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.


OBJECTIVE
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.
Department of Clinical Studies, School of Veterinary Medicine, University of Pennsylvania, Philadelphia, PA, USA.
Rebecca J
RJ
Kessler
Shelley
S
Rankin
Sheri
S
Young
Kathleen
K
O'Shea
Maria
M
Calabrese
Amy
A
Guldin
Nicole
N
Lipson
Donna A
DA
Oakley
Urs
U
Giger
D000818:Animals; D001769:Blood / Q000382:microbiology*; D001771:Blood Banks; D001782:Blood Donors; D001793:Blood Preservation; D002415:Cats / Q000097:blood*; D004285:Dogs / Q000097:blood*; D008297:Male; D016133:Polymerase Chain Reaction / Q000662:veterinary; D011551:Pseudomonas fluorescens / Q000235:genetics / Q000302:isolation & purification*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D013048:Specimen Handling / Q000662:veterinary*
D012336:RNA, Ribosomal, 16S