Electronic Nose in the Detection of Wound Infection Bacteria from Bacterial Cultures: A Proof-of-Principle Study

Abstract

Background: Soft tissue infections, including postoperative wound infections, result in a significant burden for modern society. Rapid diagnosis of wound infections is based on bacterial stains, cultures, and polymerase chain reaction assays, and the results are available earliest after several hours, but more often not until days after. Therefore, antibiotic treatment is often administered empirically without a specific diagnosis. Methods: We employed our electronic nose (eNose) system for this proof-of-concept study, aiming to differentiate the most relevant bacteria causing wound infections utilizing a set of clinical bacterial cultures on identical blood culture dishes, and established bacterial lines from the gaseous headspace. Results: Our eNose system was capable of differentiating both methicillin-sensitive Staphylococcus aureus (MSSA) and methicillin-resistant Staphylococcus aureus (MRSA), Streptococcus pyogenes, Escherichia coli, Pseudomonas aeruginosa, and Clostridium perfringens with an accuracy of 78% within minutes without prior sample preparation. Most importantly, the system was capable of differentiating MRSA from MSSA with a sensitivity of 83%, a specificity of 100%, and an overall accuracy of 91%. Conclusions: Our results support the concept of rapid detection of the most relevant bacteria causing wound infections and ultimately differentiating MRSA from MSSA utilizing gaseous headspace sampling with an eNose.

Modern Tools for Rapid Diagnostics of Antimicrobial Resistance

“…Saviauk et al performed an applicability test for the ChemPro 100i Ion Mobility Spectrometry sensor (Environics Inc.). They could discriminate MRSA from MSSA with 83% sensitivity and 100% specificity (Saviauk et al, 2018 ) and were able to identify also other pathogens ( P. aeruginosa, Enterococcus, E. coli , and Clostridium perfringens ) from culture plates with 78% accuracy. In order to access the AST market, the eNose systems should outperform the simple and inexpensive colorimetric sensor array system “Reveal-AST” (Specific Technologies, USA) which is applicable to growth-based AST.…”

Identification and Antibiotic‐Susceptibility Profiling of Infectious Bacterial Agents: A Review of Current and Future Trends

“…Remarkably, it differentiated MRSA from MSSA with 83% sensitivity, 100% specificity, and 91% overall accuracy. Although the number of strains evaluated was low (12 MRSA and 11 MSSA) this opens the possibility for future development as an AST technology. The same device was tested in urine samples from UTIs, and showed 95% sensitivity and 96% specificity in comparison with the reference method (urine cultures), allowing a high discriminatory power with E. coli , Klebisella spp.…”

Applications of Electronic-Nose Technologies for Noninvasive Early Detection of Plant, Animal and Human Diseases

“…The microbial cause of soft tissue wound infections, including post-operative wound infections, are conventionally based on identification of bacterial or fungal pathogens by swab cultures, microscopic examinations, laboratory tests and PCR assays which require several hours to days to obtain a diagnosis [217]. Consequently, broad-spectrum antibiotic treatment generally is administered early as a precautionary measure before a specific diagnosis.…”

“…The need for real-time, rapid and accurate diagnoses, allowing for more effective early targeted pathogen-specific treatments, require the development and use of methods for identifying pathogens much earlier based on chemical surveillance methods that detect the unique microbial metabolite signatures (VOC-profiles) produced by individual microbial species due to their particular use of specific combinations of metabolic pathways [10]. Saviauk et al [217] recently tested a handheld ion mobility spectrometry (IMS)-type e-nose device for POCT to rapidly differentiate between the most common SSTI and life-threatening pathogens causing gas gangrene infections. They examined the most relevant bacteria causing wound infections by analyzing gaseous headspace VOCs of clinical bacterial blood cultures on standardized culture media.…”