The ubiquity of asymptomatic respiratory viral infections in the tonsils and adenoids of children and their impact on airway obstruction

Infants hospitalized with lower respiratory tract infections during the first two years of life have increased risk of pediatric obstructive sleep apnea

RATIONALE

Lower respiratory tract infections (LRTI) during the first 2 years of life increase the risk of pediatric obstructive sleep apnea (OSA), but whether this risk varies by LRTI severity is unknown.

METHODS

We analyzed data from 2962 children, aged 0-5 years, with early-life LRTI requiring hospitalization (severe LRTI, n = 235), treated as outpatients (mild LRTI, n = 394) and without LRTI (reference group, n = 2333) enrolled in the Boston Birth Cohort. Kaplan-Meier survival estimates and Cox proportional hazards models adjusted by pertinent covariables were used to evaluate the risk of pediatric OSA.

RESULTS

Compared to children without LRTI, those with mild LRTI were at a higher risk of having OSA (hazard ratio [HR] 1.44, 95% confidence interval [CI]: 1.01-2.05), and those with severe LRTI were at the highest risk (HR 2.06, 95% CI: 1.41-3.02), independently of relevant covariables (including maternal age, race, gestational age, and type of delivery). Additional risk factors linked to a higher risk of OSA included prematurity (HR 1.34, 95% CI 1.01-1.77) and maternal obesity (HR 1.82, 95% CI 1.32-2.52). The time elapsed between LRTI and OSA diagnosis was similar in mild and severe LRTI cases, with medians of 23 and 25.5 months, respectively (p = .803).

CONCLUSION

Infants with severe early-life LRTI have a higher risk of developing OSA, and surveillance strategies to identify OSA need to be particularly focused on this group. OSA monitoring should continue throughout the preschool years as it may develop months or years after the initial LRTI hospitalization.

Successful Antiviral Treatment for Chronic Adenoiditis Caused by Herpes Virus in a Pediatric Patient: A Case Report

BACKGROUND The adenoids are lymphatic tissue located in the nasopharynx and play a role in upper-airway immunity. Inflammation of the adenoids is called adenoiditis, which can cause a variety of symptoms. This is a common condition and is due to acute viral or bacterial infection. Most patients experience mild symptoms of upper-respiratory tract infection with a self-limiting course. CASE REPORT A 5-year-old female patient was brought into the clinic by her parents with concerns regarding hearing and sleep. Clinical assessment was consistent with persistent otitis media with effusion and sleep-disordered breathing. She was scheduled for surgery, including nasendoscopy, adenoidectomy, and bilateral grommet insertion. During surgery, direct visualization of the postnasal space showed complete obstruction by hypertrophic, inflamed adenoids covered in a thick, white film. A biopsy was taken, which detected herpes virus cytopathic effect. A diagnostic workup excluded a neoplastic process and other bacterial or fungal infections. A trial of oral antiviral medication was successful and follow-up nasendoscopy showed resolution of adenoid hypertrophy. CONCLUSIONS Direct visualization of the postnasal space, with a transoral mirror or 120-degree endoscope, prior to adenoidectomy can aid diagnosis. Adenoiditis may be caused by a wide range of organisms, including herpes virus. Active mucopurulent discharge should raise concern for infection by bacteria, fungi, or virus. Previous research on viral infection of the adenoids have been in asymptomatic patients with presumed latent infection and undergoing elective adenoidectomy. To our knowledge, this is the first paper to report on successful treatment with antiviral medication alone.

Tonsils are major sites of persistence of SARS-CoV-2 in children

In the present study, we show that SARS-CoV-2 can infect palatine tonsils, adenoids, and secretions in children without symptoms of COVID-19, with no history of recent upper airway infection. We studied 48 children undergoing tonsillectomy due to snoring/OSA or recurrent tonsillitis between October 2020 and September 2021. Nasal cytobrushes, nasal washes, and tonsillar tissue fragments obtained at surgery were tested by RT-qPCR, immunohistochemistry (IHC), flow cytometry, and neutralization assay. We detected the presence of SARS-CoV-2 in at least one specimen tested in 27% of patients. IHC revealed the presence of the viral nucleoprotein in epithelial surface and in lymphoid cells in both extrafollicular and follicular regions, in adenoids and palatine tonsils. Also, IHC for the SARS-CoV-2 non-structural protein NSP-16 indicated the presence of viral replication in 53.8% of the SARS-CoV-2-infected tissues. Flow cytometry showed that CD20+ B lymphocytes were the most infected phenotypes, followed by CD4+ lymphocytes and CD123 dendritic cells, CD8+ T lymphocytes, and CD14+ macrophages. Additionally, IF indicated that infected tonsillar tissues had increased expression of ACE2 and TMPRSS2. NGS sequencing demonstrated the presence of different SARS-CoV-2 variants in tonsils from different tissues. SARS-CoV-2 antigen detection was not restricted to tonsils but was also detected in nasal cells from the olfactory region. Palatine tonsils and adenoids are sites of prolonged RNA presence by SARS-CoV-2 in children, even without COVID-19 symptoms. IMPORTANCE This study shows that SRS-CoV-2 of different lineages can infect tonsils and adenoids in one quarter of children undergoing tonsillectomy. These findings bring advancement to the area of SARS-CoV-2 pathogenesis, by showing that tonsils may be sites of prolonged infection, even without evidence of recent COVID-19 symptoms. SARS-CoV-2 infection of B and T lymphocytes, macrophages, and dendritic cells may interfere with the mounting of immune responses in these secondary lymphoid organs. Moreover, the shedding of SARS-CoV-2 RNA in respiratory secretions from silently infected children raises concern about possible diagnostic confusion in the presence of symptoms of acute respiratory infections caused by other etiologies.

Adenoid hypertrophy-​diagnosis and treatment: the new S2k guideline

Hyperplasia of the pharyngeal tonsils is to be considered pathologic when nasopharyngeal symptoms of mechanical obstruction and/or chronic inflammation occur. Chronic Eustachian tube dysfunction can result in various middle ear diseases such as conductive hearing loss, cholesteatoma, and recurrent acute otitis media. During examination, attention should be paid to the presence of adenoid facies (long face syndrome), with a permanently open mouth and visible tip of the tongue. In the case of severe symptoms and/or failure of conservative treatment, adenoidectomy is usually performed on an outpatient basis. Conventional curettage remains the established standard treatment in Germany. Histologic evaluation is indicated for clinical evidence of mucopolysaccharidoses. Due to the risk of hemorrhage, the preoperative bleeding questionnaire, which is obligatory before every pediatric surgery, is referred to. Recurrence of adenoids is possible despite correct adenoidectomy. Before discharge home, otorhinolaryngologic inspection of the nasopharynx for secondary bleeding should be performed and anesthesiologic clearance obtained.

Unveiling the Enigmatic Adenoids and Tonsils: Exploring Immunology, Physiology, Microbiome Dynamics, and the Transformative Power of Surgery

Within the intricate realm of the mucosal immune system resides a captivating duo: the adenoids (or pharyngeal tonsils) and the tonsils (including palatine, tubal, and lingual variations), which harmoniously form the Waldeyer's ring. As they are strategically positioned at the crossroads of the respiratory and gastrointestinal systems, these exceptional structures fulfill a vital purpose. They function as formidable "gatekeepers" by screening microorganisms-both bacteria and viruses-with the mission to vanquish local pathogens via antibody production. However, under specific circumstances, their function can take an unsettling turn, inadvertently transforming them into reservoirs for pathogen incubation. In this review, we embark on a fascinating journey to illuminate the distinctive role of these entities, focusing on the local immune system inside their tissues. We delve into their behavior during inflammation processes, meticulously scrutinize the indications for surgical intervention, and investigate the metamorphosis of their microbiota in healthy and diseased states. We explore the alterations that occur prior to and following procedures like adenoidectomy, tonsillectomy, or their combined counterparts, particularly in pediatric patients. By comprehending a wealth of data, we may unlock the key to the enhanced management of patients with otorhinolaryngological disorders. Empowered with this knowledge, we can embrace improved therapeutic approaches and targeted interventions/surgeries guided by evidence-based guidelines and indications.

[Adenoids-diagnosis and treatment: the new German S2k guideline]

Hyperplasia of the pharyngeal tonsils is to be considered pathologic when nasopharyngeal symptoms of mechanical obstruction and/or chronic inflammation occur. Chronic Eustachian tube dysfunction can result in various middle ear diseases such as conductive hearing loss, cholesteatoma, and recurrent acute otitis media. During examination, attention should be paid to the presence of adenoid facies (long face syndrome), with a permanently open mouth and visible tip of the tongue. In the case of severe symptoms and/or failure of conservative treatment, adenoidectomy is usually performed on an outpatient basis. Conventional curettage remains the established standard treatment in Germany. Histologic evaluation is indicated for clinical evidence of mucopolysaccharidoses. Due to the risk of hemorrhage, the preoperative bleeding questionnaire, which is obligatory before every pediatric surgery, is referred to. Recurrence of adenoids is possible despite correct adenoidectomy. Before discharge home, otorhinolaryngologic inspection of the nasopharynx for secondary bleeding should be performed and anesthesiologic clearance obtained.

Is There an Association between Viral Infections and Risk for Pediatric Obstructive Sleep Apnea? A Systematic Review

(1) Background: Obstructive sleep apnea (OSA) affects approximately 1% to 5% of children. To date, the main pathophysiological factor is adenotonsillar tissue hypertrophy. As many respiratory viruses can persist in secondary lymphoepithelial organs after upper airway infection, the objective of this systematic review was to investigate the link between history of viral infections and the risk of pediatric OSA. (2) Methods: Corresponding references were searched electronically (PubMed [MEDLINE], Cochrane Library and Scopus) until 21 November 2022. Prospective or retrospective cohorts, evaluating the children suffering from OSA with history of viral infections and comparing them with children with no history of viral infections written in English, were included. Four independent reviewers selected studies, extracted data, and evaluated the risk of bias using ROBINS-I. (3) Results: Of 1027 potentially eligible articles, four studies (one retrospective, two prospective cohorts and one case-control) were included. (4) Conclusions: Exposure to lower airway infections may precede the diagnosis of pediatric OSA suggesting that respiratory viruses may play a mechanical role in the development of pediatric OSA. Further research is required to improve our understanding of the role of viral infections. Registration: PROSPERO CRD awaiting.

Persistence of RNA Viruses in the Respiratory Tract: An Overview

Respiratory RNA viruses are a major cause of acute lower respiratory tract infections and contribute substantially to hospitalization among infants, elderly, and immunocompromised. Complete viral clearance from acute infections is not always achieved, leading to persistence. Certain chronic respiratory diseases like asthma and chronic obstructive pulmonary disease have been associated with persistent infection by human respiratory syncytial virus and human rhinovirus, but it is still not clear whether RNA viruses really establish long-term infections as it has been recognized for DNA viruses as human bocavirus and adenoviruses. Herein, we summarize evidence of RNA virus persistence in the human respiratory tract, as well as in some animal models, to highlight how long-term infections might be related to development and/or maintenance of chronic respiratory symptoms.

Herpesvirus infections in adenoids in patients with chronic adenotonsillar disease

Adenoids and tonsils have gained interest as a new in vivo model to study local immune functions and virus reservoirs. Especially herpesviruses are interesting because their prevalence and persistence in local lymphoid tissue are incompletely known. Our aim was to study herpesvirus and common respiratory virus infections in nonacutely ill adenotonsillar surgery patients. Adenoid and/or palatine tonsil tissue and nasopharyngeal aspirate (NPA) samples were collected from elective adenoidectomy (n = 45) and adenotonsillectomy (n = 44) patients (median age: 5, range: 1–20). Real‐time polymerase chain reaction was used to detect 22 distinct viruses from collected samples. The overall prevalence of herpesviruses was 89% and respiratory viruses 94%. Human herpesviruses 6 (HHV6), 7 (HHV7), and Epstein–Barr virus (EBV) were found, respectively, in adenoids (33%, 26%, 25%), tonsils (45%, 52%, 23%), and NPA (46%, 38%, 25%). Copy numbers of the HHV6 and HHV7 genome were significantly higher in tonsils than in adenoids. Patients with intra‐adenoid HHV6 were younger than those without. Detection rates of EBV and HHV7 showed agreement between corresponding sample types. This study shows that adenoid and tonsil tissues commonly harbor human herpes‐ and respiratory viruses, and it shows the differences in virus findings between sample types.

Generation of human tonsil epithelial organoids as an ex vivo model for SARS-CoV-2 infection

The palatine tonsils (hereinafter referred to as "tonsils") serve as a reservoir for viral infections and play roles in the immune system's first line of defense. The aims of this study were to establish tonsil epithelial cell-derived organoids and examine their feasibility as an ex vivo model for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection. The tonsil organoids successfully recapitulated the key characteristics of the tonsil epithelium, including cellular composition, histologic properties, and biomarker distribution. Notably, the basal layer cells of the organoids express molecules essential for SARS-CoV-2 entry, such as angiotensin-converting enzyme 2 (ACE2), transmembrane serine protease 2 (TMPRSS2) and furin, being susceptible to the viral infection. Changes in the gene expression profile in tonsil organoids revealed that 395 genes associated with oncostatin M signaling and lipid metabolism were highly upregulated within 72 h after SARS-CoV-2 infection. Notably, remdesivir suppressed the viral RNA copy number in organoid culture supernatants and intracellular viral protein levels in a dose-dependent manner. Here, we suggest that tonsil epithelial organoids could provide a preclinical and translational research platform for investigating SARS-CoV-2 infectivity and transmissibility or for evaluating antiviral candidates.

Lower respiratory tract infections in early life are associated with obstructive sleep apnea diagnosis during childhood in a large birth cohort

STUDY OBJECTIVES

Several birth cohorts have defined the pivotal role of early lower respiratory tract infections (LRTI) in the inception of pediatric respiratory conditions. However, the association between early LRTI and the development of obstructive sleep apnea (OSA) in children has not been established.

METHODS

To investigate whether early LRTIs increase the risk of pediatric OSA, we analyzed clinical data in children followed during the first 5 years in the Boston Birth Cohort (n = 3114). Kaplan-Meier survival estimates and Cox proportional hazards models adjusted by pertinent covariates were used to evaluate the risk of OSA by the age of 5 years between children with LRTI during the first 2 years of life in comparison to those without LRTI during this period.

RESULTS

Early life LRTI increased the risk of pediatric OSA independently of other pertinent covariates and risk factors (hazard ratio, 1.53; 95% CI, 1.15 to 2.05). Importantly, the association between LRTI and pediatric OSA was limited to LRTIs occurring during the first 2 years of life. Complementarily to this finding, we observed that children who had severe respiratory syncytial virus bronchiolitis during infancy had two times higher odds of OSA at 5 years in comparison with children without this exposure (odds ratio, 2.09; 95% CI, 1.12 to 3.88).

CONCLUSIONS

Children with severe LRTIs in early life have significantly increased risk of developing OSA during the first 5 years of life. Our results offer a new paradigm for investigating novel mechanisms and interventions targeting the early pathogenesis of OSA in the pediatric population.

The investigation of bacterial adhesion of palatine tonsils epithelial cells in patient with infectious mononucleosis

Aim. To evaluate the features of pharynx tonsils mucous membrane colonization by pathogenic and opportunistic microorganisms by using the pharynx palatine tonsils epithelium electron microscopic examination of the patients with infectious mononucleosis and acute streptococcal tonsillitis. Materials and methods. Two patients – patient P., 12 years old with a confirmed diagnosis of infectious mononucleosis and patient A., 8 years old with confirmed acute streptococcal tonsillitis. The patients were taken a bacteriological examination of the mucus and epithelium scraping from the surface of the pharyngeal tonsils. Tissue samples were examined in the electron microscopy laboratory of the Lviv National University. Results and discussion. 36 tonsils epithelial tissue micro preparations of patient A. and 41 micro preparations of patient P. were studied. Streptococcus pyogenes, Str. pneumoniae, Str. viridans, Сandida albicans, as well as non-pathogenic bacteria: Diphtheroides sp., Neisseria sp., Corynebacterium spp. were identified as result of the patient P. bacteriological examination of mucus from the surface of the pharyngeal tonsils. Staph. aureus, Str. viridans, Str. pneumoniae were identified during a bacteriological examination of patient A. Eosinophils with a two-segmented nucleus, specific granularity, phagocytosed spherical bacteria in the cytoplasm were detected during the histological examination of the materials taken from the surface of the patient’s tonsils with acute tonsillitis. Research showed that bacteria were accumulated not only in the structure of extracellular detritus. Numerous bacteria accumulations were also found in the cytoplasm of the epithelial cells in the patient with infectious mononucleosis. The cell's shape looked like a bunch of grapes. Conclusions. The electron microscopic examination showed differences in the coccal flora localization: the extracellular localization of bacteria in the patient with acute bacterial tonsillitis and intraepithelial presence of the bacteria in the patient with tonsillitis during infectious mononucleosis were found.

Intratonsillar detection of 27 distinct viruses: A cross-sectional study

Palatine tonsils have been observed to harbor several distinct respiratory and herpesviruses in separate studies. In this study, the presence of these viruses in palatine tonsils was comprehensively studied in both children and adults. A cross-sectional analysis of 181 patients (median age 22 years; range, 2.6-66) operated for a benign tonsillar disease was conducted. Real-time polymerase chain reaction was performed to detect 27 distinct viruses in all: eight human herpesviruses, 16 respiratory viruses, parvo B19, and polyoma BK/JC viruses. Clinical characteristics of the patients and underlying conditions were evaluated. In total, 92% of patients had virus detected in tonsils (Epstein-Barr virus 72%, human herpesvirus 7, and 6B 54% and 16%, respectively, enterovirus 18%, parvovirus B19 7% and the rest <4%). No herpes simplex virus 2, varicella zoster virus, polyoma JC virus, parainfluenza-, metapneumo-, or coronaviruses were found. Enterovirus was more common in children and was frequently observed in the presence of HHV6B. None of the viruses showed a positive association to the tonsillar disease. Respiratory symptoms were not associated with the prevalence of viruses. This study comprehensively reports a cross-sectional view of intratonsillar virus infections in elective tonsillectomy patients in a wide age range cohort. Tonsils are a major virus reservoir for distinct herpes and respiratory viruses without a positive association with tonsillar disease or respiratory symptoms.

Benign adenoidal hypertrophy caused by adenovirus presenting as a nasopharyngeal mass concerning for malignancy

Benign adenoidal hypertrophy is the most common cause of nasopharyngeal obstruction. However, depending on size and location, masses may cause nasopharyngeal obstruction. We present our experiences with a ten-year-old female who presented with what appeared to be a large nasopharyngeal mass that was initially favored to be malignant and was ultimately found to be adenoid hypertrophy related to acute infection with adenovirus.

Human adenovirus replication and persistence in hypertrophic adenoids and palatine tonsils in children

The role of human adenovirus (HAdV) infection in different acute diseases, such as febrile exudative tonsillitis, conjunctivitis, and pharyngoconjunctival fever is well established. However, the relationships, if any, of HAdV persistence and reactivation in the development of the chronic adenotonsillar disease is not fully understood. The present paper reports a 3-year cross-sectional hospital-based study aimed at detecting and quantifying HAdV DNA and mRNA of the HAdV hexon gene in adenoid and palatine tonsil tissues and nasopharyngeal secretions (NPS) from patients with adenotonsillar hypertrophy or recurrent adenotonsillitis. HAdV C, B, and E were detectable in nearly 50% of the patients, with no association with the severity of airway obstruction, nor with the presence of recurrent tonsillitis, sleep apnea or otitis media with effusion (OME). Despite the higher rates of respiratory viral coinfections in patients with HAdV, the presence of other viruses, including DNA and RNA viruses, had no association with HAdV replication or shedding in secretions. Higher HAdV loads in adenoids showed a significant positive correlation with the presence of sleep apnea and the absence of OME. Although this study indicates that a significant proportion (~85%) of individuals with chronic adenotonsillar diseases have persistent nonproductive HAdV infection, including those by HAdV C, B, and E, epithelial and subepithelial cells in tonsils seem to be critical for HAdV C production and shedding in NPS in some patients, since viral antigen was detected in these regions by immunohistochemistry in four patients, all of which were also positive for HAdV mRNA detection.

Increased anti- EBV VCA IgG antibody levels are associated with need for surgery in patients developing upper respiratory tract complications

INTRODUCTION

The immune reaction developing against Ebstein-Barr virus (EBV) infection may be one of the major determinants of severe adenoid hypertrophy (AH) and chronic otitis media with effusion (COME) needing surgery. In this study, we aimed to investigate the relationship between these antibodies and the need for surgery due to complications such as severe AH and COME.

METHODS

Sixty consecutive patients <15 years old who were admitted to our outpatient clinics between January 2014 and December 2015 with severe AH ± COME and underwent adenoidectomy ± ventilation tube insertion and 129 control patients who had a history of EBV infection at least three months before the inclusion to the study without current symptoms of upper airway obstruction and middle ear disease were included in this study. Two groups of patients and a control group were studied: a) children who underwent adenoidectomy alone with no middle ear disease (group 1), b) children with COME and AH who underwent adenoidectomy and tympanostomy with ventilation tube insertion (group 2), and c) control group without adenoid hypertrophy or otitis media with effusion.

RESULTS

Patients who needed surgery (Group 1 and 2) had significantly higher levels of anti-EBV VCA IgG antibodies than control patients (19.8 ± 16.4 vs. 1.7 ± 0.8 S/CO, p < 0.001). Anti-EBV VCA IgM levels did not differ between groups. Group 2 patients had also higher levels of Anti-EBV VCA IgG antibodies than group 1 patients (35.8 ± 16.7 vs. 11.8 ± 8.5 S/CO, p < 0.001). ROC curve analysis resulted in a cut-off point of 2.92 S/CO level for anti-EBV VCA IgG antibodies for need for surgery in EBV infected patients with 97% sensitivity and 98% specificity.

CONCLUSION

Markedly increased serum anti-EBV VCA IgG antibodies in children who developed upper respiratory tract complications such as severe AH and COME may show the significant role of enhanced immune system reaction in the pathogenesis of these complications due to EBV infection.