Premium
Evaluation of two detection methods of microorganisms in platelet concentrates
Author(s) -
Albertoni G.,
Andrade S. S.,
Araújo P. R. B.,
Carvalho F. O.,
Girão M. J. B. C.,
Barreto J. A.
Publication year - 2011
Publication title -
transfusion medicine
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.471
H-Index - 59
eISSN - 1365-3148
pISSN - 0958-7578
DOI - 10.1111/j.1365-3148.2011.01105.x
Subject(s) - serratia marcescens , microbiology and biotechnology , staphylococcus epidermidis , bacteria , polymerase chain reaction , staphylococcus aureus , real time polymerase chain reaction , microbiological culture , gold standard (test) , colony forming unit , biology , 16s ribosomal rna , staphylococcus , gram positive bacteria , escherichia coli , chromatography , chemistry , medicine , antimicrobial , biochemistry , genetics , gene
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.