Dog erythrocyte antigens 1.1, 1.2, 3, 4, 7, and Dal blood typing and cross-matching by gel column technique.

BACKGROUND: Testing for canine blood types other than dog erythrocyte antigen 1.1 (DEA 1.1) is controversial and complicated by reagent availability and methodology. OBJECTIVES: The objectives of this study were to use available gel column technology to develop an extended blood-typing method using polyclonal reagents for DEA 1.1, 1.2, 3, 4, 7, and Dal and to assess the use of gel columns for cross-matching. METHODS: Dogs (43-75) were typed for DEA 1.1, 1.2, 3, 4, 7, and Dal. METHODS included tube agglutination (Tube) using polyclonal reagents, a commercially available DEA 1.1 gel column test kit (Standard-Gel) using monoclonal reagent, and multiple gel columns (Extended-Gel) using polyclonal reagents. Blood from 10 recipient and 15 donor dogs was typed as described above and cross-matched using the gel column technique. RESULTS: Of 43 dogs typed for DEA 1.1, 23, 25, and 20 dogs were positive using Standard-Gel, Extended-Gel, and Tube, respectively. Typing for DEA 1.2 was not achievable with Extended-Gel. For 75 dogs typed for DEA 3, 4, and 7, concordance of Extended-Gel with Tube was 94.7%, 100%, and 84%, respectively. Dal, determined only by Extended-Gel, was positive for all dogs. Post-transfusion major cross-matches were incompatible in 10 of 14 pairings, but none were associated with demonstrable blood type incompatibilities. CONCLUSIONS: Gel column methodology can be adapted for use with polyclonal reagents for detecting DEA 1.1, 3, 4, 7, and Dal. Agglutination reactions are similar between Extended-Gel and Tube, but are more easily interpreted with Extended-Gel. When using gel columns for cross-matching, incompatible blood cross-matches can be detected following sensitization by transfusion, although in this study incompatibilities associated with any tested DEA or Dal antigens were not found.

Pseudomonas fluorescens contamination of a feline packed red blood cell unit and studies of canine units.

BACKGROUND: While screening programs have reduced the risk of infectious disease transmission by donors in human and veterinary blood banking, bacterial contamination of blood products has emerged as a major complication in human medicine. OBJECTIVES: To describe a Pseudomonas fluorescens (Pf)-contaminated feline packed RBC (pRBC) unit and experimentally investigate Pf-contaminated canine pRBCs. METHODS: Canine pRBCs were inoculated with Pf-rich pRBCs from the sentinel feline unit and stored at 4 degrees C or 20 degrees C for 72 hours. Aliquots from the pRBCs were serially evaluated by microscopy, culture, and a eubacterial 16S rRNA real-time PCR assay. RESULTS: One Pf-contaminated feline unit turned black after 22 days of storage and was removed from the blood bank; a source was not found, and no other contaminated units were identified. Canine pRBCs spiked with 5 or 25 microL of the sentinel unit became culture- and/or 16S PCR-positive at > or =8 hours at 20 degrees C and 48 hours at 4 degrees C and developed a color change at > or =24 hours. Sensitivity studies indicated that without incubation, inoculation of > or =100 microL Pf-rich pRBCs was necessary for a positive 16S PCR test result. CONCLUSIONS: P. fluorescens grows in stored pRBCs slowly at 4 degrees C and rapidly at 20 degrees C. Screening of blood products for color change, estimating bacterial concentration with microscopy, and 16S PCR testing are simple and fast ways to detect bacteria in stored blood. Aseptic collection, temperature-controlled storage, and regular visual monitoring of stored units is recommended. Discolored units should not be transfused, but examined for bacterial contamination or other blood product quality problems.