Naturally occurring antibodies in cats against dog erythrocyte antigens and vice versa

NONDOMESTIC FELID ABC BLOOD PHENOTYPING, GENOTYPING, AND CROSSMATCHING

Based upon previous clinical experience with domestic cats (Felis catus), the ability to assess ABC blood types and blood (in-)compatibilities of nondomestic felids, and adequately consider and plan for blood transfusions, may be important. Although nondomestic felids appear to have an ABC blood group system similar to domestic cats, typing with point-of-care kits and by CMAH genotyping for domestic cats have not been reported. In this study, 162 blood samples from 18 different nondomestic felid species (cheetah [Acinonyx jubatus, n = 42], lion [Panthera leo, n = 33], tiger [Panthera tigris, n = 23], Canada lynx [Lynx canadensis, n = 11], snow leopard [Uncia uncia, n = 10], puma [Puma concolor, n = 7], clouded leopard [Neofelis nebulosa, n = 6], serval [Leptailurus serval, n = 5], jaguar [Panthera onca, n = 5], fishing cat [Prionailurus viverrinus, n = 4], Pallas cat [Felis manul, n = 3], bobcat [Lynx rufus, n = 3], ocelot [Leopardus pardalis, n = 3], black footed cat [Felis nigripes, n = 2], leopard [Panthera pardus, n = 2], African wildcat [Felis lybica, n = 1], caracal [Caracal caracal, n = 1], and sand cat [Felis margarita, n = 1]) were ABC blood typed by laboratory and point-of-care tests, genotyped for four known CMAH variants for type B and type C (AB) phenotypes, and crossmatched with one another and domestic type A cats. Traditional tube typing identified blood type A (n = 106), type B (n = 8), type C (n = 43), and no discernible ABC type (n = 4). Several discrepancies were found between point-of-care and traditional typing test results. None of the tested felids possessed the four CMAH variants responsible for type B and C (AB) in domestic cats. Crossmatch incompatibilities (≥2+ agglutination) were identified within and between nondomestic felid species and beyond ABC incompatibilities. Of 26 crossmatches performed between domestic cats and various nondomestic felids, only 7 (27%) were compatible. In conclusion, point-of-care typing kits and CMAH genotyping, successfully used in domestic cats, may not identify the correct ABC blood type in nondomestic felids. Prior crossmatching is recommended to increase the likelihood of compatible transfusions between any nondomestic felids.

Retrospective study of canine blood xenotransfusion compared with type-matched feline blood allotransfusion to cats: indications, effectiveness, limitations and adverse effects

OBJECTIVES

Xenotransfusion is the transfusion of blood from one species to another. With varying availability of allogenic feline blood (AFB) and in emergency conditions, circumstances occur when canine blood is transfused to cats. This study aimed to characterise the indications, effectiveness, limitations, and acute and late transfusion-related adverse effects of canine blood xenotransfusion compared with matched AFB to anaemic cats, and their survival and longer-term outcome.

METHODS

This retrospective study (2013-2020) examined cats receiving canine blood xenotransfusions or AFB.

RESULTS

The study included 311 cats (xenotransfusion [X-group], n = 105; allotransfusion [A-group], n = 206). Xenotransfusion was more frequent among cats sustaining haemorrhage than in those with haemolysis (P <0.01) or hypoproliferative anaemia (P <0.001). Financial constraints were the most common reason to elect xenotransfusion (49%). The post-transfusion mean packed cell volume was higher (P <0.001) in the X-group (22%) compared with the A-group (18%), and also higher (P <0.001) at 48-96 h post-transfusion (23% vs 18%, respectively). Transfusion-related adverse effects (TRAEs) were more frequent (P = 0.001) in the X-group (37.1%) compared with the A-group (19.4%), as were delayed haemolytic transfusion reactions (85% vs 42.5%, respectively; P <0.001). Acute transfusion reactions (ATRs) were more frequent (P <0.001) in the A-group (60%) compared with the X-group (20%). TRAEs were unassociated with survival to discharge. The survival to discharge rate of the X-group (55%) was lower (P = 0.007) than in the A-group (73%), while post-discharge survival rates to 30 days of cats surviving to discharge were 90% and 88%, respectively (P = 0.85).

CONCLUSIONS AND RELEVANCE

Canine blood xenotransfusions to cats might save lives in emergency conditions when AFB is unavailable or blood typing is infeasible. The survival to discharge rate of the X-group was lower than that of the A-group. The longer-term survival rate of cats administered xenotransfusions and surviving to discharge from the hospital was good.

Incidence of acute haemolysis in cats receiving canine packed red blood cells (xenotransfusions)

OBJECTIVES

The aim of this study was to report the incidence of transfusion reactions in cats, including acute haemolysis (AH), occurring within 24 h of receiving a xenotransfusion. An additional aim was to determine whether cases with AH could be classified as having an acute haemolytic transfusion reaction (AHTR) as per the definition provided by the Association of Veterinary Haematology and Transfusion Medicine's Transfusion Reaction Small Animal Consensus Statement.

METHODS

Medical records of cats that received canine packed red blood cells (PRBCs) between July 2018 and September 2020 at a veterinary hospital were reviewed. The incidence of AH, AHTRs, febrile non-haemolytic transfusion reactions (FNHTRs), transfusion-associated circulatory overload and septic transfusion reactions were recorded.

RESULTS

The medical records of 53 cats were retrospectively evaluated. Twenty-three (43%) cats had transfusion reactions. Thirteen (25%) cats had AH; however, only four (8%) met the definition of an AHTR. Ten (19%) cats were determined to have FNHTRs. Survival to discharge of cats affected by AH was 50% (25% for cases that met the definition of an AHTR). Survival to discharge of cats not suffering from AHTR was 40%.

CONCLUSIONS AND RELEVANCE

This report indicates that a higher proportion of cats undergo AH (25%) when administered canine PRBCs than previously reported, although many could not be classed as having an AHTR due to an apparently adequate packed cell volume rise. Challenges with sourcing feline blood in emergency situations occasionally necessitates the use of xenotransfusion in transfusion medicine. Clinicians should be aware that haemolysis after xenotransfusion can occur within 24 h and that a repeat feline transfusion may be required sooner than anticipated in some cases.

Xenotransfusion of Blood from Dog to Cat: Should Canine Blood Be Our First Choice for Feline Transfusion in Emergency Situations?

Despite the ability to determine feline blood types, the transfusion of canine blood to cats is still practiced in some countries. Xenotransfusion is effective—even if its effects only last for a few days—and is not associated with serious adverse effects. It avoids the need for blood typing, and most importantly, it avoids the transmission of intraspecific infectious agents, notably the feline leukemia virus (FeLV). Transfusion with canine blood is easier, quicker and less costly than transfusion with feline blood; it is less disagreeable for the donor. In the light of these arguments, when feline blood collected according to current guidelines is not available, in particular when the donor is not confirmed to be negative for the FeLV provirus, the authors consider it to be judicious to use canine blood for feline transfusion in emergency situations; this practice is preferable to inaction and to the inoculation of an infectious agent. Allotransfusion remains preferable in non-emergency situations as a treatment of chronic compensated anaemiae or if an appropriate donor (negative for FeLV provirus) is available. However, 2–4 days after a xenotransfusion, if a clinical alteration and a significant decrease in haematocrit are observed, a transfusion with cat’s blood confirmed to be negative for FeLV provirus should be performed. Xenotransfusion should never be used twice.

In vitro compatibility testing of canine and rabbit blood

OBJECTIVE

To determine the in vitro compatibility of rabbit and canine blood using both a tube and slide agglutination crossmatch technique and to compare the results obtained from these 2 methods.

DESIGN

Prospective observational laboratory study from January to March 2020.

SETTING

University veterinary teaching hospital.

ANIMALS

Six client-owned rabbits ≥3.5 kg undergoing phlebotomy for a clinical reason. "Pigtail" blood samples from 3 dog erythrocyte antigen (DEA) 1-positive and 3 DEA 1-negative canine packed red blood cell units.

INTERVENTIONS

Blood from each rabbit was crossmatched with a single unit of canine blood using both a standard laboratory tube agglutination technique and a simple slide agglutination method with each rabbit/canine unit serving as its own intraassay control. Tube crossmatches were evaluated for agglutination both macro- and microscopically and assessed for hemolysis. Slide crossmatches were assessed for the presence of agglutination both macro- and microscopically.  MEASUREMENTS AND MAIN RESULTS: All crossmatches were incompatible. Varying degrees of agglutination were seen for all crossmatches. Hemolysis was observed with all minor tube crossmatches. Results of both crossmatch techniques were in close agreement.  CONCLUSIONS: The crossmatch results in this present study strongly demonstrate in vitro incompatibility between canine and rabbit blood. Agreement between the 2 techniques in this study indicates that the slide agglutination technique may be quicker, require less blood, and provide reliable results in exclusively assessing the compatibility of canine and rabbit blood. Based on the results of this study, emergency xenotransfusion of canine blood to rabbits cannot be recommended.

Association of Veterinary Hematology and Transfusion Medicine (AVHTM) Transfusion Reaction Small Animal Consensus Statement (TRACS) Part 2: Prevention and monitoring

OBJECTIVE

To systematically review available evidence to develop guidelines for the prevention of transfusion reactions and monitoring of transfusion administration in dogs and cats.

DESIGN

Evidence evaluation of the literature (identified through Medline searches through Pubmed and Google Scholar searches) was carried out for identified transfusion reaction types in dogs and cats. Evidence was evaluated using PICO (Population, Intervention, Comparison, Outcome) questions generated for each reaction type. Evidence was categorized by level of evidence (LOE) and quality (Good, Fair, or Poor). Guidelines for prevention and monitoring were generated based on the synthesis of the evidence. Consensus on the final recommendations and a proposed transfusion administration monitoring form was achieved through Delphi-style surveys. Draft recommendations and the monitoring form were made available through veterinary specialty listservs and comments were incorporated.

RESULTS

Twenty-nine guidelines and a transfusion administration monitoring form were formulated from the evidence review with a high degree of consensus CONCLUSIONS: This systematic evidence evaluation process yielded recommended prevention and monitoring guidelines and a proposed transfusion administration form. However, significant knowledge gaps were identified, demonstrating the need for additional research in veterinary transfusion medicine.

The dog erythrocyte antigen 1 blood group in nondomesticated canids and compatibility testing between domestic dog and nondomesticated canid blood

Background

The dog erythrocyte antigen (DEA) 1 blood group is considered as the most immunogenic and clinically important in dogs. Little is known in nondomesticated canids.

Objectives

To type DEA 1 in nondomesticated captive canids and to evaluate potential interspecific blood transfusions between domestic and nondomestic canids.

Animals

One hundred forty captive nondomesticated canids belonging to 13 species from 19 French zoos, and 63 domestic dogs.

Methods

Prospective study. Blood samples were typed for DEA 1 using immunochromatographic and flow cytometric techniques. A neutral gel column test was used for crossmatching.

Results

Of 140 nondomesticated canids, 72.9% were DEA 1+ and 27.1% were DEA 1− using immunochromatographic technique and 74.3% were DEA 1+ and 25.7% were DEA 1− by flow cytometric technique.

Crossmatch (XM) between 140 nondomesticated canid red blood cells (RBCs) and plasma from a previously DEA 1+ sensitized DEA 1− dog revealed 112 incompatibilities (80%). Crossmatches between 130 nondomesticated canid serum and 1 or up to 8 donor dogs' RBCs revealed 99 of 130 (76%) compatibilities. Crossmatches between 115 nondomesticated canid RBCs and donor dogs' serum revealed 59 of 115 (51%) compatibilities.

Conclusions and Clinical Importance

Dog erythrocyte antigen 1 blood type is present in nondomesticated canids with variable prevalence depending on species. The majority of tested nondomesticated canids appear to have no naturally occurring alloantibodies against domestic dogs' RBCs. Therefore xenotransfusion of blood from domestic dogs can be considered when species specific blood is not available. Cross matching is essential before xenotransfusion.

Small Animal Transfusion Medicine

Transfusion medicine can be a lifesaving intervention. Component therapy has expanded the availability and blood products available. Patient safety and minimizing risk is important and can be accomplished through proper donor screening, collection, storage, compatibility testing, administration, and monitoring. The pros and cons of available products must be considered and tailored to each individual patient. Recent discoveries include new antigens and blood types, microbial effects on blood type, and the association between blood type and disease prevalence.

Life-Threatening Hemorrhage During Patent Ductus Arteriosus Ligation in a Cat: Xenotransfusion With Canine Blood

A 13-month-old Sphynx cat was referred for patent ductus arteriosus (PDA) ligation. A left thoracotomy was performed and the PDA was efficiently ligated. Immediately after chest tube placement, it presented extensive intrathoracic bleeding from the caudal intercostal artery. In view of the absolute necessity of a blood transfusion and given that compatible feline blood was not available, xenotransfusion of canine blood was administered to the cat and resulted in a positive outcome.

Successful xenotransfusion in a domestic ferret with spontaneous hemoperitoneum using feline packed red blood cells

OBJECTIVE

To describe the diagnosis, management, and outcome of a ferret with spontaneous hemoperitoneum with surgical intervention and xenotransfusion of type A feline packed red blood cells (pRBCs).

CASE SUMMARY

A domestic ferret diagnosed with a spontaneous hemoperitoneum secondary to a hepatic mass received isotonic crystalloids, hypertonic saline, and an allogenic blood transfusion perioperatively. Postoperatively, the ferret developed progressive anemia and tachycardia refractory to fluid therapy and, given a lack of additional allogenic blood sources, received a xenotransfusion of feline pRBCs. The ferret was hospitalized for 4 days postoperatively and developed a presumed delayed transfusion reaction characterized by transient hyperbilirubinemia. At a 6-month recheck, the ferret was doing well clinically.

NEW OR UNIQUE INFORMATION PROVIDED

This is the first reported case of successful xenotransfusion of feline pRBCs in a ferret. Although xenotransfusion of ferrets with feline blood products is not recommended as a routine procedure, it remains a viable option in critical situations in which ferret blood is unavailable.

Xenotransfusion of canine blood to cats: a review of 49 cases and their outcome

OBJECTIVES

To describe the use of a xenotransfusion protocol, the outcome of xenotransfusion in recipient cats and to assess owner memory of the xenotransfusion.

MATERIALS AND METHODS

Cats administered xenotransfusions in two hospitals between January 2016 and July 2018 were included. Adherence to xenotransfusion protocol, cause of anaemia, blood type, packed cell volume (PCV), transfusion volume, transfusion reactions, PCV 12 hours after transfusion and survival to discharge were recorded. Owners of surviving cats were questioned to assess if they remembered that a xenotransfusion had been performed.

RESULTS

Forty-nine cats underwent the xenotransfusion protocol. The most common causes of anaemia were surgical blood loss (n = 17), immune-mediated haemolytic anaemia (n = 14) and neoplasia (n = 14). Median PCV before transfusion was 10%. Six cats (12%) had febrile non-haemolytic transfusion reactions. Median PCV 12 hours after transfusion was 25%. Ten cats (20%) died or were euthanased within 24 hours of xenotransfusion. A delayed haemolytic transfusion reaction occurred in 25 of 39 (64%) cats manifesting as icterus in 15 cats after a median of 1.9 days and haemolytic serum in 19 cats after a median of 2 days. Of the 18 cats alive at 1 week after discharge, 15 (83%) were still alive at a median of 173 days after xenotransfusion. All owners contacted remembered that their cats had received a xenotransfusion.

CLINICAL SIGNIFICANCE

Xenotransfusion of canine packed red blood cells to cats is possible but haemolysis should be expected between 1 and 6 days after transfusion.

Detection of naturally occurring alloantibody by an in-clinic antiglobulin-enhanced and standard crossmatch gel column test in non-transfused domestic shorthair cats

Background

Blood typing for the A and B antigens is essential and crossmatching testing is generally recommended before transfusing blood to cats.

Objective

To evaluate 2 crossmatch (XM) tests.

Animals

Forty‐nine healthy domestic shorthair cats that had not received a blood transfusion.

Methods

Prospective study. Blood samples were typed for AB using immunochromatographic and flow cytometric techniques. A gel column (GC) and a feline antiglobulin‐enhanced gel column (AGC) XM tests were used for crossmatching.

Results

The population included 34 type A, 13 B, and 2 AB cats, with concordant results (r = 1, P < .005) by flow cytometry and immunochromatographic strip kit. The plasma from type A cats had either no or weak anti‐B alloantibodies. The plasma of 12 of 13 type B cats contained strong anti‐A alloantibodies. For crossmatching, plasma to RBC pairings were prepared using the GC (n = 446) and AGC (n = 630) tests. Both methods showed compatibilities in 329 and incompatibilities in 102 pairings including all A‐B mismatches. Additionally 15 pairings showed agglutination by the AGC but not GC method. Fourteen incompatibilities outside the expected A‐B mismatches were only revealed by AGC.

Conclusions and Clinical Importance

AB typing using immunochromatographic strip is as accurate as laboratory flow cytometry. The 2 XM methods had good agreement with additional incompatibilities being recognized by the AGC XM beyond A‐B incompatibilities. In clinic, feline AB typing and sensitive XM test kits are available and recommended before each transfusion, although the clinical implications of incompatible XM test results and clinical benefits of such crossmatching have not been documented.