All issues > Volume 38(11); 1995

Original Article

J Korean Pediatr Soc. 1995;38(11):1486-1497. Published online November 15, 1995.

Respiratory Syncytial Virus Infections and Application of Nested Reverse Transcription-Polymerase Chain Reaction

Kon-Hee KH Lee¹, Hae-Sun HS Yoon¹, Kyu-Man KM Lee², Kyung-Hee KH Kim³, Yang-Ja YJ Cho³

¹Department of Pediatrics, College of Medicine, Hallym University, Seoul, Korea
²Department of Clinical Pathology, College of Medicine, Hallym University, Seoul, Korea
³Department of Microbiology, School of Medicine, Hanyang University, Seoul, Korea

Abstract

Purpose
: Respiratory syncytial virus(RSV) in the most common cause of bronchiolitis and pneumonia in chileren less than 2 years old. Complications of RSV infections may be life-threatening in children who are immunosuppressed or who have congenital heart disease. Thus it is imperative that laboratory results be rapid and accurate. We therefore were interested in evaluating the role of RSV in the pediatric respiratory infections.
Methods
: Nasopharyngeal aspirates from 700 children (<4 years) with acute respiratory tract diseases in Seoul, Korea, during a 41-month period (from November 1990 through April 1994), were screened for RSV by an enzyme immunoassay(EIA) or cultu¡ⓒring in HEp-2 cells and nested reverse transcription-polymerase chain reaction (nRT¡ⓒ PCR).
Results
: RSV infections trended to peak during winter. RSV was the most common cause of the bronchiolitis in young infants (<12 months) and caused servere symptoms and signs of respiratory tracts such as dyspnea and chest retraction (respectively p<0.00l). Of the 700 nasopharyngeal aspirates, 623 were screened for the RSV by the EIA and the rest 77 by the cell cultrue and nRT-PCR. Of the 623 tested by the EIA, 189(30%) were positive. Among infants with bronchiolitis 36% yielded the RSV. Of the 77 aspirates, 27 samples were positive in culture and 22 were positive in the nRT-PCR. The test was 81.5% sensitive and 86.0% specific when compared with cell culture methods. In detecting RSV, the positivity decreased with EIA or cell culture when the nasopharyngeal secretions were collected after a week from the onset point of illness. To evaluate the efficacy of cell culture method, we tried to examine 19 children who had severe respiratory symptoms, with clinically suspected to have RSV infections, and negative RSV in cell culture methods. Three(30%) of 9 samples that had been negative for RSV in culture became positive by nRT-PCR. These nasopharyngeal aspirates were collected a week after the onset of illness.
Conclusion
: This study suggests that RSV cause severe respiratory tract diseases in Korean infants and children with a peak in winter. For any specimen collected after the acute period of illness (after a week from the onset point), nRT-PCR is recommended method for a RSV diagnosis.

Keywords :Respiratory syncytial virus, Nested Reverse Transcription-Polymerase Chain Reaction