Veterinary Transfusion Medicine Research Articles

Retrospective Longitudinal Survey on Canine Vector-Borne Pathogens: Trends and Challenges of 10 Years of Activities of a Veterinary Blood Bank.

Canine vector-borne pathogens (CVBPs) represent a challenge for veterinary transfusion medicine, since some can be transmitted by blood transfusion and are of zoonotic concern. Epidemiological data on CVBPs, obtained during 10 years of pre-donor screening (2012–2021) by a veterinary blood bank in central Italy, were used to conduct a retrospective epidemiological longitudinal survey. The results were obtained using the Immunofluorescent Antibody Test (IFAT) conducted on sera in order to assess IgG antibodies against Leishmania infantum, Ehrlichia canis, Anaplasma phagocythophilum, Babesia canis, and Rickettsia conorii; the modified Knott’s test and an ELISA kit were used to detect Dirofilaria immitis and Dirofilaria repens. In total, 324 out of the 1260 canine blood donors (25.71%) tested seropositive for at least one pathogen. The highest overall positive rate was detected for L. infantum (12.22%), followed by E. canis (2.30%), A. phagocytophilum (1.19%), D. repens (0.95%), D. immitis (0.32%), and B. canis (0.16%). From 2012 to 2014, a prevalence of 20.12% was recorded for R. conorii. Mixed infections were recorded in 21 dogs. For all the CVBPs investigated, significant differences (p < 0.05) were not observed over the period studied. The results evidenced a non-negligible prevalence of CVBPs in canine donors, which were selected based on strict criteria concerning regular endo- and ectoparasite controls. The results confirmed that the blood bank could be a reliable local epidemiological observatory. The need for implemented screening is discussed.

Association of Veterinary Hematology and Transfusion Medicine (AVHTM) transfusion reaction small animal consensus statement (TRACS). Part 3: Diagnosis and treatment

To systematically review available evidence to develop guidelines for diagnosis and treatment of transfusion-associated reactions in dogs and cats. Standardized and systemic evaluation of the literature (identified through Medline via PubMed and Google Scholar searches) was carried out for identified transfusion reaction types in dogs and cats. The available evidence was evaluated using PICO (Population, Intervention, Comparison, Outcome) questions generated for each reaction type. The evidence was categorized by level of evidence (LOE) and quality (Good, Fair, or Poor). Guidelines, diagnostic, and treatment algorithms were generated based on the evaluation of the evidence. Consensus on the final guidelines was achieved through Delphi-style surveys. Draft recommendations were disseminated through veterinary specialty listservs for review and comments, which were evaluated and integrated prior to final publication. Medline via PubMed and Google Scholar databases were searched. There were 14 Population Intervention Comparison Outcome questions identified and corresponding worksheets were developed focusing on the diagnosis and treatment of transfusion-associated reactions in dogs and cats. Fourteen guidelines and four algorithms were developed with a high degree of consensus. This systematic evidence evaluation process yielded recommended diagnostic and treatment algorithms for use in practice. However, significant knowledge gaps were identified, demonstrating the need for additional research in veterinary transfusion medicine.

Current issues in veterinary transfusion medicine

Human and veterinary transfusion medicine is an area where there has been ongoing research and new developments. The way in which blood and transfusion products have been used has been questioned resulting in changes in their use and storage. In transfusion medicine, not only the research methods, but sometimes the application of the product itself, has raised ethical and moral questions, which has in part led to major differences between UK and US transfusion practices. Within the UK there is a rapidly growing demand for banked blood products and an increasing use in practice of both banked products and emergency whole blood donations. Registered veterinary nurses (RVNs) are now able to undertake further qualifications in emergency and critical care which includes the use of blood products. It is of vital importance for the RVN to keep up to date with current thinking on transfusion medicine and to ensure that transfusion guidelines and protocols within their work-place are up to date and evidence based.

Freezing and storage of leukodepleted erythrocyte suspensions

Studies on the frozen storage of human blood products have benefited veterinary transfusion medicine in recent years, but the long-term cryopreservation of canine red blood cells (RBCs) has not yet been thoroughly investigated. Further, no studies are available with respect to the frozen storage of leukocyte-depleted canine red blood cells (LD-RBCs). The objective of the current study was to investigate time-dependent effects of long-term frozen storage on leukocyte-depleted canine RBCs. Twelve healthy adult dogs meeting the criteria for blood transfusion were used in the study. Whole blood samples (450 ± 45 ml) collected from each dog were centrifuged for 5 min at 22 °C and 4200 × g in a cryogenic microcentrifuge and concentrated RBC (pRBC) suspensions were obtained. Leukocyte depletion was achieved by filtration (2.6 log&lt;sub&gt;10&lt;/sub&gt;). Then, the filtrated samples were prewashed three times in 0.9% NaCl solution and were allocated into three subgroups to be evaluated at three different time points (Day 0, Month 4 and Month 6). The samples for cryopreservation were subjected to glycerolisation and then stored at –80 °C for 4- and 6-month periods. At the end of this period pRBC units were thawed by manual agitation in a water bath maintained at 36–38 °C, centrifuged and then washed in a consecutive series of 12%, 1.6% and 0.9% of NaCl + 0.2 dextrose solutions. 2,3-Diphosphoglycerate (2,3-DPG), adenosine triphosphate (ATP), supernatant haemoglobin (SupHb), sodium (Na&lt;sup&gt;+&lt;/sup&gt;) and potassium (K&lt;sup&gt;+&lt;/sup&gt;) levels, residual glycerol concentrations and haemograms of thawed and deglycerolised pRBC samples were evaluated together with those of Day 0. Sterility tests were performed on all samples for bacterial contamination. No statistically significant differences were noted except for Hct and SupHb levels. No bacterial contamination was noted in any of the samples on the basis of sterility tests. It was found that the described glycerolisation procedure could be a method of choice in the cryopreservation of leukocyte-depleted pRBCs (LD-pRBCs) since no negative effect was observed on the quality of the products and long-term frozen storage did not cause RBC destruction.

Detection of bacterial contamination and DNA quantification in stored blood units in 2 veterinary hospital blood banks.

Blood transfusions in veterinary medicine have become increasingly more common and are now an integral part of lifesaving and advanced treatment in small and large animals. Important risks associated with transfusion of blood products include the transmission of various infectious diseases. Several guidelines suggest what infectious agents to screen for in canine and feline transfusion medicine. However, while the risk of bacterial contamination of blood products during storage and administration has not been documented in veterinary medicine, it has emerged as a cause of morbidity and mortality in human transfusion medicine. Clinical experience shows that the majority of blood component bacterial contaminations are caused by only a few species. Unlike other types of bacteria, psychrotolerant species like Pseudomonas spp. and Serratia spp. can proliferate during the storage of blood units at 4°C from a very low titer at the time of blood collection to a clinically significant level (> 10(5) CFU/mL) causing clinical sepsis resulting from red blood cell concentrate transfusions in human medicine. The purpose of this report was to describe the detection and quantification procedures applied in 4 cases of bacterial contamination of canine and feline blood units, which suggest the need for further investigations to optimize patients' safety in veterinary transfusion medicine.

Frequencies of DEA blood types in a purebred canine blood donor population in Porto Alegre, RS, Brazil

The study of canine immunohematology is very important for veterinary transfusion medicine. The objective of this study was to determine the DEA blood type frequencies in a purebred canine blood donor population from Porto Alegre, RS, Brazil. One hundred clinically healthy purebred dogs were chosen, 20 dogs from each breed (Great Dane, Rottweiler, Golden Retriever, German Shepherd and Argentine Dogo). Blood samples were taken in ACD-A tubes and the MSU hemagglutination tube test (MI, USA) was used to determine the blood types. The studied population presented general frequencies of 61% for DEA 1.1, 22% for DEA 1.2, 7% for DEA 3, 100% for DEA 4, 9% for DEA 5 and 16% for DEA 7. A significant association was found between breeds and certain combinations of blood types in this population. The results are in agreement with the literature since most part of the canine population studied was positive for DEA 1.1, the most antigenic blood type in dogs. Differences were found among the studied breeds and those should be considered when selecting a blood donor. The knowledge of blood types frequencies and their combinations in different canine populations, including different breeds, is important because it shows the particularities of each group, helps to keep a data bank of local frequencies and minimizes the risks of transfusion reactions.

Increasing patient safety in veterinary transfusion medicine: an overview of pretransfusion testing

To review the principles and available technology for pretransfusion testing in veterinary medicine and discuss the indications and importance of test performance before RBC transfusion. Current human and veterinary medical literature: original research articles and scientific reviews. Indications for RBC transfusion in veterinary medicine include severe anemia or tissue hypoxia resulting from blood loss, decreased erythrocyte production, and hemolyzing conditions such as immune-mediated anemia and neonatal isoerythrolysis. Proper blood sample collection, handling, and identification are imperative for high-quality pretransfusion testing. Point-of-care blood typing methods including both typing cards and rapid gel agglutination are readily available for some species. Following blood typing, crossmatching is performed on one or more donor units of appropriate blood type. As an alternative to technically demanding tube crossmatching methods, a point-of-care gel agglutination method has recently become available for use in dogs and cats. Crossmatching reduces the risk of hemolytic transfusion reactions but does not completely eliminate the risk of other types of transfusion reactions in veterinary patients, and for this reason, all transfusion reactions should be appropriately documented and investigated. The administration of blood products is a resource-intensive function of veterinary medicine and optimizing patient safety in transfusion medicine is multifaceted. Adverse reactions can be life threatening. Appropriate donor screening and collection combined with pretransfusion testing decreases the occurrence of incompatible transfusion reactions.

Importance of blood groups and blood group antibodies in companion animals

Dogs, cats, birds, and ferrets are popular companion animals. Because these pets are considered by many to be family members, they are provided high-quality veterinary medical care, including blood transfusions. This article reviews the current status of blood groups in dogs, cats, birds, and ferrets and discusses the impact of blood groups on veterinary transfusion medicine. One blood group with 3 types has been described in the cat, whereas multiple blood groups have been described in the dog. Only rudimentary knowledge exists regarding pet bird blood groups, and, to date, the ferret appears to be unique because no blood groups have been described. Antibodies against blood group antigens also play a role in animal blood transfusions. Cats have naturally occurring alloantibodies; however, dogs do not appear to have clinically significant naturally occurring alloantibodies. Understanding the issues related to blood groups and blood group antibodies in companion animals will also benefit those using these species as research models for human diseases.

Canine Blood Groups and their Importance in Veterinary Transfusion Medicine

Over 13 canine blood groups have been described. Eight DEA types are recognized as international standards. Typing sera produced by canine alloimmunization exists for six DEA types: 1.1, 1.2, 3, 4, 5, and 7. Naturally occurring antibody is found against DEA 3, 5, and 7. DEA 1.1 and 1.2 antibody-antigen interactions result in acute hemolytic transfusion reactions. DEA 3, 5, and 7 antibody-antigen interaction in vivo results in permanent red blood cell sequestration and loss in 3 to 5 days. DEA 4 antibody-antigen interactions produce no effect on red blood cell survival in vivo. A dog possessing DEA 4 and no other antigen is considered a "universal" donors. Veterinary transfusion medicine has advanced beyond uncrossmatched, untyped red blood cell transfusion. Whenever possible, transfusion should be between typed and crossmatched individuals. "Universal" donors and crossmatch should be utilized when typing of the recipient is not feasible. Canine blood typing is routinely performed in service laboratories across North America. In-clinic assays are not available for all canine blood group antigens. Recent production of monoclonal antibodies will lead to biochemical definition of the canine blood groups DEA 1.1 and 3. Additional efforts to define the erythrocytes on a molecular level are underway. Advances efforts in this areal will allow for more rapid and uniform testing of the canine red blood cell. Future exploration of DEA type and disease association is needed. A known association exists between DEA 1.1 and neonatal isoerythrolysis. Further screening of the dog population for DEA type may yield markers for autoimmune and neoplastic disease.

Selection of Anticoagulant-Preservatives for Canine and Feline Blood Storage

Blood or blood component transfusions have become a well recognized, lifesaving form of therapy in veterinary medicine. Blood used for small animal transfusions may be collected and prepared with a variety of anticoagulants, anticoagulant-preservatives, or additive solutions. Selection of the most appropriate of these collection or storage solutions requires a knowledge of their formulations and of the shelf-lives previously established for storage of canine or feline red blood cells. Other factors that should be considered in the selection process are based on the specific transfusion needs of a clinic and its patients, including whether the blood will be used fresh or stored, the length of storage time desired, and whether components will be prepared. New products and techniques for blood storage continue to be developed, offering exciting new possibilities for the future practice of veterinary transfusion medicine.