Explore the vast range of titles available.

Abstract Background Reported incidence of blood transfusion reactions (TR) varies greatly. Objective To prospectively evaluate the incidence of acute TRs in dogs receiving allogenic blood products, using consensus definitions, and to assess factors associated with TRs. Animals Dogs (n = 858) administered allogenic blood products (n = 1542) between March and November 2022. Methods Prospective, multicenter surveillance study occurring in referral hospitals in the United States, United Kingdom, and Australia recording TRs in dogs administered blood products as defined by the consensus guidelines published by The Association of Veterinary Hematology and Transfusion Medicine in 2021. Results The incidence of acute TR was 8.9% (95% CI 7.0-11.1) for packed red blood cells (pRBCs) and 4.5% (95% CI 2.9-6.6) for plasma products. The most frequently reported TRs were febrile nonhemolytic TRs (FNHTR; 4%, 95% CI 2.8-5.5) when administering pRBCs and allergic TRs (3.2%, 95% CI 1.80-5.10) when administering plasma products. A higher dose of pRBC (adjusted odds ratio [aOR] 1.04 [95% CI 1.00-1.08]) was associated with a higher odds of TR. Administration of pRBCs stored for longer than 28 days was associated with higher odds of FNHTR (aOR 4.10 [95% CI 1.58-10.65]) and acute hemolytic TR (AHTR; OR 15.2 [95% CI 3.35-68.70]) when compared with pRBCs stored for 14 days or fewer. Leukoreduction of pRBC was not associated with lower odds of developing a TR (OR 1.47 [95% CI 0.89-2.42]). Conclusions and Clinical Importance Clinicians should be mindful of the age and dose of pRBC prescribed to dogs.

Abstract Background Transfusions in camelid species are performed without evidence-based guidelines. Safe and recommended practices for administering blood products with maximal efficacy and minimal risk of reactions are needed. Hypothesis/Objectives To describe the indications for, methods of, and outcomes associated with transfusions in camelids and to identify risk factors for transfusion reactions (TRs) and death. Animals Two hundred four transfusions performed in 169 camelids at 2 referral hospitals. Methods A dual-center retrospective review of medical records from 2010 to 2024. Signalment, indication for transfusion, transfusion history, administration of premedication, presence of TRs, and survival to discharge were reviewed. Dose and rate of product administration were calculated. Data were described and analyzed with a generalized linear model. Results In less than 1-month-old crias, the most common indication for plasma transfusion was management of failure of transfer of passive immunity. The overall TR rate was 12%, and presence of TRs resulted in a lower probability of survival to discharge (54.6%; 95%CI, 34.0%-73.6% vs 76.5%; 95%CI, 69.5%-82.3%, respectively; P = .033). There was no difference in probability of a TR with respect to administration of premedication, rate of transfusion administration, or previous transfusions (P ≥ .06). Changes to vital signs were the most common findings suggesting a TR. Conclusions and Clinical Importance Blood products can fulfill many therapeutic needs in the treatment of camelid species with a reasonable expectation of safety. A history of prior transfusions does not appear to significantly affect the future risk of a TR.

Abstract Background The reported incidence of blood product transfusion reaction (TR) in cats varies greatly. Objective Evaluate the incidence and practices surrounding acute TRs in cats receiving feline blood products, using Transfusion Reaction Small Animal Consensus Statement (TRACS) definitions. Animals Cats (n = 444) that received feline blood products (n = 608) between March 2022 and January 2024. Methods Prospective, multicenter observational study at referral hospitals (n = 14) in the United States, United Kingdom, and Australia documenting the incidence of acute TRs in cats receiving allogenic blood transfusions. Results Acute TR incidence was 7.8% (95% confidence interval [CI], 5.6–10.6) for red blood cell (RBC)-containing products and 1.1% (95% CI, 0.0–5.9) for plasma products. Febrile nonhemolytic transfusion reactions (FNHTRs) were the most common in RBC-containing products (incidence, 5.7%; 95% CI, 3.8–8.1). Age of RBC unit (adjusted odds ratio [aOR], 1.04 per day; 95% CI, 1.00–1.07) and administering a RBC unit with an infusion pump rather than a syringe driver (aOR, 4.7; 95% CI, 1.43–15.54) were associated with an increased odds of FNHTR. Of transfusions discontinued (n = 28) because of a potential TR, 46.4% did not fulfill TRACS criteria for any TR. Death occurred within 24 h of a transfusion event in 18.3% but was not associated with the development of a TR (odds ratio [OR], 0.76; 95% CI, 0.29–1.99). Conclusions and Clinical Importance Transfusion reaction incidence in cats, as defined using TRACS guidelines, is reported. Febrile nonhemolytic TRs were the most common and were associated with increasing RBC unit age and administering RBC via an infusion pump.

Abstract Background Novel feline RBC antigens might contribute to decreased efficacy of RBC transfusion and increased incidence of acute transfusion reactions (ATR). Objectives To examine the effect of major cross-match in transfusion-naïve anemic cats on the incidence of acute immunologic transfusion reaction and transfusion efficacy for up to 24 hours after transfusion. Animals Forty-eight client owned transfusion-naïve anemic cats. Methods Prospective, randomized, controlled study. All transfusion-naïve cats receiving packed red blood cells (pRBC) transfusions from January 2016 to August 2017 were eligible for inclusion. Cats in the study group received cross-match and blood type compatible pRBCs and cats in the control group received noncross-matched blood type compatible pRBCs. Incidence of ATR and change in PCV after transfusion was recorded. Results No significant difference in incidence of transfusion reactions between cross-matched and noncross-matched groups (CM+ 4/24; 17%, CM– 7/24; 29%, P = .16). No significant difference between groups in mean change in PCV after transfusion scaled to dose of pRBCs administered at any time point after transfusion (immediate: CM+ 0.62 ± 0.59, CM– 0.75 ± 0.48, P = .41; 1 hour: CM+ 0.60 ± 0.66, CM– 0.74 ± 0.53, P = .43; 12 hours: CM+ 0.70 ± 0.55, CM– 0.66 ± 0.60, P = .81; 24 hours: CM+ 0.64 ± 0.71, CM– 0.55 ± 0.48, P = .70). Conclusions and Clinical Importance Our results do not support use of the major cross-match test to increase efficacy of, and to decrease adverse events associated with, RBC transfusion in AB blood typed transfusion-naïve cats.

Abstract We report on the identification of bovine bosavirus associated with a post-transfusion hepatopathy in a 4-month-old Holstein bull calf that was referred for enteritis and fever of unknown origin. Next-generation sequencing (NGS) of post-transfusion blood and liver tissue from the calf, alongside NGS of plasma from the donor, identified a bovine bosavirus. This virus has been previously identified in bovine calf serum, calves with mucosal disease, and the blood of bison but was of uncertain clinical importance. These findings have biosecurity implications for clinicians using bovine whole blood or plasma therapeutically and suggest the need for pre- or postharvest donor screening or biologic processing to prevent infection of recipients. The calf made a full clinical recovery.

Abstract Background In humans, washing stored blood products before transfusion reduces storage lesions and incidence of transfusion reactions, but the effectiveness of washing canine blood is unknown. Objectives The objective was to determine if manually washing units of stored blood would reduce storage lesions without adversely affecting erythrocytes. We hypothesized that washing stored units would reduce concentrations of storage lesions and cause minimal erythrocyte damage. Animals Eight healthy research dogs. Methods Repeated measure cohort study. Units of whole blood were stored for 28 days and washed 3 times with 0.9% NaCl. Blood samples were collected before and after storage, after each wash, and after being held at a simulated transfusion temperature. Variables measured included CBC variables, blood gas analysis, erythrocyte morphology, mean corpuscular fragility (MCF), and eicosanoid concentrations. A Friedman's test was used to evaluate changes in variables (P < .05 was considered significant). Results After the first wash, compared to values after storage, there was a significant decrease in potassium (4.3 mmol/L [4.0-4.7] to 1.2 mmol/L [1-1.6]; P < .0001, median [range]), lactate (1.45 mmol/L [1.07-1.79] to 0.69 mmol/L [0.39-0.93]; P = .002), and partial pressure carbon dioxide (102 mm Hg [80.2-119.2] to 33.7 mm Hg [24.5-44.5]; P < .0001), and increase in MCV (69.3 fL [65.7-72.3] to 74 fL [69.6-79.5]; P = .0003), and MCF (0.444 fL [0.279-0.527] to 0.491 fL [0.43-0.616]; P = .0006). Conclusions and Clinical Importance A single wash of stored whole blood significantly reduces most extracellular storage lesions, and additional washing might cause hemolysis.

Abstract Background Calculation of desired whole blood transfusion volume relies on an estimate of an animal's circulating blood volume, generally accepted to be 0.08 L/kg or 8% of the animal's body weight in kilograms. Objective To use packed cell volume before and after whole blood transfusion to evaluate the accuracy of a commonly used equation to predict packed cell volume after transfusion in small ruminants and South American camelids; to determine the nature and frequency of adverse transfusion reactions in small ruminants and camelids after whole blood transfusion. Animals Fifty-eight small ruminants and 22 alpacas that received whole blood transfusions for anemia. Methods Retrospective case series; medical record review for small ruminants and camelids that received whole blood transfusions during hospitalization. Results Mean volume of distribution of blood as a fraction of body weight in sheep (0.075 L/kg, 7.5% BW) and goats (0.076 L/kg, 7.6% BW) differed significantly (P < 0.01) from alpacas (0.103 L/kg, 10.3% BW). Mild transfusion reactions were noted in 16% of transfusions. Conclusions and Clinical Relevance The generally accepted value of 8% for circulating blood volume (volume of distribution of blood) is adequate for calculation of transfusion volumes; however, use of the species-specific circulating blood volume can improve calculation of transfusion volume to predict and achieve desired packed cell volume. The incidence of transfusion reactions in small ruminants and camelids is low.

Background The demand for blood transfusions in veterinary medicine is increasing in South Korea, particularly for canine patients. While dog erythrocyte antigen (DEA) 1 is a known cause of acute hemolytic reactions, previous studies have underscored the involvement of DEA 4 and Dal. However, research on these crucial antigens remains limited in South Korea compared to North America and Europe, resulting in a knowledge gap concerning transfusion risks. We aimed to investigate the prevalence of the Dal and DEA 1 and 4 blood types among canine blood donors and recipients in Seoul. Residual blood samples were collected from 105 donor and recipient dogs admitted to the Konkuk Veterinary Medical Teaching Hospital between April and September 2023. The DEA type 1 blood type was identified using immunochromatographic strip technology, while Dal and DEA 4 blood types were determined through agglutination reactions on specialized test cards. Results Among the 105 dogs, 74 (70.48%) tested positive for DEA 1, 97 (92.38%) were DEA 4-positive, and 81 (77.14%) were Dal-positive. Some breeds not previously associated with Dal-negative outcomes, including nine Labrador Retrievers, five Golden Retrievers, a Shepherd, a Siberian Husky, an American Bully, a Miniature Poodle, and a Pungsan dog, tested negative for Dal on agglutination tests. Similarly, three Labrador Retrievers, three Golden Retrievers, one Samoyed, and one Doberman Pinscher tested negative for DEA 4. Larger breeds generally exhibited a lower prevalence for all tested blood types. The prevalence of DEA 1 observed in this study (70.48%) is consistent with prior studies; however, Dal and DEA 4 exhibited lower prevalence rates than those reported in Europe and North Americas, with Dal at 77.14% (compared to 89.3–100%) and DEA 4 at 92.38% (compared to 98.8–100%). Notably, breeds such as Labrador Retrievers, the most represented breed in our sample, exhibited low prevalence, suggesting that they may be an optimal donor in Seoul. Conclusion The distributions of DEA 1, DEA 4, and Dal blood types may reveal distinct prevalence patterns in Seoul, South Korea, possibly due to geographical differences, as existing data primarily reflect findings from European and North American.

Abstract Background Recognition of the feline red blood cell (RBC) antigen Mik and the presence of naturally occurring anti-Mik antibodies resulting in acute hemolytic transfusion reactions prompted the recommendation to perform a crossmatch before a cat's first RBC transfusion, but this guideline has not yet become a standard practice. Objective To determine the prevalence of naturally occurring non-AB alloantibodies detectable by tube crossmatch, and to compare transfusion outcomes in cats with and without a crossmatch performed. Animals Three hundred cats that received an RBC transfusion, with or without a major crossmatch performed. Methods Retrospective study. Results Major crossmatch incompatibilities were documented in 23 of 154 transfusion-naive cats (14.9%) and in 15 of 55 previously transfused cats (27%; P = 0.042). Type-specific packed RBCs (pRBCs) were administered to 167 and 82 cats with and without a crossmatch, respectively. Median volume of pRBCs administered during the first transfusion was 5.3 mL/kg (range, 2.4-18 mL/kg). Median change in PCV scaled to dose of pRBCs was +0.8%/mL/kg; administration of crossmatch-compatible pRBCs was not associated with a greater increase in PCV. Febrile transfusion reactions occurred more often in cats that received non-crossmatched (10.1%) compared to crossmatched (2.5%) pRBCs (P = 0.022). Seventy-six percent of cats that received pRBC transfusions survived to hospital discharge. A crossmatch was not associated with improved survival to discharge or at 30 or 60 days posttransfusion. Conclusions and Clinical Importance The prevalence of naturally occurring non-AB incompatibilities is sufficiently high to justify the recommendation to perform a crossmatch before all (including the first) RBC transfusions in cats.

Background Cytauxzoonosis is an emerging tick-borne disease of domestic and wild felids. Cytauxzoon felis induces severe and often fatal disease in domestic cats. In Europe, clinical and subclinical infections caused by Cytauxzoon sp. are described. We report the first cases of Cytauxzoon sp. infection in domestic cats in Switzerland. Methods Clinical and laboratory data and results of PCR analyses were collected from Cytauxzoon sp. PCR-positive cats and the cats followed for up to 851 days. Results The cases were three two-month old kittens from the same litter (Cases 1–3) and two adult domestic shorthair cats (Cases 4 and 5). The cats originated from the north-west and west of Switzerland. Cases 1–3 presented with moderate to severe regenerative anaemia and intraerythrocytic inclusions. Cytauxzoon sp . was confirmed by PCR and sequencing . The kittens made a clinical and haematological recovery after blood transfusion and/or treatment with azithromycin and atovaquone, but erythroparasitaemia persisted. Case 4 presented with severe non-regenerative anaemia. Case 5 was healthy and used as a blood donor for Case 4. Following blood transfusion, Case 4 showed intraerythrocytic inclusions, and Cytauxzoon sp . was confirmed in both Cases 4 and 5 using PCR and sequencing. Case 4 achieved clinical and haematological remission after treatment with azithromycin, atovaquone and immunosuppressive drugs. Eight months later, Case 4 was presented again with anaemia but tested Cytauxzoon sp. PCR-negative. Sequencing of 1637 bp of the 18S rRNA gene of Cytauxzoon sp . revealed 100% nucleotide sequence identity among isolates of Cases 1–3 and between isolates of Cases 4 and 5, and 99% sequence identity between isolates of all cases. Phylogenetic analysis revealed the closest relationship of the Swiss isolates to Cytauxzoon sp . isolates from domestic cats and wild felids from France, Spain and Romania and to Cytauxzoon manul from a Pallas’s cat. Conclusions This is the first report of Cytauxzoon sp . infection in domestic cats in Switzerland. It is also the first report of infection in very young kittens and transmission of Cytauxzoon sp . to an adult cat by transfusion of blood from an asymptomatic cat. The cats recovered but some developed chronic asymptomatic erythroparasitaemia for up to 28 months. Domestic cats may act as reservoirs for Cytauxzoon sp. in Europe and blood donor cats should be screened for this agent by PCR.