Incremental value of multiplex real-time PCR for the early diagnosis of sepsis in the emergency department.

BACKGROUND Delayed recognition of sepsis and inappropriate initial antibiotic therapy are associated with increased mortality and morbidity. The early detection of the causative organism in sepsis is an unmet clinical need. A novel multiplex real-time polymerase chain reaction (MRT-PCR) (SeptiFast®) technique may provide the microbiological diagnosis within six hours. METHODS We assessed the diagnostic accuracy of blood cultures and MRT-PCR in a comparative diagnostic cohort study in 110 consecutive adult patients presenting to the emergency department (ED) with suspected sepsis. RESULTS We collected 205 corresponding PCR samples and blood culture (BC) pairs from the 110 patients. There was moderate to high concordance between PCR and BC with 181 (88%) matching and 24 (12%) mismatching samples. The diagnostic accuracy of MRT-PCR in detecting sepsis and its causative organism was comparable to that of BCs. The additional use of MRT-PCR significantly reduced the time to microbiological diagnosis as compared to the use of conventional microbiological methods alone (mean time gained 3.9 hours, range 0-66 hours, p <0.001). CONCLUSION Diagnostic accuracy of BCs and MRT-PCR in the early diagnosis of sepsis and its causative organism in the ED are comparable. However, MRT-PCR reduces the time to microbiological diagnosis. Whether a more rapid detection of the organism by MRT-PCR could improve the outcome of patients has to be assessed in large prospective randomised trials.