Abstract
Reports of transfusion-related bacterial infection have recently increased, although direct causality between patient infection and blood products has been proven in only few instances. Here, the authors report a case of sepsis caused by methicillin-sensitive Staphylococcus aureus (MSSA) contamination of platelet concentrate (PC). The 70-year-old patient concerned had aplastic anemia, and was receiving regular out-patient treatment at Aichi Medical University Hospital.
When his platelet count fell to 10,000/μl and hemoglobin to 7.9g/dl, he was transfused with ten units of PC and two units of RBC. Fifteen minutes after the beginning of RBC transfusion, he developed a fever (40.7°C) and mild dyspnea, and was admitted as an in-patient, receiving medication, including antibiotics, in a Clean Room. Although vital signs were stable (systolic blood pressure: 130mmHg; fever: 38-39°C; SaO2:97%), he died unexpectedly the following morning. His family refused autopsy.
After he had developed fever and chills, his blood tests and blood culture had been examined. Additionally, blood samples in the PC bag, the segment tube and the RBC bag were subjected to blood culture. He was found to be leukocytopenic (WBC: 300/μl), and his blood yielded Staphylococcus aureus. Blood taken from the PC bag and the segment tube similarly developed Staphylococcus aureus, while no bacteria were detected from the RBC bag. Drug sensitivity testing of the three strains proved them to be MSSA, and the coagulase test and DNA analysis showed them to be identical, revealing that the sepsis was caused by MSSA contamination of the PC. Thus, when bacterial infection by blood products is suspected, blood culture should be examined not only for patient blood, but also relevant bags or segment tubes. It is necessary to prevent contamination of blood products by bacteria such as Staphylococcus residing in the skin, especially regarding PC, which is primarily kept at room temperature.
