Proliferation of psychrotrophic bacteria in cold-stored platelet concentrates.

Background And Objectives: Platelet concentrates (PC) are stored at 20-24°C to maintain platelet functionality, which may promote growth of contaminant bacteria. Alternatively, cold storage of PC limits bacterial growth; however, data related to proliferation of psychotrophic species in cold-stored PC (CSP) are scarce, which is addressed in this study.

Materials And Methods: Eight laboratories participated in this study with a pool/split approach.

Comparison of Bacterial Risk in Cryo AHF and Pathogen Reduced Cryoprecipitated Fibrinogen Complex.

Until November 2020, cryoprecipitated antihaemophilic factor (cryo AHF) was the only United States Food and Drug Administration (FDA)-approved fibrinogen source to treat acquired bleeding. The post-thaw shelf life of cryo AHF is limited, in part, by infectious disease risk. Concerns over product wastage demand that cryo AHF is thawed as needed, with thawing times delaying the treatment of coagulopathic patients.

Fatal sepsis associated with a storage container leak permitting platelet contamination with environmental bacteria after pathogen reduction.

Background: Pathogen reduction technology and enhanced bacterial culture screening promise to significantly reduce the risk of transfusion-associated septic reactions due to contaminated platelets. Recent reports suggest that these interventions lack efficacy for post-collection and processing contamination with environmental organisms if the storage bag integrity is compromised.

Case Report: We report a fatal septic transfusion reaction in a 63-year-old patient with chronic kidney and liver disease who received a pathogen reduced platelet transfusion in anticipation of surgery.

Establishment of transfusion-relevant bacteria reference strains for red blood cells.

Background And Objectives: Red blood cell concentrates (RBCC) are susceptible to bacterial contamination despite cold storage. A reliable evaluation of strategies to minimize the risk of RBCC-associated bacterial transmission requires the use of suitable reference bacteria. Already existing Transfusion-Relevant Bacteria Reference Strains (TRBRS) for platelet concentrates fail to grow in RBCC.

Sepsis from an apheresis platelet contaminated with Acinetobacter calcoaceticus/baumannii complex bacteria and Staphylococcus saprophyticus after pathogen reduction.

Background: Strategies to reduce platelet (PLT) bacterial contamination include donor screening, skin disinfection, sample diversion, bacterial culture, pathogen reduction (PR), and day-of-transfusion tests. We report bacterial sepsis following a pathogen-reduced PLT transfusion.

Case Report: An adult male with relapsed acute lymphoblastic leukemia was successfully treated for central catheter-associated Staphylococcus aureus bacteremia.

Phagocytosis and killing of Staphylococcus aureus by human neutrophils.

Neutrophils are essential for host defense against Staphylococcus aureus infections. Although significant progress has been made, our understanding of neutrophil interactions with S. aureus remains incomplete.

A NET Outcome.

Neutrophils constitute a critical part of innate immunity and are well known for their ability to phagocytose and kill invading microorganisms. The microbicidal processes employed by neutrophils are highly effective at killing most ingested bacteria and fungi. However, an alternative non-phagocytic antimicrobial mechanism of neutrophils has been proposed whereby microorganisms are eliminated by neutrophil extracellular traps (NETs).

Characterization of fatty acid modifying enzyme activity in staphylococcal mastitis isolates and other bacteria.

Background: Fatty acid modifying enzyme (FAME) has been shown to modify free fatty acids to alleviate their bactericidal effect by esterifying fatty acids to cholesterol or alcohols. Although it has been shown in previous studies that FAME is required for Staphylococcus aureus survival in skin abscesses, FAME is poorly studied compared to other virulence factors. FAME activity had also been detected in coagulase-negative staphylococci (CNS).