LRT panel provides specificity similar to traditional cultures with faster turnaround time
The Curetis Unyvero Lower Respiratory Tract, or LRT, panel showed similar clinical sensitivity and specificity compared with conventional cultures for specimens in patients with suspected pneumonia, according to a recent study.
The study’s results were presented as a part of The American Society for Microbiology’s (ASM’s) Microbe 2020 virtual meeting.
“In microbiology, we’ve been heavily culture based for many years,” David T. Pride, MD PhD, associate professor of pathology and medicine and associate director of microbiology at the University of California, San Diego, told Healio. “One theme of the past 5 to 10 years has been a shift toward molecular microbiology. I think that studies like ours are really starting to indicate that some of these multipanel tests can provide similar results to culture, but in a much more compressed time frame.”
Interim results from OpGen’s Unyvero HPN panel for pneumonia demonstrated that the test was concordant with bacterial cultures for detecting organisms causing coinfection, with a turnaround time of only a few hours. In the present study, Pride and colleagues performed LRT panels and conventional respiratory cultures of 200 specimens from patients hospitalized with suspected pneumonia. The specimens they examined included sputum aspirates (induced or expectorated), tracheal aspirates (TAs) and bronchoalveolar lavages (BALs). The majority of the specimens tested came from individuals aged 61 to 70 years.
The LRT panel demonstrated a sensitivity of 92% and a specificity of 98% when compared with conventional cultures, but the LRT panel detected 69 additional pathogens, including Legionella, Haemophilus influenzae, Moraxella catarrhalis and others. Additionally, the researchers observed a turnaround time with the LRT Panel of 5.2 hours, compared with 2.8 days for a traditional respiratory culture.
“Based on the tight correlation between Unyvero LRT and culture results, rapid and reliable positive predictive value and negative predictive value of the Unyvero LRT panel can offer the potential for earlier, more appropriate antibiotic adjustment and therefore help improve antibiotic stewardship,” Oliver Schacht, PhD, CEO of OpGen, told Healio. “Pneumonia is a deadly condition with clinical outcomes that are highly dependent upon prompt and appropriate therapy. Standard culture methods for lower respiratory tract infections (eg, pneumonia) are too slow and insensitive to guide early clinical decisions concerning treatment selection and, potentially, required patient isolation.”
A similar study presented at ASM Microbe found that the Curetis panel and the BioFire FilmArray Pneumonia (FAP) panel were both sensitive tests for the detection of respiratory pathogens.
“While both panels detect the most common bacterial pathogens, each have unique features which can be useful in different clinical settings,” the researchers wrote.
Researchers in that study compared the panels by testing 120 samples, including 68 sputum, 37 BALs and 15 TAs; they excluded viral pathogens from their analysis.
The researchers found that the Curetis panel detected 82 pathogens and the FAP detected 95. Additionally, the sensitivity and specificity was 89% and 98%, respectively, for the Curetis panel and 95% and 98%, respectively, for the FAP panel.
Pride noted that it is imperative for physicians to be aware of organisms often missed by routine tests.
“We need to raise awareness that there are organisms out there, like Legionella, that are difficult to culture that physicians often times aren’t testing for — and that panels like this can detect them,” Pride said. “Physicians need to be vigilant in their thought process about whether or not this is an organism they should be looking for in all of their patients.”
- Ghadikolai A, et al. A comparison of two molecular panels for culture independent detection of lower respiratory tract pathogens. Presented at: ASM Microbe 2020; Virtual.
- Shin JH, et al. Comparison of the Curetis Unyvero and in the of . Presented at: ASM Microbe 2020; Virtual.