Abiotrophia was previously referred to as nutritionally variant streptococci (NVS). In 1995 Kawamura et al. proposed the new genus Abiotrophia and the species Abiotrophia defectiva. Abiotrophia means life nutrition deficiency and therefore the growth requires supplemented nutrients or the presence of other helper bacteria that supply needed micronutrients1.
Abiotrophia is not able to grow in standard media and it is difficult to check by microscopy due to its Irregularities and variability in the shape and size of cells, so cases of Abiotrophia infection are likely misdiagnosed as culture-negative infections. The infections caused by Abiotrophia defective are likely under-recognized as more and more Abiotrophia defective have been reported in endocarditis (infection of the heart’s lining), knee prosthesis infection, and bacteremia2–4. The fastidious nature of Abiotrophia and the diagnosis difficulty often lead to culture-negative misdiagnosis. Molecular diagnostics has therefore become a useful tool for the rapid and accurate detection of Abiotrophia defectiva in infections.
Real-time PCR provides quick results but can have specificity challenges due to potential cross-reactivity in genetically similar regions. Rare cases of cross-reactivity between Abiotrophia and other bacteria like staphylococci or streptococci are reported using commercially available real-time PCR panels5. The development team behind the Unyvero System from Curetis took significant care to prevent cross-reactivity, a common issue that can compromise diagnostic accuracy. Unyvero employs a highly sequence-specific endpoint PCR followed by a hybridization process using multiple probes. This is further enhanced by a subsequent confirmation of specificity through melting curve analysis. This layered approach enables the Unyvero System to achieve extraordinary specificity in pathogen detection and demonstrate superior specificity in distinguishing between Streptococci and Abiotrophia in the Implant & Tissue Infection (ITI) panel6. Check the Unyvero ITI panel for more details.
1. Madison, G., Golamari, R., Bhattacharya, P., Madison, G., Golamari, R., and Bhattacharya, P. (2018). Endocarditis Caused by Abiotrophia and Granulicatella Species. In Advanced Concepts in Endocarditis (IntechOpen). https://doi.org/10.5772/intechopen.74252.
2. Senn, L., Entenza, J.M., Greub, G., Jaton, K., Wenger, A., Bille, J., Calandra, T., and Prod’hom, G. (2006). Bloodstream and endovascular infections due to Abiotrophia defectiva and Granulicatella species. BMC Infect Dis 6, 9. https://doi.org/10.1186/1471-2334-6-9.
3. Kim, S.H., Erikson, A., Woodfield, D., and DeMott, C. (2023). A Rare Case of Abiotrophia Endocarditis-Associated Glomerulonephritis Mimicking ANCA Vasculitis. J GEN INTERN MED 38, 806–809. https://doi.org/10.1007/s11606-022-07960-0.
4. Cassir, N., Grillo, J.-C., Argenson, J.-N., Drancourt, M., and Levy, P.-Y. (2011). Abiotrophia defectiva knee prosthesis infection: A case report. Journal of Medical Case Reports 5, 438. https://doi.org/10.1186/1752-1947-5-438.
5. Dumm, R.E., Wing, A., Richterman, A., Jacob, J., Glaser, L.J., and Rodino, K.G. (2021). The Brief Case: A Variant on a Classic-Abiotrophia defectiva Endocarditis with Discitis. J Clin Microbiol 59, e0309320. https://doi.org/10.1128/JCM.03093-20.
6. Suren, C., Feihl, S., Cabric, S., Banke, I.J., Haller, B., Trampuz, A., von Eisenhart-Rothe, R., and Prodinger, P.M. (2020). Improved pre-operative diagnostic accuracy for low-grade prosthetic joint infections using second-generation multiplex Polymerase chain reaction on joint fluid aspirate. International Orthopaedics (SICOT) 44, 1629–1637. https://doi.org/10.1007/s00264-020-04552-7.