Blood Bank Case Study #1 Paul J., a 55-year old man, was admitted with an intestinal obstruction. The following results were recorded by the blood bank technologist: Forward Grouping Anti-A Anti-B Paul J.

4+

Reverse Grouping A1 Cells B Cells

1+

0

4+

Anti-D 3+

Rh Testing D Control 0

Antibody Screen Screening Cell I Autocontrol IS 37 AHG Paul J 0 0 0

Screening Cell II CC 4+

IS 0

37 0

AHG 0

Screening Cell III CC IS 3+ 0

37 AHG 0+ 0

CC IS 37 AHG CC 3+ 0 0 0 4+

Questions: 1. What is Paul’s probable ABO type? Forward typing – AB positive, reverse typing – A group. His probable ABO type is A positive

2. What is the discrepant result in ABO grouping? Weak reaction (1+) in Anti-B (Forward typing)

3. Explain the phenomenon that caused this pattern and briefly describe two processes by which this can occur. Case of Acquired B phenomenon occurs in blood group A patient (usually A1) which is caused by the action of bacterial enzymes (deacetylase) which modifies A sugar (N-acetyl-Dgalactosamine) into D-galactosamine which is similar to the B sugar (D-galactose). This acquired B antigen thus cross-reacts with Anti-B causing discrepancy in the forward typing. This phenomenon occurs mainly in the colon cancer, gram negative sepsis and other diseases of digestive tract. It can occur in vitro or in vivo. In vivo is a transient condition which occurs on red cells having A antigen. In vitro occurs by coating of A or O red cells with lipopolysaccharides from bacteria like E. coli and P. vulgaris

4. What bacteria are commonly involved? Certain strains of E.coli, Clostridium tertium and Proteus vulgaris 1

5. What steps would you take to confirm your suspicions?  Use of different clone of anti-B preferably monoclonal reagent. Do not use ES4 clone.  Secretor studies (only works on actual secretor). Saliva of a person with acquired B does not have B antigen  Autoincubation – reaction of patient’s own anti-B with acquired B red cells show no agglutination  Acidifying Anti-B – when red cells are treated with acetic anhydride, there is no agglutination when tested with anti-B 6. Is the result of the antibody screen useful? Why or why not? As this is a discrepancy of forward typing (antigens in red cells), not the reverse typing, the negative antibody screen does help to rule out the presence of any auto/alloantibodies in this patient. 7. a. Define secretor Secretor is an individual who possess Se gene and secrete ABH-soluble antigens b. What percent of the population are secretors? 78% (80% US population)

c. Assuming he is SeSe, what ABO antigens will be present in Paul’s secretions? A and H antigen (B gene is not there so B antigen is not formed in Paul’s secretions 8. Will Paul’s ABO reactions convert back to normal? If so, when? Yes the ABO reactions will convert back to normal once the causative microbial organism is eliminated from the patient’s body/infection is resolved.

Blood Bank Case Study #2 Lisa N., a 25-year old woman pregnant with her second child, had routine orders for a “type and screen,” with the following results:

Forward Grouping Anti-A Lisa N.

3+

Reverse Grouping Anti-B A1 Cells 0

0

Antibody Screen 2

B Cells

Rh Testing Anti-D

4+

4+

D Control 0

Screening Cell I IS 37 AHG Lisa N. 0 0 0

CC 4+

Screening Cell II Screening Cell III Autocontrol IS 37 AHG CC IS 37 AHG CC IS 37 AHG CC 0 2+ 3+ 0 2+ 3+ 0 0 0 4+

Questions: 1. What is Lisa’s blood type? A positive 2. What would be the interpretation of the antibody screen? Positive (for SCII and III) – unexpected antibodies present in the patient’s serum 3. What immunoglobulin class is the most probable for this antibody? IgG antibodies reacting at 37°C and AHG phase. 4. Is the antibody an alloantibody and/or autoantibody? Can either be ruled out. Explain. It is alloantibody. Autocontrol is negative so autoantibody can be ruled out 5. What detail in the patient history would provide further evidence for your answer to question 4? History of pregnancy (2nd pregnancy), probably sensitized at 1st pregnancy 6. What procedure would the technologist perform next? Antibody identification in patient, phenotyping in both patient and donor and crossmatch with antigen negative donor units. 7. How are antibodies ruled out in the cross-out method of antibody panel interpretation? Explain the procedure in two or three sentences. The reagent cells that show no reactivity in all three phases are only used to cross out the antigens that are positive in the antigram. Ruling out can be done with two homozygous cells or one homozygous cell and two heterozygous cells or three heterozygous cells. This depends on the protocols of the facilities and how they work around it. The antigens that are not ruled out are circled which must be ruled out with further techniques like enzyme treatment/neutralization/selected cells. Suspected antibody is proved with 3 positive cells and 3 negative cells Review Figure 1-1, “Antibody Panel, Case 1-2.” In this case study, antibodies are excluded only if the patient’s serum does not react with panel cells that are homozygous for the antigen.

8. Why are antibodies ruled out only when there is no reaction with homozygous cells? Antibodies like Duffy, Kidd, MNSs and Rhesus blood group system exhibit dosage effect and hence these antibodies if negative with homozygous cells (double dose) can be ruled out. 3

Reaction with heterozygous cells may be weak or may be absent with these antibodies, so homozygous cells are preferred to rule out the antibodies. 9. What antibody(ies) cannot be ruled out by the panel results? c, E, V, Cw, K, Kpa, Jsa, Jka, Lea, S, Lua 10. What is/are the most likely antibody(ies)? Why? The suspected antibody is Anti-c because the pattern of reactivity matches the antigram reaction for >c 11. a. Discuss the 3+3 Rule (Rule of Three) It is used to statistically prove an antibody by using 3 positive cells in the panel that should react - that do and 3 negative cells that should not react – that don’t. b. Do(es) the antibodies(y) you identified in Question 10 meet the 3+3 Rule? Yes, >c meets the 3+3- Rule with Cells 1,2 & 9 for 3+ rule and Cells 3,4 & 5 for 3rule Lisa N. was phenotyped for the following antigens:

Lisa N.

Anti-C 3+

Anti-c 0

Anti-E 2+

Anti-e 2+

Anti-k 3+

12. What is Lisa’s Fisher-Race phenotype? Does Lisa’s antigen phenotype confirm or conflict with your antibody identification? Lisa’s Fisher-Race phenotype – D+C+E+c-e+ (RhD+). It confirms the antibody identification because she is c antigen negative (i.e. homozygous CC) but might have developed Anti-c, may be because of her history of pregnancy. She has E and k antigen in her phenotype which can rule out anti-E and –k. 13. Does the screening cell antigram (see Figure 1-2) confirm or refute your antibody identification? It confirms the antibody identification because Fig. 1-2 antigram also points towards anti-c to be the suspected antibody. >Jkb also resembles the pattern but it is ruled out in Fig. 1-1

14. Which antibodies would you rule out? Using the rule-out panel (see Figure 1-3) which cells will rule out the remaining antibodies? Anti-K, -Jka, -Lea and S needs to be ruled out (Anti-E is ruled out because of her phenotype) For K – cell 2 (another one from fig.1.1) For Jka – cell 3 (another one from fig.1.1) For Lea – cell 7 (another one from fig.1.1) For S – cell 4 and 6 4

15. If Lisa required crossmatching for 3 units, what additional step would be added to the crossmatch procedure? The donor units should be phenotyped and c antigen negative units should be selected for the crossmatch. Considering the Caucasian population, the antigen frequency of >c is 80%. So, 20% are c negative To find 3 compatible units: 20/100 = 3/x or x=15. 15 units can be screened to find 3 compatible units

Blood Bank Case Study #3 Jim S., a 55-year old man, was admitted to the hospital for cardiac bypass surgery. His physician ordered a type and cross match for 5 units. The blood bank technologist recorded the following results: Forward Grouping Anti-A Jim S.

Reverse Grouping Anti-B A1 Cells

0

0

B Cells

Rh Testing Anti-D

4+

3+

4+

D Control 0

Antibody Screen Screening Cell I Autocontrol IS 37 AHG Jim S. 0 0 0

Screening Cell II CC 3+

IS 0

37 2+

AHG 4+

Screening Cell III CC

IS 0

37 AHG 0 0

CC IS 37 AHG CC 3+ 0 0 0 4+

Questions: 1. What is Jim’s blood type?O positive 2. What is your interpretation of the antibody screen?Positive (SCII) – presence of unexpected antibody 3. What immunoglobulin class is/are the antibody(ies)? Explain. IgG antibodies because these are reacting at 37°C and at AHG phase. Review Figure 2-1. In this case study, antibodies are excluded only if the patient’s serum does not react with panel cells that are homozygous for the antigen.

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4. What antibody(ies) cannot be ruled out by the panel results? E, V, Cw, K, Kpa, Jsa and Lua 5. Is any oneantibody in question 3 a perfect match for the panel results? No, the reaction pattern of any of the above mentioned antibodies do not perfectly match the pattern in the antigram panel. 6. What are some possible explanations for the panel results?  Antibodies showing dosage  Presence of multiple antibodies  Antibodies against either high or low-frequency antigens  Sometimes cold-reactive antibodies but in this case, it is not possible because IS is negative 7. What is the most likely explanation for the panel results? Since E is the only antibody that shows dosage, I think the most likely explanation for the panel result is that this patient has multiple antibodies due to the fact that there is a variation in the strength of reactions like 2+, 3+ and 4+ 8. What is/are the most likely antibody(ies)? If we closely look at the pattern of reactions, I think the most likely antibodies are Anti-E and Anti-K (stronger reactions with only K positive cells – 5, 7, 10 and 16 but less stronger reactions with only E positive cells) 9. How would you rule out the remaining antibodies? The remaining antibodies are not clinically significant as they are low frequency antigens and can be ruled out. 10. Explain how the technologist would proceed to find comparable units for crossmatch. Antigen phenotyping can be done for the donor units to find E and K antigen negative units which can be crossmatched to check for compatibility 11. a. Approximately what percentage of units would be compatible? Considering the Caucasian population, the antigen frequency of >E is 30% and >K is 9%. So, 70 X 91 = 6370/100 = 64% chance of finding a compatible unit b. How many units would have to be phenotyped to find 5 compatible units? To find 5 compatible units: 64/100 = 5/x or x=7.8. 8 units can be screened/phenotyped to find 5 compatible units

Blood Bank Case Study #4 Pat L., a 50-year old woman was admitted to the hospital for a hysterectomy. She had been transfused with 2 units of blood the previous year without incident. Her physician sent down

6

orders for a 4 unit crossmatch. Pat was A positive with a negative antibody screen. Four units of A positive were crossmatched by the blood bank technologist and found compatible. The following morning, Pat was transfused with 2 units during surgery. Later that evening, Pat developed a temperature of 101°F and complained of chills. The evening technologist performed a transfusion reaction workup. Clerical Errors No clerical errors were found. Identification of patient and donor where confirmed.

Hemolysis-Urine Hemolysis-Serum DAT

Pretransfusion Specimen None Detected None Detected Negative

Posttransfusion Specimen None Detected None Detected Negative

Antibody Screen-Pretransfusion Screening Cell I Autocontrol IS 37 AHG Pat L. 0 0 0

Screening Cell II CC 3+

IS 0

37 0

AHG 0

Screening Cell III CC IS 3+ 0

37 AHG 0 0

CC IS 37 AHG CC 3+ 0 0 0 2+

Antibody Screen-Posttransfusion Screening Cell I Autocontrol IS 37 AHG Pat L. 0 0 0

Screening Cell II CC 3+

IS 0

37 0

AHG 0

Screening Cell III CC IS 3+ 0

37 AHG 0 0

CC IS 37 AHG CC 3+ 0 0 0 3+

Questions: 1. Do Pat’s laboratory test results indicate any evidence of in vitro hemolysis? Why or why not? No, the lab results do not indicate any evidence of in vitro hemolysis because the pre and post transfusion specimen for serum and urine does not show any hemolysis. Also DAT and antibody screening is negative for both samples. 2. Does Pat have any alloantibodies or autoantibodies? No, Pat does not have any allo/autoantibodies as the post transfusion antibody screen and autocontrol is negative 7

3. Did Pat have a transfusion reaction? If yes, what type of reaction is most likely? Yes she most likely had a febrile non-hemolytic transfusion reaction 4. What symptoms are associated with this condition? Fever/chills, Cyanosis, Cough, Dyspnea, tachycardia, nausea and vomiting 5. Briefly describe two possible causes for this condition. How often does this occur; in other words, in what percentage of transfusions?  Immune mediated due to the presence of preformed HLA antibodies in the patient that reacts against white cells in the blood component causing the release of endogenous pyrogens  Production and release of active cytokines by the white cells in the donor unit during storage of the component Incidence is 0.1%-1% with leukocyte reduction (according to the book – 1-2% per unit transfused) 6. List five questions or bits of information about the patient that are useful when investigating this condition. It is important to investigate on following points:  at least a 1°C rise in temperature and other signs and symptoms  diagnosis (bacteremia or another underlying illness)  drugs/medications taken by the patient  Transfusion history  History of pregnancy

7. a. Is this condition life-threatening? No, it is not life threatening b. What other conditions may present a similar picture early on and must be ruled out? Acute hemolytic transfusion reaction and transfusion related sepsis may present a similar picture and should be ruled out depending the timing of the occurrence of the reaction and the signs and symptoms. 8. How can this be prevented in the future? Prestorageleuko-reduction of red cells and platelets in case transfusion is necessary, can help in preventing the reaction. Also antipyretics administration can prevent it. 9. List two groups of patients who have an increased incidence of this condition. Transplant patients especially with platelet transfusion, patients with history of multiple transfusions and multiparous female patients are prone to have high chances of having these reactions.

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10.If any checks and procedures performed on this patient had been positive, what additional tests may be indicated? If DAT is positive, then elution studies can be done. Plasma hemoglobin, Haptoglobin, Direct and Indirect bilirubin, LDH and urine hemoglobin can be measured as follow-up tests. If discrepancy/hemolysis is found then repeat antibody screen and crossmatch on both the samples. Also bacterial contamination in donor units can be checked by doing gram stain or blood culture.

Blood Bank Case Study #5 Donor I Karen D., a 30-year old female prospective donor, had the following relevant data from her physical examination and medical history: Last Donation: Hemoglobin: Hematocrit: Pulse: Blood Pressure: Weight: Temp:

6 months 12.2g/dL 37% 85 beats/min 150/80 120 99.9°F

She had her ears pierced with a second hole 4 months ago, and she was recovering from a cold. 1.Do any of the values in the physical examination or answers to the questions in her medical history fall outside of the acceptable limits established by American Association of Blood Banks (AABB)? How many? If any, list the value or criteria and the acceptable limit. There are 4 values/factors from her data that seems to be outside the acceptable limits:  Hemoglobin – 12.2g/dL (should be 12.5g/dL)  Hematocrit – 37% (should be 38%)  Temperature – 99.9 (should be 99.5)  Ear piercing – 4 months (should be 12 months)

2. Would Karen be accepted, temporarily deferred or permanently deferred? If deferred for a certain period of time, how long? She would be temporarily deferred because of her history of ear piercing and that would be for 8 months more so that it becomes 12 months and she will have to undergo the same process again – physical examination and medical history. Her hemoglobin and hematocrit should be increased to meet the criteria and her temperature which is little above the criteria may be because of the cold should come down to normal and within the limit. That way she can donate in the future. 9

3. Is the fact that Karen has a cold a reason for temporary deferral? No, it is a not a reason for temporary deferral but if she had really high temperature and she does not feel well on the day of donation and that she had taken medications for it, then her cold could have been a reason for temporary deferral.

Donor II Mike H., a 41-year old male prospective donor, who was a college professor, presented with the following physical examination and medical history: Last Donation: Hemoglobin: Hematocrit: Pulse: Blood Pressure: Weight: Temp:

10 weeks ago 13.4 g/dL 40.2% 78 beats/min 140/88 165 98.8°F

He answered “Yes” to the question: “in the last 12 months, have you had close contact with a person with jaundice or hepatitis?”

4. Do any of the values in the physical examination or answers to the questions in her medical history fall outside of the acceptable limits established by American Association of Blood Banks (AABB)? How many? If any, list the value or criteria and the acceptable limit. The physical examination results seem to meet the criteria of AABB but his admittance of having is a close contact with a person with jaundice or hepatitis in last 12 months might have exposed him to hepatitis. So he would be temporarily deferred for 12 months. 5. What group is considered exempt form the question regarding “close contact with a person with jaundice or hepatitis”? I think medical professionals/personnel like us, doctors or nurses are exempt from the above mentioned question because of the nature of our job which involves working in close proximity with the patients or handling of the potential samples. Upon further questioning, it was determined that mike’s wife had been diagnosed with hepatitis C 3 months ago. 6. Would Mike be accepted, temporarily deferred or permanently deferred? If deferred for a certain period of time, how long? He would be temporarily deferred for 12 months but he has already been in contact for 3 months so he has wait another 9 months to come back for donation. Donor III 10

Heidi M., an 18-year old female prospective donor who was a college freshman, presented with the following physical examination and medical history: Last Donation: Hemoglobin: Hematocrit: Pulse: Blood Pressure: Weight: Temp:

First time donor 13.0 g/dL 39.2% 105 beats/min 130/80 124 98.5°F

She had been taking Acutane (isotretinoin) for acne but had taken her last dose 3 months ago. 7. Do any of the values in the physical examination or answers to the questions in her medical history fall outside of the acceptable limits established by American ...