Nucleic acid tests helpful in identifying respiratory viruses, but caution urged
Nucleic acid tests may offer some advantages over other methods in identifying respiratory viruses in children, according to study results published online.
Sonali Advani, MBBS, MPH, who is with the division of pediatric infectious diseases at the Johns Hopkins Children’s Center in Baltimore, and colleagues looked retrospectively at data on about 300 children who were admitted between December 2007 and March 2008.
The researchers reported that the nucleic acid tests were better at identifying viruses over other methods such as direct fluorescent antibody, tube culture and immunochromatography when examining the 148 children with confirmed respiratory symptoms.
“Nucleic acid tests have significantly advanced our ability to detect respiratory viruses in children. However, our finding of a positive nucleic acid tests in 41% of patients without respiratory symptoms should encourage clinicians to interpret positive results carefully,” the study’s lead investigator, Aaron Milstone, MD, MHS, told Infectious Diseases in Children.
In the remaining study sample, or the 158 children who did not have respiratory symptoms, the nucleic acid tests were positive for a virus in 42[AM1] % vs. 4% positivity using other testing methods. Advani and colleagues said, “Given the high prevalence of positive results in children without [respiratory virus infection] [AM2] symptoms, all results should be interpreted cautiously.”
The researchers wrote that that getting better methods to detect respiratory viruses is important because of the spectrum of clinical manifestations of different viral illnesses.
Because the tests identified a high number of respiratory infections, even in those children who were asymptomatic, the researchers encouraged future studies on “defining cut-off values that aid with interpreting positive results with more accuracy and reliability.”
Disclosure: Dr. Milstone receives grant support from Sage Products and BioMerieux. Dr. Advani reports no relevant financial disclosures.