Transfusion with refrigerated blood resulted in endotoxic shock; which organism likely involved?

• A. Campylobacter fetus
• B. Neisseria meningitidis
• C. Pseudomonas aeruginosa
• D. Yersinia enterocolitica

Answer: (D)

Bacteria that can multiply in stored, refrigerated blood are the ones most likely to cause transfusion-transmitted sepsis. Yersinia enterocolitica is a psychrotrophic Gram-negative rod, meaning it can grow at refrigerator temperatures (around 0–4°C). If contaminated blood is kept cold and then transfused, this organism can multiply and release endotoxins (LPS), leading to endotoxic shock in the recipient. Among the options, Yersinia enterocolitica best fits the scenario of endotoxic shock following refrigerated blood transfusion because of its ability to grow at cold temperatures and cause septicemia. The other organisms listed do not have the same strong association with refrigeration-enabled growth and transfusion-transmitted sepsis.