Comparing Nose-Throat Swabs and Nasopharyngeal Aspirates Collected From Children With Symptoms for Respiratory Virus Identification Using Real-Time Polymerase Chain Reaction

MBBS, Queensland Paediatric Infectious Diseases Laboratory, Royal Children's Hospital, Herston Queensland 4029, Australia.
PEDIATRICS (Impact Factor: 5.47). 10/2008; 122(3):e615-20. DOI: 10.1542/peds.2008-0691
Source: PubMed


The objective of this study was to calculate sensitivity values for the detection of major respiratory viruses of childhood by using combined nose-throat swabs and nasopharyngeal aspirates.
Children who had symptoms and presented to a pediatric teaching hospital and had a diagnostic respiratory specimen collected were enrolled, and paired nose-throat swab and nasopharyngeal aspirate specimens were collected. Parents were asked to collect the nose-throat swab specimen in the first instance but could defer to a health care worker if unwilling. Nose-throat swab collectors were asked to rate perceived quality of collection. All nasopharyngeal aspirates were collected by a health care worker by using a standard protocol. Real-time polymerase chain reaction for 8 respiratory viruses was performed in our hospital's diagnostic laboratory.
Paired nose-throat swab/nasopharyngeal aspirate specimens were collected during 303 illnesses, with at least 1 respiratory virus identified in 186 (61%). For the major pathogens of childhood, influenza A virus and respiratory syncytial virus, collection by using the nose-throat swab had a sensitivity of 91.9% and 93.1%, respectively. A health care worker collected 219 (72%) of the nose-throat swab specimens; concordance with the nasopharyngeal aspirate was not related to health care worker collection or perceived quality of collection.
Nose-throat swab specimens, in combination with sensitive molecular testing, are a less invasive diagnostic respiratory specimen with adequate sensitivity for use in the clinic and hospital outpatient settings and large-scale community studies through parent collection. For children who present to a hospital in which an avian or pandemic strain of influenza virus is reasonably part of the differential diagnosis, nasopharyngeal aspirates or a similar collection technique (eg, nasal washes) should continue to be used.

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Available from: Theodorus P. Sloots, Aug 14, 2014
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    • "Importantly, when using highly sensitive polymerase chain reaction (PCR) assays the detection rates for respiratory viruses are similar in both anterior nasal swab specimens and samples collected by the more traditional method of nasopharyngeal aspiration [18,19]. Building on this information, later studies have also shown that PCR testing for respiratory viruses provided similar results for parent-collected anterior nasal swab specimens and either nasal swab or nasoparyngeal aspirates collected by healthcare professionals [16,17]. "
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    • "Infectious disease diagnostics traditionally rely heavily on pathogen detection [1], [2], [3]. However, the development of reproducible means for extracting RNA from whole blood, coupled with advanced statistical methods for analysis of complex datasets, has created the possibility of classifying infections based on host gene expression profiling. "
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    PLoS ONE 01/2013; 8(1):e52198. DOI:10.1371/journal.pone.0052198 · 3.23 Impact Factor
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    • "Data analysis We performed descriptive analyses of demographic and clinical data and are presented as proportions of all participants or all paired specimens collected. Given the sensitivity and specificity of real-time PCR diagnosis, we considered a specimen from either nostril positive for any virus to represent a true-positive, similar to previous studies (Lambert et al. 2008b; Meerhoff et al. 2010). This approach means that the specificity of either specimen type for any virus will be, by definition, 100%. "
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