M Hong Nguyen1, Cornelius J Clancy2, A William Pasculle1, Peter G Pappas3, George Alangaden4, George A Pankey5, Bryan H Schmitt6, Altaf Rasool7, Melvin P Weinstein7, Raymond Widen8, Diana R Hernandez9, Donna M Wolk9, Thomas J Walsh10, John R Perfect11, Mollie N Wilson12, Eleftherios Mylonakis13. 1. University of Pittsburgh and University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (M.H.N., A.W.P.). 2. University of Pittsburgh, Pittsburgh, Pennsylvania (C.J.C.). 3. University of Alabama at Birmingham, Birmingham, Alabama (P.G.P.). 4. Henry Ford Health System, Detroit, Michigan (G.A.). 5. Ochsner Health System, New Orleans, Louisiana (G.A.P.). 6. Indiana University School of Medicine, Indianapolis, Indiana (B.H.S.). 7. Rutgers Robert Wood Johnson Medical School, New Brunswick, New Jersey (A.R., M.P.W.). 8. Tampa General Hospital, Tampa, Florida (R.W.). 9. Geisinger Health, Danville, Pennsylvania (D.R.H., D.M.W.). 10. Weill Cornell Medicine of Cornell University, NewYork-Presbyterian Hospital, New York, New York (T.J.W.). 11. Duke University, Durham, North Carolina (J.R.P.). 12. University of Pittsburgh Medical Center, Pittsburgh, Pennsylvania (M.N.W.). 13. Alpert Medical School of Brown University, Providence, Rhode Island (E.M.).
Abstract
Background: Blood cultures, the gold standard for diagnosing bloodstream infections (BSIs), are insensitive and limited by prolonged time to results. The T2Bacteria Panel (T2 Biosystems) is a direct-from-blood, nonculture test that identifies the most common ESKAPE bacteria (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli). Objective: To assess performance of the T2Bacteria Panel in diagnosing suspected BSIs in adults. Design: Prospective patient enrollment (8 December 2015 through 4 August 2017). Setting: Eleven U.S. hospitals. Patients: 1427 patients for whom blood cultures were ordered as standard of care. Intervention: Paired blood culture and T2Bacteria testing. Measurements: Performance of T2Bacteria compared with a single set of blood cultures in diagnosing proven, probable, and possible BSIs caused by T2Bacteria-targeted organisms. Results: Blood culture and T2Bacteria results were positive for targeted bacteria in 3% (39 of 1427) and 13% (181 of 1427) of patients, respectively. Mean times from start of blood culture incubation to positivity and species identification were 38.5 (SD, 32.8) and 71.7 (SD, 39.3) hours, respectively. Mean times to species identification with T2Bacteria were 3.61 (SD, 0.2) to 7.70 (SD, 1.38) hours, depending on the number of samples tested. Per-patient sensitivity and specificity of T2Bacteria for proven BSIs were 90% (95% CI, 76% to 96%) and 90% (CI, 88% to 91%), respectively; the negative predictive value was 99.7% (1242 of 1246). The rate of negative blood cultures with a positive T2Bacteria result was 10% (146 of 1427); 60% (88 of 146) of such results were associated with probable (n = 62) or possible (n = 26) BSIs. If probable BSIs and both probable and possible BSIs were assumed to be true positives missed by blood culture, per-patient specificity of T2Bacteria was 94% and 96%, respectively. Limitation: Low prevalence of positive blood cultures, collection of a single set of culture specimens, and inability of T2Bacteria to detect nontargeted pathogens. Conclusion: The T2Bacteria Panel rapidly and accurately diagnoses BSIs caused by 5 common bacteria. Primary Funding Source: T2 Biosystems.
Background: Blood cultures, the gold standard for diagnosing bloodstream infections (BSIs), are insensitive and limited by prolonged time to results. The T2Bacteria Panel (T2 Biosystems) is a direct-from-blood, nonculture test that identifies the most common ESKAPE bacteria (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Escherichia coli). Objective: To assess performance of the T2Bacteria Panel in diagnosing suspected BSIs in adults. Design: Prospective patient enrollment (8 December 2015 through 4 August 2017). Setting: Eleven U.S. hospitals. Patients: 1427 patients for whom blood cultures were ordered as standard of care. Intervention: Paired blood culture and T2Bacteria testing. Measurements: Performance of T2Bacteria compared with a single set of blood cultures in diagnosing proven, probable, and possible BSIs caused by T2Bacteria-targeted organisms. Results: Blood culture and T2Bacteria results were positive for targeted bacteria in 3% (39 of 1427) and 13% (181 of 1427) of patients, respectively. Mean times from start of blood culture incubation to positivity and species identification were 38.5 (SD, 32.8) and 71.7 (SD, 39.3) hours, respectively. Mean times to species identification with T2Bacteria were 3.61 (SD, 0.2) to 7.70 (SD, 1.38) hours, depending on the number of samples tested. Per-patient sensitivity and specificity of T2Bacteria for proven BSIs were 90% (95% CI, 76% to 96%) and 90% (CI, 88% to 91%), respectively; the negative predictive value was 99.7% (1242 of 1246). The rate of negative blood cultures with a positive T2Bacteria result was 10% (146 of 1427); 60% (88 of 146) of such results were associated with probable (n = 62) or possible (n = 26) BSIs. If probable BSIs and both probable and possible BSIs were assumed to be true positives missed by blood culture, per-patient specificity of T2Bacteria was 94% and 96%, respectively. Limitation: Low prevalence of positive blood cultures, collection of a single set of culture specimens, and inability of T2Bacteria to detect nontargeted pathogens. Conclusion: The T2Bacteria Panel rapidly and accurately diagnoses BSIs caused by 5 common bacteria. Primary Funding Source: T2 Biosystems.
Authors: Kristoffer Strålin; Richard E Rothman; Volkan Özenci; Kieron Barkataki; David Brealey; Neelam Dhiman; Lara Poling; Michael C Kurz; Ajit P Limaye; Frank LoVecchio; Kristin Lowery; Loren G Miller; Gregory J Moran; J Scott Overcash; Amisha Parekh; W Frank Peacock; Emanuel P Rivers; Matthew Sims; Amy M Stubbs; Martin Sundqvist; Måns Ullberg; Karen C Carroll Journal: J Clin Microbiol Date: 2020-08-24 Impact factor: 5.948