Stored Canine Whole Blood Units: What is the Real Risk of Bacterial Contamination?

Abstract

BackgroundBacterial contamination of whole blood (WB) units can result in transfusion‐transmitted infection, but the extent of the risk has not been established and may be underestimated in veterinary medicine.ObjectivesTo detect, quantify, and identify bacterial microorganisms in 49 canine WB units during their shelf life.AnimalsForty‐nine healthy adult dogs.MethodsForty‐nine WB units were included in the study. Immediately after collection, 8 sterile samples from the tube segment line of each unit were aseptically collected and tested for bacterial contamination on days 0, 1, 7, 14, 21, 28, 35, and 42 of storage. A qPCR assay was performed on days 0, 21, and 35 to identify and quantify any bacterial DNA.ResultsOn bacterial culture, 47/49 blood units were negative at all time points tested, 1 unit was positive for Enterococcus spp. on days 0 and 1, and 1 was positive for Escherichia coli on day 35. On qPCR assay, 26 of 49 blood units were positive on at least 1 time point and the bacterial loads of the sequences detected (Propionobacterium spp., Corynebacterium spp., Caulobacter spp., Pseudomonas spp., Enterococcus spp., Serratia spp., and Leucobacter spp.) were <80 genome equivalents (GE)/μL.Conclusions and Clinical ImportanceMost of the organisms detected were common bacteria, not usually implicated in septic transfusion reactions. The very low number of GE detected constitutes an acceptable risk of bacterial contamination, indicating that WB units have a good sanitary shelf life during commercial storage.

In vitro assessment of quality of citrate‐phosphate‐dextrose‐adenine‐1 preserved feline blood collected by a commercial closed system

“…Unfortunately, even if it is hard to state when the contamination happened, it is more likely that this event occurred during blood collection, considering that the isolated bacterial species, S. marcescens , is a member of the Enterobacteriaceae family and a Gram‐negative saprophytic bacillus, which has been often reported to be a bacterial contaminant of stored blood products . Moreover, even in the chance of contamination during collection, the standard culture methods could have resulted negative at T0 because of a low bacterial load . Furthermore, although a careful preparation of the skin before donation decreases the skin bacterial load, a sterile venipuncture cannot be guaranteed because the organisms which are present in the sebaceous glands and hair follicles are inaccessible .…”

“…[30][31][32] Moreover, even in the chance of contamination during collection, the standard culture methods could have resulted negative at T0 because of a low bacterial load. 33 Furthermore, although a careful preparation of the skin before donation decreases the skin bacterial load, a sterile venipuncture cannot be guaranteed because the organisms which are present in the sebaceous glands and hair follicles are inaccessible. 33 We therefore recommend thorough disinfection of the jugular area before collection and careful disinfection of the valve when sampling the bag.…”

Comparison of a closed system and an open system for blood collection in feline donors

“…In our study, the percentage of negative bacteriological units was high (94%), which is similar to the 96-100% observed in previous studies on feline and canine blood products. 12,[24][25][26] Staphylococcus species were the only isolated bacteria. We attribute this growth to a contamination during the laboratory procedures, that is, the manipulations for microbiological evaluation described in the materials and methods section, because the sample was negative by PCR at all time points.…”

“…The detection of bacterial DNA in blood with PCR has been described in only a few veterinary studies. 11,26 In one study, a PCR assay was performed on days 0, 21 and 35 on stored canine whole blood units and 53% of blood units were positive at one time point. 26 Interestingly, in the current study, four units were positive at T0 and negative thereafter.…”

Incidence of Bacteremia Consequent to Different Endoscopic Procedures in Dogs: A Preliminary Study

“…In these dogs, the isolated microorganisms were found to be bacteria belonging to normal canine microflora or contaminants, such as Serratia marcescens [23]. Even using aseptic manual manipulation, a certain percentage of blood culture contamination is also described in human medicine [24][25][26].…”