Adenoid reservoir for pathogenic biofilm bacteria

Changes in the nasopharyngeal and oropharyngeal microbiota in pediatric obstructive sleep apnea before and after surgery: a prospective study

OBJECTIVE

To explore the changes and potential mechanisms of microbiome in different parts of the upper airway in the development of pediatric OSA and observe the impact of surgical intervention on oral microbiome for pediatric OSA.

METHODS

Before adeno-tonsillectomy, we collected throat swab samples from different parts of the oropharynx and nasopharynx of 30 OSA patients and 10 non-OSA patients and collected throat swab samples from the oropharynx of the above patients one month after the adeno-tonsillectomy. The 16 S rRNA V3-V4 region was sequenced to identify the microbial communities. The correlation analysis was conducted based on clinical characteristics.

RESULTS

There was a significant difference of alpha diversity in different parts of the upper airway of pediatric OSA, but this difference was not found in children with non-OSA. Beta diversity was significantly different between non-OSA and pediatric OSA. At the genus level, the composition of flora in different parts is different between non-OSA and pediatric OSA. The correlation analysis revealed that the relative abundance of Neisseria was significantly correlated with obstructive apnea hypopnea index. Furthermore, the functional prediction revealed that pathways related to cell proliferation and material metabolism were significantly different between non-OSA and pediatric OSA. Besides, the adeno-tonsillectomy has minimal impact on oral microbiota composition in short term.

CONCLUSION

The changes in upper airway microbiome are highly associated with pediatric OSA. The relative abundance of some bacteria was significantly different between OSA and non-OSA. These bacteria have the potential to become new diagnostic and early warning biomarkers.

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.

Pathogenesis of nontypeable Haemophilus influenzae infections in chronic suppurative lung disease

The respiratory tract antimicrobial defense system is a multilayered defense mechanism that relies upon mucociliary clearance and components of both the innate and adaptive immune systems to protect the lungs from inhaled or aspirated microorganisms. One of these potential pathogens, nontypeable Haemophilus influenzae (NTHi), adopts several, multifaceted redundant strategies to successfully colonize the lower airways and establish a persistent infection. NTHi can impair mucociliary clearance, express multiple multifunctional adhesins for various cell types within the respiratory tract and evade host defenses by surviving within and between cells, forming biofilms, increasing antigenic drift, secreting proteases and antioxidants, and by host-pathogen cross-talk, impair macrophage and neutrophil function. NTHi is recognized as an important pathogen in several chronic lower respiratory disorders, such as protracted bacterial bronchitis, bronchiectasis, cystic fibrosis, and primary ciliary dyskinesia. The persistence of NTHi in human airways, including its capacity to form biofilms, results in chronic infection and inflammation, which can ultimately injure airway wall structures. The complex nature of the molecular pathogenetic mechanisms employed by NTHi is incompletely understood but improved understanding of its pathobiology will be important for developing effective therapies and vaccines, especially given the marked genetic heterogeneity of NTHi and its possession of phase-variable genes. Currently, no vaccine candidates are ready for large phase III clinical trials.

[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.

Changes in the oral and nasal microbiota in pediatric obstructive sleep apnea

Background

Several clinical studies have demonstrated that pediatric obstructive sleep apnea (OSA) is associated with dysbiosis of airway mucosal microbiota. However, how oral and nasal microbial diversity, composition, and structure are altered in pediatric OSA has not been systemically explored.

Methods

30 polysomnography-confirmed OSA patients with adenoid hypertrophy, and 30 controls who did not have adenoid hypertrophy, were enrolled. Swabs from four surface oral tissue sites (tongue base, soft palate, both palatine tonsils, and adenoid) and one nasal swab from both anterior nares were collected. The 16S ribosomal RNA (rRNA) V3-V4 region was sequenced to identify the microbial communities.

Results

The beta diversity and microbial profiles were significantly different between pediatric OSA patients and controls at the five upper airway sites. The abundances of Haemophilus, Fusobacterium, and Porphyromonas were higher at adenoid and tonsils sites of pediatric patients with OSA. Functional analysis revealed that the differential pathway between the pediatric OSA patients and controls involved glycerophospholipids and amino acid metabolism.

Conclusions

In this study, the oral and nasal microbiome of pediatric OSA patients exhibited certain differences in composition compared with the controls. However, the microbiota data could be useful as a reference for studies on the upper airway microbiome.

Antibiotic Tolerance Indicative of Persistence Is Pervasive among Clinical Streptococcus pneumoniae Isolates and Shows Strong Condition Dependence

Streptococcus pneumoniae is an important human pathogen, being one of the most common causes of community-acquired pneumonia and otitis media. Antibiotic resistance in S. pneumoniae is an emerging problem, as it depletes our arsenal of effective drugs. In addition, persistence also contributes to the antibiotic crisis in many other pathogens, yet for S. pneumoniae, little is known about antibiotic-tolerant persisters and robust experimental means are lacking. Persister cells are phenotypic variants that exist as a subpopulation within a clonal culture. Being tolerant to lethal antibiotics, they underly the chronic nature of a variety of infections and even help in acquiring genetic resistance. In this study, we set out to identify and characterize persistence in S. pneumoniae. Specifically, we followed different strategies to overcome the self-limiting nature of S. pneumoniae as a confounding factor in the prolonged monitoring of antibiotic survival needed to study persistence. Under optimized conditions, we identified genuine persisters in various growth phases and for four relevant antibiotics through biphasic survival dynamics and heritability assays. Finally, we detected a high variety in antibiotic survival levels across a diverse collection of S. pneumoniae clinical isolates, which assumes that a high natural diversity in persistence is widely present in S. pneumoniae. Collectively, this proof of concept significantly progresses the understanding of the importance of antibiotic persistence in S. pneumoniae infections, which will set the stage for characterizing its relevance to clinical outcomes and advocates for increased attention to the phenotype in both fundamental and clinical research. IMPORTANCE S. pneumoniae is considered a serious threat by the Centers for Disease Control and Prevention because of rising antibiotic resistance. In addition to resistance, bacteria can also survive lethal antibiotic treatment by developing antibiotic tolerance, more specifically, antibiotic tolerance through persistence. This phenotypic variation seems omnipresent among bacterial life, is linked to therapy failure, and acts as a catalyst for resistance development. This study gives the first proof of the presence of persister cells in S. pneumoniae and shows a high variety in persistence levels among diverse strains, suggesting that persistence is a general trait in S. pneumoniae cultures. Our work advocates for higher interest for persistence in S. pneumoniae as a contributing factor for therapy failure and resistance development.

Characteristics of salivary microbiota in children with obstructive sleep apnea: A prospective study with polysomnography

Objectives

The present study aimed to investigate the characteristics of salivary microbiota of children with obstructive sleep apnea (OSA) and to assess longitudinal alterations in salivary microbiota before and after adenotonsillectomy.

Methods

A set of cross-sectional samples consisted of 36 OSA children (17 boys and 19 girls, 7.47 ± 2.24 years old) and 22 controls (9 boys and 13 girls, 7.55 ± 2.48 years old) were included in the study, among which eight OSA children (five boys and three girls, 8.8 ± 2.0 years old) who underwent treatment of adenotonsillectomy were followed up after 1 year. Saliva samples were collected, and microbial profiles were analyzed by bioinformatics analysis based on 16S rRNA sequencing.

Results

In cross-sectional samples, the OSA group had higher α-diversity as estimated by Chao1, Shannon, Simpson, Pielou_e, and observed species as compared with the control group (p < 0.05). β-Diversity based on the Bray–Curtis dissimilarities (p = 0.004) and Jaccard distances (p = 0.001) revealed a significant separation between the OSA group and control group. Nested cross-validated random forest classifier identified the 10 most important genera (Lactobacillus, Escherichia, Bifidobacterium, Capnocytophaga, Bacteroidetes_[G-7], Parvimonas, Bacteroides, Klebsiella, Lautropia, and Prevotella) that could differentiate OSA children from controls with an area under the curve (AUC) of 0.94. Linear discriminant analysis effect size (LEfSe) analysis revealed a significantly higher abundance of genera such as Prevotella (p = 0.027), Actinomyces (p = 0.015), Bifidobacterium (p < 0.001), Escherichia (p < 0.001), and Lactobacillus (p < 0.001) in the OSA group, among which Prevotella was further corroborated in longitudinal samples. Prevotella sp_HMT_396 was found to be significantly enriched in the OSA group (p = 0.02) with significantly higher levels as OSA severity increased (p = 0.014), and it had a lower abundance in the post-treatment group (p = 0.003) with a decline in each OSA child 1 year after adenotonsillectomy.

Conclusions

A significantly higher microbial diversity and a significant difference in microbial composition and abundance were identified in salivary microbiota of OSA children compared with controls. Meanwhile, some characteristic genera (Prevotella, Actinomyces, Lactobacillus, Escherichia, and Bifidobacterium) were found in OSA children, among which the relationship between Prevotella spp. and OSA is worth further studies.

Immortelle (Helichrysum italicum (Roth) G. Don) Essential Oil Showed Antibacterial and Biofilm Inhibitory Activity against Respiratory Tract Pathogens

The biofilm formation of bacteria in different parts of the human body can influence the success of antibiotic therapy. Essential oils (EOs) and their components are becoming increasingly popular in point of view of medicinal applications, because of their antibacterial efficacy. The immortelle EO has been used traditionally as an expectorant; however, there are no studies summarizing its antibacterial effect against respiratory tract bacteria. Our aim was to investigate the antibacterial and biofilm inhibitory activity of immortelle (Helichrysum italicum) EO against respiratory tract pathogens such as Haemophilus influenzae, H. parainfluenzae, Pseudomonas aeruginosa and Streptococcus pneumoniae. In order to prove the antibacterial effect of the immortelle EO, broth microdilution and biofilm inhibition tests, and membrane damage assay were investigated. Scanning electron microscopy was used to identify the structural modifications in bacterial cells. Our results showed that immortelle EO has antibacterial and anti-biofilm effects against respiratory tract bacteria used in this study. H. parainfluenzae was the most sensitive to each treatment, however, P. aeruginosa was the most resistant bacteria. In conclusion, the studied EO may have a role in the treatment of respiratory tract infections due to their antibacterial and anti-biofilm activity.

Biofilm aggregates and the host airway-microbial interface

Biofilms are multicellular microbial aggregates that can be associated with host mucosal epithelia in the airway, gut, and genitourinary tract. The host environment plays a critical role in the establishment of these microbial communities in both health and disease. These host mucosal microenvironments however are distinct histologically, functionally, and regarding nutrient availability. This review discusses the specific mucosal epithelial microenvironments lining the airway, focusing on: i) biofilms in the human respiratory tract and the unique airway microenvironments that make it exquisitely suited to defend against infection, and ii) how airway pathophysiology and dysfunctional barrier/clearance mechanisms due to genetic mutations, damage, and inflammation contribute to biofilm infections. The host cellular responses to infection that contribute to resolution or exacerbation, and insights about evaluating and therapeutically targeting airway-associated biofilm infections are briefly discussed. Since so many studies have focused on Pseudomonas aeruginosa in the context of cystic fibrosis (CF) or on Haemophilus influenzae in the context of upper and lower respiratory diseases, these bacteria are used as examples. However, there are notable differences in diseased airway microenvironments and the unique pathophysiology specific to the bacterial pathogens themselves.

Recurrent Acute Otitis Media Environmental Risk Factors: A Literature Review from the Microbiota Point of View

Acute otitis media (AOM) constitutes a multifactorial disease, as several host and environmental factors contribute to its occurrence. Prevention of AOM represents one of the most important goals in pediatrics, both in developing countries, in which complications, mortality, and deafness remain possible consequences of the disease, compared to in developed countries, in which this condition has an important burden in terms of medical, social, and economical implications. The strategies for AOM prevention are based on reducing the burden of risk factors, through the application of behavioral, environmental, and therapeutic interventions. The introduction of culture-independent techniques has allowed high-throughput investigation of entire bacterial communities, providing novel insights into the pathogenesis of middle ear diseases through the identification of potential protective bacteria. The upper respiratory tract (URT) is a pivotal region in AOM pathogenesis, as it could act as a source of pathogens than of protective microorganisms for the middle ear (ME). Due to its direct connection with the external ambient, the URT is particularly exposed to the influence of environmental agents. The aim of this review was to evaluate AOM environmental risk factors and their impact on URT microbial communities, and to investigate AOM pathogenesis from the microbiota perspective.

Mucosal immune cell populations and the bacteriome of adenoids and tonsils from people living with HIV on suppressive antiretroviral therapy

Ear, nose, and throat (ENT) conditions are prevalent in people living with HIV (PLWH) and occur at all strata of CD4 counts and despite antiretroviral therapy (ART). ENT conditions are underreported in PLWH. Also, little is known about the adenotonsillar microbiota and its relation to resident adaptive and innate immune cells. To bridge this gap, we characterized immune cell populations and the bacterial microbiota of two anatomical sites (adenoids, tonsils) and the oral cavity. Adenoids and tonsils were obtained from PLWH (n = 23) and HIV-seronegative individuals (SN, n = 16) after nasal surgery and tonsillectomy and processed for flow cytometry. Nasopharyngeal, oropharyngeal swabs, and oral rinses were collected prior to surgery for 16S sequencing. Wilcoxon rank sum test, principal coordinate analysis, permutational multivariate analysis of variance, and linear discriminant analysis (LEfSe) were used to assess differences between PLWH and SN. Spearman’s correlations were performed to explore interactions between the bacteriome and mucosal immune cells. Of the 39 individuals included, 30 (77%) were men; the median age was 32 years. All PLWH were on ART, with a median CD4 of 723 cells. ENT conditions were classified as inflammatory or obstructive, with no differences observed between PLWH and SN. PLWH had higher frequencies of activated CD4+ and CD8+ T cells, increased T helper (Th)1 and decreased Th2 cells; no differences were observed for B cells and innate immune cells. Alpha diversity was comparable between PLWH and SN at all 3 anatomical sites (adenoids, tonsils, and oral cavity). The impact of HIV infection on the bacterial community structure at each site, as determined by Permutational multivariate analysis of variance, was minor and not significant. Two discriminant genera were identified in adenoids using LEfSe: Staphylococcus for PLWH and Corynebacterium for SN. No discriminant genera were identified in the oropharynx and oral cavity. Niche-specific differences in microbial diversity and communities were observed. PLWH shared less of a core microbiota than SN. In the oropharynx, correlation analysis revealed that Th17 cells were inversely correlated with bacterial richness and diversity, Filifactor, Actinomyces and Treponema; and positively correlated with Streptococcus. Our study contributes toward understanding the role of the adenotonsillar microbiota in the pathophysiology of ENT conditions.

Fluorescence in situ hybridisation in Carnoy's fixed tonsil tissue

Fluorescence in situ hybridisation (FISH) is a powerful molecular technique that enables direct visualisation of specific bacterial species. Few studies have established FISH protocols for tonsil tissue in Carnoy’s fixative, accordingly limiting its application to investigate the pathogenesis of tonsillar hyperplasia. Tonsil tissue from 24 children undergoing tonsillectomy for either recurrent tonsillitis or sleep-disordered breathing were obtained during a previous study. The specificity of each of the five FISH probes (Fusobacterium spp., Bacteroides spp., Streptococcus spp., Haemophilus influenzae and Pseudomonas spp.) were successfully optimised using pure and mixed bacterial isolates, and in Carnoy’s fixed tonsil tissue. Bacteroides spp. were present in 100% of patients with microcolonies. In comparison, the prevalence of Fusobacterium spp. was 93.8%, Streptococcus spp. 85.7%, H. influenzae 82.35% and Pseudomonas spp. 76.5%. Notable differences in the organisation of bacterial taxa within a single microcolony were also observed. This is the first study to establish a robust FISH protocol identifying multiple aerobic and anaerobic bacteria in Carnoy’s fixed tonsil tissue. This protocol provides a strong foundation for combining histological and microbiological analyses of Carnoy’s fixed tonsil samples. It may also have important implications on the analysis of microorganisms in other human tissues prepared using the same techniques.

Bacterial Identification and Visualization of Bacterial Biofilms Adjacent to Fracture Sites After Internal Fixation

Objectives: The primary aims of this study were to determine if any correlation exists in cases of fracture fixation among: (1) bacterial profiles recovered from the instrumentation and adjacent tissues; (2) the type of orthopedic injury; and (3) the clinical outcome-union versus nonunion. A secondary goal was to compare culture and molecular diagnostics for identifying the bacterial species present following fracture fixation. Design: Single-institution, prospective case-control cohort study. Setting: Single level 1 trauma center. Patients: Forty-nine bony nonunion cases undergoing revision internal fixation and 45 healed fracture controls undergoing removal of hardware. Intervention: Bacterial infection was detected by standard microbial culture methods and by a pan-eubacterial domain, molecular diagnostic (MDx) assay. Confirmation of culture and MDx results was achieved with bacterial ribosomal 16S rRNA fluorescence in situ hybridization (FISH) to visualize bacterial biofilms. Main Outcome Measurements: MDx and microbial culture methods results were the primary study outcomes. Results: Ninety-four percent of the nonunion cohort and 93% of the union cohort had bacteria detected by the MDx. Seventy-eight percent of the nonunion cases and 69% of the controls were culture negative, but MDx positive. Although no significant differences in bacterial composition were observed between the cases and controls, differences were observed when cases were divided by comorbidities. Conclusion: The MDx is more sensitive than microbial culture in detecting bacterial presence. The lack of significantly different findings with regard to bacterial profile identified between the cases and controls suggests that host factors and environmental conditions are largely responsible for determining if bony union will occur. Level of Evidence: Diagnostic Level III. See Instructions for Authors for a complete description of levels of evidence.

Access to highly specialized growth substrates and production of epithelial immunomodulatory metabolites determine survival of Haemophilus influenzae in human airway epithelial cells

Haemophilus influenzae (Hi) infections are associated with recurring acute exacerbations of chronic respiratory diseases in children and adults including otitis media, pneumonia, chronic obstructive pulmonary disease and asthma. Here, we show that persistence and recurrence of Hi infections are closely linked to Hi metabolic properties, where preferred growth substrates are aligned to the metabolome of human airway epithelial surfaces and include lactate, pentoses, and nucleosides, but not glucose that is typically used for studies of Hi growth in vitro. Enzymatic and physiological investigations revealed that utilization of lactate, the preferred Hi carbon source, required the LldD L-lactate dehydrogenase (conservation: 98.8% of strains), but not the two redox-balancing D-lactate dehydrogenases Dld and LdhA. Utilization of preferred substrates was directly linked to Hi infection and persistence. When unable to utilize L-lactate or forced to rely on salvaged guanine, Hi showed reduced extra- and intra-cellular persistence in a murine model of lung infection and in primary normal human nasal epithelia, with up to 3000-fold attenuation observed in competitive infections. In contrast, D-lactate dehydrogenase mutants only showed a very slight reduction compared to the wild-type strain. Interestingly, acetate, the major Hi metabolic end-product, had anti-inflammatory effects on cultured human tissue cells in the presence of live but not heat-killed Hi, suggesting that metabolic endproducts also influence HI-host interactions. Our work provides significant new insights into the critical role of metabolism for Hi persistence in contact with host cells and reveals for the first time the immunomodulatory potential of Hi metabolites.

Assessment of sleep-disordered breathing in pediatric otitis media with effusion

BACKGROUND

Given the role of adenoid in the pathogenesis of otitis media with effusion (OME) and sleep-disordered breathing (SDB), the present study aimed to investigate the sleep quality and the impact of adenoidectomy on improvement of sleep symptoms in children with OME.

METHODS

Children with SDB or OME, aged 3-12 years, were prospectively enrolled before undergoing adenoidectomy in a tertiary medical center. The symptom severity of obstructive sleep apnea syndrome (OSAS) was evaluated by OSA-18 questionnaire on the day before and 6 months after surgery.

RESULTS

In total, 79 pediatric patients including 50 children with SDB and 29 children with OME were enrolled. The mean total OSA-18 score was 56.5 ± 15.1 and ten (34.5%) children experienced moderate to severe symptoms of OSAS as indicated by OSA-18 score ≥ 60 in OME group. After surgery, patients in both SDB and OME groups experienced improvement (both p < 0.001) and presented no difference in the scores of OSA-18. The proportional change in OSA-18 scores after surgery was related to pre-operative OSA-18 scores and BMI in OME patients (r_s = 0.400 and 0.542, p = 0.047 and 0.008), and to pre-operative OSA-18 scores in patients with SDB (r_s = 0.393, p = 0.008).

CONCLUSION

Children with OME experienced significant symptoms of OSAS and associated impairment of quality of life. Adenoidectomy is effective in the improvement of sleep symptoms in these patients. Comprehensive assessment of sleep breathing as planning surgery for OME children is suggested.

Bacterial DNA screening to characterize surgical site infection risk in orthopaedic patients

Purpose

To provide an initial characterization of relevant bacterial DNA profiles for patients undergoing closed-fracture fixation or total joint arthroplasties.

Patients and methods

Swabs were collected and analyzed using Polymerase Chain Reaction from adult patients undergoing closed-fracture fixation or total shoulder, knee, or hip arthroplasties.

Results

Bacterial DNA profiles varied across the different orthopaedic patient populations, and produced uncharacteristic profile shifts with direct relevance to each clinical infection.

Conclusion

Findings provide a foundational dataset regarding bacterial colonization of relevant anatomic sites that can act as sources of surgical site infections for patients.

Dysregulation of immune response in otitis media

Objective

Otitis media (OM) is a common reason for children to be prescribed antibiotics and undergo surgery but a thorough understanding of disease mechanisms is lacking. We evaluate the evidence of a dysregulated immune response in the pathogenesis of OM.

Methods

A comprehensive systematic review of the literature using search terms [otitis media OR glue ear OR AOM OR OME] OR [middle ear AND (infection OR inflammation)] which were run through Medline and Embase via Ovid, including both human and animal studies. In total, 82 955 studies underwent automated filtering followed by manual screening. One hundred studies were included in the review.

Results

Most studies were based on in vitro or animal work. Abnormalities in pathogen detection pathways, such as Toll-like receptors, have confirmed roles in OM. The aetiology of OM, its chronic subgroups (chronic OM, persistent OM with effusion) and recurrent acute OM is complex; however, inflammatory signalling mechanisms are frequently implicated. Host epithelium likely plays a crucial role, but the characterisation of human middle ear tissue lags behind that of other anatomical subsites.

Conclusions

Translational research for OM presently falls far behind its clinical importance. This has likely hindered the development of new diagnostic and treatment modalities. Further work is urgently required; particularly to disentangle the respective immune pathologies in the clinically observed phenotypes and thereby work towards more personalised treatments.

Characteristics of the bacterial microbiota in the upper respiratory tract of children

PURPOSE

The respiratory tract microbiota are deemed as the gatekeeper to health. Consequently, microbiota dysbiosis can lead to the development of diseases. To identify the exact origins of the localized pathogenic bacteria, we investigated bacterial composition in the upper airway tract.

METHODS

Separate mucosal swabs were collected from nostril or oropharynx of each participant. Meanwhile, the lymphoid tissues including adenoids and tonsils were collected during operation. DNAs were exacted from all the samples for the following 16S rRNA analysis.

RESULTS

At the phylum level, the basic bacterial structures in the adenoids, tonsils, oropharynx, and nostrils were generally similar: five main phyla Firmicutes, Proteobacteria, Bacteroidetes, Actinobacteria, and Fusobacteria form the majority of the microbiota. However, across these four sites, the microbiota composition differed. More specifically, the bacterial composition in the nostrils was unique. There, Firmicutes and Actinobacteria were the most abundant phyla, while Bacteroides and Fusobacteria were the least abundant. At the genus level, Staphylococcus, Dolosigranulum, Corynebacterium, and Moraxella were the most plentiful, while Fusobacteria was the least ample. Across all sites, Streptococcus displayed similar abundances. Fusobacteria exhibited higher abundances in the lymphoid tissues and oropharynx. Haemophilus and Neisseria were more plentiful in the tonsils and oropharynx. Notably, Klebsiella, which is normally localized to the gut, was abundant in the adenoids and tonsils.

CONCLUSION

Our data indicate that promising pathogenic bacteria originate from all sites in the upper airway. The upper tract lymphoid tissues, normally considered as immune organs, may also serve as reservoirs for pathogenic bacteria.

Detection of respiratory viruses in primary cholesteatoma tissues

Cholesteatomas are frequent middle ear benign tumors of unknown etiology. Infectious agents have been considered as possible contributing factors in the pathogenesis of cholesteatomas. Aiming to investigate the presence of respiratory viruses in primary cholesteatoma tissues, 26 formalin-fixed paraffin-embedded primary cholesteatoma tissues obtained from patients seen at the of the Clinical Hospital of the University of São Paulo School of Medicine, in Ribeirão Preto, Brazil were tested by real-time polymerase chain reaction (PCR). Considering the PCR results, 35% of the tissues were positive for human rhinovirus (HRV), 15.3% for human enterovirus (EV), 3.8% for human metapneumovirus (HMPV), and 3.8% for human bocavirus (HBoV). Serial immunohistochemistry for virus antigens and cell surface markers evidenced that the viruses were associated with fibroblasts, dendritic cells, macrophages, B lymphocytes, CD4⁺ , and CD8⁺ T lymphocytes. These findings indicate for the first time the presence of active respiratory virus infection in primary cholesteatoma tissues, suggesting that persisting virus infection in the middle could play a role in the pathogenesis and evolution of cholesteatomas.

Tissue microbiota in nasopharyngeal adenoid and its association with pneumococcal carriage

The microbial colonization in the nasopharynx is a prerequisite for the onset of infectious diseases. For successful infection, pathogens should overcome host defenses as well as compete effectively with the resident microbiota. Hence, elucidating the richness and diversity of the microbiome at the site of pathogen colonization is pivotal. Here, we investigated the adenoidal tissue microbiota collected through adenoidectomy to evaluate the impact of Streptococcus pneumoniae. Prospectively, children with sleep-disordered breathing (SDB) and otitis media with effusion (OME) were enrolled. During adenoidectomy, the nasopharyngeal swab and adenoid tissues were collected to determine the pneumococcal carriage and tissue microbiota, using multiplex PCR and 16S ribosomal RNA (16S rRNA) pyrosequencing. A total of 66 pediatric patients comprising 38 children with SDB and 28 children with OME were enrolled. There was no difference between the bacterial cultures from the surface of the nasopharyngeal adenoid in the SDB and OME groups. Thirty-four samples (17 SDB and 17 OME) underwent 16S rRNA pyrosequencing and fulfilled the criteria for further analysis. The Shannon diversity index for the samples from the SDB patients was found to be higher than that observed for the samples from OME patients, although the difference was not significant (p = 0.095). The Shannon diversity index for the samples negative for the pneumococcal carriage was significantly higher than that for the samples positive for pneumococcal carriage (p = 0.038). Alloprevotella, Staphylococcus, Moraxella, and Neisseriaceae were significantly dominant in the samples positive for the pneumococcal carriage. Dialister was significantly less present in the adenoid tissue positive for the pneumococcal carriage. Streptococcus pneumoniae, one of the most common pathogens of the airway, significantly influences the composition and diversity of the microbiota in the nasopharyngeal adenoid. Thus, bacterial community analysis based on 16S rRNA pyrosequencing allows for better understanding of the relationship between the adenoidal microbial communities.

Beyond the pan-genome: current perspectives on the functional and practical outcomes of the distributed genome hypothesis

The principle of monoclonality with regard to bacterial infections was considered immutable prior to 30 years ago. This view, espoused by Koch for acute infections, has proven inadequate regarding chronic infections as persistence requires multiple forms of heterogeneity among the bacterial population. This understanding of bacterial plurality emerged from a synthesis of what-were-then novel technologies in molecular biology and imaging science. These technologies demonstrated that bacteria have complex life cycles, polymicrobial ecologies, and evolve in situ via the horizontal exchange of genic characters. Thus, there is an ongoing generation of diversity during infection that results in far more highly complex microbial communities than previously envisioned. This perspective is based on the fundamental tenet that the bacteria within an infecting population display genotypic diversity, including gene possession differences, which result from horizontal gene transfer mechanisms including transformation, conjugation, and transduction. This understanding is embodied in the concepts of the supragenome/pan-genome and the distributed genome hypothesis (DGH). These paradigms have fostered multiple researches in diverse areas of bacterial ecology including host-bacterial interactions covering the gamut of symbiotic relationships including mutualism, commensalism, and parasitism. With regard to the human host, within each of these symbiotic relationships all bacterial species possess attributes that contribute to colonization and persistence; those species/strains that are pathogenic also encode traits for invasion and metastases. Herein we provide an update on our understanding of bacterial plurality and discuss potential applications in diagnostics, therapeutics, and vaccinology based on perspectives provided by the DGH with regard to the evolution of pathogenicity.

Assessment of Friedman Classification by Measuring Actual Tonsil Size During Surgery

Background and Objectives: Adenotonsillar enlargement is a common cause of pediatric illnesses, including obstructive respiratory disease and recurrent airway infection. The current tonsil grading systems evaluate tonsil size, but the correlation with actual tonsillar size in a clinical setting has not been established.Materials and Method: Between May and July of 2018, we recruited 31 children who underwent adenotonsillectomy with no major craniofacial abnormalities. The actual size of the palatine tonsils, the long (L1) and short (S1) axes of the tonsil beyond the anterior pillar, and the real axes (L2 and S2) after tonsil extraction from the fossa were measured during surgery. Adenoid size was determined by measuring the adenoid-nasopharynx (AN) ratio through lateral view x-ray of the neck.Results: Though S1 was related to the Friedman scale (p<0.001), measured real axes were not (L2: p=0.058, S2: p=0.056). Also, adenoid size and AN ratio did not relate statistically to the Friedman scale (p=0.565). One of the measured real tonsil size parameters (S2) was related to AN ratio (p=0.048).Conclusion: For pediatric patients undergoing tonsillectomy and adenoidectomy, the Friedman grading scale based on physical examination may not reflect the actual size of the tonsils. Therefore, for children with obstructive sleep disorder or recurrent tonsillitis, intraoperative measurement of tonsil size can be helpful.

Antibacterial activity of a DNA topoisomerase I inhibitor versus fluoroquinolones in Streptococcus pneumoniae

The DNA topoisomerase complement of Streptococcus pneumoniae is constituted by two type II enzymes (topoisomerase IV and gyrase), and a single type I enzyme (topoisomerase I). These enzymes maintain the DNA topology, which is essential for replication and transcription. While fluoroquinolones target the type II enzymes, seconeolitsine, a new antimicrobial agent, targets topoisomerase I. We compared for the first time the in vitro effect of inhibition of topoisomerase I by seconeolitsine and of the type II topoisomerases by the fluoroquinolones levofloxacin and moxifloxacin. We used three isogenic non-encapsulated strains and five non-vaccine serotypes isolates belonging to two circulating pneumococcal clones, ST63⁸ (2 strains) and ST156^9V (3 strains). Each group contained strains with diverse susceptibility to fluoroquinolones. Minimal inhibitory concentrations, killing curves and postantibiotic effects were determined. Seconeolitsine demonstrated the fastest and highest bactericidal activity against planktonic bacteria and biofilms. When fluoroquinolone-susceptible planktonic bacteria were considered, seconeolitsine induced postantibiotic effects (1.00−1.87 h) similar than levofloxacin (1.00−2.22 h), but longer than moxifloxacin (0.39−1.71 h). The same effect was observed in sessile bacteria forming biofilms. Seconeolitsine induced postantibiotic effects (0.84−2.31 h) that were similar to those of levofloxacin (0.99−3.32 h) but longer than those of moxifloxacin (0.89−1.91 h). The greatest effect was observed in the viability and adherence of bacteria in the postantibiotic phase. Seconeolitsine greatly reduced the thickness of the biofilms formed in comparison with fluoroquinolones: 2.91 ± 0.43 μm (seconeolitsine), 7.18 ± 0.58 μm (levofloxacin), 17.08 ± 1.02 μm (moxifloxacin). When fluoroquinolone-resistant bacteria were considered, postantibiotic effects induced by levofloxacin and moxifloxacin, but not by seconeolitsine, were shorter, decreasing up to 5-fold (levofloxacin) or 2-fold (moxifloxacin) in planktonic cells, and up to 1.7 (levofloxacin) or 1.4-fold (moxifloxacin) during biofilm formation. Therefore, topoisomerase I inhibitors could be an alternative for the treatment of pneumococcal diseases, including those caused by fluoroquinolone-resistant isolates.

The effects of radiofrequency on the bacteriological and histological characteristics of tonsils in patients with chronic and persistent tonsillitis

OBJECTIVES

Tonsillotomy with radiofrequency (RF) is one of the newest treatments for chronic tonsillitis, but the mechanism of RF effects and complications are still pending. The aim of this study was to evaluate the effects of RF on the histological and bacteriological characteristics of the tonsils (Case-control study).

MATERIALS AND METHODS

In fifty-two patients with chronic tonsillitis in 2017-2018, immediately after tonsillectomy, the tonsils were divided into 2sections; one sample treated with RF, and the other one considered as control, without intervention. All tonsil samples sent for histological and bacteriological study: morphometric assays made by Digitizer software, and type of bacterial colonies identified by microbiological and biochemical tests. Willcoxon and McNemar tests were used for statistical analysis and level of significance was p ≤ .05.

RESULTS

Tonsil mucosal thickness (2202.98 ± 323.09 vs. 2463.94 ± 357.61 μm) and size of the tonsil nodule (28,000.42 ± 9608.75 vs. 36,692.81 ± 7040.74 μm²) were significantly lower in the RF+ group than other group (p = .001 and p = .01, respectively). There was no significant differences in thickness of the tonsil epithelium (p = .075), number of lymphoid nodules (p = .860), and the number of reticular tonsil epithelium (p = .813) between the two groups. Bacterial growth in RF- and RF+ groups had no statistically significant difference (p = .06), however, the average colony count of S. aureus in RF+ tonsils were significantly lower, and total number of bacterial colonies were significantly lower in RF+ group(1405 ± 156 vs. 2471 ± 156), (p = .001).

CONCLUSION

RF surgery has significant effects on size of the nodules, thickness of the mucous layer and bacteriological characteristics of tonsil tissue. Especially S. aureus seems to be more sensitive to RF effects.

Upper Respiratory Tract Microbiome and Otitis Media Intertalk: Lessons from the Literature

Otitis media (OM) is one of the most common diseases occurring during childhood. Microbiological investigations concerning this topic have been primarily focused on the four classical otopathogens (Streptococcus pneumoniae, Haemophilus influenzae, Moraxella catarrhalis and Streptococcus pyogenes) mainly because most of the studies have been conducted with culture-dependent methods. In recent years, the introduction of culture-independent techniques has allowed high-throughput investigation of entire bacterial communities, leading to a better comprehension of the role of resident flora in health and disease. The upper respiratory tract (URT) is a region of major interest in otitis media pathogenesis, as it could serve as a source of pathogens for the middle ear (ME). Studies conducted with culture-independent methods in the URT and ME have provided novel insights on the pathogenesis of middle ear diseases through the identification of both possible new causative agents and of potential protective bacteria, showing that imbalances in bacterial communities could influence the natural history of otitis media in children. The aim of this review is to examine available evidence in microbiome research and otitis media in the pediatric age, with a focus on its different phenotypes: acute otitis media, otitis media with effusion and chronic suppurative otitis media.

Antimicrobial Photodynamic Therapy with Chlorin e6 Is Bactericidal against Biofilms of the Primary Human Otopathogens

Otitis media (OM), or middle ear disease, is the most prevalent bacterial infection in children and the primary reason for antibiotic use and surgical intervention in the pediatric population. Biofilm formation by the major bacterial otopathogens, Moraxella catarrhalis, Streptococcus pneumoniae, and nontypeable Haemophilus influenzae, has been shown to occur within the middle ears of OM patients and is a key factor in the development of recurrent disease, which may result in hearing impairment and developmental delays. Bacterial biofilms are inherently impervious to most antibiotics and present a significant challenge to the immune system. In this study, we demonstrate that antimicrobial photodynamic therapy (aPDT) using the photosensitizer chlorin e6 elicits significant bactericidal activity versus planktonic and biofilm-associated otopathogens and supports further analyses of this novel, efficacious, and promising technology as an adjunctive treatment for acute and recurrent OM.

Moraxella catarrhalis, Streptococcus pneumoniae, and nontypeable Haemophilus influenzae (NTHi) are ubiquitous upper respiratory opportunistic pathogens. Together, these three microbes are the most common causative bacterial agents of pediatric otitis media (OM) and have therefore been characterized as the primary human otopathogens. OM is the most prevalent bacterial infection in children and the primary reason for antibiotic administration in this population. Moreover, biofilm formation has been confirmed as a primary mechanism of chronic and recurrent OM disease. As bacterial biofilms are inherently metabolically recalcitrant to most antibiotics and these complex structures also present a significant challenge to the immune system, there is a clear need to identify novel antimicrobial approaches to treat OM infections. In this study, we evaluated the potential efficacy of antibacterial photodynamic therapy (aPDT) with the photosensitizer chlorin e6 (Ce6) against planktonic as well as biofilm-associated M. catarrhalis, S. pneumoniae, and NTHi. Our data indicate aPDT with Ce6 elicits significant bactericidal activity against both planktonic cultures and established biofilms formed by the three major otopathogens (with an efficacy of ≥99.9% loss of viability). Notably, the implementation of a novel, dual-treatment aPDT protocol resulted in this disinfectant effect on biofilm-associated bacteria and, importantly, inhibited bacterial regrowth 24 h posttreatment. Taken together, these data suggest this novel Ce6-aPDT treatment may be a powerful and innovative therapeutic strategy to effectively treat and eradicate bacterial OM infections and, significantly, prevent the development of recurrent disease.

IMPORTANCE Otitis media (OM), or middle ear disease, is the most prevalent bacterial infection in children and the primary reason for antibiotic use and surgical intervention in the pediatric population. Biofilm formation by the major bacterial otopathogens, Moraxella catarrhalis, Streptococcus pneumoniae, and nontypeable Haemophilus influenzae, has been shown to occur within the middle ears of OM patients and is a key factor in the development of recurrent disease, which may result in hearing impairment and developmental delays. Bacterial biofilms are inherently impervious to most antibiotics and present a significant challenge to the immune system. In this study, we demonstrate that antimicrobial photodynamic therapy (aPDT) using the photosensitizer chlorin e6 elicits significant bactericidal activity versus planktonic and biofilm-associated otopathogens and supports further analyses of this novel, efficacious, and promising technology as an adjunctive treatment for acute and recurrent OM.

Vascular endothelial growth factor and transforming growth factor β in hypertrophic adenoids in children suffering from otitis media with effusion

OBJECTIVES

The study objective was to assess the levels of VEGF-A and TGF-β cytokines in the children with adenoid hypertrophy concomitant with exudative otitis media (OME) and in children with adenoid hypertrophy (HA) alone.

METHODS

The study material consisted of hypertrophic adenoids removed during adenoidectomy from 39 children (20 girls and 19 boys), aged 2-7 years suffering from OME. The reference group included 41 children (19 girls and 22 boys), aged from 3 to 9 years with adenoid hypertrophy. The levels of VEGF-A and TGF-β were determined in supernatants obtained from phytohemagglutinin-stimulated cell cultures of the adenoids using a commercial enzyme-linked immunosorbent assay kit.

RESULTS

The median VEGF-A and mean TGF-β concentrations in the study group were significantly higher than those in the reference group (503 pg/mL versus 201 pg/mL, P < 0.001 and 224 pg/mL versus 132 pg/mL, P < 0.001, respectively). ROC analysis revealed that the area under the curve (AUC) for VEGF-A was 0.952 with diagnostic sensitivity and specificity of 95%, whereas for TGF-β it was 0.902 with 60% sensitivity and the same specificity as for VEGF-A. There was no significant difference between the AUC for VEGF-A and TGF-β (P = 0.573).

CONCLUSIONS

The changes in the levels of VEGF-A and TGF-β may indicate bacterial pathogen as one of the causes of exudative otitis media in children. Determination of VEGF-A and TGF-β could be used as additional and objective tests to confirm the clinical diagnosis.

Bacterial biofilm in adenoids of children with chronic otitis media. Part II: a case-control study of nasopharyngeal microbiota, virulence, and resistance of biofilms in adenoids

Background: We previously described that adenoid tissue in children with chronic otitis media (COM) contained more mucosal biofilms than adenoid tissue removed for hypertrophy.Aims/objectives: The aim of the second part was to characterize nasopharyngeal microbiota and explore virulence of the most common middle ear pathogens.Material and methods: Bacteriological analysis was performed following a culture-based approach on the samples recovered from 30 patients of COM group (15 biofilm-positive and 15 biofilm-negative) and from 30 patients of a control group (15 biofilm-positive and 15 biofilm-negative). Virulence factors of Streptococcus pneumoniae, Streptococcus pyogenes, and Haemophilus influenzae were investigated.Results: The most frequent species were Firmicutes followed by Proteobacteria and Actinobacteria. The presence of biofilm was statistically associated with an increase of the number of bacterial species and Firmicutes phylum regardless of the condition (case/control). No virulence factors associated with invasive isolates were found for the most common middle ear pathogens.Conclusions and significance: This case-control study demonstrated that the presence of COM plus biofilm was associated with a given microbiota which contained more Firmicutes. Our study allows a better understanding of physiopathological mechanisms involved in chronic otitis media and paves the way for further investigations.

Bacterial Biofilm and its Role in the Pathogenesis of Disease

Recognition of the fact that bacterial biofilm may play a role in the pathogenesis of disease has led to an increased focus on identifying diseases that may be biofilm-related. Biofilm infections are typically chronic in nature, as biofilm-residing bacteria can be resilient to both the immune system, antibiotics, and other treatments. This is a comprehensive review describing biofilm diseases in the auditory, the cardiovascular, the digestive, the integumentary, the reproductive, the respiratory, and the urinary system. In most cases reviewed, the biofilms were identified through various imaging technics, in addition to other study approaches. The current knowledge on how biofilm may contribute to the pathogenesis of disease indicates a number of different mechanisms. This spans from biofilm being a mere reservoir of pathogenic bacteria, to playing a more active role, e.g., by contributing to inflammation. Observations also indicate that biofilm does not exclusively occur extracellularly, but may also be formed inside living cells. Furthermore, the presence of biofilm may contribute to development of cancer. In conclusion, this review shows that biofilm is part of many, probably most chronic infections. This is important knowledge for development of effective treatment strategies for such infections.

Differential IL-17A response to S. pneumoniae in adenoid tissue of children with sleep disordered breathing and otitis media with effusion

Streptococcus pneumonia, one of the major colonizers in nasopharyngeal adenoids, has been the predominant pathogen causing acute otitis media (AOM) in children. Recent evidence suggests an association between IL-17A-mediated immune response and the clearance of pneumococcal colonization in nasopharyngeal adenoids. Here, we evaluated the expressions of IL-17A and associated genes in hypertrophic adenoid tissues of children with sleep-disordered breathing (SDB) and otitis media with effusion (OME) and their association with pneumococcal carriage. Sixty-six pediatric patients with adenoid hypertrophy were enrolled. During adenoidectomy, nasopharyngeal swab and adenoid tissues were used to determine pneumococcal carriage and IL-17A expression. Our results revealed significantly higher levels of IL-17A and IL-17A:IL-10 mRNA in the SDB patients positive for nasopharyngeal pneumococcal carriage than those negative. However, these differences were not significant in the OME group. These results suggested, in OME patients, prolonged or chronic pneumococcal carriage may occur because of insufficient IL-17A-mediated mucosal clearance, and could further lead to AOM and OME development.

The bacteriome of otitis media with effusion: Does it originate from the adenoid?

OBJECTIVE

The aim of this study was to evaluate the composition and the diversity of bacteriome in middle ear effusion (MEE) and adenoid specimens of pediatric patients having otitis media with effusion (OME).

MATERIALS AND METHODS

Sample collection from children with OME followed by next generation sequencing. Seventeen adenoid and 43 middle ear effusion specimens from 25 children having OME were evaluated. Microbiome analysis was performed via Ion 16S rRNA metagenomics kit.

RESULTS

Twenty-two different bacterial species were identified from all of the samples analyzed. There were variations in the prevalence and relative abundance of the bacteriome observed between adenoid and MEE samples. MEE microbiome was significantly dominated by Alloicoccus otitis (44%), Turicella otitidis (6%), and Staphylococcus auricularis (3%). Whereas, Rothia mucilaginosa (39%), R. dentocariosa (11%), S. aureus (5%), Veillonella rogosae (2%), Granulicatella elegans (2%), Granulicatella adiacens (2%), Eikenella corrodens (1%), and Prevotella nanceiensis (1%) had significantly higher relative abundance in adenoid samples. Overall, there was no statistically significant difference in alpha diversity of MEE and adenoid samples, whereas adenoid samples constituted a cluster in the beta diversity graph.

CONCLUSION

Bacteriome of MEE is mostly dominated by A. otitis yet accompanied by other bacteria with lower relative abundances suggests that OME is likely to be a polymicrobial process. Despite similarities, significant differences in relative abundances of several predominant species between bacteriome in the MEE and adenoid put the theory that OME in children is originated from the adenoids under question.

Role of Biofilms in Children with Chronic Adenoiditis and Middle Ear Disease

Chronic adenoiditis occurs frequently in children, and it is complicated by the subsequent development of recurrent or chronic middle ear diseases, such as recurrent acute otitis media, persistent otitis media with effusion and chronic otitis media, which may predispose a child to long-term functional sequalae and auditory impairment. Children with chronic adenoidal disease who fail to respond to traditional antibiotic therapy are usually candidates for surgery under general anaesthesia. It has been suggested that the ineffectiveness of antibiotic therapy in children with chronic adenoiditis is partially related to nasopharyngeal bacterial biofilms, which play a role in the development of chronic nasopharyngeal inflammation due to chronic adenoiditis, which is possibly associated with chronic or recurrent middle ear disease. This paper reviews the current evidence concerning the involvement of bacterial biofilms in the development of chronic adenoiditis and related middle ear infections in children.

Evaluation of bacterial presence on lead X-ray aprons utilised in the operating room via IBIS and standard culture methods

Background

Despite precautions, surgical procedures carry risk of infection. Radiation-protective lead aprons worn by operating personnel are a potential source of bacterial contamination and have not been fully evaluated.

Aim/objective

To evaluate lead aprons as a source of bacterial contamination, identify organisms most commonly found on this source, and devise a method with which to lower the risk of contamination.

Methods

In this basic science study, 20 randomly selected lead X-ray aprons were swabbed at three time points. The experimental treatment was with a hospital-grade disinfectant wipe. The samples were assessed for bacterial growth via traditional plating methods and mass spectrometry. Plates were graded on a scale of 0 to 4+ based on the number of quadrants with growth. Growth on one quadrant or more was considered contaminated.

Findings/results

Bacteria were initially detected via IBIS on a majority of the aprons (32/40), most commonly Staphylococcus epidermidis and Propionibacterium acnes. Virulent organisms cultured were Methicillin-resistant Staphylococcus epidermidis (MRSE), Neisseria, Streptococcus viridans and pseudomonas. MRSE were detected on 5/20 of the samples. Immediately after treatment, the majority of aprons showed less bacterial contamination (0/20 standard culture positive; 13/20 IBIS positive) with some recurrence at the 6-h time point (2/20 standard culture positive, 16/20 IBIS positive). All MRSE detected initially was eradicated.

Discussion

Lead X-ray aprons worn in the operating room harbour bacteria. Disinfecting before use may prevent the introduction of virulent organisms to patients. Our proposed method of sanitising with a disinfectant wipe is quick and effective.

Bacterial biofilm in adenoids of children with chronic otitis media. Part I: a case control study of prevalence of biofilms in adenoids, risk factors and middle ear biofilms

BACKGROUND

Biofilms are communities of bacteria embedded in a self-produced glycocalyx matrix. Adenoids have been shown to harbor bacterial biofilms. Aim/objectives: To compare the prevalence of biofilms in adenoid of children with chronic otitis media (COM) (group1) versus a control group without any COM (group 2) having adenoids removed because of hypertrophy.

MATERIAL AND METHODS

One hundred and three children were prospectively enrolled in this case-control study, group 1 (n = 52) and group 2 (n = 51). The main outcome measurement was the prevalence of biofilm in adenoidectomy specimens analyzed using confocal laser scanning microscopy. Children in group 1 who had middle ear (ME) effusion and requiring the insertion of a tympanostomy tube underwent biopsy of the ME mucosa and effusion sampling.

RESULTS

Biofilms were found in adenoids' specimens of both groups and in the ME biopsy and effusion. The biofilm prevalence in adenoids was 63.5% (33/52) in group 1 and 47.1% (24/51) in group 2. Day nursery and previous antibiotics intake were significantly more frequent in group 1 than in group 2.

CONCLUSIONS AND SIGNIFICANCE

This case-control study demonstrates that adenoid tissue in children with COM contains more mucosal biofilms than adenoid tissue removed for hypertrophy. Biofilm was seen in ME biopsies and effusion.

Pathogen reservoir hypothesis investigated by analyses of the adenotonsillar and middle ear microbiota

INTRODUCTION

Adenotonsillar and middle ear diseases result in some of the most frequently performed operations in the pediatric population worldwide. The pathogen reservoir hypothesis (PRH) suggests that the adenoids act as a reservoir of bacteria which play a potential pathogenic role in otitis media. Evidence supporting this hypothesis is limited. This study sought to comprehensively determine and compare associations between the adenotonsillar and middle ear bacterial microbiota within individual patients via next-generation sequencing and microbial network analyses.

METHODS

Bacterial 16S rRNA gene-targeted amplicon sequencing was used to determine the bacterial composition of ten pediatric patients undergoing adenotonsillectomy and ventilation tube insertion for otitis media with effusion. At the time of surgery, swabs were taken from the adenoid surface, tonsil crypts and middle ear clefts (through the myringotomy incision).

RESULTS

The most abundant sequences within the bacterial community at genus level across all anatomical sites were Fusobacterium, Haemophilus, Neisseria, and Porphyromonas. There was an observable difference in the relative abundance of bacterial communities, with a higher proportion of Haemophilus and Moraxella in the adenoid when compared with the middle ear. Furthermore, only one module (consisting of 4 bacterial OTUs) from one patient was identified through microbial network analyses to be significantly associated between middle ear and adenoid. In addition, microbial network analysis revealed that the adenoid and tonsil microbiota share greater similarity than do the adenoid and middle ear.

CONCLUSION

The results of this study suggest that the adenoid microenvironment does not correlate to the middle ear microenvironment. A future study at the species level, and over time, is required to further investigate whether the differing relationship between the microbiota of the adenoid and middle ear rejects the pathogen reservoir hypothesis.

The Adenoids but Not the Palatine Tonsils Serve as a Reservoir for Bacteria Associated with Secretory Otitis Media in Small Children

Our findings that the microbiome differs between crypts of the adenoids and crypts of the palatine tonsils, including the relative abundances of potential pathogens such as Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis, may be the stepping stone for further investigation of individual microbiomes in a longitudinal design that includes recording of the fluctuating health status of the child. Such studies may have the potential to lead to new preventive measurements such as implantation of protective nonpathogens at the nasopharynx as an alternative to adenoidectomy.

Acute otitis media (AOM), secretory otitis media (SOM), and acute pharyngotonsillitis are the most frequent reasons for visits to general practitioners, pediatricians, and otolaryngologists. Microbial colonization of the epithelial lining of Waldeyer’s lymphatic tissues, consisting of the palatine tonsils, lingual tonsils, adenoids, and Eustachian tube tonsil, is a well-known clinical challenge during infancy due to frequent episodes of upper respiratory tract infections. However, no previous studies have investigated the combined role of the palatine tonsils and the adenoids as a reservoir for pathogens associated with SOM in small children. We analyzed the combined crypt microbiome of the palatine tonsils and adenoids from 14 small children with hyperplasia of the tonsils or adenoids and 14 small children with SOM using 16S rRNA gene pyrosequencing. Our study demonstrated a significant difference between the microbiome of the adenoids and that of the palatine tonsils in the two groups but not between the two anatomical locations within the two groups. In particular, the potential pathogens Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis were almost exclusively found in the adenoids of both patient groups, indicating that the adenoids and not the palatine tonsils are the main reservoir for potential pathogens leading to AOM and SOM.

IMPORTANCE Our findings that the microbiome differs between crypts of the adenoids and crypts of the palatine tonsils, including the relative abundances of potential pathogens such as Haemophilus influenzae, Streptococcus pneumoniae, and Moraxella catarrhalis, may be the stepping stone for further investigation of individual microbiomes in a longitudinal design that includes recording of the fluctuating health status of the child. Such studies may have the potential to lead to new preventive measurements such as implantation of protective nonpathogens at the nasopharynx as an alternative to adenoidectomy.

Biofilm production by Haemophilus influenzae and Streptococcus pneumoniae isolated from the nasopharynx of children with acute otitis media

Background

Biofilm production by Haemophilus influenzae and Streptococcus pneumoniae has been implicated in the pathogenesis of otitis media, mainly in chronic and recurrent cases. We studied the “in vitro” biofilm production by these 2 species isolated alone or together from the nasopharynx of children with acute otitis media.

Methods

The studied strains were from 3 pneumococcal conjugate vaccine (PCV) periods: pre-PCV7, post-PCV7/pre-PCV13 and post-PCV13. A modified microtiter plate assay with crystal violet stain was used to study the biofilm production of 182 H. influenzae and 191 S. pneumoniae strains.

Results

Overall, 117/181 (64.6%) H. influenzae and 128/191 (66.8%) S. pneumoniae strains produced biofilm. The proportion of biofilm-producing H. influenzae strains was greater with than without the isolation of S. pneumoniae in the same sample (75.5% vs 52.3%, p = 0.001). Conversely, the proportion of biofilm-producing S. pneumoniae strains was not affected by the presence or not of H. influenzae (66.3% vs 67.4%). S. pneumoniae serotypes 6B, 15B/C, 19A, 35F and 35B were the better biofilm producers (80%). Serotypes 11A, 14, 15A, 19F and 19A were more associated with H. influenzae biofilm-producing strains. Overall, 89/94 (94.6%) of cases with combined isolation showed biofilm production by S. pneumoniae or H. influenzae.

Conclusion

This study emphasizes the high proportion of biofilm production by H. influenzae and S. pneumoniae strains isolated from the nasopharynx of children with acute otitis media, which reinforces the results of studies suggesting the importance of biofilm in the pathogenesis of acute otitis media.

Electronic supplementary material

The online version of this article (10.1186/s12879-018-3657-9) contains supplementary material, which is available to authorized users.

Deletion of genes involved in the ketogluconate metabolism, Entner-Doudoroff pathway, and glucose dehydrogenase increase local and invasive virulence phenotypes in Streptococcus pneumoniae

Streptococcus pneumoniae displays increased resistance to antibiotic therapy following biofilm formation. A genome-wide search revealed that SP 0320 and SP 0675 (respectively annotated as 5-keto-D-gluconate-5-reductase and glucose dehydrogenase) contain the highest degree of homology to CsgA of Myxococcus xanthus, a signaling factor that promotes cell aggregation and biofilm formation. Single and double SP 0320 and SP 0675 knockout mutants were created in strain BS72; however, no differences were observed in the biofilm-forming phenotypes of mutants compared to the wild type strain. Using the chinchilla model of otitis media and invasive disease, all three mutants exhibited greatly increased virulence compared to the wild type strain (increased pus formation, tympanic membrane rupture, mortality rates). The SP 0320 gene is located in an operon with SP 0317, SP 0318 and SP 0319, which we bioinformatically annotated as being part of the Entner-Doudoroff pathway. Deletion of SP 0317 also resulted in increased mortality in chinchillas; however, mutations in SP 0318 and SP 0319 did not alter the virulence of bacteria compared to the wild type strain. Complementing the SP 0317, SP 0320 and SP 0675 mutant strains reversed the virulence phenotype. We prepared recombinant SP 0317, SP 0318, SP 0320 and SP 0675 proteins and confirmed their functions. These data reveal that disruption of genes involved in the degradation of ketogluconate, the Entner-Doudoroff pathway, and glucose dehydrogenase significantly increase the virulence of bacteria in vivo; two hypothetical models involving virulence triggered by reduced in carbon-flux through the glycolytic pathways are presented.

Clinical characteristics of obstructive sleep apnea versus infectious adenotonsillar hyperplasia in children

INTRODUCTION

Children who undergo adenotonsillectomy have a range of symptoms. Some present with infective symptoms, others with obstructive symptoms, and many with a combination of both. The most common surgical indication has changed over the past several decades from infective symptoms to obstructive symptoms. However, there are few data available to differentiate these groups of children in terms of their clinical characteristics. This study aimed to determine the clinical characteristics of children with obstructive sleep apnea versus infectious adenotonsillar hyperplasia.

METHODS

Data were obtained from the medical records of two district health boards in Auckland, New Zealand. Extraction of clinical information was performed following the identification of all patients under the age of 16 years undergoing adenotonsillectomy between December 2015 and December 2017.

RESULTS

A total of 1538 children were included in this study. There were 112 (7.3%) with recurrent tonsillitis (RT) symptoms only, 624 (40.6%) with RT and sleep-disordered breathing symptoms (SDB), and 802 (52.1%) with symptoms suggestive of obstructive sleep apnea (OSA). Children with OSA were more likely to be male (p < 0.001), younger (p < 0.001), and have lower body mass indexes at time of surgery (p < 0.001). There was no difference between groups in the number of antibiotic courses prescribed in the year before surgery (p = 0.7). There was no significant difference in tonsil or adenoid grade between groups (p = 0.2). Children with OSA were more likely to have a diagnosis of asthma (p < 0.001) and allergic rhinitis (p < 0.001), but less likely than those with RT to have a diagnosis of eczema (p < 0.001). Children with OSA were more likely to have otitis media with effusion requiring ventilation tube insertion (p < 0.001) and a documented history of speech delay (p < 0.001). Thirty-day readmission rates were higher in the OSA (8.5%) and SDB/RT (9.3%) groups when compared to those with RT (1.8%) (p = 0.03).

CONCLUSION

Children with OSA have different perioperative characteristics than those with recurrent tonsillitis, including increased risk of postoperative bleeding and need for post op readmission. Therefore, management strategy may vary according to the indications for tonsillectomy and adenoidectomy.

The Relationship between Colonization by Moraxella catarrhalis and Tonsillar Hypertrophy

We sought to investigate the prevalence of potentially pathogenic bacteria in secretions and tonsillar tissues of children with chronic adenotonsillitis hypertrophy compared to controls. Prospective case-control study comparing patients between 2 and 12 years old who underwent adenotonsillectomy due to chronic adenotonsillar hypertrophy to children without disease. We compared detection of Streptococcus pneumoniae, Haemophilus influenzae, Staphylococcus aureus, Pseudomonas aeruginosa, and Moraxella catarrhalis by real-time PCR in palatine tonsils, adenoids, and nasopharyngeal washes obtained from 37 children with and 14 without adenotonsillar hypertrophy. We found high frequency (>50%) of Haemophilus influenzae, Streptococcus pneumoniae, Moraxella catarrhalis, and Pseudomonas aeruginosa in both groups of patients. Although different sampling sites can be infected with more than one bacterium and some bacteria can be detected in different tissues in the same patient, adenoids, palatine tonsils, and nasopharyngeal washes were not uniformly infected by the same bacteria. Adenoids and palatine tonsils of patients with severe adenotonsillar hypertrophy had higher rates of bacterial coinfection. There was good correlation of detection of Moraxella catarrhalis in different sampling sites in patients with more severe tonsillar hypertrophy, suggesting that Moraxella catarrhalis may be associated with the development of more severe hypertrophy, that inflammatory conditions favor colonization by this agent. Streptococcus pneumoniae, Staphylococcus aureus, Haemophilus influenzae, and Moraxella catarrhalis are frequently detected in palatine tonsils, adenoids, and nasopharyngeal washes in children. Simultaneous detection of Moraxella catarrhalis in adenoids, palatine tonsils, and nasopharyngeal washes was correlated with more severe tonsillar hypertrophy.

Paired analysis of the microbiota between surface tissue swabs and biopsies from pediatric patients undergoing adenotonsillectomy

INTRODUCTION

Culture-independent methods, based on bacterial 16 S rRNA gene sequencing, have been used previously to investigate the adenotonsillar microbiota. However, these studies have focused on a single sampling site (usually a surface swab). We aimed to investigate potential differences in adenotonsillar microbiota according to sampling location, both on and within the adenoids and palatine tonsils.

METHODS

Pediatric patients (n = 28, mean age five years) undergoing adenotonsillectomy were recruited for this study. At the time of surgery, a mucosal adenoid surface swab and an adenoid tissue biopsy was collected. Immediately following surgery, the crypts of the right and left tonsils were swabbed, and a surface and core tissue sample from the right tonsil were also collected. Bacterial 16 S rRNA gene-targeted amplicon sequencing was used to determine the bacterial composition of the collected samples.

RESULTS

There was no significant difference in diversity or composition of the adenoid microbiota based on sampling site. However, the Shannon-Wiener and Inverse-Simpson diversity indices differed significantly (p < 0.05) between the microbial communities of the three different tonsil sampling sites. There was a higher average relative abundance of members from the genera Streptococcus, Actinobacillus, and Neisseria in the tonsil crypts when compared with surface and core tonsil tissue samples.

CONCLUSION

Our results indicate that there is variation in bacterial diversity and composition based on sampling sites in the tonsils but not the adenoids. The difference in microbiota between the surface and the tissue may have implications for our understanding of the pathogenesis of recurrent tonsillitis and have treatment implications.

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.

Preventive nasal bacteriotherapy for the treatment of upper respiratory tract infections and sleep disordered breathing in children

OBJECTIVES

The purpose of this prospective study was to assess the effectiveness and safety of Streptococcus salivarius 24SMBc administered as a nasal spray in children affected by recurring infections of the upper airways, adenotonsillar hypertrophy, and sleep disordered breathing (SDB).

METHODS

Prospective study on 42 children with SDB. Anamnestic and general examination data were collected using the 'Sleep Clinical Record' (SCR) questionnaire during the first inspection and after three months of treatment with Streptococcus salivarius 24SMBc nasal spray. Quantitative variables were statistically compared.

RESULTS

After three months, the enrolled patients showed lower SCR scores than during the first inspection (6.0 vs 7.5 p < 0.000), with a significant reduction of nasal obstruction (p = 0.001) and oral breathing (p = 0.04), and a positive Brouillette Score (p = 0.001). The children and parents did not declare any adverse reactions during the three months of treatment.

CONCLUSIONS

This series confirms the effectiveness and safety of Streptococcus salivarius 24SMBc treatment in children affected by recurring upper respiratory tract infections, adenotonsillar hypertrophy, and sleep disordered breathing.

Adenotonsillar microbiome: an update

Pathogenic bacteria associated with the adenoids and tonsils cause much morbidity in the paediatric population. Hyperplasia of the adenoids is associated with otitis media with effusion and hyperplasia of the palatine tonsils is associated with both recurrent tonsillitis and obstructive sleep apnoea. Most current knowledge of the microbiology of the upper airways has been derived from culture-based studies, which usually reflect only a small fraction of the bacteria present on the mucosal surface. Culture-independent molecular surveys based on 16S ribosomal RNA sequencing are now being employed to determine the microbiota on the surface and within the tissue of adenoids and palatine tonsils. This review describes the new techniques applied in determining the microbiome and summarises the results of studies employing these techniques.