Identification of upper respiratory bacterial pathogens with the electronic nose.

OBJECTIVE To use an electronic nose to identify common upper respiratory bacterial pathogens. STUDY DESIGN Controlled in vitro analysis. METHODS Swabs of bacteria were obtained from in vitro samples. The specimens were vaporized and analyzed over the organic semiconductor-based electronic nose (Cyranose 320). Data from the 32-element sensor array were subjected to principal component analysis for depiction in two-dimensional space and differences in odorant patterns were assessed by calculating Mahalanobis distances. RESULTS The electronic nose was able to distinguish between control swabs and bacterial samples. Furthermore, calculation of the Mahalanobis distances among the various bacteria demonstrated distinct odorant classes (Mahalanobis distance > or = 3). This demonstrates that the electronic nose could differentiate among various common bacterial pathogens of the upper respiratory tract, including Staphylococcus aureus, Streptococcus pneumoniae, Haemophilus influenza, and Pseudomonas aeruginosa. CONCLUSIONS The electronic nose represents a novel method to identify potential upper respiratory infections and to discriminate among common upper respiratory bacterial pathogens. This technology could provide a rapid means to identify organisms causing upper respiratory infections.