Hazards of bacterial contamination of blood products

Area of Science:

• Transfusion Medicine
• Infectious Diseases
• Microbiology

Background:

• Post-transfusion bacterial sepsis, while infrequent, carries a high mortality rate due to septic shock, often linked to endotoxin release from gram-negative bacteria.
• Lesser transfusion reactions, frequently caused by gram-positive bacteria like staphylococci, are often under-reported.
• Contamination sources include endogenous donor bacteremia (e.g., Yersinia enterocolitica) and exogenous factors from collection defects.

Purpose of the Study:

• To highlight the risks associated with bacterial contamination in blood products.
• To differentiate bacterial causes based on storage conditions (room temperature vs. refrigerated).
• To emphasize the importance of stringent protocols in preventing transfusion-acquired infections.

Main Methods:

• Review of literature on bacterial contamination in blood transfusions.
• Identification of common bacterial species associated with transfusion reactions based on storage temperature.
• Analysis of endogenous and exogenous sources of contamination.

Main Results:

• Gram-negative psychrophilic species (e.g., Yersinia enterocolitica, Pseudomonas fluorescens) are cultured from refrigerated blood implicated in reactions.
• Gram-positive bacteria (e.g., staphylococci) are cultured from room-temperature stored platelets.
• Transfusion-acquired syphilis is now rare, but protozoal infections remain a concern in developing countries.

Conclusions:

• Preventing transfusion reactions requires meticulous attention to collection, storage, reissuing, and infusion processes.
• Prompt reporting, testing, and treatment of suspected reactions are vital.
• Ensuring blood safety necessitates robust screening and adherence to best practices in transfusion medicine.