Torque Teno Virus in Nasopharyngeal Aspirate of Children With Respiratory Infections

Torque teno virus (TTV) is responsible for persistent infections and is considered a marker of immune function. The role of TTV as a facilitator of respiratory infections(RIs) is unknown. We aimed to estimate the prevalence of TTV in the nasopharyngeal aspirate (NPA) of hospitalized children with RIs and correlate them with outcomes and immune response. NPA was taken for testing 16 respiratory viruses by RT-polymerase chain reaction (PCR), TTV PCR, and immunological study.Sixty hospitalized children with an RI and 3 healthy control infants were included. A total of 51/60 patients had a positive common respiratory viral (CRV) identification. A total of 24/63 (38.1%) children were TTV+ and had other CRVs in 95.8% of cases vs 74.4% in TTV- (p=0.029). TTV+ patients tended to be older, have fever, and need PICU admission more often than TTV- patients. Abnormal chest X-ray was more frequent in the TTV+ patients, OR 2.6(95% CI:1.3-5.2).The genetic expression of filaggrin (involved in epithelial barrier integrity) was lower in TTV+ patients; however, levels of filaggrin in the NPA were increased.In summary, TTV infection is common in children with RI and could be associated with pneumonia, greater severity, and alteration in filaggrin gene expression and protein release.

Diagnosis of SARS-CoV-2 in children: accuracy of nasopharyngeal swab compared to nasopharyngeal aspirate.

The tests currently used for the direct identification of SARS-CoV-2 include specimens taken from upper and lower respiratory tract; recommendations from Word Health Organization prioritise nasopharyngeal swab (NS). In literature there are not available paediatric studies about the identification of SARS-CoV-2 through nasopharyngeal aspirate (NPA), but the use of NPA is deemed to be better than NS to identify respiratory viruses in children. The aim of our study is to evaluate diagnostic performances of NS compared to NPA for the detection of SARS-CoV-2 in children. We collected 300 paired samples (NS and NPA) from children hospitalized and followed up in our paediatric unit. We calculated the sensitivity and specificity of NS referred to NPA of the whole sample and then, considering both the age (≥ and < 6 years old) and the period of collection (March vs follow up) as covariates in different analysis. The NS has a low sensitivity in detecting SARS-CoV-2 in children when referred to NPA; whereas its specificity results high. In children under 6 years of age, our results suggest to prefer the collection of NS, whenever possible. Though statistically not significant, the sensitivity of NS becomes higher if it is performed before NPA.

Is nasopharyngeal swab comparable with nasopharyngeal aspirate to detect SARS-CoV-2 in children?

The tests currently used for the direct identification of SARS-CoV-2 include specimens taken from the upper and the lower respiratory tract.In our paediatric department all children undergo both nasopharyngeal swab and nasopharyngeal aspirate, performed from both nostrils, on admission and after 24 hours.We decided to compare these two methods of detection of SARS-CoV-2. Considering nasopharyngeal aspirate as the gold standard, we calculated sensitivities and specificities of nasopharyngeal swab.Based on our results, we suggest to prefer the collection of aspirates whenever possible.

Etiology of community-acquired pneumoniae according to results of molecular-genetic and bacteriological studies of nasopharyngeal swabs of sick people

The etiology of community-acquired pneumoniae (CAP) was evaluated according to the results of molecular-genetic and bacteriological researches of nasopharyngeal aspirate from 405 patients. According to molecular genetic studies, S. pneumoniae and M. pneumoniae are most frequently isolated from patients with CAP, and more often in children than in adults. Associations of microorganisms have been identified, among which S. pneumoniae occupies a leading position. According to bacteriological studies, S. pneumoniae is frequently isolated from patients with CAP, although the bacteriological method is not very effective.

The relationship between rhinovirus infection and acute wheezing in young children with recurrent wheezing

Asthma is a common chronic respiratory disease in childhood. The present study aims to assess the association between rhinovirus (RV) infection and acute wheezing in the occurrence of recurrent wheezing in 5-year old and younger children. A total of 109 children with recurrent wheezing and 70 children without wheezing (controls) were recruited from October 2013 to March 2015. Nasopharyngeal aspirate samples were obtained from all children. RV, human metapneumovirus (hMPV), and bocavirus (BoV) were tested by reverse transcription-polymerase chain reaction.Respiratory syncytial virus (RSV), parainfluenza virus (PIV), influenza virus (IV), and adenoviruses (ADV) were confirmed by detection of viral antigens via fluoroimmunoassay. Viral infection was more commonly detected in children with recurrent wheezing than in controls (odds ratio (OR): 6.10; 95% confidence interval (CI): 2.89–12.87). RV and RSV were found in both wheezing children and controls. However, RV was detected more in wheezing children than in controls (OR: 3.07; 95% CI: 1.37–6.90), followed by RSV (OR: 5.33; 95% CI: 1.53–18.62). Furthermore, RV more tended to infect wheezing children after infancy. Compared with children infected with other viruses, higher levels of eosinophil were found in wheezing children with RV infection ( P < 0.05). RV was the main pathogen that induced exacerbation in young children with recurrent wheezing. Furthermore, the rate of RV infection was higher in children above 1 year old. RV infection might be associated with high levels of eosinophil.