Rapid recognition of bacteremia in humans using atmospheric pressure chemical ionization mass spectrometry of volatiles emitted by blood cultures

Abstract

Rapid recognition of pathogenic bacteria in humans is a serious problem in clinical research. In this six-month study, molecular volatiles of blood cultures from 61 patients with a suspicion of bacteremia and 39 patients positively diagnosed with bacteremia were fingerprinted by atmospheric pressure chemical ionization mass spectrometry (APCI-MS) for the presence of five common pathogens (Staphylococcus aureus, Escherichia coli, Klebsiella pneumonia, Acinetobacter baumannii and Pseudomonas aeruginosa) which statistically account for ca. 50% of cases of bacteremia in humans. All the infected blood cultures revealed characteristic and clearly distinct MS patterns specific to the presence of one of the five pathogens after an incubation time of 3–16 h. Technical replicates were incubated over 2–3 days for reference diagnosis using traditional blood culture detection. Overall, the results of our six-month hospital screening show that APCI-MS of blood culture volatiles allows rapid, reliable and cost-efficient diagnosis of bacteremia in humans. The integration of this approach in clinical practice will be further promoted by the growing availability of atmospheric pressure ionization mass spectrometers in bioanalytical laboratories and core facilities.