Two cases of Streptococcus dysgalactiae subspecies equisimilis infection transmitted through transfusion of platelet concentrate derived from separate blood donations by the same donor

Abstract

AbstractBackgroundTransfusion‐transmitted bacterial infections (TTBIs) in Japan have been largely prevented due to a short shelf life of 3.5 days after blood collection for platelet concentrate (PC) and washed PCs (WPCs; PC in which 95% plasma is replaced by platelet additive solution).Case PresentationCase 1: In January 2018, a woman in her 50s with aplastic anaemia who received WPC transfusion and developed a fever the next day and Streptococcus dysgalactiae subspecies equisimilis (SDSE) was detected in the residual WPC. Case 2: In May 2018, a man in his 60s with a haematologic malignancy who received PC transfusion and developed chills during the transfusion. SDSE was detected in the patient's blood and residual PC.The contaminated platelet products were both manufactured from blood donated by the same donor. The multi‐locus sequencing typing revealed that SDSE detected in case 1 was identical to that from case 2; however, whole blood subsequently obtained from the donor was culture negative.ConclusionWPC and PC produced from two blood donated 106 days apart by the same donor were contaminated with SDSE of the same strain and both caused TTBIs. Safety measures should be considered regarding blood collection from a donor with a history of bacterial contamination.