ABO ADVANCED COMPREHENSIVE STUDY GUIDE Questions
with Correct Answers (Grade A+)
Question 1: An amsler's grid should be used on a daily basis for patients with_____________.
Answer: Macular degeneration
Question 2: What is an ABO discrepancy?
Answer: An ABO discrepancy is present when there is a disagreement between Rh and ABO typing,
forward and reverse typing, a positive antibody screen, or a positive Direct Antiglobulin Test (DAT).
Question 3: Why must ABO discrepancies be resolved before transfusion?
Answer: ABO discrepancies must be resolved before transfusion because forward and reverse typing
disagreement can lead to unsafe blood selection.
Question 4: Which of the following is used to check for lateral and vertical phorias.
Answer: Maddox rod
Question 5: What is one of the 4 major ABO discrepancy categories?
Answer: One of the 4 major ABO discrepancy categories is 'Missing or weak antigen.'
Question 6: A patient will experience photo phobia and Poor near vision after____________.
Answer: Cycloplegic refraction
Question 7: If the patient says that the green side is clearer during the binocular duochrome test, you
should add_______O U.
Answer: Plus power
Question 8: The physiologic blind spot is located where.
Answer: optic disk
Question 9: What is another major ABO discrepancy category?
Answer: Another major ABO discrepancy category is 'Missing or weak antibody.'
Question 10: What type of discrepancy would a very weak subgroup of A or B most likely cause?
Answer: A very weak subgroup of A or B would most likely cause a 'Missing or weak antigen' discrepancy.
Page 1
,Question 11: What is associated with loss of transferase in acute leukemia?
Answer: Loss of transferase in acute leukemia is associated with 'missing or weak antigen.'
Question 12: The near point of convergence is reached when the test object:.
Answer: Gets so close it blurs
Question 13: When measuring a patient with a horizontal deviation, the Maddox rod should be
positioned so that the line forms a__________.
Answer: Vertical line
Question 14: The instrument that provides information on the patient refractive status by reflecting
light off the retina is_____________.
Answer: Retniscope
Question 15: What may massive transfusion of group O blood cause?
Answer: Massive transfusion of group O blood may cause a 'missing or weak antibody discrepancy.'
Question 16: How may bone marrow transplant contribute to ABO discrepancies?
Answer: Bone marrow transplant may contribute to both 'missing or weak antigen' and 'missing or weak
antibody' discrepancies.
Question 17: What is an appropriate resolution step for a missing or weak antigen discrepancy?
Answer: An appropriate resolution step is to incubate the front type at room temperature or 4-22°C for at
least 15 minutes.
Question 18: Which reagent may react better with some weak A or B subgroups?
Answer: Anti-A1 lectin may react better with some weak A or B subgroups.
Question 19: If a patient misses two letters on the 20/30 acuity line, the acuity should be recorded as.
Answer: 20/30-2
Question 20: What is a cause of missing or weak antibody in reverse typing?
Answer: A cause of missing or weak antibody in reverse typing is advanced age.
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, Question 21: If the patient sees the red side clearer during a monocular duochrome test the focal point
is.
Answer: In front of the retina
Question 22: What ABO discrepancy category does a newborn most likely have?
Answer: A newborn most likely has a 'Missing or weak antibody' discrepancy.
Question 23: What is an appropriate resolution step for missing or weak antibody?
Answer: An appropriate resolution step is to add more serum, up to 4 drops.
Question 24: What should be done if serum is limited during investigation of a missing or weak
antibody discrepancy?
Answer: If serum is limited, it is recommended to use RESt adsorbed plasma.
Question 25: Latent hyperboles and children especially need a ______________.
Answer: Cycloplegic refraction
Question 26: What is a cause of extra antigen in forward typing?
Answer: A cause of extra antigen in forward typing is acquired B.
Question 27: Which of the following conditions could cause change in prescription in an adult patient?
Answer: Diabetes
Question 28: A patient who has a best corrected central acuity of 20/200 is considered ___________.
Answer: legally blind
Question 29: How should cold agglutinin causing extra reactions in forward typing be investigated?
Answer: Cold agglutinin should first be investigated by warm washing patient red cells with 37°C saline.
Question 30: What is the purpose of warm washing patient red cells?
Answer: The purpose of warm washing patient red cells is to disperse cells bound by cold agglutinin.
Question 31: If the patient has a narrow anterior chamber,_____________ pharmaceuticals should be
avoided.
Answer: Mydriatic
Page 3
with Correct Answers (Grade A+)
Question 1: An amsler's grid should be used on a daily basis for patients with_____________.
Answer: Macular degeneration
Question 2: What is an ABO discrepancy?
Answer: An ABO discrepancy is present when there is a disagreement between Rh and ABO typing,
forward and reverse typing, a positive antibody screen, or a positive Direct Antiglobulin Test (DAT).
Question 3: Why must ABO discrepancies be resolved before transfusion?
Answer: ABO discrepancies must be resolved before transfusion because forward and reverse typing
disagreement can lead to unsafe blood selection.
Question 4: Which of the following is used to check for lateral and vertical phorias.
Answer: Maddox rod
Question 5: What is one of the 4 major ABO discrepancy categories?
Answer: One of the 4 major ABO discrepancy categories is 'Missing or weak antigen.'
Question 6: A patient will experience photo phobia and Poor near vision after____________.
Answer: Cycloplegic refraction
Question 7: If the patient says that the green side is clearer during the binocular duochrome test, you
should add_______O U.
Answer: Plus power
Question 8: The physiologic blind spot is located where.
Answer: optic disk
Question 9: What is another major ABO discrepancy category?
Answer: Another major ABO discrepancy category is 'Missing or weak antibody.'
Question 10: What type of discrepancy would a very weak subgroup of A or B most likely cause?
Answer: A very weak subgroup of A or B would most likely cause a 'Missing or weak antigen' discrepancy.
Page 1
,Question 11: What is associated with loss of transferase in acute leukemia?
Answer: Loss of transferase in acute leukemia is associated with 'missing or weak antigen.'
Question 12: The near point of convergence is reached when the test object:.
Answer: Gets so close it blurs
Question 13: When measuring a patient with a horizontal deviation, the Maddox rod should be
positioned so that the line forms a__________.
Answer: Vertical line
Question 14: The instrument that provides information on the patient refractive status by reflecting
light off the retina is_____________.
Answer: Retniscope
Question 15: What may massive transfusion of group O blood cause?
Answer: Massive transfusion of group O blood may cause a 'missing or weak antibody discrepancy.'
Question 16: How may bone marrow transplant contribute to ABO discrepancies?
Answer: Bone marrow transplant may contribute to both 'missing or weak antigen' and 'missing or weak
antibody' discrepancies.
Question 17: What is an appropriate resolution step for a missing or weak antigen discrepancy?
Answer: An appropriate resolution step is to incubate the front type at room temperature or 4-22°C for at
least 15 minutes.
Question 18: Which reagent may react better with some weak A or B subgroups?
Answer: Anti-A1 lectin may react better with some weak A or B subgroups.
Question 19: If a patient misses two letters on the 20/30 acuity line, the acuity should be recorded as.
Answer: 20/30-2
Question 20: What is a cause of missing or weak antibody in reverse typing?
Answer: A cause of missing or weak antibody in reverse typing is advanced age.
Page 2
, Question 21: If the patient sees the red side clearer during a monocular duochrome test the focal point
is.
Answer: In front of the retina
Question 22: What ABO discrepancy category does a newborn most likely have?
Answer: A newborn most likely has a 'Missing or weak antibody' discrepancy.
Question 23: What is an appropriate resolution step for missing or weak antibody?
Answer: An appropriate resolution step is to add more serum, up to 4 drops.
Question 24: What should be done if serum is limited during investigation of a missing or weak
antibody discrepancy?
Answer: If serum is limited, it is recommended to use RESt adsorbed plasma.
Question 25: Latent hyperboles and children especially need a ______________.
Answer: Cycloplegic refraction
Question 26: What is a cause of extra antigen in forward typing?
Answer: A cause of extra antigen in forward typing is acquired B.
Question 27: Which of the following conditions could cause change in prescription in an adult patient?
Answer: Diabetes
Question 28: A patient who has a best corrected central acuity of 20/200 is considered ___________.
Answer: legally blind
Question 29: How should cold agglutinin causing extra reactions in forward typing be investigated?
Answer: Cold agglutinin should first be investigated by warm washing patient red cells with 37°C saline.
Question 30: What is the purpose of warm washing patient red cells?
Answer: The purpose of warm washing patient red cells is to disperse cells bound by cold agglutinin.
Question 31: If the patient has a narrow anterior chamber,_____________ pharmaceuticals should be
avoided.
Answer: Mydriatic
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