Platelet Transfusions Linked To Cases of Sepsis, At Least One Death, CDC Warns

At least four people developed sepsis infections last year after receiving platelet transfusions contaminated with bacteria, according to federal health regulators.

In the Morbidity and Mortality Weekly Report issued by the U.S. Centers for Disease Control and Prevention (CDC) this week, researchers warn that blood platelet transfusions caused patients to experience sepsis infection. While the patients received platelets from different blood sources, they each had another common source.

The infections occurred from May to October 2018, each involving a transfusion for a different reason, such as for leukemia or cirrhosis. After receiving the transfusions, the patients begin exhibiting signs of sepsis.

Later, samples indicated the platelets were contaminated with Acinetobacter calcoaceticus-baumannii or Staphylococcus saprophyticus. One patient died as a result of the infection.

Platelets are small cell structures needed for blood clotting. They can be collected from donors and transferred to a patient. During the transfusion the donor’s blood is drawn into a machine that separates the cells and extracts the platelets, called an apharesis machine. This returns the remaining blood to the donor and transfers the platelets to the receiving patient.

While the CDC report indicated the apheresis machines were made by the same manufacturer, the investigation is ongoing. The CDC would not release the name of the manufacturer and has not identified the contamination source.

Platelet bacterial contamination isn’t common. It occurs in only one in 5,000 platelet units, but is a serious risk to transfusion recipients because it can lead to sepsis, which can be fatal. Researchers warn that sepsis still can occur even when steps are taken to mitigate bacterial contamination.

An investigation by the CDC did not lead to a clear source of the contamination, however it did suggest that the bacteria found were closely related, suggesting the contamination may be from a common source. All of the collection sets used with the apheresis machines came from the same manufacturer. Two of three sets came from the same lot.

Sepsis occurs when an infection in the bloodstream triggers other immune responses throughout the body causing tissue damage, organ failure, and death. It can begin with the chills and lead to fever and a drop in blood pressure, eventually leading to more serous outcomes which can be fatal.

There is always a risk of contamination with blood products because they are stored at room temperature which can allow pathogens to form. However, modern screening methods have helped to reduce the risk.

The CDC report warned doctors to monitor patients for sepsis after platelet transfusions, even after bacterial mitigation steps have been taken. The CDC indicates they should focus on recognizing unusual side effects to help treat a patient rapidly and report the side effects to the CDC.