Rapid detection and ruling out of neonatal sepsis by PCR coupled with Electrospray Ionization Mass Spectrometry (PCR/ESI-MS)

Abstract

Background: Sepsis is an important cause of morbidity and mortality in neonates and clinicians are typically required to administer empiric antibiotics while waiting for blood culture results. However, prolonged and inappropriate use of antibiotics is associated with various complications and adverse events. Better tools to rapidly rule out bacterial infections are therefore needed.

Aims: We aimed to assess the negative predictive value of PCR coupled with Electrospray Ionization Mass Spectrometry (PCR/ESI-MS) compared to conventional blood cultures in neonatal sepsis.

Study design: Prospective observational study.

Subjects: All consecutive neonates (<28days old) with clinical suspicion of sepsis. Samples for PCR/ESI-MS analysis were collected at the same time as samples for the blood culture, before the initiation of antibiotics.

Outcome measures: Our primary objective was to evaluate the negative predictive value of PCR/ESI-MS for the detection of bacteria in the bloodstream of newborns with suspected sepsis. Our secondary objective was the evaluation of the sensitivity, specificity and positive predictive value of the PCR/ESI-MS in such a neonatal population.

Results: We analysed 114 samples over 14months. The median age and weight were 32weeks+3days and 1840g, respectively. Two patients had negative PCR/ESI-MS results, but positive blood cultures. Overall, the negative predictive value was 98% (95%CI: 92% to 100%).

Conclusions: Based on these results, PCR/ESI-MS analysis of blood samples of neonates with suspected sepsis appears to have a very good negative predictive value when compared to blood cultures as gold standard. This novel test might allow for early reassessment of the need for antibiotics.

Keywords: Blood culture; Neonate; PCR coupled with electrospray ionization mass spectrometry (PCR/ESI-MS); Sepsis.