Biofilm Formations in Pediatric Respiratory Tract Infection : Part 1: Biofilm Structure, Role of Innate Immunity in Protection Against and Response to Biofilm, Methods of Biofilm Detection, Pediatric Respiratory Tract Diseases Associated with Mucosal Biofilm Formation

Time to re-set our thinking about airways disease: lessons from history, the resurgence of chronic bronchitis / PBB and modern concepts in microbiology

In contrast to significant declines in deaths due to lung cancer and cardiac disease in Westernised countries, the mortality due to 'chronic obstructive pulmonary disease' (COPD) has minimally changed in recent decades while 'the incidence of bronchiectasis' is on the rise. The current focus on producing guidelines for these two airway 'diseases' has hindered progress in both treatment and prevention. The elephant in the room is that neither COPD nor bronchiectasis is a disease but rather a consequence of progressive untreated airway inflammation. To make this case, it is important to review the evolution of our understanding of airway disease and how a pathological appearance (bronchiectasis) and an arbitrary physiological marker of impaired airways (COPD) came to be labelled as 'diseases'. Valuable insights into the natural history of airway disease can be obtained from the pre-antibiotic era. The dramatic impacts of antibiotics on the prevalence of significant airway disease, especially in childhood and early adult life, have largely been forgotten and will be revisited as will the misinterpretation of trials undertaken in those with chronic (bacterial) bronchitis. In the past decades, paediatricians have observed a progressive increase in what is termed 'persistent bacterial bronchitis' (PBB). This condition shares all the same characteristics as 'chronic bronchitis', which is prevalent in young children during the pre-antibiotic era. Additionally, the radiological appearance of bronchiectasis is once again becoming more common in children and, more recently, in adults. Adult physicians remain sceptical about the existence of PBB; however, in one study aimed at assessing the efficacy of antibiotics in adults with persistent symptoms, researchers discovered that the majority of patients exhibiting symptoms of PBB were already on long-term macrolides. In recent decades, there has been a growing recognition of the importance of the respiratory microbiome and an understanding of the ability of bacteria to persist in potentially hostile environments through strategies such as biofilms, intracellular communities, and persister bacteria. This is a challenging field that will likely require new approaches to diagnosis and treatment; however, it needs to be embraced if real progress is to be made.

Capsular polysaccharide-amikacin nanoparticles for improved antibacterial and antibiofilm performance

Natural nanoscale polysaccharide and its application have attracted much attention in recent years. In this study, we report for the first time that a novel naturally occurring capsular polysaccharide (CPS-605) from Lactobacillus plantarum LCC-605, which can self-assemble into spherical nanoparticles with an average diameter of 65.7 nm. To endow CPS-605 with more functionalities, we develop amikacin-functionalized capsular polysaccharide (CPS) nanoparticles (termed CPS-AM NPs) with improved antibacterial and antibiofilm activities against both Escherichia coli and Pseudomonas aeruginosa. They also exhibit faster bactericidal activity than AM alone. The high local positive charge density of CPS-AM NPs facilitates the interaction between the NPs and bacteria, leading to extraordinary bactericidal efficiencies (99.9 % and 100 % for E. coli and P. aeruginosa, respectively, within 30 min) by damaging the cell wall. Very interestingly, CPS-AM NPs exhibit an unconventional antibacterial mechanism against P. aeruginosa, that is, they can induce plasmolysis, along with bacterial cell surface disruption, cell inclusion release and cell death. In addition, CPS-AM NPs exhibit low cytotoxicity and negligible hemolytic activity, showing excellent biocompatibility. The CPS-AM NPs provide a new strategy for the design of next-generation antimicrobial agents that can reduce the working concentration of antibiotics to fight against bacterial resistance.

In Vitro Assessment of Biofilm Production, Antibacterial Resistance of Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Acinetobacter spp. Obtained from Tonsillar Crypts of Healthy Adults

BACKGROUND AND OBJECTIVE

Tonsillar crypts can be considered a reservoir for a variety of bacterial species. Some bacterial species can be considered part of the normal oropharyngeal microbiota. The roles of other pathogens, for example, the so-called non-oral and respiratory pathogens Staphylococcus aureus, Klebsiella, Pseudomonas, and Acinetobacter spp., which have strong virulence factors, biofilm production capacity, and the ability to initiate infectious diseases, are unclear. The purpose of this study was to detect the presence of S. aureus, K. pneumoniae, P. aeruginosa, and Acinetobacter spp. within the tonsillar crypts of healthy individuals, and to analyze the pathogens' biofilm production and antibacterial resistances.

RESULTS

Only common oropharyngeal microbiota were cultivated from 37 participant samples (40.7%). The most commonly isolated pathogenic bacterium was S. aureus, which was isolated in 41 (45%) participant samples. K. pneumoniae was isolated in seven (7.7%) samples, Acinetobacter spp. were isolated in five (5.5%) samples, and P. aeruginosa was isolated in two (2.2%) samples. Biofilm producers predominated among the pathogenic bacteria; 51 strains were biofilm producers, and among them, 31 strains were moderate or strong biofilm producers. The tested S. aureus, K. pneumoniae, P. aeruginosa, and Acinetobacter spp. strains were sensitive to commonly used antibiotics (amoxicillin-clavulanic acid, clindamycin, or ciprofloxacin). One of the isolated S. aureus strains was MRSA.

CONCLUSIONS

Biofilm is a commonly observed feature that seems to be a naturally existing form of pathogenic bacteria colonizing human tissue. S. aureus, K. pneumoniae, P. aeruginosa, and Acinetobacter spp. occasionally occur in the tonsillar crypts of healthy individuals, and, therefore, it is most likely that S. aureus, K. pneumoniae, P. aeruginosa, and Acinetobacter spp. in opportunistic tonsillar infections originate from the tonsillar crypt microbiota.

Analysis of Tonsil Tissues from Patients Diagnosed with Chronic Tonsillitis-Microbiological Profile, Biofilm-Forming Capacity and Histology

Chronic tonsillitis (CT) is a global health issue which can impair patient's quality of life and has an important socioeconomic impact due to the nonrational use of antibiotics, increased antimicrobial resistance and frequent need for surgical treatment. In order to isolate and identify the causing agents of CT, a total of 79 postoperative palatine and adenoid tissue samples were obtained from the ENT Clinic, KBC Zvezdara, Belgrade, Serbia. Culture identification was performed by MALDI-TOF MS and the Staphylococcus aureus isolates were tested for biofilm forming capability and antibiotic susceptibility. Additionally, a histological examination of palatine and adenoid tissue was performed in order to detect the presence of CT-causing bacteria. The slight majority of participants were females with median age of 28 years for adult patients (group I) and 6 years for children (group II). Analysis of the incidence of bacteria isolated from tissue samples in both groups showed the highest prevalence of S. aureus, Streptococcus oralis and Streptococcus parasanquinis. In addition to interfollicular hyperplasia, colonies of species S. aureus were detected in histological material. The presence of biofilm might be the reason for the recurrence of infection. Therefore, searching for a new treatment of CT is of great importance.

A review on the physicochemical and biological applications of biosurfactants in biotechnology and pharmaceuticals

Biosurfactants are the chemical compounds that are obtained from various micro-organisms and possess the ability to decrease the interfacial tension between two similar or different phases. The importance of biosurfactants in cosmetics, pharmaceuticals, biotechnology, agriculture, food and oil industries has made them an interesting choice in various physico-chemical and biological applications. With the aim of representing different properties of biosurfactants, this review article is focused on emphasizing their applications in various industries summarizing their importance in each field. Along with this, the production of recently developed chemically and biologically important biosurfactants has been outlined. The advantages of biosurfactants over the chemical surfactants have also been discussed with emphasis on the latest findings and research performed worldwide. Moreover, the chemical and physical properties of different biosurfactants have been presented and different characterization techniques have been discussed. Overall, the review article covers the latest developments in biosurfactants along with their physico-chemical properties and applications in different fields, especially in pharmaceuticals and biotechnology.

The Correlation Between Biofilm-Forming Ability of Community-Acquired Methicillin-Resistant Staphylococcus aureus Isolated from the Respiratory Tract and Clinical Characteristics in Children

Objective

This study aimed to investigate the biofilm-forming ability, molecular typing, and antimicrobial resistance of community-acquired methicillin-resistant Staphylococcus aureus (CA-MRSA) strains isolated from the respiratory tract of children and their correlation with clinical characteristics.

Methods

All CA-MRSA strains were isolated from hospitalized children, and their presentation, molecular typing, antimicrobial susceptibility, and biofilm formation were investigated. The clinical characteristics were compared between the strong and weak biofilm producer groups.

Results

Fifty-three CA-MRSA strains were isolated from the respiratory samples of 53 children, with nearly half of them being young infants (0-12 months). Approximately, 88.7% (47/53) of the isolates were resistant to four or more antibiotics, mainly β-lactam antibiotics, lincosamides, and macrolides. Twelve sequence types (STs) and 20 subtypes of staphylococcal protein A (spa) typing were identified, with ST59-t437 (39.6%, 21/53) as the predominant subtype. All strains showed the ability to form biofilms. When compared to children with weak biofilm-forming CA-MRSA strains, those with strong biofilm-forming strains had higher proportions of lower respiratory tract infections (LRTI) (88.5% vs 59.3%), obvious cough symptoms (84.6% vs 51.9%), and severe chest imaging manifestations (76.9% vs 37.0%). Furthermore, a strong biofilm-forming ability significantly increased the risk of prolonged cough in children with LRTI (44.4% vs 14.3%), and a positive correlation between the duration of cough and the extent of biofilm formation was observed. Medical history investigation revealed that the strong biofilm-forming group had a much higher percentage of macrolides intake than the weak biofilm-forming group in the last month before admission (61.5% vs 14.8%).

Conclusion

ST59-t437 was the most prevalent clone in CA-MRSA respiratory isolates among the hospitalized children. All CA-MRSA strains formed biofilms. The stronger the biofilm-forming ability, the more serious and prolonged were the respiratory symptoms.

The Current Knowledge on the Pathogenesis of Tissue and Medical Device-Related Biofilm Infections

Biofilm is the trigger for the majority of infections caused by the ability of microorganisms to adhere to tissues and medical devices. Microbial cells embedded in the biofilm matrix are highly tolerant to antimicrobials and escape the host immune system. Thus, the refractory nature of biofilm-related infections (BRIs) still represents a great challenge for physicians and is a serious health threat worldwide. Despite its importance, the microbiological diagnosis of a BRI is still difficult and not routinely assessed in clinical microbiology. Moreover, biofilm bacteria are up to 100–1000 times less susceptible to antibiotics than their planktonic counterpart. Consequently, conventional antibiograms might not be representative of the bacterial drug susceptibility in vivo. The timely recognition of a BRI is a crucial step to directing the most appropriate biofilm-targeted antimicrobial strategy.

Clearance of mixed biofilms of Streptococcus pneumoniae and methicillin-susceptible/resistant Staphylococcus aureus by antioxidants N-acetyl-L-cysteine and cysteamine

Biofilm-associated infections are of great concern because they are associated with antibiotic resistance and immune evasion. Co-colonization by Staphylococcus aureus and Streptococcus pneumoniae is possible and a threat in clinical practice. We investigated the interaction between S. aureus and S. pneumoniae in mixed biofilms and tested new antibiofilm therapies with antioxidants N-acetyl-l-cysteine (NAC) and cysteamine (Cys). We developed two in vitro S. aureus–S. pneumoniae mixed biofilms in 96-well polystyrene microtiter plates and we treated in vitro biofilms with Cys and NAC analyzing their effect by CV staining and viable plate counting. S. pneumoniae needed a higher proportion of cells in the inoculum and planktonic culture to reach a similar population rate in the mixed biofilm. We demonstrated the effect of Cys in preventing S. aureus biofilms and S. aureus–S. pneumoniae mixed biofilms. Moreover, administration of 5 mg/ml of NAC nearly eradicated the S. pneumoniae population and killed nearly 94% of MSSA cells and 99% of MRSA cells in the mixed biofilms. The methicillin resistance background did not change the antioxidants effect in S. aureus. These results identify NAC and Cys as promising repurposed drug candidates for the prevention and treatment of mixed biofilms by S. pneumoniae and S. aureus.

Biofilm and Planktonic Antibiotic Resistance in Patients With Acute Exacerbation of Chronic Rhinosinusitis

INTRODUCTION

The recalcitrant nature of patients with acute exacerbation of chronic rhinosinusitis (AECRS) potentially involves persisting colonization of the sinonasal mucosa by bacterial biofilms. Biofilms are known to be highly resistant to antibiotics, which may trigger or maintain chronic inflammation in the sinonasal mucosa. However, little is known about the relationship between the minimum inhibitory concentration (MIC) and antibiofilm concentrations of bacteria obtained from AECRS patients.

MATERIAL AND METHODS

Thirty bacterial strains from 25 patients with AECRS were identified and underwent MIC determination (VITEK^® 2). The planktonic isolates were submitted to an in vitro formation of biofilms (Modified Calgary Biofilm Device) and determination of minimum biofilm inhibitory concentration (MBIC) and minimum biofilm eradication concentration (MBEC) for amoxicillin, amoxicillin/clavulanic acid, clarithromycin, and levofloxacin. MIC of the planktonic forms was compared with MBIC and MBEC levels, according to the breakpoints established by the Clinical Laboratory Standards Institute guidelines.

RESULTS

The main bacteria retrieved was S. aureus (60%), followed by other Gram-positive and Gram-negative bacteria in lower frequencies. 76.7% of strains formed biofilm in vitro (n=23/30). The planktonic isolates presented high rates of resistance for amoxicillin (82.6%) and clarithromycin (39.1%), and lower rates for amoxicillin/clavulanic acid (17.4%). The biofilm-forming bacteria counterparts presented higher levels of MBIC and MBEC compared to the MIC levels for amoxicillin, amoxicillin/clavulanic acid, and clarithromycin. Levofloxacin was highly effective against both planktonic and biofilm forms. Planktonic resistant forms were associated with levels of antibiofilm concentrations (MBIC and MBEC).

CONCLUSIONS

Biofilm-forming bacteria from AECRS patients are prevalent, and biofilm forms are highly resistant to antibiotics compared to their planktonic counterparts. Antibiotic resistance observed in planktonic forms is a good indicator of biofilm resistance, although near 20% of susceptible planktonic bacteria can produce antibiotic tolerant biofilms.

Perillaldehyde mitigates virulence factors and biofilm formation of Pseudomonas aeruginosa clinical isolates, by acting on the quorum sensing mechanism in vitro

AIM

The incidence of biofilm linked catheter-associated urinary tract infections (CAUTIs) are increasing worldwide and Pseudomonas aeruginosa is one of the major causes. Perillaldehyde (PLD): as a natural, widely used flavouring agent, has been reported to possess various pharmacological properties. We hypothesized that PLD can inhibit biofilm formation and virulence factor production by P. aeruginosa by hampering the quorum sensing (QS) system(s).

METHODS AND RESULTS

Minimum inhibitory concentration (MIC) of PLD was assessed for standard strain and two multi-drug resistant catheter isolates of P. aeruginosa utilizing the microdilution method. Microtiter plate assay, crystal violet staining and scanning electron microscopy were used to evaluate the biofilm inhibition property. CFU was utilized to assess the antifouling property of PLD. Detection of virulence factors (VFs) and expression analysis of virulence determinants were applied to investigate the anti-virulence activity. Gene expression and molecular docking studies were also executed to explore the QS inhibition and binding of PLD with QS receptors. In the present study, PLD has significantly inhibited biofilm formation and antivirulence activity at sub-MIC levels (2.5 mM and 3.5 mM) in all the tested strains. In addition, molecular docking studies revealed a significant affinity towards quorum sensing receptors.

DISCUSSIONS

Perillaldehyde (PLD), being a non-toxic food flavouring agent, significantly inhibited biofilm formation, and exhibited antifouling property. PLD exhibited significantly reduced levels of VFs (p<0.001) and their respective genetic determinants (p<0.001). Gene expression analysis and molecular docking studies confirmed the interactions of PLD to the QS receptors, indicating the plausible mechanism for the anti-virulence property.

SIGNIFICANCE AND IMPACT OF STUDY

This study identified the anti-virulence potential of PLD and provided mechanistic insights. Perillaldehyde can be a suitable, non-toxic candidate for countering biofilms and associated pathogens, contributing to the prevention of biofilm-associated nosocomial infections..

Biofilm formation and molecular analysis of intercellular adhesion gene cluster (icaABCD) among Staphylococcus aureus strains isolated from children with adenoiditis

Background and Objectives:

It is well known that Staphylococcus aureus biofilm plays an important role in adenoiditis and biofilm resistance frequently results in failure of therapy. The goal of this study was to evaluate the biofilm production of S. aureus isolates obtained from adenoid specimens and assess the relationship between biofilm formation ability and ica operon genes.

Materials and Methods:

A total of 112 adenoid samples were obtained from patients under 15 years old with adenoid hypertrophy. All S. aureus isolates were initially identified by standard microbiological tests and amplification of nuc by polymerase chain reaction (PCR) technique. Biofilm formation of S. aureus isolates was evaluated and icaADBC genes were detected by PCR technique.

Results:

There were 46 isolates (41%) identified as S. aureus. The ability to produce biofilm was detected among total S. aureus isolates. Molecular study of ica operon revealed that 2 (6.3%) and 19 (59.4%) isolates carried icaA and icaD, respectively. The prevalence of icaA + icaD was seen among 11 (34.4%) S. aureus isolates, while icaC and icaB were not detected.

Conclusion:

Our findings indicated that icaABCD operon are associated with biofilm formation in S. aureus isolates, however the absence of these genes may not necessarily exclude this property.

Impact of COVID-19 pandemic on the incidence of otitis media with effusion in adults and children: a multicenter study

Purpose

To compare and analyze the incidence of otitis media with effusion (OME), before and during the COVID-19-related pandemic period, to evaluate the effects of the social changes (lockdown, continuous use of facial masks, social distancing, reduction of social activities) in the OME incidence in children and adults.

Methods

The number of diagnosed OME in e five referral centers, between 1 March 2018 and 1 March 2021, has been reviewed and collected. To estimate the reduction of OME incidence in children and adults during the COVID-19 pandemic period the OME incidence in three period of time were evaluated and compared: group 1—patients with OME diagnosis achieved between 1/03/2018 and 01/03/2019 (not pandemic period). Group 2—patients with OME diagnosis achieved between 1/03/2019 and 1/03/2020 (not pandemic period). Group 3—patients with OME diagnosis achieved between 1/03/2020 and 1/03/2021 (COVID-19 pandemic period).

Results

In the non-pandemic periods (group 1 and 2), the incidence of OME in the five referral centers considered was similar, with 482 and 555 diagnosed cases, respectively. In contrast, the OME incidence in the same centers, during the pandemic period (group 3) was clearly reduced with a lower total number of 177 cases of OME estimated. Percentage variation in OME incidence between the first non-pandemic year considered (group 1) and the pandemic period (group 3) was—63, 3%, with an absolute value decrease value of—305 cases. Similarly, comparing the second non-pandemic year (group 2) and the pandemic year (group 3) the percentage variation of OME incidence was—68, 1% with an absolute value of—305 cases decreased.

Conclusions

Our findings showed a lower incidence of OME during the pandemic period compared with 2 previous non pandemic years. The drastic restrictive anti-contagion measures taken by the Italian government to contain the spread of COVID-19 could have had a positive impact on the lower OME incidence during the last pandemic year.

Effects of the Traditional Mediterranean Diet in Patients with Otitis Media with Effusion

INTRODUCTION

Otitis media with effusion (OME) is common in pediatric primary care consultations. Its etiology is multifactorial, although it has been proven that inflammation factors mediate and that immunity is in a phase of relative immaturity. The objective of this study was to assess the effects of the Traditional Mediterranean Diet (TMD) modulating inflammation and immunity in patients diagnosed with OME.

MATERIALS AND METHODS

A analysis as a single-group pre-test/post-test was conducted on 40 girls and 40 boys between 18 months and 5 years old. Tympanometry normalization was the main test to control the benefit of diet. Clinical and therapeutic variables were studied through evaluation questionnaires, a quality test of the diet, as well as various anthropometric parameters.

RESULTS

At the end of one year, tympanometry had normalized in 85% of patients. The remaining 15% had normal audiometry and/or associated symptoms had decreased. Likewise, episodes of recurrent colds decreased from 5.96 ± 1.41 to 2.55 ± 0.37; bacterial complications of 3.09 ± 0.75 to 0.61 ± 0.06 and persistent nasal obstruction of 1.92 ± 0.27 to 0.26 ± 0.05. The degree of satisfaction of the families with the program was very high.

CONCLUSIONS

The application of the Traditional Mediterranean Diet could have promising effects in the prevention and treatment of otitis media with effusion.

Mimicking biofilm formation and development: Recent progress in in vitro and in vivo biofilm models

Biofilm formation in living organisms is associated to tissue and implant infections, and it has also been linked to the contribution of antibiotic resistance. Thus, understanding biofilm development and being able to mimic such processes is vital for the successful development of antibiofilm treatments and therapies. Several decades of research have contributed to building the foundation for developing in vitro and in vivo biofilm models. However, no such thing as an "all fit" in vitro or in vivo biofilm models is currently available. In this review, in addition to presenting an updated overview of biofilm formation, we critically revise recent approaches for the improvement of in vitro and in vivo biofilm models.

Phenotypes of Chronic Rhinosinusitis

Chronic rhinosinusitis (CRS) is a complex heterogeneous disease with different phenotypes and endotypes. Recent advances in our understanding of the pathogenetic mechanisms of CRS endotypes have led to the introduction of effective biologic agents for CRS management. Traditionally, CRS phenotypes have been divided into with or without nasal polyps depending on the presence of polyps. Although this classification does not reflect the various endotypes that are recently emerging, it is simple and easily recognized by clinicians. Other phenotypes of CRS are fungal rhinosinusitis (including invasive and noninvasive subtypes), infectious rhinosinusitis, aspirin-exacerbated respiratory disease, cystic fibrosis, pediatric CRS, and CRS associated with systemic diseases. This article reviews the diagnostic approaches and up-to-date treatment strategies for each CRS phenotype with the hope that a better understanding of endotypes will result in a more scientific understanding of phenotypes and precise, personalized treatments.

Biofilm inhibition and antifouling evaluation of sol-gel coated silicone implants with prolonged release of eugenol against Pseudomonas aeruginosa

The incidence of biofilm-linked catheter-associated urinary tract infections (CAUTIs) is increasing across the world. However, there is no clinical evidence to support the modifications of biomaterials, such as antimicrobial agent-coated catheters, that are known to reduce the risk of bacterial colonization and resistance development. The present study developed and tested silicone segments coated with an antivirulence agent, eugenol. The parameters for sol-gel preparation and coating were tailored to achieve a prolonged release of eugenol (for >35 days) at predefined antivirulence doses from dip-coated thin films. The eugenol-coated segments could prevent biofilm formation by Pseudomonas aeruginosa PAO1 as well as bacterial adhesion. Significant repression in the expression of virulence and biofilm-associated genes were recorded, confirming the antivirulence and biofilm inhibition properties of silicone segments coated with eugenol. The drug release profiles, efficacy analysis, neutrophil-response studies, and in vitro toxicity profiling further supported the contention that the activity of the eugenol-coated sections was effective and safe.

Impact of Isolation on Adenoid Size and Symptoms in Preschool Children Who Previously Qualified for Adenoidectomy: A Case-Control Study

OBJECTIVES

To analyze the role of factors that influence adenoid-related symptoms, and the influence of 3 months of isolation in preschool children who were qualified for adenoidectomy.

METHODS

This was a cohort study of the impact of 3 months of isolation on children aged 3 to 6 years with adenoid-related symptoms and endoscopically confirmed grade II and III adenoid hypertrophy. The children had previously qualified for adenoidectomy. After 3 months, 141 children were asked about their symptoms, 71 of whom were randomly chosen for medical examination, including endoscopic adenoid examination. Additionally, pre- and post-isolation tympanometry results were analyzed.

RESULTS

In our study, significant or mild improvements in health were observed in approximately 73% of the children; 92% of the surveyed parents reported that their children exhibited improved nasal patency, 63% of children discontinued snoring, and 30% of children showed a decrease in snoring. Data collected through surveys correlated with endoscopic findings wherein the size of the adenoid decreased by an average of 5.4%, but the amount of mucus covering the adenoid decreased more significantly in 76% of patients, which may be the main problem determining symptoms reported before isolation. In addition, the amount of residual mucus in the nasopharynx significantly affected the middle ear effusion in adenoid hypertrophy.

CONCLUSIONS AND RELEVANCE

This study found that isolation in preschool children stabilizes the bacterial microbiome of the nose and nasopharynx, thereby having a significant effect not only on the number of recurrent infections of the upper respiratory tract but also on the patency of the nose. The only symptom that depended on the size of the pharyngeal tonsil hypertrophy was snoring. There was a weak correlation between prevalence of infections and adenoid size. During the isolation period, the adenoid size reduced by approximately 5.4% only, statistically more significant in the group with grade III adenoid hypertrophy, but the prevalence of infections rapidly decreased. Residual mucous in the nasopharynx found to be in correlation with middle ear effusion.

Biofilm distribution on tympanostomy tubes: An ex vivo descriptive study

BACKGROUND

Tympanostomy tube (TT) insertion is a common procedure in children with otitis media with effusion. Post-TT otorrhea (PTTO) is a frequent post-operative complication. Biofilms are involved in chronic PTTO cases.

OBJECTIVE

To describe and qualitatively analyze the geometry and sites prone to biofilms on removed TTs, relatively to their position in the ear, past medical/surgical history and PTTO presence.

METHODS

Biofilms presence and topographic distribution on TTs were ex vivo evaluated by using scanning electron microscope, confocal microscope and stereo-microscope.

RESULTS

Forty-eight TTs from 30 children were analyzed. Indications for removal were: 71% due to retained TTs (average time from insertion: 24.4 ± 15.1 months), 23% due to chronic PTTO, and 6% due to TT obstruction/dysfunction. Different types of bacterial biofilms were detected on all TTs, regardless the time from their insertion nor their types. Biofilms were observed more on the perpendicular junction and on the internal lumen, and more biofilm colonies were detected on the medial part, facing the middle ear mucosa. TTs removed from children with PTTO exhibited more biofilm colonies when compared to their peers. Of the 16 children who underwent adenoidectomy concomitantly with TT insertion, 10 (62%) children were sent for TT removal due to retained TTs, and 6 (38%) children due to chronic PTTO (p = 0.03).

CONCLUSION

Descriptive analysis of biofilm topographic distribution demonstrated adhesions on specific TT areas: perpendicular junctions and the internal lumen. Such "prone zones" may be the future target areas for changes in TT geometry or can be specifically coated with anti-biofilm materials.

Effectiveness of TCM cauterization in recurrent tonsillitis: A protocol for systematic review and meta-analysis

INTRODUCTION

Recurrent tonsillitis (RT) is often treated with antibiotic therapy and surgery. Although these treatments have advantages, they are also controversial. The purpose of this study is to analyze the safety and effectiveness of traditional Chinese medicine (TCM) cauterization in the treatment of RT, so as to provide an alternative for the clinicians and to cover the shortage of therapeutic methods.

METHODS AND ANALYSIS

This protocol is guided by the Preferred Reporting Items for Systematic Review and Meta-Analysis Protocols (PRISMA-P) and by the Cochrane Collaboration Handbook. We will formulate strict inclusion and exclusion criteria in English databases (PubMed, EMBASE, and Web of Science), Chinese databases (CNKI, Wanfang databases, CBM, and VIP), and search literatures in different clinical registration platforms (Cochrane Library, Chinese Cochrane Centre's Clinical Trial Registry Platform). The included articles will be evaluated using Cochrane RCT evaluation criteria. Stata 15.0 will be used for data analysis. Subgroup analysis, sensitivity analysis, and meta-regression will detect sources of heterogeneity. Egger's Test or Begg's Test will detect publication bias quantitatively.

CONCLUSION

Cauterization can effectively control the recurrence of tonsillitis through clinical trials, but evidence-based medicine needs to be adopted to provide strong evidence for its effectiveness. The purpose of our research is to provide the evidence.

OSF REGISTRATION NUMBER

DOI 10.17605/OSF.IO/PZ69Q.

Unsolved problems and new medical approaches to otitis media

INTRODUCTION

Otitis media (OM) is a spectrum of infectious and inflammatory diseases that involve the middle ear. It includes acute otitis media (AOM), otitis media with effusion (OME) and chronic suppurative otitis media (CSOM).

AREAS COVERED

This manuscript discusses some of the emerging and unsolved problems regarding OM, and some of the newly developed prophylactic and therapeutic medical measures.

EXPERT OPINION

In recent years, considerable progress in the knowledge of OM physiopathology has been made. However, although extremely common, diseases included under OM have not been adequately studied, and many areas of development, evolution and possible treatments of these pathologies are not defined. It is necessary that these deficiencies be quickly overcome if we want to reduce the total burden of a group of diseases that still have extremely high medical, social and economic relevance.

Biologics in chronic rhinosinusitis with nasal polyposis

OBJECTIVE

Chronic rhinosinusitis with nasal polyps (CRSwNP) is a common and heterogeneous inflammatory condition, for which the drivers of the underlying inflammation are not yet fully understood. The use of biologic therapies to target specifically relevant effector cells or cytokines in CRSwNP is a growing field of interest. The objectives of this review are to provide an update on the existing studies of biologics in CRSwNP and to identify potential future areas for further research.

DATA SOURCES

An initial literature review of biologic therapies in CRS was performed through publications gathered from a PubMed search for title/abstract containing "biologic" and "chronic rhinosinusitis." Further manuscripts describing scientific premise for each biologic were then reviewed.

STUDY SELECTIONS

A detailed review of all studies describing biologic therapies targeting inflammation in CRSwNP was performed.

RESULTS

Biologic therapies targeting interleukin (IL)-4Rα, IL-5, IL-5Rα, IL-33, immunoglobulin (Ig)E, and thymic stromal lymphopoietin (TSLP) have all been developed and have been investigated for treatment in CRSwNP, or current research suggests that they may have utility in this area. Only dupilumab, which inhibits IL-4Rα, has gained Food and Drug Administration approval for the treatment of adults with inadequately controlled CRSwNP.

CONCLUSION

Recent advances in our understanding of the fundamental drivers of the chronic respiratory inflammation in CRSwNP has led to the identification of several potential therapeutic targets for this disease. Future clinical success will rely on the availability of biomarker-based endotyping and responder analyses so that clinicians can precisely match each patient to the appropriate biologic, thereby optimizing the proper treatment strategy.

Panel 7 - Pathogenesis of otitis media - a review of the literature between 2015 and 2019

OBJECTIVE

To perform a comprehensive review of the literature from July 2015 to June 2019 on the pathogenesis of otitis media. Bacteria, viruses and the role of the microbiome as well as the host response are discussed. Directions for future research are also suggested.

DATA SOURCES

PubMed database of the National Library of Medicine.

REVIEW METHODS

PubMed was searched for any papers pertaining to OM pathogenesis between July 2015 and June 2019. If in English, abstracts were assessed individually for their relevance and included in the report. Members of the panel drafted the report based on these searches and on new data presented at the 20th International Symposium on Recent Advances in Otitis Media.

CONCLUSIONS

The main themes that arose in OM pathogenesis were around the need for symptomatic viral infections to develop disease. Different populations potentially having different mechanisms of pathogenesis. Novel bacterial otopathogens are emerging and need to be monitored. Animal models need to continue to be developed and used to understand disease pathogenesis.

IMPLICATIONS FOR PRACTICE

The findings in the pathogenesis panel have several implications for both research and clinical practice. The most urgent areas appear to be to continue monitoring the emergence of novel otopathogens, and the need to develop prevention and preventative therapies that do not rely on antibiotics and protect against the development of the initial OM episode.