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Background: The performance of a bacterial 16S ribosomal DNA real-time polymerase chain reaction (PCR) assay was evaluated and validated with an automated culture system to determine its use for screening of platelet concentrates (PCs)., Study Design and Methods: PCs were spiked with suspensions of Escherichia coli, Serratia marcescens, Staphylococcus epidermidis and St. aureus at 1, 10, and 100 colony-forming units (CFUs) mL and stored for 5 days. DNA amplification was performed using real-time PCR. The BacT/ALERT was used as a reference method and samples were inoculated into an aerobic culture bottle; for the PCR assay, aliquots were drawn from all (spiked) PCs on days 0 to 5 of storage., Results: Real-time PCR detected only the gram-positive bacteria in PCs spiked with low bacterial titres (1 CFU mL) after 48 h; however, it was able to detect all positive samples in PCs spiked with 10 CFU mL of either gram-positive or gram-negative bacteria after 48 h. In addition, real-time PCR detected all positive samples in PCs spiked with high gram-positive bacterial titres (100 CFU mL) after 24 h. On the other hand, the BacT/ALERT system showed positive results in all samples within 24 h., Conclusion: The BacT/ALERT method is more sensitive and should continue to be the gold standard for identifying bacterial contaminations in blood samples. The real-time PCR approach can be used for the screening of PCs for microbial detection before they are released from blood centres or shortly before they are used in blood transfusion, and thus allow an extended shelf life of the platelets., (© 2011 The Authors. Transfusion Medicine © 2011 British Blood Transfusion Society.)

Unlabelled: Nucleic acid amplification testing (NAT) was recently recommended by Brazilian legislation and has been implemented at some blood banks in the city of São Paulo, Brazil, in an attempt to reduce blood-born transmission of human immunodeficiency virus (HIV) and hepatitis C virus., Objective: Manual magnetic particle-based extraction methods for HIV and HCV viral nucleic acids were evaluated in combination with detection by reverse transcriptase - polymerase chain reaction (RT-PCR) one-step., Methods: Blood donor samples were collected from January 2010 to September 2010, and minipools of them were submitted to testing. ELISA was used for the analysis of anti-HCV/HIV antibodies. Detection and amplification of viral RNA was performed using real-time PCR., Results: Out of 20.808 samples screened, 53 samples (29 for HCV and 24 for HIV) were confirmed as positive by serological and NAT methods., Conclusion: The manual magnetic bead-based extraction in combination with real-time PCR detection can be used to routinely screen blood donation for viremic donors to further increase the safety of blood products.