my personal edition > respiratory infections > news


  E-Mail this DGDispatch to a colleague

DGDispatch

Rapid RSV Test Speeds Diagnosis, May Decrease Unnecessary Antibiotic Use: Presented at ICAAC

By Michael Smith

SAN DIEGO, CA-- October 3, 2002 -- A newly developed optical immunoassay test (OIA) may be a rapid alternative to conventional cell culture as a diagnostic tool for respiratory syncytial virus (RSV), according to research presented at the Interscience Conference on Antimicrobial Agents and Chemotherapy.

RSV causes about 70 percent of cases of bronchiolitis, the single most common cause of infant hospitalisation in the western world, according to Dr. Joel E. Mortensen of Cincinnati Children's Hospital, in Cincinnati, OH.

The symptoms of RSV – including runny nose, cough, low-grade fever, and wheezing – are non-specific, making a mis-diagnosis possible. In patients with underlying cardiopulmonary disease, RSV can be life-threatening. As well, there are specific treatments for RSV, and for other respiratory pathogens that may mimic RSV, so that rapid diagnosis is important to avoid treatment errors and inappropriate antibiotic use.

The study looked at 440 specimens collected at four sites; one part of the specimen was sent for cell culture and other was tested using the OIA (made by Thermo BioStar Inc., of Boulder, Colo.) The OIA results could be read after 15 minutes and then could be stored to be read again later if necessary.

The OIA test was positive for 109 specimens, while 85 specimens were positive for RSV by the cell culture method.


The discordant specimens were studied for RSV nucleic acid; 32 of the 37 discordant specimens were available for this secondary analysis and RSV nucleic acid was found in 25.

Overall, Dr. Mortensen said, the study showed that the OIA test demonstrated a sensitivity of 88 percent, and a specificity of 96 percent. Positive and negative predictive values were 89 and 96 percent respectively.

But he said more study may be needed to better define the accuracy of the OIA and to compare it to other rapid RSV tests.

E-Mail this DGDispatch to a colleague

To print, use this version