Detection of bacteraemia in critically ill patients using 16S rDNA polymerase chain reaction and DNA sequencing

Objective: To confirm the sensitivity of the polymerase chain reaction PCR) technique (versus blood cultures) and to gain a better understanding of the incidence of true- and false-positive results when using this technique. Design: Observational study. Setting: Fourteen-bed, level 3 intensive care unit. Patients: Hundred twenty-six critically ill adult patients. Hundred ninety-seven blood culture and PCR samples taken as clinically indicated for suspected sepsis, according to routine ICU protocol. Measurements and results: The PCR product (16SrDNA: 341F-1195R) was sequenced and compared with a database of known species (Gene-bank) to identify the bacterial nucleic acid. The PCR or blood culture result was classified as a true-positive if there was other microbiological or clinical supporting evidence.