Quiz: Xenotransfusion in a Cat

The correct answer is B. Transfusion in a cat with a blood type different than its own can result in a potentially fatal hemolytic reaction.^1,2 Type AB is the primary feline blood group system and consists of types A, B, and AB. Cats possess alloantibodies to blood groups not their own (ie, cats with type A blood possess weak antibodies to type B, cats with type B possess strong antibodies to type A, and cats with type AB do not possess alloantibodies; cats with type AB are rare).² Cats have these alloantibodies whether or not they have received a blood transfusion. Cats should always receive type-specific blood, with crossmatching if possible. New feline blood antigens (eg, Mik antigen) that may play a role in donor–recipient compatibility are also being discovered. These discoveries emphasize the importance of crossmatching when available.^1,2

Blood type should not be assumed based on breed. Although exotic cat breeds (eg, Persian, Scottish fold, Abyssinian, Bengal) have a higher incidence of type B blood as compared with domestic shorthair and longhair cats, many of which have type A, some domestic shorthair and longhair cats have type B. A blood-type test should always be performed in cats before a transfusion.³

The correct answer is B. Transfusion in a cat with a blood type different than its own can result in a potentially fatal hemolytic reaction.^1,2 Type AB is the primary feline blood group system and consists of types A, B, and AB. Cats possess alloantibodies to blood groups not their own (ie, cats with type A blood possess weak antibodies to type B, cats with type B possess strong antibodies to type A, and cats with type AB do not possess alloantibodies; cats with type AB are rare).² Cats have these alloantibodies whether or not they have received a blood transfusion. Cats should always receive type-specific blood, with crossmatching if possible. New feline blood antigens (eg, Mik antigen) that may play a role in donor–recipient compatibility are also being discovered. These discoveries emphasize the importance of crossmatching when available.^1,2

Blood type should not be assumed based on breed. Although exotic cat breeds (eg, Persian, Scottish fold, Abyssinian, Bengal) have a higher incidence of type B blood as compared with domestic shorthair and longhair cats, many of which have type A, some domestic shorthair and longhair cats have type B. A blood-type test should always be performed in cats before a transfusion.³

The correct answer is C. Because of the absence of hemoglobin-based oxygen-carrying products in the United States and the patient’s impending cardiopulmonary arrest, xenotransfusion with canine blood should be considered.⁴ This will rapidly provide oxygen-carrying erythrocytes and help stabilize the patient until diagnostics can be performed.⁴ 

Cats with type B blood possess strong anti-A alloantibodies that can cause severe hemolysis and agglutination in the presence of type A blood.³ Infusion of as little as 0.5 mL of type A blood to a cat with type B can result in death, even with administration of diphenhydramine or dexamethasone.³

Although crystalloid fluids can help expand intravascular volume, they do not profoundly improve tissue oxygenation in severely anemic patients. Hazel would likely not survive a 24- to 48-hour wait for type B blood.

Because Hazel is rapidly decompensating, waiting for CBC results can lead to cardiopulmonary arrest and death. Moreover, CBC results are unlikely to change the immediate need for a blood transfusion.

The correct answer is C. Because of the absence of hemoglobin-based oxygen-carrying products in the United States and the patient’s impending cardiopulmonary arrest, xenotransfusion with canine blood should be considered.⁴ This will rapidly provide oxygen-carrying erythrocytes and help stabilize the patient until diagnostics can be performed.⁴ 

Cats with type B blood possess strong anti-A alloantibodies that can cause severe hemolysis and agglutination in the presence of type A blood.³ Infusion of as little as 0.5 mL of type A blood to a cat with type B can result in death, even with administration of diphenhydramine or dexamethasone.³

Although crystalloid fluids can help expand intravascular volume, they do not profoundly improve tissue oxygenation in severely anemic patients. Hazel would likely not survive a 24- to 48-hour wait for type B blood.

Because Hazel is rapidly decompensating, waiting for CBC results can lead to cardiopulmonary arrest and death. Moreover, CBC results are unlikely to change the immediate need for a blood transfusion.

The correct answer is C. Because of the absence of hemoglobin-based oxygen-carrying products in the United States and the patient’s impending cardiopulmonary arrest, xenotransfusion with canine blood should be considered.⁴ This will rapidly provide oxygen-carrying erythrocytes and help stabilize the patient until diagnostics can be performed.⁴ 

Cats with type B blood possess strong anti-A alloantibodies that can cause severe hemolysis and agglutination in the presence of type A blood.³ Infusion of as little as 0.5 mL of type A blood to a cat with type B can result in death, even with administration of diphenhydramine or dexamethasone.³

Although crystalloid fluids can help expand intravascular volume, they do not profoundly improve tissue oxygenation in severely anemic patients. Hazel would likely not survive a 24- to 48-hour wait for type B blood.

Because Hazel is rapidly decompensating, waiting for CBC results can lead to cardiopulmonary arrest and death. Moreover, CBC results are unlikely to change the immediate need for a blood transfusion.

The correct answer is C. Because of the absence of hemoglobin-based oxygen-carrying products in the United States and the patient’s impending cardiopulmonary arrest, xenotransfusion with canine blood should be considered.⁴ This will rapidly provide oxygen-carrying erythrocytes and help stabilize the patient until diagnostics can be performed.⁴ 

Cats with type B blood possess strong anti-A alloantibodies that can cause severe hemolysis and agglutination in the presence of type A blood.³ Infusion of as little as 0.5 mL of type A blood to a cat with type B can result in death, even with administration of diphenhydramine or dexamethasone.³

Although crystalloid fluids can help expand intravascular volume, they do not profoundly improve tissue oxygenation in severely anemic patients. Hazel would likely not survive a 24- to 48-hour wait for type B blood.

Because Hazel is rapidly decompensating, waiting for CBC results can lead to cardiopulmonary arrest and death. Moreover, CBC results are unlikely to change the immediate need for a blood transfusion.

The correct answer is D. Because of the associated adverse effects of a xenotransfusion, this procedure should only be performed in life-threatening situations or when the owner cannot afford to seek referral care.^4,5 It has been suggested that xenotransfusions should be reserved for urgent situations in which the cat is likely to die within 6 hours if no intervention is performed.^4,5

A protocol in which ≥2 clinicians review the details of the case can help minimize unnecessary use of xenotransfusion.⁵ If there is agreement that xenotransfusion is the best treatment, transfusion can be provided. Documented consent, either verbal or written, from the owner is also needed, and the owner should be made aware of potential risks.

The correct answer is D. Because of the associated adverse effects of a xenotransfusion, this procedure should only be performed in life-threatening situations or when the owner cannot afford to seek referral care.^4,5 It has been suggested that xenotransfusions should be reserved for urgent situations in which the cat is likely to die within 6 hours if no intervention is performed.^4,5

A protocol in which ≥2 clinicians review the details of the case can help minimize unnecessary use of xenotransfusion.⁵ If there is agreement that xenotransfusion is the best treatment, transfusion can be provided. Documented consent, either verbal or written, from the owner is also needed, and the owner should be made aware of potential risks.

The correct answer is D. Because of the associated adverse effects of a xenotransfusion, this procedure should only be performed in life-threatening situations or when the owner cannot afford to seek referral care.^4,5 It has been suggested that xenotransfusions should be reserved for urgent situations in which the cat is likely to die within 6 hours if no intervention is performed.^4,5

A protocol in which ≥2 clinicians review the details of the case can help minimize unnecessary use of xenotransfusion.⁵ If there is agreement that xenotransfusion is the best treatment, transfusion can be provided. Documented consent, either verbal or written, from the owner is also needed, and the owner should be made aware of potential risks.

The correct answer is D. Because of the associated adverse effects of a xenotransfusion, this procedure should only be performed in life-threatening situations or when the owner cannot afford to seek referral care.^4,5 It has been suggested that xenotransfusions should be reserved for urgent situations in which the cat is likely to die within 6 hours if no intervention is performed.^4,5

A protocol in which ≥2 clinicians review the details of the case can help minimize unnecessary use of xenotransfusion.⁵ If there is agreement that xenotransfusion is the best treatment, transfusion can be provided. Documented consent, either verbal or written, from the owner is also needed, and the owner should be made aware of potential risks.

The correct answer is C. Xenotransfusion with canine packed RBCs minimizes the feline recipient's exposure to donor plasma. Although canine fresh whole blood supplies oxygen-carrying erythrocytes, there is a higher concentration of donor plasma, which may increase the risk for reaction because of the presence of xenogenic antibodies.² Canine fresh frozen plasma and cryoprecipitate are blood component products that do not contain RBCs. These products are not appropriate in this case because Hazel's primary need is the oxygen-carrying capacity of RBCs.⁴ 

Historically, dogs and cats were not thought to possess alloantibodies against each other; however, recent in vitro studies suggest this may not be true.² In a recent study, cats were not compatible with canine donor RBCs or their plasma, based on the results of major and minor crossmatching.²

The correct answer is C. Xenotransfusion with canine packed RBCs minimizes the feline recipient's exposure to donor plasma. Although canine fresh whole blood supplies oxygen-carrying erythrocytes, there is a higher concentration of donor plasma, which may increase the risk for reaction because of the presence of xenogenic antibodies.² Canine fresh frozen plasma and cryoprecipitate are blood component products that do not contain RBCs. These products are not appropriate in this case because Hazel's primary need is the oxygen-carrying capacity of RBCs.⁴ 

Historically, dogs and cats were not thought to possess alloantibodies against each other; however, recent in vitro studies suggest this may not be true.² In a recent study, cats were not compatible with canine donor RBCs or their plasma, based on the results of major and minor crossmatching.²

The correct answer is C. Xenotransfusion with canine packed RBCs minimizes the feline recipient's exposure to donor plasma. Although canine fresh whole blood supplies oxygen-carrying erythrocytes, there is a higher concentration of donor plasma, which may increase the risk for reaction because of the presence of xenogenic antibodies.² Canine fresh frozen plasma and cryoprecipitate are blood component products that do not contain RBCs. These products are not appropriate in this case because Hazel's primary need is the oxygen-carrying capacity of RBCs.⁴ 

Historically, dogs and cats were not thought to possess alloantibodies against each other; however, recent in vitro studies suggest this may not be true.² In a recent study, cats were not compatible with canine donor RBCs or their plasma, based on the results of major and minor crossmatching.²

The correct answer is C. Xenotransfusion with canine packed RBCs minimizes the feline recipient's exposure to donor plasma. Although canine fresh whole blood supplies oxygen-carrying erythrocytes, there is a higher concentration of donor plasma, which may increase the risk for reaction because of the presence of xenogenic antibodies.² Canine fresh frozen plasma and cryoprecipitate are blood component products that do not contain RBCs. These products are not appropriate in this case because Hazel's primary need is the oxygen-carrying capacity of RBCs.⁴ 

Historically, dogs and cats were not thought to possess alloantibodies against each other; however, recent in vitro studies suggest this may not be true.² In a recent study, cats were not compatible with canine donor RBCs or their plasma, based on the results of major and minor crossmatching.²

The correct answer is D. Although cats initially appear to tolerate a single xenotransfusion (despite evidence that naturally occurring antibodies are present in some cats⁵), a delayed hemolytic reaction is expected to occur as the body begins to recognize the canine erythrocytes as foreign. Hemolysis can occur within 1 day after transfusion, resulting in the canine erythrocyte being undetectable within 3.6 to 6 days post-transfusion.^5,6 Xenotransfusion should not be routinely performed in cats because of naturally occurring antibodies against dog erythrocytes and development of xenogenic antibodies following xenotransfusion.^4,5

The correct answer is D. Although cats initially appear to tolerate a single xenotransfusion (despite evidence that naturally occurring antibodies are present in some cats⁵), a delayed hemolytic reaction is expected to occur as the body begins to recognize the canine erythrocytes as foreign. Hemolysis can occur within 1 day after transfusion, resulting in the canine erythrocyte being undetectable within 3.6 to 6 days post-transfusion.^5,6 Xenotransfusion should not be routinely performed in cats because of naturally occurring antibodies against dog erythrocytes and development of xenogenic antibodies following xenotransfusion.^4,5

The correct answer is D. Although cats initially appear to tolerate a single xenotransfusion (despite evidence that naturally occurring antibodies are present in some cats⁵), a delayed hemolytic reaction is expected to occur as the body begins to recognize the canine erythrocytes as foreign. Hemolysis can occur within 1 day after transfusion, resulting in the canine erythrocyte being undetectable within 3.6 to 6 days post-transfusion.^5,6 Xenotransfusion should not be routinely performed in cats because of naturally occurring antibodies against dog erythrocytes and development of xenogenic antibodies following xenotransfusion.^4,5

The correct answer is D. Although cats initially appear to tolerate a single xenotransfusion (despite evidence that naturally occurring antibodies are present in some cats⁵), a delayed hemolytic reaction is expected to occur as the body begins to recognize the canine erythrocytes as foreign. Hemolysis can occur within 1 day after transfusion, resulting in the canine erythrocyte being undetectable within 3.6 to 6 days post-transfusion.^5,6 Xenotransfusion should not be routinely performed in cats because of naturally occurring antibodies against dog erythrocytes and development of xenogenic antibodies following xenotransfusion.^4,5

The correct answer is C. Feline recipients typically produce antibodies to canine erythrocytes 3 to 5 days postxenotransfusion (some variation is possible).^4,5,7,8 Although a second xenotransfusion can be considered ≤3 to 5 days after the first transfusion, severe reaction is possible if antibodies are present before day 3. In cats given a second xenotransfusion ≥7 days after the initial transfusion, 93.7% show clinical signs of anaphylaxis, and the mortality rate is 66%.^7,9 If a second xenotransfusion is necessary, the authors recommend it be performed ≤3 days after the first xenotransfusion to minimize the risk for reaction. The risks should be discussed with the owner, and repeat xenotransfusion should only be performed as a final option.⁴

The correct answer is C. Feline recipients typically produce antibodies to canine erythrocytes 3 to 5 days postxenotransfusion (some variation is possible).^4,5,7,8 Although a second xenotransfusion can be considered ≤3 to 5 days after the first transfusion, severe reaction is possible if antibodies are present before day 3. In cats given a second xenotransfusion ≥7 days after the initial transfusion, 93.7% show clinical signs of anaphylaxis, and the mortality rate is 66%.^7,9 If a second xenotransfusion is necessary, the authors recommend it be performed ≤3 days after the first xenotransfusion to minimize the risk for reaction. The risks should be discussed with the owner, and repeat xenotransfusion should only be performed as a final option.⁴

The correct answer is C. Feline recipients typically produce antibodies to canine erythrocytes 3 to 5 days postxenotransfusion (some variation is possible).^4,5,7,8 Although a second xenotransfusion can be considered ≤3 to 5 days after the first transfusion, severe reaction is possible if antibodies are present before day 3. In cats given a second xenotransfusion ≥7 days after the initial transfusion, 93.7% show clinical signs of anaphylaxis, and the mortality rate is 66%.^7,9 If a second xenotransfusion is necessary, the authors recommend it be performed ≤3 days after the first xenotransfusion to minimize the risk for reaction. The risks should be discussed with the owner, and repeat xenotransfusion should only be performed as a final option.⁴

The correct answer is C. Feline recipients typically produce antibodies to canine erythrocytes 3 to 5 days postxenotransfusion (some variation is possible).^4,5,7,8 Although a second xenotransfusion can be considered ≤3 to 5 days after the first transfusion, severe reaction is possible if antibodies are present before day 3. In cats given a second xenotransfusion ≥7 days after the initial transfusion, 93.7% show clinical signs of anaphylaxis, and the mortality rate is 66%.^7,9 If a second xenotransfusion is necessary, the authors recommend it be performed ≤3 days after the first xenotransfusion to minimize the risk for reaction. The risks should be discussed with the owner, and repeat xenotransfusion should only be performed as a final option.⁴

The correct answer is B. Once antibodies are produced (≈5-7 days after xenotransfusion), feline recipients must not undergo additional xenotransfusions. It is important that the owner understands and remembers this information, even when central medical records are used. In a study, providing written warning at discharge of the fatal effects of future xenotransfusions helped with owner retention.⁵

The authors found no reports of xenotransfusion inhibiting the recipient from synthesizing its own erythrocytes.

There is a case report documenting transient AB blood type on an immunochromatographic blood typing test following an allogenic A-B mismatched blood transfusion,¹⁰ but this outcome is unlikely and there is no evidence suggesting the patient’s blood type would change after xenotransfusion.

There is no evidence that a recipient of xenotransfusion has an increased chance of transfusion reactions if transfused with type and species-specific blood in the future.

The correct answer is B. Once antibodies are produced (≈5-7 days after xenotransfusion), feline recipients must not undergo additional xenotransfusions. It is important that the owner understands and remembers this information, even when central medical records are used. In a study, providing written warning at discharge of the fatal effects of future xenotransfusions helped with owner retention.⁵

The authors found no reports of xenotransfusion inhibiting the recipient from synthesizing its own erythrocytes.

There is a case report documenting transient AB blood type on an immunochromatographic blood typing test following an allogenic A-B mismatched blood transfusion,¹⁰ but this outcome is unlikely and there is no evidence suggesting the patient’s blood type would change after xenotransfusion.

There is no evidence that a recipient of xenotransfusion has an increased chance of transfusion reactions if transfused with type and species-specific blood in the future.

The correct answer is B. Once antibodies are produced (≈5-7 days after xenotransfusion), feline recipients must not undergo additional xenotransfusions. It is important that the owner understands and remembers this information, even when central medical records are used. In a study, providing written warning at discharge of the fatal effects of future xenotransfusions helped with owner retention.⁵

The authors found no reports of xenotransfusion inhibiting the recipient from synthesizing its own erythrocytes.

There is a case report documenting transient AB blood type on an immunochromatographic blood typing test following an allogenic A-B mismatched blood transfusion,¹⁰ but this outcome is unlikely and there is no evidence suggesting the patient’s blood type would change after xenotransfusion.

There is no evidence that a recipient of xenotransfusion has an increased chance of transfusion reactions if transfused with type and species-specific blood in the future.

The correct answer is B. Once antibodies are produced (≈5-7 days after xenotransfusion), feline recipients must not undergo additional xenotransfusions. It is important that the owner understands and remembers this information, even when central medical records are used. In a study, providing written warning at discharge of the fatal effects of future xenotransfusions helped with owner retention.⁵

The authors found no reports of xenotransfusion inhibiting the recipient from synthesizing its own erythrocytes.

There is a case report documenting transient AB blood type on an immunochromatographic blood typing test following an allogenic A-B mismatched blood transfusion,¹⁰ but this outcome is unlikely and there is no evidence suggesting the patient’s blood type would change after xenotransfusion.

There is no evidence that a recipient of xenotransfusion has an increased chance of transfusion reactions if transfused with type and species-specific blood in the future.

The correct answer is A. Most cats that undergo xenotransfusion experience a delayed hemolytic transfusion reaction that usually happens ≈2 to 7 days postxenotransfusion and is characterized by worsening anemia, icteric serum, and generalized icterus. In a study, 25 out of 39 (64%) cats that had undergone xenotransfusion experienced a delayed hemolytic transfusion reaction,⁵ and 14 out of 39 (≈35%) cats were given a feline type-specific blood transfusion ≈4 days postxenotransfusion. Cats with strongly regenerative anemia may not require another transfusion, as was the case with Hazel.⁵ 

A patient’s requirement for additional transfusions should be monitored in case lysis of the canine erythrocytes occurs faster than the recipient’s regenerative ability. If a repeat transfusion is required in a patient that has previously undergone xenotransfusion, feline type-specific blood should be administered.

The correct answer is A. Most cats that undergo xenotransfusion experience a delayed hemolytic transfusion reaction that usually happens ≈2 to 7 days postxenotransfusion and is characterized by worsening anemia, icteric serum, and generalized icterus. In a study, 25 out of 39 (64%) cats that had undergone xenotransfusion experienced a delayed hemolytic transfusion reaction,⁵ and 14 out of 39 (≈35%) cats were given a feline type-specific blood transfusion ≈4 days postxenotransfusion. Cats with strongly regenerative anemia may not require another transfusion, as was the case with Hazel.⁵ 

A patient’s requirement for additional transfusions should be monitored in case lysis of the canine erythrocytes occurs faster than the recipient’s regenerative ability. If a repeat transfusion is required in a patient that has previously undergone xenotransfusion, feline type-specific blood should be administered.