Isolation of Streptococcus bovis from apheresis platelets of asymptomatic donor warranted colonoscopy investigation: case report and literature review.

ABSTRACT

BACKGROUND: Bacterial contamination of platelet (PLT) products is one of the most serious complications of transfusion. Culturing PLT components may detect the presence of bacteria, thus reducing the risk of a septic result after transfusion. Streptococcus bovis has previously been reported as a contaminating microorganism in PLT products. Here we report an asymptomatic donor diagnosed with occult colon malignancy after positive isolation of S. bovis from his apheresis PLTs (APs). We also review previous cases. CASE REPORT The PLT donor was a 50-year-old man with more than 150 prior plateletpheresis or whole blood donations. Bacterial culture of his AP components yielded two positive results: group D Streptococcus was isolated in July 2008 and S. bovis was reported in April 2010. The donor received further testing, and colonofibroscopic examination revealed colonic neoplasm. Pathologic examination of the biopsied tissue led to a diagnosis of invasive adenocarcinoma. He underwent a left hemicolectomy in July 2010. Examination of the resection specimen confirmed adenocarcinoma, Stage III with regional lymph node metastatic adenocarcinoma. CONCLUSION: Donated AP products positive for S. bovis should not be presumed to be due to contamination during collection. This bacteremia originating from donor factors needs to be carefully evaluated. Colonofibroscopic examination is recommended for these donors to detect colonic malignancy as early as possible.