Differential detection of rhinoviruses and enteroviruses RNA sequences associated with classical immunofluorescence assay detection of respiratory virus antigens in nasopharyngeal swabs from infants with bronchiolitis

Abstract

To define the role of enteroviruses and human rhinoviruses as etiological agents in childhood bronchiolitis, clinical aspirates from 84 infants admitted to hospital with symptoms of obstructive bronchiolitis were tested by picornavirus RT-PCR assay, adenovirus PCR assay and classical immunofluorescence antigen detection of common respiratory viral agents. Respiratory syncytial viruses (A&B) were detectable in 45 of 84 (53.6%) nasopharyngeal aspirates from infants with bronchiolitis, whereas coronaviruses, influenza viruses, and parainfluenza viruses were not detectable in the same samples. Adenoviruses were detectable by PCR in 11 of 84 (13.1%) nasopharyngeal swabs. By using a picornavirus RT-PCR assay followed by a differential molecular hybridisation, rhinovirus and enterovirus RNA sequences were detected in 16 of 84 (19%) and in 10 of 84 (11.9%) of the nasopharyngeal swabs tested. Positive human rhinovirus or enterovirus RT-PCR assay, however, was the only evidence of respiratory infection in 8 of 84 (9.5%) and in 7 of 84 (8.33%) of the studied patients. Respiratory syncytial viruses, human rhinoviruses, adenoviruses, and enteroviruses occur in dual infections detected in 18 of 84 (21.4%) respiratory samples tested. The median duration of stay in hospital was not significantly different between the patients demonstrating a single viral infection and those with a dual viral infection (6.22 +/- 2.07 vs. 5. 04 +/- 0.95 days; P > 0.05). In summary, combination of molecular and classical detection assays of common viruses can be used to demonstrate enterovirus and human rhinovirus respiratory infection in childhood bronchiolitis, and provides an improved approach to obtain new insights into concomitant viral respiratory tract infection in infants.

Bronquiolite aguda por rinovírus em lactentes jovens

“…4,5,7,15 In this study, RV was the second most common agent detected in the respiratory secretions (17% of cases) of infants hospitalized for AB, which is a frequency that is comparable with the studies mentioned. Furthermore, we have demonstrated that RV can be solely detected in infants with AB in the first months of life, as can be observed by the ages of the patients studied (median: 2 months of age).…”

“…2,5,14,16 An association of infections by RV and RSV in infants has been demonstrated before. 4,5,7,14 Indeed, Papadopoulos et al 5 found an association between the presence of both agents with the severity of AB episodes. In this study we identified this combination in 4/6 cases of RV infection, corroborating the findings of Papadopoulos et al However, the restricted number of cases does not allow more detailed analyses of the association with severity of AB episodes.…”

“…[1][2][3] Over the last decade, other viruses have also been associated with this illness, including rhinovirus (RV), enterovirus, metapneumovirus and, more recently, coronavirus. [4][5][6][7][8] Rhinovirus is known to be the most common cause of upper airways infections in children. [9][10] Furthermore, upper airway infections by this virus have been associated with episodes of asthma exacerbation in older children and adults.…”

“…Previous studies have demonstrated an association between RV infection and wheezing in infants. 4,5,7,14,15 Despite this, the prevalence of RV in young infants hospitalized because of AB in particular has not been demonstrated.…”

Microarray-based detection and genotyping of viral pathogens

“…With PCR methods, because it is difficult to design compatible multiplex primer sets (3), the maximum number of viruses detectable in a single assay is relatively small (2). Moreover, unambiguous viral identification with degenerate PCR often is complicated by the existence of highly homologous relatives, and discrimination between viral subtypes or genera requires additional labor-intensive procedures such as restriction enzyme analysis, sequencing, or hybridization blotting of the PCR product (4)(5)(6)(7)(8). Perhaps most significantly, even the broadest multiplexing is inherently biased, requiring assumptions that ultimately restrict the possible outcome to the selected candidate viruses.…”