Proof of Concept Evaluation of a New Diagnostic POCT Device for Culture- Independent Microbiological Diagnosis of Infective Endocarditis

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/nƚƌŽĚƵĐƟŽn: Accurate and fast microbiological diagnosis of ŝnĨĞcƟvĞ ĞnĚŽcĂrĚŝƟƐ (IE) is of vital importance for ƉĂƟĞnƚ outcome. Material & Methods: Forty cƵůƚƵrĞͲnĞŐĂƟvĞ heart valves were evaluated with a new POCT mƵůƟƉůĞxͲWCZ cartridge (Unyvero™, CƵrĞƟƐ AG, Holzgerlingen, Germany), ĂĚvĞrƟƐĞĚ to detect several Gram ƉŽƐŝƟvĞͬnĞŐĂƟvĞ bacteria and fungi, together with several ĂnƟbŝŽƟc resistance genes. Those POCT results were compared to cŽnvĞnƟŽnĂů 16S rDNA PCR/sequencing results. Results: POCT mƵůƟƉůĞxͲWCZ was ƉŽƐŝƟvĞ in 13 cases. [Staphylococcus aureus (n=5), Enterococcus spp. / E. faecalis (n=5), ConS (n=1), Granulicatella adjacens (n=1), Abiotrophia adjacens (n=1)]. nƟbŝŽƟc resistances were found in 44 specimens, from which 2 specimens were without any pathogen ŝĚĞnƟĮcĂƟŽn͘ 16S rDNA PCR was ƉŽƐŝƟvĞ in 20 cases. CŽnƐĞcƵƟvĞ sequencing ŝĚĞnƟĮĞĚ those as Staphylococcus spp. (n=6), Enterococcus faecalis (n=4), Streptococcus spp. (n=4), Leifsonia shinshuensis (n=1), Granulicatella elegans / G. adjacens (n=2), Abiotrophia adjacens (n=1). One case was ƉŽƐŝƟvĞ in 16S PCR without any reliable signal in sequencing. When comparing both methods, ŝĚĞnƟĮcĂƟŽn was consistent in 9 cases and divergent in other 9 cases. Discussion: This POCT cartridge is easy to integrate into the daily microbiology laboratory work ŇŽw͕ and is less laborious than 16S sequencing PCR. For the ĂƉƉůŝcĂƟŽn in rŽƵƟnĞ IE diagnosis, the system needs to be ŽƉƟmŝnjĞĚ to include targets for viridans streptococci and HACEK group. In ĂĚĚŝƟŽn͕ problems with invalid resistance and pathogen target ĚĞƚĞcƟŽn need to be ĮxĞĚ by the producer. Conclusion: The analyzed POCT system might be a future ĚŝĂŐnŽƐƟc tool for IE ĚĞƚĞcƟŽn following assay ŽƉƟmŝnjĂƟŽn͘