Prospective evaluation of the aetiology of acute otitis media with spontaneous tympanic membrane perforation

A Systematic Review and Meta-Analysis of the Efficacy of Antimicrobial Chemoprophylaxis for Recurrent Acute Otitis Media in Children

OBJECTIVES

Acute otitis media (AOM) is a common childhood infection. Recurrent AOM affects a subset of children, resulting in an adverse impact on quality of life, socioeconomic disadvantage, and risk of long-term sequelae. Antimicrobial chemoprophylaxis is used in some settings but is increasingly controversial due to an awareness of adverse long-term effects and contribution to global antibiotic resistance.

DESIGN AND SETTING

A comprehensive literature search was undertaken using Medline (1946-October 2023) and Embase (1974-October 2023). The primary aim was to assess the efficacy of antimicrobial chemoprophylaxis on AOM episodes in children < 18 years of age. Bias and quality assessment was performed. Dichotomous data were analysed using risk ratio with 95% confidence intervals. Meta-analysis was carried out using random-effects models for pooled analysis, independent of heterogeneity. Heterogeneity was assessed using the I 2 statistic.

MAIN OUTCOME MEASURES

The effect of antimicrobial chemoprophylaxis in children with rAOM on the number of individual AOM episodes.

SECONDARY OUTCOMES

assessment of antimicrobial agents and outcomes in children with risk factors.

RESULTS

Assessment of qualitative data was performed on 20 studies (n = 2210). No controlled trials were identified post-multivalent pneumococcal conjugate vaccine (PCV) introduction, restricting current generalisability. Quantitative meta-analysis on nine pre-PCV studies (n = 1087) demonstrated antimicrobial chemoprophylaxis reduced any episode of AOM with a risk ratio 0.59 (95% CI 0.45-0.77).

CONCLUSION

Families and clinicians must balance marginal short-medium term benefit (based on pre-PCV data), and the potential for adverse effects to that individual, and the societal risk of antimicrobial resistance with prolonged antibiotic use.

A Trivalent Live Vaccine Elicits Cross-Species Protection Against Acute Otitis Media in a Murine Model

Background: Acute otitis media (AOM) is a common pediatric infection worldwide and is the primary basis for pediatric primary care visits and antibiotic prescriptions in children. Current licensed vaccines have been incompletely ineffective at reducing the global burden of AOM, underscoring a major unmet medical need. The complex etiology of AOM presents additional challenges for vaccine development, as it can stem from multiple bacterial species including Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis. As such, targeting multiple pathogens simultaneously may be required to significantly impact the overall disease burden. Methods: In this study, we aim to overcome this challenge by engineering a live-attenuated vaccine platform based on an attenuated mutant of S. pneumoniae that expresses H. influenzae and M. catarrhalis surface epitopes to induce protective immunity against all three pathogens. Results: The trivalent live-attenuated vaccine conferred significant protection against all three bacterial otopathogens as measured by seroconversion and the development of AOM, with the inclusion of the additional epitopes providing unexpected synergy and enhanced protection against S. pneumoniae. Conclusions: These data demonstrate a novel mechanism of introducing non-native immunogenic antigens into a live-attenuated vaccine platform to engender protection against AOM from multiple pathogenic species.

Clinical and economic burden of acute otitis media caused by Streptococcus pneumoniae in European children, after widespread use of PCVs-A systematic literature review of published evidence

BACKGROUND

Acute otitis media (AOM) is a common childhood disease frequently caused by Streptococcus pneumoniae. Pneumococcal conjugate vaccines (PCV7, PCV10, PCV13) can reduce the risk of AOM but may also shift AOM etiology and serotype distribution. The aim of this study was to review estimates from published literature of the burden of AOM in Europe after widespread use of PCVs over the past 10 years, focusing on incidence, etiology, serotype distribution and antibiotic resistance of Streptococcus pneumoniae, and economic burden.

METHODS

This systematic review included published literature from 31 European countries, for children aged ≤5 years, published after 2011. Searches were conducted using PubMed, Embase, Google, and three disease conference websites. Risk of bias was assessed with ISPOR-AMCP-NPC, ECOBIAS or ROBIS, depending on the type of study.

RESULTS

In total, 107 relevant records were identified, which revealed wide variation in study methodology and reporting, thus limiting comparisons across outcomes. No homogenous trends were identified in incidence rates across countries, or in detection of S. pneumoniae as a cause of AOM over time. There were indications of a reduction in hospitalization rates (decreases between 24.5-38.8% points, depending on country, PCV type and time since PCV introduction) and antibiotic resistance (decreases between 14-24%, depending on country), following the widespread use of PCVs over time. The last two trends imply a potential decrease in economic burden, though this was not possible to confirm with the identified cost data. There was also evidence of an increase in serotype distributions towards non-vaccine serotypes in all of the countries where non-PCV serotype data were available, as well as limited data of increased antibiotic resistance within non-vaccine serotypes.

CONCLUSIONS

Though some factors point to a reduction in AOM burden in Europe, the burden still remains high, residual burden from uncovered serotypes is present and it is difficult to provide comprehensive, accurate and up-to-date estimates of said burden from the published literature. This could be improved by standardised methodology, reporting and wider use of surveillance systems.

The burden of antibiotic resistance of the main microorganisms causing infections in humans - review of the literature

One of the biggest threats to human well-being and public health is antibiotic resistance. If allowed to spread unchecked, it might become a major health risk and trigger another pandemic. This proves the need to develop antibiotic resistance-related global health solutions that take into consideration microdata from various global locations. Establishing positive social norms, guiding individual and group behavioral habits that support global human health, and ultimately raising public awareness of the need for such action could all have a positive impact. Antibiotic resistance is not just a growing clinical concern but also complicates therapy, making adherence to current guidelines for managing antibiotic resistance extremely difficult. Numerous genetic components have been connected to the development of resistance; some of these components have intricate paths of transfer between microorganisms. Beyond this, the subject of antibiotic resistance is becoming increasingly significant in medical microbiology as new mechanisms underpinning its development are identified. In addition to genetic factors, behaviors such as misdiagnosis, exposure to broad-spectrum antibiotics, and delayed diagnosis contribute to the development of resistance. However, advancements in bioinformatics and DNA sequencing technology have completely transformed the diagnostic sector, enabling real-time identification of the components and causes of antibiotic resistance. This information is crucial for developing effective control and prevention strategies to counter the threat.

Short-term antibiotic therapy for the most common bacterial respiratory infections in infants and children

Overuse and misuse of antibiotics have strongly accelerated the progressive increase in bacterial antimicrobial resistance (AMR). The evidence that antimicrobial selective pressure was greater the longer the antibiotic therapy was continued has led some experts to reconsider duration of antibiotic therapy testing the use of short-term drug administration. If as effective as long-term therapy, short-term therapy could have been an easy measure to limit AMR emergence. In the present narrative review, whether present knowledge on short-term therapy of acute streptococcal pharyngitis (ASF), acute otitis media (AOM) and mild to moderate community-acquired pneumonia (CAP) allows systematic use of short-term therapy in infants and children with these diseases is discussed. Literature analysis showed that reducing the duration of antibiotic therapy for some of the most common pediatric respiratory infections could be a valid measure to contain the antibiotic abuse and the consequent impact on the emergence of AMR. Several data seem to indicate that this type of intervention is possible, as short-term therapy has been found as effective as the traditionally recommended long-term therapy in some cases of ASF, AOM and mild to moderate CAP. However, further studies are needed to better characterize infants and children who can have benefit with short-term antibiotic therapy in common bacterial respiratory infections.

Recurrent Acute Otitis Media Could Be Related to the Pro-Inflammatory State That Causes an Incorrect Diet

Introduction: Acute Otitis Media (AOM) is the most commonly-occurring bacterial complication in childhood. After making certain corrections to the patients’ dietary habits, which we found to be excessively high in animal-based and industrially-processed foods, we observed a significant reduction in recurrent colds and their bacterial complications. We promote an original way of treating these diseases, since until now the conventional treatment is based on pharmacological and surgical treatment. From our point of view, the mucosa that covers the entire ENT area is in a pro-inflammatory and hyper-reactive state, as a consequence of the alterations produced by an inadequate diet. For us there is no difference in the nutritional treatment of the different mucous membranes that cover the ENT area. The purpose of the study was to assess the effects of the Traditional Mediterranean Diet (TMD) on patients diagnosed with Recurring Acute Otitis Media (RAOM). Methods: prospective pre-postest comparison study with 48 girls and 42 boys aged 1–5 years, each of whom had been and included on the 1-year programme “Learning to eat the Mediterranean Way”, designed to encourage the adoption of the TMD. We studied clinical and therapeutic variables and various anthropometric parameters. Results: all the symptomatic indicators studied (number and intensity of episodes of otitis and emergency admissions) showed a positive and statistically significant evolution in RAOM. By the end of the study, none of the patients met the criteria for classification as RAOM, and 60% percent of patients did not present any further episodes of AOM. In line with the above, the use of anti-microbial drugs and symptomatic treatments reduced considerably; the use of antibiotics dropped from 4.30 occasions/patient/year, to 0.66 (p < 0.001), and the used of symptomatic treatments dropped from 7.63 to 2.75 (p < 0.001). The level of family satisfaction was very high. Conclusions: the adoption of the Traditional Mediterranean Diet has been demonstrated to significantly reduce occurrence of acute otitis media and may contribute to the treatment of patients diagnosed with recurrent acute otitis media.

Evaluation of acoustic changes in and the healing outcomes of rat eardrums with pars tensa and pars flaccida perforations

OBJECTIVES

To systematically explore the differences in acoustic changes and healing outcomes of tympanic membranes (TMs) with pars flaccida perforation (PFP) and pars tensa perforation (PTP).

METHODS

We created PFPs and PTPs of various sizes in Sprague-Dawley rats, and evaluated TM umbo velocity and hearing function using laser Doppler vibrometry and auditory brainstem response (ABR) measurement before and immediately after perforation. Two weeks later, hearing was reevaluated and TMs were investigated by immunohistochemical staining.

RESULTS

Small PFPs and PTPs did not significantly affect umbo velocity and hearing function. Large PFPs increased umbo velocity loss at low frequency (1.5 kHz) and elevated ABR thresholds within 1-2 kHz. Large PTP caused significant velocity loss at low frequencies from 1.5 to 3.5 kHz and threshold elevations at full frequencies (1-2 kHz). Two weeks after the perforation, the hearing function of rats with healed PFPs recovered completely. However, high-frequency hearing loss (16-32 kHz) persisted in rats with healed PTPs. Morphological staining revealed that no increase in the thickness and obvious increase in collagen I level of regenerated par flaccida; regenerated pars tensa exhibited obvious increase in thickness and increased collagen I, while the collagen II regeneration was limited with discontinuous and disordered structure in regenerated pars tensa.

CONCLUSION

The hearing loss caused by large PFP limits at low frequencies while large PTP can lead to hearing loss at wide range frequencies. PFP and PTP have different functional outcomes after spontaneous healing, which is determined by the discrepant structure reconstruction and collagen regeneration.

Silver Nanoparticles as an Effective Antimicrobial against Otitis Media Pathogens

Otitis Media (OM) is the most common reason for U.S. children to receive prescribed oral antibiotics, leading to potential to cause antibiotic resistance. To minimize oral antibiotic usage, we developed polyvinylpyrrolidone-coated silver nanoparticles (AgNPs-PVP), which completely eradicated common OM pathogens, i.e., Streptococcus pneumoniae and non-typeable Haemophilus influenzae (NTHi) at 1.04μg/mL and 2.13μg/mL. The greater antimicrobial efficacy against S. pneumoniae was a result of the H2O2-producing ability of S. pneumoniae and the known synergistic interactions between H2O2 and AgNPs. To enable the sustained local delivery of AgNPs-PVP (e.g., via injection through perforated tympanic membranes), a hydrogel formulation of 18%(w/v)P407 was developed. Reverse thermal gelation of the AgNPs-PVP-P407 hydrogel could gel rapidly upon entering the warm auditory bullae and thereby sustained release of antimicrobials. This hydrogel-based local delivery system completely eradicated OM pathogens in vitro without cytotoxicity, and thus represents a promising strategy for treating bacterial OM without relying on conventional antibiotics.

Immediate oral versus immediate topical versus delayed oral antibiotics for children with acute otitis media with discharge: the REST three-arm non-inferiority electronic platform-supported RCT

BACKGROUND

Acute otitis media is a painful infection of the middle ear that is commonly seen in children. In some children, the eardrum spontaneously bursts, discharging visible pus (otorrhoea) into the outer ear.

OBJECTIVE

To compare the clinical effectiveness of immediate topical antibiotics or delayed oral antibiotics with the clinical effectiveness of immediate oral antibiotics in reducing symptom duration in children presenting to primary care with acute otitis media with discharge and the economic impact of the alternative strategies.

DESIGN

This was a pragmatic, three-arm, individually randomised (stratified by age < 2 vs. ≥ 2 years), non-inferiority, open-label trial, with economic and qualitative evaluations, supported by a health-record-integrated electronic trial platform [TRANSFoRm (Translational Research and Patient Safety in Europe)] with an internal pilot.

SETTING

A total of 44 English general practices.

PARTICIPANTS

Children aged ≥ 12 months and < 16 years whose parents (or carers) were seeking medical care for unilateral otorrhoea (ear discharge) following recent-onset (≤ 7 days) acute otitis media.

INTERVENTIONS

(1) Immediate ciprofloxacin (0.3%) solution, four drops given three times daily for 7 days, or (2) delayed 'dose-by-age' amoxicillin suspension given three times daily (clarithromycin twice daily if the child was penicillin allergic) for 7 days, with structured delaying advice. All parents were given standardised information regarding symptom management (paracetamol/ibuprofen/fluids) and advice to complete the course.

COMPARATOR

Immediate 'dose-by-age' oral amoxicillin given three times daily (or clarithromycin given twice daily) for 7 days. Parents received standardised symptom management advice along with advice to complete the course.

MAIN OUTCOME MEASURE

Time from randomisation to the first day on which all symptoms (pain, fever, being unwell, sleep disturbance, otorrhoea and episodes of distress/crying) were rated 'no' or 'very slight' problem (without need for analgesia).

METHODS

Participants were recruited from routine primary care appointments. The planned sample size was 399 children. Follow-up used parent-completed validated symptom diaries.

RESULTS

Delays in software deployment and configuration led to small recruitment numbers and trial closure at the end of the internal pilot. Twenty-two children (median age 5 years; 62% boys) were randomised: five, seven and 10 to immediate oral, delayed oral and immediate topical antibiotics, respectively. All children received prescriptions as randomised. Seven (32%) children fully adhered to the treatment as allocated. Symptom duration data were available for 17 (77%) children. The median (interquartile range) number of days until symptom resolution in the immediate oral, delayed oral and immediate topical antibiotic arms was 6 (4-9), 4 (3-7) and 4 (3-6), respectively. Comparative analyses were not conducted because of small numbers. There were no serious adverse events and six reports of new or worsening symptoms. Qualitative clinician interviews showed that the trial question was important. When the platform functioned as intended, it was liked. However, staff reported malfunctioning software for long periods, resulting in missed recruitment opportunities. Troubleshooting the software placed significant burdens on staff.

LIMITATIONS

The over-riding weakness was the failure to recruit enough children.

CONCLUSIONS

We were unable to answer the main research question because of a failure to reach the required sample size. Our experience of running an electronic platform-supported trial in primary care has highlighted challenges from which we have drawn recommendations for the National Institute for Health Research (NIHR) and the research community. These should be considered before such a platform is used again.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN12873692 and EudraCT 2017-003635-10.

FUNDING

This project was funded by the NIHR Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 25, No. 67. See the NIHR Journals Library website for further project information.

Haemophilus influenzae Prevalence, Proportion of Capsulated Strains and Antibiotic Susceptibility During Colonization and Acute Otitis Media in Children, 2019-2020

BACKGROUND

The objective of this study was to determine the prevalence, proportion of encapsulated strains and antibiotic susceptibility of Haemophilus influenzae isolated from young children.

METHODS

Children, 6 months to 30 months old, were prospectively enrolled from September 2019 to September 2020 at Rochester, NY, pediatric clinics. H. influenzae isolates from nasopharynx (NP) at healthy visits and disease isolates from NP and middle ear fluid (MEF) at onset of acute otitis media (AOM) were characterized by capsular typing, β-lactamase production and antibiotic susceptibility.

RESULTS

Samples from 565 healthy visits and 130 AOM visits were collected. H. influenzae was detected 5.9% and 27% in the NP from healthy and AOM visits, respectively. In the MEF, H. influenzae was isolated in 43% of samples. Eight percent of H. influenzae isolates were encapsulated, 88% type f. Overall 39.7% of isolates were β-lactamase producing; 43% for MEF isolates. Ampicillin, trimethoprim/sulfamethoxazole, erythromycin and clarithromycin nonsusceptibility were found in more than 25% of isolates. None of the encapsulated H. influenzae isolates were positive for β-lactamase production or ampicillin nonsusceptibility. 9.2% of isolates were β-lactamase negative, ampicillin resistant (β-lactamase negative, ampicillin resistant + β-lactamase negative, ampicillin intermediate).

CONCLUSIONS

The prevalence of H. influenzae in the NP of young children is very low at times of health, but H. influenzae is highly prevalent in MEF at onset of AOM. Nontypeable H. influenzae accounts for >90% of all H. influenzae isolates. Type f predominated among encapsulated strains. β-lactamase production and antibiotic nonsusceptibility among H. influenzae strains isolated from the NP and MEF are common.

Dynamic changes in otopathogens colonizing the nasopharynx and causing acute otitis media in children after 13-valent (PCV13) pneumococcal conjugate vaccination during 2015-2019

The otopathogens colonizing the nasopharynx (NP) and causing acute otitis media (AOM) have shown dynamic changes following introduction of pneumococcal conjugate vaccines. Five hundred eighty-nine children were prospectively enrolled, 2015-2019. Two thousand fifty-nine visits (1528 healthy, 393 AOM, and 138 AOM follow-up) were studied. Two thousand forty-two NP and 495 middle ear fluid (MEF) samples by tympanocentesis from 319 AOM cases were cultured for bacterial identification and antibiotic susceptibility. Streptococcus pneumoniae (Spn) isolates were serotyped by Quellung, and multi-locus sequence type (ST) determined by genomic analysis. Haemophilus influenzae (Hi) was the most common otopathogen cultured from MEF during AOM (34% in MEF) followed by Spn (24% in MEF), then Moraxella catarrhalis (Mcat) (15% in MEF). NP isolates during healthy visit were Mcat (39%), Spn (32%), Hi (12%). 48.6% of Hi isolates from MEF were beta-lactamase-producing. Spn non-susceptibility to penicillin and other antibiotics was high. The most common Spn serotypes associated with AOM (and colonizing the NP during healthy visits) were 35B, 23B, and 15B/C. ST558 and ST199 were the most common sequence types. During 2015-2019, Hi was the most common otopathogen cultured from MEF during AOM among young children. Pneumococcal AOM was most commonly caused by non-PCV13 serotypes of Spn, predominantly 35B, 23B, and 15B/C. Resistance to common antibiotics among Spn strains showed an increasing trend.

Bacterial Spectrum of Spontaneously Ruptured Otitis Media in a 7-Year, Longitudinal, Multicenter, Epidemiological Cross-Sectional Study in Germany

We analyzed middle ear fluid (MEF) and nasopharyngeal swabs (NPS) from spontaneously ruptured acute otitis media (AOM) cases occurring in children under 5 years in Germany. The aim of the study was the assessment of disease burden and bacterial etiology in the era of routine pneumococcal vaccination. Furthermore, we aimed to compare isolates from MEF with isolates from NPS and to analyze the Streptococcus pneumoniae serotype distribution. We analyzed MEF and NPS samples in children 2 months to 5 years for vaccination status, frequency of bacterial strains, serotype/emm-type distribution of S. pneumoniae, Haemophilus influenzae, and Streptococcus pyogenes; and intraindividual correlation between MEF and NPS. From 2008 to 2014, MEF samples were collected from 2,138 subjects of which 2,001 (93.6%) also provided an NPS sample. In 851 of 2,138 MEF samples (39.8%), we identified organisms with confirmed pathogenic potential—S. pyogenes: 315 (14.7%), S. pneumoniae: 170 (8.0%), Staphylococcus aureus: 168 (7.9%), H. influenzae: 133 (6.2%), and Moraxella catarrhalis. Among NPS samples, 1,018 (50.9%) contained S. pneumoniae, 775 (38.7%) H. influenzae, 648 (32.4%) M. catarrhalis, and 344 (17.2%) S. pyogenes. Over the seven study years, the number of AOM patients steadily decreased, while the recruiting base remained constant. S. pneumoniae MEF isolates decreased by 86%, with serotype 3 being the most prevalent (25.7–42.9%). PCV13-non-PCV7-non-3 serotypes reduced to 0%. Among NPS, PCV7 serotypes decreased from 14.1 to 3.7%, PCV10: 17.6 to 3.7%, and PCV13: 55.3 to 25.7%. PCV13-non-PCV7-non-3 serotypes increased in the first 3 years of the study (17.1–22.9%), then decreased to 4.6% in year 7. Non-typeable H. influenzae reduced from 87.1 to 41.7% in MEF and from 91.4 to 54.2% in NPS. MEF and NPS isolates from the same subject were identical for 91.9% of S. pneumoniae, 99.0% of S. pyogenes, and 83.3% of H. influenzae. Among PCV7-vaccinated children, 5.6% had a PCV7 vaccine type in the MEF sample, and among PCV13-vaccinated children, 51.7% had a PCV13 serotype. Among non-vaccinated children, the percentages were 14.8 and 70.4. Pneumococcal conjugate vaccination has impacted the prevalence and etiology of spontaneously ruptured otitis media among children in Germany. Overall case numbers and pneumococcal vaccine type cases have strongly decreased.

Nasopharyngeal Microbiota Analysis in Healthy and Otitis-prone Children: Focus on History of Spontaneous Tympanic Membrane Perforation

BACKGROUND

Recurrent acute otitis media (RAOM) is common in children, and it may result in spontaneous tympanic membrane perforation (STMP), management of which is often challenging. In the upper respiratory tract (URT), resident microorganisms play a pivotal role in otitis media pathogenesis and prevention, as they are able to inhibit the colonization process and otopathogens growth. In particular, Dolosigranulum spp. and Corynebacterium spp. have been associated with respiratory health in several studies. This study aims at comparing both nasopharyngeal microbiota of children with RAOM versus matched controls and nasopharyngeal microbiota of children with a history of RAOM with STMP.

METHOD

Nasopharyngeal swabs were collected from 132 children, median age 3.51 (2.13-4.72), including 36 healthy children, 50 with RAOM without STMP, and 46 with RAOM with STMP. Bacterial DNA was subsequently extracted and 16S rRNA gene V3-V4 regions were polymerase chain reaction amplified and sequenced using Illumina MiSeq technology.

RESULTS

A higher relative abundance of Dolosigranulum and Corynebacterium genera was detected in the nasopharynx of healthy children (16.5% and 9.3%, respectively) in comparison with RAOM without STMP (8.9% and 4.3%, respectively) and RAOM with STMP (5.2% and 2.8%, respectively). A decreasing pattern in relative abundance of these 2 pivotal genera through disease severity was detected. In all groups, the most abundant genera were Moraxella, Streptococcus and Haemophilus, followed by Dolosigranulum and Corynebacterium.

CONCLUSIONS

Our study provides a characterization of the URT microbiota in otitis-prone children with and without history of recurrent STMP, suggesting that the role of Dolosigranulum and Corynebacterium in regulating the healthy URT microbiota should be further studied.

Impact and Sustainability of Antibiotic Stewardship in Pediatric Emergency Departments: Why Persistence Is the Key to Success

Antibiotic stewardship programs proved to be effective in improving prescribing appropriateness. This multicenter quasi-experimental study, aimed to assesses the stewardship impact on antibiotics prescribing in different semesters from 2014 to 2019 in three pediatric emergency departments (Center A, B, and C) in Italy. All consecutive patients diagnosed with acute otitis media or pharyngitis were evaluated for inclusion. Two different stewardship were adopted: for Center A and B, clinical pathways were implemented and disseminated, and yearly lectures were held, for Center C, only pathways were implemented. Broad-spectrum prescription rates decreased significantly by 80% for pharyngitis and 29.5 to 55.2% for otitis after the implementation. In Center C, rates gradually increased from the year after the implementation. Amoxicillin dosage adjusted to pharyngitis recommendations in Center C (53.7 vs. 51.6 mg/kg/die; p = 0.011) and otitis recommendations in Center A increasing from 50.0 to 75.0 mg/kg/die (p < 0.001). Days of therapy in children < 24 months with otitis increased from 8.0 to 10.0 in Center A, while in older children decreased in Center A (8.0 vs. 7.0; p < 0.001) and Center B (10.0 vs. 8.0; p < 0.001). Clinical pathways combined with educational lectures is a feasible and sustainable program in reducing broad-spectrum antibiotic prescribing with stable rates over time.

Respiratory Syncytial Virus-associated Acute Otitis Media in Infants and Children

Despite recent declines in the incidence of acute otitis media (AOM), more than 5 million cases and 5-6 million primary AOM visits still occur in young children in the United States, resulting in $4.4 billion direct medical costs annually. Our aims in this review are to describe the role of respiratory syncytial virus (RSV) in the etiology of AOM, discuss the prospect of prevention of RSV-associated AOM through immunization, and suggest future research strategies to assess the impact of immunization on RSV-associated AOM.

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.

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.

Updated Guidelines for the Management of Acute Otitis Media in Children by the Italian Society of Pediatrics: Treatment

BACKGROUND

New insights into the diagnosis, treatment and prevention of acute otitis media (AOM) have been gained in recent years. For this reason, the Italian Paediatric Society has updated its 2010 guidelines.

METHODS

A literature search was carried out on PubMed. Only pediatric studies published between January 1, 2010 and December 31, 2018 in English or Italian were included. Each included study was assessed according to the GRADE methodology. The quality of the systematic reviews was assessed using AMSTAR 2. The recommendations were formulated by a multidisciplinary panel of experts.

RESULTS

Prompt antibiotic treatment is recommended for children with otorrhea, intracranial complications and/or a history of recurrence and for children under the age of 6 months. For children 6 months to 2 years of age, prompt antibiotic treatment is recommended for all forms of unilateral and bilateral AOM, whether mild or severe. Prompt antibiotic treatment is also recommended for children over 2 years with severe bilateral AOM. A watchful-waiting approach can be applied to children over 2 years with mild or severe unilateral AOM or mild bilateral AOM. High doses of amoxicillin, or amoxicillin-clavulanic acid for patients with a high risk of infection by Beta-lactamase producing strains, remain the first-line antibiotics.

CONCLUSIONS

AOM should be managed on a case-by-case basis that takes account of the child's age, the severity of the episode and whether it is unilateral or bilateral. In patients under 2 years, prompt antibiotic treatment is always recommended.

In Vitro Investigation of the Antibacterial Activity of Nigella sativa Oil on Some of the Most Commonly Isolated Bacteria in Otitis Media and Externa

Objective

This study aimed to evaluate the antibacterial efficacy of Nigella sativa (NS) seed oil against the most frequently isolated infectious bacteria of the middle and external ear.

Materials and Methods

The in vitro antibacterial activity of NS oil was evaluated against 34 clinical isolates of Streptococcus pneumoniae, 32 clinical isolates of Moraxella catarrhalis, 32 clinical isolates of Haemophilus influenzae, and 32 clinical isolates of Pseudomonas aeruginosa. Staphylococcus aureus, Escherichia coli, and P. aeruginosa were also evaluated for their sensitivity to the NS oil. The minimum inhibitory concentration (MIC) of the NS oil was determined via a broth dilution technique. Serial solutions were prepared in a Mueller Hinton-F broth to achieve an ultimate concentration of NS oil within the microplate wells ranging from 256 μg/mL to 0.25 μg/mL. The growth control wells and medium were used for each bacterial strain, and the microplates were incubated at 35°C for 24 h. Those wells having no visible growth and the lowest concentration of NS oil were accepted as showing the MIC.

Results

In this study, a comparison was made between NS oil and the various antibiotics known to be effective against the bacterial strains mentioned above. The NS was shown to have bactericidal activity against H. influenzae, M. catarrhalis, and S. pneumoniae. However, the NS was not found to be effective against P. aeruginosa at any concentration.

Conclusion

The results of this laboratory-based study support the use of NS oil as an alternative treatment for ear infections. However, it is necessary to conduct clinical studies to evaluate the antibacterial efficacy of NS oil on patients with ear infections.

Acute Mastoiditis Associated with Pseudomonas Aeruginosa in the Pediatric Population of the Umbria Region, Italy

Acute mastoiditis (AM) is the most common complication of acute otitis media (AOM) and is one of the most severe acute bacterial diseases in infants and children. In some geographic areas, the incidence of AM is increasing, and the causative role of some bacterial pathogens could be greater than previously thought. In this paper, the results of a study that evaluated the epidemiology and microbial etiology of paediatric AM in Umbria, which is a region of central Italy, are reported. This is a retrospective study of patients aged 0-14 years with AM admitted to the pediatric wards of the hospitals of Umbria, Italy, between June 1 and September 30 in four consecutive years (2015-2018). A total of 108 children were enrolled. The prevalence of AM in males during the four years of analysis was significantly higher than that in females at 63% (95% confidence intervals [CI]: 0.54-0.72). The most frequently affected age groups were 5-9 years (45.4%) and 10-14 years (31.5%), with statistically significant differences in comparison with children aged <1 year (5.6%, 95% CI: 0.01-0.10) and 1-4 years (17.6%, 95% CI: 0.10-0.25). In most cases (64, 59.3%), AM was associated with spontaneous tympanic membrane perforation (STP). The culture of the middle ear fluid revealed the presence of Pseudomonas aeruginosa in 56 cases (51.6%). The mean incidence rates of pediatric AM in Umbria during the study increased significantly with time, as it was 18.18/100,000 children/year in 2015-2016 and 29.24/100,000 children/year in 2017-2018 (CI difference: +2.5 - +19.9, p < 0.05). The incidence rates of Pseudomonas aeruginosa detection in pediatric AM associated with STP significantly increased with time. The incidence was 6.06/100,000 children/year in 2015-2016 and 18.61/100,000 children/year in 2017-2018 (CI difference: +6.1 - +19.0, p < 0.001). This study demonstrated the high and increasing incidence of AM in the Umbria region during the summer months and the frequent detection of P. aeruginosa as an etiologic agent of the disease in the presence of STP. Confirmation of these results with a larger study population, in different settings, and throughout the whole year is needed to define the first-line approach of AM with STP in pediatrics.

Genetic characteristics and antibiotic resistance of Haemophilus influenzae isolates from pediatric patients with acute otitis media after introduction of 13-valent pneumococcal conjugate vaccine in Japan

Acute otitis media (AOM) occurs commonly in pediatric populations. We examined resistance genotype, antibiotic susceptibility, quinolone (QL) resistance, and multilocus sequence type (MLST) among Haemophilus influenzae isolates causing AOM following introduction of pneumococcal conjugate vaccines in Japan. The AOM surveillance group included 69 participating otolaryngologists. Causative pathogens isolated from middle ear fluid (MEF) samples collected from 582 children with AOM were identified using both bacterial culture and real-time PCR. H. influenzae isolates among these pathogens were characterized by capsular type, resistance genotype, antibiotic susceptibility, QL resistance, and MLST. In 2016, H. influenzae was identified in 319 samples (54.8%), among which 72.4% (n = 231) tested positive by both culture and PCR; remaining H. influenzae cases were only PCR-positive. This proportion of H. influenzae positivity has increased significantly from 41.2% in 2006 (p < 0.001). Among culture-positive strains, genotypic β-lactamase-nonproducing ampicillin (AMP)-resistant (gBLNAR) strains were frequent (63.2%), with β-lactamase-nonproducing AMP-susceptible (gBLNAS) strains accounting for only 24.2%. Susceptibilities of gBLNAR to oral antimicrobials were best for tosufloxacin, followed by cefditoren and tebipenem; MIC₉₀s were 0.031 μg/mL, 0.5 μg/mL, and 1 μg/mL, respectively. In 7 gBLNAR isolates (3.0%), QL susceptibility was low, owing to amino acid substitutions in GyrA and/or ParC. Sequence types identified numbered 107, including 28 that were new. Prevention of further increases in resistance to antimicrobial agents will require antibiotic selection based on characterization of causative pathogens in clinical practice.

Bacterial causes of otitis media with spontaneous perforation of the tympanic membrane in the era of 13 valent pneumococcal conjugate vaccine

After pneumococcal conjugate vaccine (PCV) implementation, the number of acute otitis media (AOM) episodes has decreased, but AOM still remains among the most common diagnoses in childhood. From 2% to 17% of cases of AOM feature spontaneous perforation of the tympanic membrane (SPTM). The aim of this study was to describe the bacteriological causes of SPTM 5 to 8 years years after PCV13 implementation, in 2010. From 2015 to 2018, children with SPTM were prospectively enrolled by 41 pediatricians. Middle ear fluid was obtained by sampling spontaneous discharge. Among the 470 children with SPTM (median age 20.8 months), no otopathogen was isolated for 251 (53.4% [95% CI 48.8%;58.0%]): 47.1% of infants and toddlers, 68.3% older children (p<0.001). Among children with isolated bacterial otopathogens (n = 219), non-typable Haemophilus influenzae (NTHi) was the most frequent otopathogen isolated (n = 106, 48.4% [95% CI 41.6%;55.2%]), followed by Streptoccocus pyogenes (group A streptococcus [GAS]) (n = 76, 34.7% [95% CI 28.4%;41.4%]) and Streptococcus pneumoniae (Sp) (n = 61, 27.9% [95% Ci 22.0%;34.3%]). NTHi was frequently isolated in infants and toddlers (53.1%), whereas the main otopathogen in older children was GAS (52.3%). In cases of co-infection with at least two otopathogens (16.9%, n = 37/219), NTHi was frequently involved (78.4%, n = 29/37). When Sp was isolated, PCV13 serotypes accounted for 32.1% of cases, with serotype 3 the main serotype (16.1%). Among Sp strains, 29.5% were penicillin-intermediate and among NTHi strains, 16.0% were β-lactamase-producers. More than 5 years after PCV13 implementation, the leading bacterial species recovered from AOM with SPTM was NTHi for infants and toddlers and GAS for older children. In both age groups, Sp was the third most frequent pathogen and vaccine serotypes still played an important role. No resistant Sp strains were isolated, and the frequency of β-lactamase-producing NTHi did not exceed 16%.

Antibodies against the Majority Subunit (PilA) of the Type IV Pilus of Nontypeable Haemophilus influenzae Disperse Moraxella catarrhalis from a Dual-Species Biofilm

Middle ear infections (or otitis media [OM]) are highly prevalent among children worldwide and present a tremendous socioeconomic challenge for health care systems. More importantly, this disease diminishes the quality of life of young children. OM is often chronic and recurrent, due to the presence of highly antibiotic-resistant communities of bacteria (called biofilms) that persist within the middle ear space. To combat these recalcitrant infections, new and powerful biofilm-directed approaches are needed. Here, we describe the ability to disrupt a biofilm formed by the two most common bacteria that cause chronic and recurrent OM in children, via an approach that combines the power of vaccines with that of traditional antibiotics. An outcome of this strategy is that antibiotics can more easily kill the bacteria that our vaccine-induced antibodies have released from the biofilm. We believe that this approach holds great promise for both the prevention and treatment of OM.

Otitis media (OM) is often polymicrobial, with nontypeable Haemophilus influenzae (NTHI) and Moraxella catarrhalis (Mcat) frequently cocultured from clinical specimens. Bacterial biofilms in the middle ear contribute to the chronicity and recurrence of OM; therefore, strategies to disrupt biofilms are needed. We have focused our vaccine development efforts on the majority subunit of NTHI type IV pili, PilA. Antibodies against a recombinant, soluble form of PilA (rsPilA) both disrupt and prevent the formation of NTHI biofilms in vitro. Moreover, immunization with rsPilA prevents and resolves NTHI-induced experimental OM. Here, we show that antibodies against rsPilA also prevent and disrupt polymicrobial biofilms. Dual-species biofilms formed by NTHI and Mcat at temperatures that mimic the human nasopharynx (34°C) or middle ear (37°C) were exposed to antiserum against either rsPilA or the OMP P5 adhesin of NTHI. NTHI+Mcat biofilm formation was significantly inhibited by antiserum directed against both adhesin proteins at either temperature. However, only anti-rsPilA disrupted NTHI+Mcat preestablished biofilms at either temperature and actively dispersed both NTHI and Mcat via interspecies quorum signaling. Newly released NTHI and Mcat were significantly more susceptible to killing by antibiotics. Taken together, these results revealed new opportunities for treatment of biofilm-associated diseases via a strategy that combines vaccine-induced antibody-mediated biofilm dispersal with traditional antibiotics, at a significantly reduced dosage to exploit the newly released, antibiotic-sensitive phenotype. Combined, our data strongly support the utility of rsPilA both as a preventative and as a therapeutic vaccine antigen for polymicrobial OM due to NTHI and Mcat.

Antibiotic Resistance of Potential Otopathogens Isolated From Nasopharyngeal Flora of Children With Acute Otitis Media Before, During and After Pneumococcal Conjugate Vaccines Implementation

BACKGROUND

To re-evaluate antibiotic strategies for acute otitis media (AOM) in young children, we analyzed the trends of nasopharyngeal carriage and antibiotic resistance of Streptococcus pneumoniae (Sp), Haemophilus influenzae (Hi) and Moraxella catarrhalis (Mc) isolated from young children with AOM during a 16-year period.

METHODS

This cross-sectional study analyzed from 2001 to 2016 the nasopharyngeal carriage of Sp, Hi and Mc of young children with AOM. Medical history and physical findings were reported. Periods were defined by pneumococcal conjugate vaccine (PCV) introduction. We separately analyzed the 13-valent PCV (PCV13) period, which started after 2013.

RESULTS

During the study, 12,973 children with AOM were enrolled by 138 pediatricians. By comparing the first and last PCV periods, the proportion of children in day care centers and that of AOM with conjunctivitis significantly increased. The proportion of penicillin nonsusceptible Sp carriage significantly decreased during the study, with 0.8% of penicillin-resistant strains isolated in the PCV13 period, but that of β-lactamase-producing Hi continually increased to 23.6% in 2016. The level of Mc β-lactamase-producing strains remained high (>97%). In the PCV13 period, the main predictors of β-lactamase-producing Hi carriage were conjunctivitis (adjusted odds ratio = 6.0, 95% confidence interval [4.7-7.7]) and attending a day care center (2.4 [1.7-3.5]).

CONCLUSIONS

In the PCV13 period, the proportion of penicillin-resistant Sp carriage was very low and that of β-lactamase-producing Hi carriage did not exceed 20% among children with AOM and without conjunctivitis. Our results suggest that amoxicillin may remain the first-line antibiotic treatment for AOM in young children except for those with conjunctivitis, for which amoxicillin-clavulanate is still the best antibiotic.

Otitis Media in Fully Vaccinated Preschool Children in the Pneumococcal Conjugate Vaccine Era

Objectives. To evaluate the effect of pneumococcal conjugate vaccine (PCV13) on the burden of acute otitis media (AOM) and to evaluate the characteristics of AOM versus otitis media with effusion (OME) in the 2 PCV periods. Methods. A cohort of fully vaccinated children aged 18 to 60 months diagnosed with AOM from 2006 to 2015 was identified. Patients with otorrhea/bulging tympanic membrane were considered as true AOM, while those without bulging/otorrhea were considered to have OME. Burden of true AOM in the PCV7 and PCV13 periods and clinical features of true AOM versus OME were compared. Results. Of 393 episodes in our cohort, 50.8% occurred in PCV7 period. Burden of true AOM in the 2 PCV groups was similar: 26% in PCV7 versus 26.4% in PCV13 (odds ratio [OR] = 1.02, 95% confidence interval [CI] = 0.65-1.60). Factors significantly associated with OME were cold season (OR = 1.54, 95% CI = 1.04-2.4), fever (OR = 2.05, 95% CI = 1.29-3.3), and recurrence (OR = 2.24, 95% CI = 1.22-4.09). No complications of AOM were identified. Majority episodes were treated with antibiotics. Conclusion. Unlike the role of PCV13 in reducing invasive pneumococcal disease, its effect on reducing the burden of AOM is minimal as compared with PCV7. With regard to characteristics of AOM versus OME, findings of tympanic membrane should be used to suggest a diagnosis of AOM, instead of occurrence of fever or recurrence of AOM episodes. Using this approach would help in guiding the use of antibiotics appropriately.

A Moraxella catarrhalis vaccine to protect against otitis media and exacerbations of COPD: An update on current progress and challenges

Moraxella catarrhalis is a major cause of morbidity and mortality worldwide, especially causing otitis media in young children and exacerbations of chronic obstructive pulmonary disease in adults. This pathogen uses several virulence mechanisms to colonize and survive in its host, including adherence and invasion of host cells, formation of polymicrobial biofilms with other bacterial pathogens, and production of β-lactamase. Given the global impact of otitis media and COPD, an effective vaccine to prevent M. catarrhalis infection would have a huge impact on the quality of life in both patient populations by preventing disease, thus reducing morbidity and health care costs. A number of promising vaccine antigens have been identified for M. catarrhalis. The development of improved animal models of M. catarrhalis disease and identification of a correlate of protection are needed to accelerate vaccine development. This review will discuss the current state of M. catarrhalis vaccine development, and the challenges that must be addressed to succeed.