The novel nanodiagnostic panel T2Candida® (T2 Biosystems) may be helpful in reducing the length of empiric antifungal treatment (EAT) in patients with multiple risk factors for candidemia and severe sepsis or septic shock, according to data published in The Journal of Antimicrobial Chemotherapy.
A single-center prospective observational study was performed in patients with severe sepsis or septic shock and multiple risk factors for candidemia. A total of 46 patients received an echinocandin as EAT for a median duration of 7 days (interquartile range [IQR], 4-13 days).
Diagnostic blood cultures were negative in 31 patients, positive for bacteria in 14 patients, and positive for Candida albicans in 1 patient. The T2Candida test was negative in 37, invalid in 5, and positive in 4 patients.
The T2Candida test reduced time to a negative result by 5 days. The performance of T2Candida was as follows: sensitivity = 100 % (95% CI, 2.5% to 100%), specificity = 91.8% (95%CI, 78% to 98%), positive predictive value = 25% (95% CI, 0.63% to 80.6%), and negative predictive value = 100% (95% CI, 89.7% to 100%).
Limitations of this study include the single center design, the low prevalence of candidemia (2.2%), and the poor sensitivity of blood cultures to detect invasive Candida. In addition, T2Candida samples were taken a median of 5.1 hours (IQR 2-15 hours) after drawing blood culture and EAT onset, which could have affected the availability of circulating fungal cells.
However, investigators stated that large sample sizes for testing new diagnostics in hospital epidemiology “may not be realistic in terms of time and costs” and alternatives such as favouring known positives to assess sensitivity potentially introduces even larger biases.
Investigators concluded from this pilot study that “T2Candida may improve the management of candidemia by shortening times to detection and species identification compared with blood cultures.”
It may also be useful for antifungal stewardship purposes if future studies conclude that antifungal therapy can be discontinued based on negative T2Candida results.
Giannella M, Paolucci M, Roncarati G, et al. Potential role of T2Candida in the management of empirical antifungal treatment in patients at high risk of candidaemia: a pilot single-centre study [published online June 22 2018]. J Antimicrob Chemother. doi:10.1093/jac/dky247