The role of anaerobic bacteria in chronic suppurative otitis media in children: implications for medical therapy

Recurrent pyogenic brain abscess in immunocompetent patient by Bacteroides fragilis: A silent cause of concern

Anaerobic bacteria are rare but important cause of otogenic brain abscess. Improved patient management techniques and early clinical and laboratory diagnosis of otogenic infections are necessary to reduce the risk of intracranial complications. Here we present a case of recurrent pyogenic brain abscess caused by Bacteroides fragilis secondary to otitis media.

Integrated Health Solutions: Addressing the Co-occurrence of Otitis Media With Effusion and Early Childhood Caries in Preschool Children

Introduction: Otitis media with effusion (OME) is a common middle ear condition, which frequently affects children and can lead to hearing impairment, speech delays, and developmental issues. Early childhood caries (ECC) is another prevalent pediatric condition defined by the presence of decayed, missing, or filled tooth surfaces in children under six years old. Objectives: This study aims to determine the prevalence of OME and ECC, the association between these two conditions, and the risk and severity of ECC among preschool children with OME. Methodology: A prospective cross-sectional study was conducted at a single tertiary center. A total of 206 preschool children aged six and below with hearing impairment or speech delay were recruited. They were grouped as follows: with OME (n = 129) and without OME (n = 77). Demographic and socioeconomic data were obtained, followed by otoscopy, anterior rhinoscopy, and tympanometric assessment. The subjects were further stratified into having ECC or not by conducting a dental examination for caries detection, whose findings were documented using Dental Charting and Caries Risk Assessment (CRA). Tympanometric width (TW) was also analyzed to measure its association with tympanic membrane appearance. Results: 51.5% (n=106) of children with OME were found to have ECC. They predominantly had mild ECC (49.1%), and most (51%) were at moderate risk for caries based on the CRA (P < 0.001). A significant association between OME and ECC was observed (p < 0.001). Tympanometry results documented a strong correlation between TW greater than 200 daPa and abnormal tympanic membrane findings in OME (P < 0.001). Conclusions: The association between OME and ECC in preschool children necessitates integrated healthcare approaches for early detection and management. Reliable diagnostic tools, such as tympanic width measurement for OME and CRA for ECC, are crucial in addressing these health issues. Early intervention and comprehensive care can mitigate the risks and improve health outcomes for affected children.

Otogenic Cerebellar Abscess with Polymicrobial Anaerobic Infection in a Young Female- A Rare Presentation

Brain abscess is a serious clinical condition caused by a localized collection of pus within the brain tissue. This typically occurs as a result of an infection that originates from a nearby area, such as an ear, sinus, or dental infection, or an infection in the bloodstream. Streptococcus and Staphylococcus species are the most common organisms implicated in brain abscesses. Apart from aerobic growth, cases of mixed infections of both aerobic and anaerobic organisms are also commonly reported in the literature. Herein we report a 23-year-old immunocompetent female with chronic otitis media who presented with cerebellar abscess where the aerobic growth was sterile and anaerobic culture revealed pure growth of dual anaerobes viz… Peptostreptococcus and Bacteroides thetaiotaomicron. This case highlights the importance of prompt diagnosis and management of polymicrobial anaerobic infection in cases of brain abscess.

Genomic and metabolic versatility of Pseudomonas aeruginosa contributes to its inter-kingdom transmission and survival

Pseudomonas aeruginosa is one of the most versatile bacteria with renowned pathogenicity and extensive drug resistance. The diverse habitats of this bacterium include fresh, saline and drainage waters, soil, moist surfaces, taps, showerheads, pipelines, medical implants, nematodes, insects, plants, animals, birds and humans. The arsenal of virulence factors produced by P. aeruginosa includes pyocyanin, rhamnolipids, siderophores, lytic enzymes, toxins and polysaccharides. All these virulent elements coupled with intrinsic, adaptive and acquired antibiotic resistance facilitate persistent colonization and lethal infections in different hosts. To date, treating pulmonary diseases remains complicated due to the chronic secondary infections triggered by hospital-acquired P. aeruginosa. On the contrary, this bacterium can improve plant growth by suppressing phytopathogens and insects. Notably, P. aeruginosa is one of the very few bacteria capable of trans-kingdom transmission and infection. Transfer of P. aeruginosa strains from plant materials to hospital wards, animals to humans, and humans to their pets occurs relatively often. Recently, we have identified that plant-associated P. aeruginosa strains could be pathologically similar to clinical isolates. In this review, we have highlighted the genomic and metabolic factors that facilitate the dominance of P. aeruginosa across different biological kingdoms and the varying roles of this bacterium in plant and human health.

Otitis media: recent advances in otitis media vaccine development and model systems

Otitis media is an inflammatory disorder of the middle ear caused by airways-associated bacterial or viral infections. It is one of the most common childhood infections as globally more than 80% of children are diagnosed with acute otitis media by 3 years of age and it is a common reason for doctor's visits, antibiotics prescriptions, and surgery among children. Otitis media is a multifactorial disease with various genetic, immunologic, infectious, and environmental factors predisposing children to develop ear infections. Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis are the most common culprits responsible for acute otitis media. Despite the massive global disease burden, the pathogenesis of otitis media is still unclear and requires extensive future research. Antibiotics are the preferred treatment to cure middle ear infections, however, the antimicrobial resistance rate of common middle ear pathogens has increased considerably over the years. At present, pneumococcal and influenza vaccines are administered as a preventive measure against otitis media, nevertheless, these vaccines are only beneficial in preventing carriage and/or disease caused by vaccine serotypes. Otitis media caused by non-vaccine serotype pneumococci, non-typeable H. influenza, and M. catarrhalis remain an important healthcare burden. The development of multi-species vaccines is an arduous process but is required to reduce the global burden of this disease. Many novel vaccines against S. pneumoniae, non-typeable H. influenza, and M. catarrhalis are in preclinical trials. It is anticipated that these vaccines will lower the disease burden and provide better protection against otitis media. To study disease pathology the rat, mouse, and chinchilla are commonly used to induce experimental acute otitis media to test new therapeutics, including antibiotics and vaccines. Each of these models has its advantages and disadvantages, yet there is still a need to develop an improved animal model providing a better correlated mechanistic understanding of human middle ear infections, thereby underpinning the development of more effective otitis media therapeutics. This review provides an updated summary of current vaccines against otitis media, various animal models of otitis media, their limitations, and some future insights in this field providing a springboard in the development of new animal models and novel vaccines for otitis media.

Identification of bacteria associated with canine otitis externa based on 16S rDNA high-throughput sequencing

Bacteria are regarded as predisposing and perpetuating factors causing otitis externa (OE), whereas auricular anatomy is a predisposing factor. This study aims to investigate bacterial populations in the external auditory canals of healthy dogs and dogs with OE. Four categories of ear swabs included healthy erect-ear dogs, erect-ear dogs with OE, healthy pendulous-ear dogs and pendulous-ear dogs with OE. After bacterial DNA extraction, 16S rDNAs were amplified using specific primers within a V3/V4 region. Following DNA library construction, high-throughput sequencing was performed on MiSeq (Illumina). CLC Microbial Genomics Module was used to determine the rarefaction curve, bacterial classification, relative abundance, richness and diversity index. The results demonstrated that healthy dogs had higher bacterial richness and diversity than the dogs with OE. Comparable with culture-dependent methods described previously, this study revealed predominant Corynebacterium spp., Pseudomonas spp., Staphylococcus spp., and Proteus spp. in OE cases. Furthermore, high-throughput sequencing might disclose some potential emerging pathogens including Tissierella spp., Acinetobacter spp., and Achromobacter spp., which have not been reported in previous canine OE cases. Nevertheless, larger sample sizes are further required for an extensive evidence-based investigation.

Antibiogram guided optimized medical treatment in chronic otitis media: A useful interventional strategy before surgery?

BACKGROUND

Chronic otitis media is a middle ear cleft disease presenting with tympanic membrane perforation and discharge. Wet ear after tympanoplasty and discharging mastoid cavity are problematic in clinical practice.

MATERIAL AND METHODS

1050 patients of age 10 to 50 years presenting with active ear discharge and clinically diagnosed with unilateral chronic suppurative otitis media were included in the study. The patients were equally divided into two equal groups, Group ET, and AT. All patients were prescribed topical ciprofloxacin, oral levocetirizine 5 mg and n-acetyl cysteine 600 mg BD for one week. Swabs of ear discharge were collected in ET groups for antibiogram. Both groups were evaluated on next visit and treatment changed in AT groups and result observed in next visit. Surgical outcome was evaluated at end of 2 yrs.

RESULT

A total of 1158 organisms were isolated in culture out of which, 69.94 % were aerobes, 13.47 % anaerobes and 16.58 % were fungi. On the second visit in group AT, treatment of 85.14 % patients was changed in accordance with culture sensitivity report. In patients with mucosal disease, only 46.87 % patients of group ET had a favorable outcome in comparison to 90.28 % patients of group AT while in patients with squamosal disease, 17.56 % patients of group ET and 28.99 % patients in group AT had a dry ear. Surgeries in AT group were found to have statistically significant higher success rate as compared to ET group.

Profile of aerobic bacteria and their antibiotic sensitivity in chronic suppurative otitis media in Al-Ramadi Teaching Hospital, Ramadi City, Iraq

BACKGROUND

Chronic suppurative otitis media (CSOM) is a common otological problem in daily clinical practice. It is crucial to know the bacterial pathogens and their antimicrobial susceptibilities in patients with CSOM to achieve a good clinical outcome.

OBJECTIVES

To identify the aerobic bacterial pathogens and their antibiotic sensitivities in subjects with CSOM in Al-Ramadi Teaching Hospital.

MATERIALS AND METHODS

A cross-sectional, descriptive study included 102 subjects with a clinical diagnosis of CSOM (aural discharge >2 weeks, eardrum perforation, and conductive deafness). Purulent discharge was obtained from the middle ear with sterile swabs and cultured for bacterial microorganisms. The sensitivity of the isolated agents to antimicrobials was evaluated by a culture and sensitivity method. SPSS version 22 was used for statistical analysis of the data. Differences were considered statistically significant at p < 0.05.

RESULTS

Out of 3634 outpatient subjects, 102 (2.8%) presented with active CSOM. The age range of the patients was 1-70 years (mean 28.90 ± 19.8). There were 58 females (56.9%). Out of 117 ear swab specimens, 107 (91.5%) yielded positive cultures. The majority (101, 94.4%) of the specimens yielded a single organism. There was a high statistically significant difference (p < 0.001) between gram-positive (n = 77, 68.1%) and gram-negative pathogens (n = 36, 31.9%). Pseudomonas aeruginosa in 65 (57.5%) cases and Staphylococcus aureus in 19 (16.8%) cases were the two most commonly isolated organisms. The drugs imipenem (93.8%), amikacin (86.1%), azteronam (83.1%), and ciprofloxacin (81.5%) were effective against P. aeruginosa (p < 0.001). Amikacin (100%), imipenem (94.7%), ciprofloxacin (68.4%), and gentamicin (63.1%) were the most effective antibiotics against Staph. aureus (p < 0.001).

CONCLUSION

The prevalence rate of active CSOM was 2.8%. Ciprofloxacin showed high effectiveness against the two most common isolated pathogens (P. aeruginosa and Staph. aureus); therefore, it could be used as empirical therapy for active CSOM cases.

From Evidence to Clinical Guidelines in Antibiotic Treatment in Acute Otitis Media in Children

Acute otitis media (AOM) in children represents a public health concern, being one of the leading causes of health care visits and antibiotic prescriptions worldwide. The overall aim of this paper is to unravel the major current insights into the antibiotic treatment of AOM in children. Our approach is three-fold: 1. a preclinical evaluation of antibiotics in animal models of AOM stressing on the advantages of different species when testing for different schemes of antibiotics; 2. an overview on the new antimicrobial agents whose efficacy has been demonstrated in refractory cases of AOM in children; and 3. an analysis of the different guidelines stressing on the differences and similarities between the various schemes of antibiotic treatment. The preferred therapeutic agents remain amoxicillin and the amoxicillin-clavulanate combination for AOM caused by Streptococcus pneumoniae, whereas oral cephalosporin is preferred in AOM due to Moraxella catarrhalis and Haemophilus influenzae. As for the second and third line antimicrobial treatments, there is a wide variety of suggested antibiotic classes with variations in duration and posology. The decision to prescribe antimicrobial treatment as a first-line choice is based on the severity of the symptoms in 16 of the guidelines included in this review.

Causality of Chronic Suppurative Otitis Media: An Observational Study

Objective

Chronic otorrhoea is a disease of the ear that lasts for more than 6-12 weeks, through a perforated tympanic membrane. We sought to determine the cause of chronic suppurative otitis media (CSOM) at our institute.

Methodology

Ear swabs taken from enrolled patients (n=139) were sent for culture and sensitivity. Statistical analysis was done using Statistical Package for Social Sciences (SPSS), version 26 (IBM Corp., Armonk, NY)

Results

Common pathogenic bacteria in chronic otitis media observed were Pseudomonas aeruginosa 81 (58%) while Klebsiella pneumoniae was found in 58 (42%) of cases.

Conclusion

We concluded that Pseudomonas aeruginosa was the most common causative agent of CSOM at our institute.

A child with recurrent otitis media due to Bacteroides thetaiotaomicron

Brain abscess remains a life-threatening condition. Here, we are reporting a case of brain abscess due to Bacteroides thetaiotaomicron in a previously known case of recurrent otitis media. A 15 years old boy with a history of recurrent otitis media presented with the complaints of right otalgia, headache and fever. Computed Tomography (CT) brain and neck revealed fluid filled right middle ear cavity with bony destruction along the inner cortex of right temporal bone. The abscess was drained and culture showed growth of Bacteroides thetaiotaomicron. This report illustrates the importance of MALDI-TOF MS in the species level identification of anaerobes thereby facilitating the selection of appropriate and prompt adjuvant antibiotic therapy. This timely identification thus led to a favourable outcome in an era of increasing antimicrobial resistance.

Prospective observational case series evaluating middle ear fluid and tympanostomy tubes through pyrosequencing

OBJECTIVE

One of the most common sequelae of tympanostomy tube (TT) placement is post-tympanostomy tube otorrhea (PTTO). Granulation tissue formation has been reported in 5-13.8% of patients with TT placement. The purpose of this study is to determine the biodistribution of microorganisms on TTs and middle ear fluid obtained from patients with PTTO.

METHODS

This was a prospective observational study of subjects (6-months-16-years) who underwent standard of care treatment for chronic PTTO. Data was collected on diagnosis, existence of antibiotic resistance, duration of tube placement, and evidence of recurrent infection and/or PTTO. TTs and middle ear fluid were subjected to pyrosequencing; additionally, ear fluid samples were sent for culture-based laboratory diagnostics.

RESULTS

DNA-pyrosequencing analysis of bacteria from fluid and TTs of pediatric subjects with PTTO revealed a mixture of both aerobic and anaerobic populations. Retained tubes with minimal otorrhea revealed a predominance of Staphylococcus species, normal external auditory canal (EAC) microbiome, within middle ear fluid as well as on TTs. However, TTs with active mucopurulent otorrhea and granulation tissue unveiled prominence of Gram-negative facultative anaerobes such as Pseudomonas and Eikenella. Discrepancies in prominent bacteria were seen between standard culture-based techniques versus pyrosequencing.

CONCLUSION

Retained tympanostomy tubes are colonized primarily with normal flora of the EAC. However, mucopurulent otorrhea associated with granulation tissue formation revealed a prominence of Gram-negative facultative anaerobes. Standard culture-based diagnostics may identify bacteria, which are not predominant species of infection. Future studies are necessary to assess the association of Gram-negative facultative anaerobes with granulation tissue formation.

Chronic Ear Disease

Chronic ear disease is composed of a spectrum of otologic disorders intrinsically tied to Eustachian tube dysfunction. Presentation can range from asymptomatic findings on physical examination to critically ill patients with intracranial complications. Internists represent the first line in diagnosis of these conditions, making awareness of the common signs and symptoms essential. With surgical management often required, partnership between internal medicine and otolaryngology is fundamental in the management of patients with chronic ear disease.

Microbial otitis media: recent advancements in treatment, current challenges and opportunities

Otitis media (OM) is a common disease affecting humans, especially paediatric populations. OM refers to inflammation of the middle ear and can be broadly classified into two types, acute and chronic. Bacterial infection is one of the most common causes of OM. Despite the introduction of vaccines, the incidence of OM remains significantly high worldwide. In this mini-review article, we discuss the recent treatment modalities for OM, such as suspension gel, transcutaneous immunization, and intranasal and transtympanic drug delivery, including therapies that are currently undergoing clinical trials. We provide an overview of how these recent advancements in therapeutic strategies can facilitate the circumvention of current treatment challenges involving preadolescence soft palate dysfunction, biofilm formation, tympanic membrane (ear drum) barrier and the attainment of efficacious drug concentrations in the middle ear. While traditional first-line immunization strategies are generally not very efficacious against biofilms, new technologies that use transdermal or intranasal drug delivery via chitosan-PsaA nanoparticles have shown promising results in experimental animal models of OM. Sustained drug delivery systems such as penta-block copolymer poloxamer 407-polybutylphosphoester (P407-PBP) or poloxamer 407 (e.g. OTO-201, with the brand name 'OTIPRIO') have demonstrated that treatments can be reduced to a single topical application. The emergence of effective new treatment modalities opens up promising new avenues for the treatment of OM that could lead to improved quality of life for many children and their families.

Aerobic bacteria associated with chronic suppurative otitis media in Angola

Background

Chronic suppurative otitis media (CSOM) is an important cause of hearing loss in children and constitutes a serious health problem globally with a strong association to resource-limited living conditions. Topical antibiotics combined with aural toilet is the first-hand treatment for CSOM but antimicrobial resistance and limited availability to antibiotics are obstacles in some areas. The goal of this study was to define aerobic pathogens associated with CSOM in Angola with the overall aim to provide a background for local treatment recommendations.

Methods

Samples from ear discharge and the nasopharynx were collected and cultured from 152 patients with ear discharge and perforation of the tympanic membrane. Identification of bacterial species was performed with matrix-assisted laser desorption/ionization-time of flight mass spectrometry and pneumococci were serotyped using multiplex polymerase chain reactions. Antimicrobial susceptibility testing was done according to EUCAST.

Results

One hundred eighty-four samples from ear discharge and 151 nasopharyngeal swabs were collected and yielded 534 and 289 individual isolates, respectively. In all patients, correspondence rate of isolates from 2 ears in patients with bilateral disease was 27.3% and 9.3% comparing isolates from the nasopharynx and ear discharge, respectively. Proteus spp. (14.7%), Pseudomonas aeruginosa (13.2%) and Enterococcus spp. (8.8%) were dominating pathogens isolated from ear discharge. A large part of the remaining species belonged to Enterobacteriaceae (23.5%). Pneumococci and Staphylococcus aureus were detected in approximately 10% of nasopharyngeal samples. Resistance rates to quinolones exceeded 10% among Enterobacteriaceae and was 30.8% in S. aureus, whereas 6.3% of P. aeruginosa were resistant.

Conclusions

The infection of the middle ear in CSOM is highly polymicrobial, and isolates found in nasopharynx do not correspond well with those found in ear discharge. Pathogens associated with CSOM in Angola are dominated by gram-negatives including Enterobacteriaceae and P. aeruginosa, while gram-positive enterococci also are common. Based on the results of antimicrobial susceptibility testing topical quinolones would be the preferred antibiotic therapy of CSOM in Angola. Topical antiseptics such as aluminium acetate, acetic acid or boric acid, however, may be more feasible options due to a possibly emerging antimicrobial resistance.

Electronic supplementary material

The online version of this article (10.1186/s40249-018-0422-7) contains supplementary material, which is available to authorized users.

Otogenic brain abscesses: A systematic review

Objective

Otogenic brain abscesses are one of the most significant life-threatening complications of otologic infections. Given their low prevalence, otogenic brain abscesses require a high index of suspicion for diagnosis. In this systematic review, we aim to provide an analysis of otogenic brain abscesses and describe common clinical signs and symptoms, bacteriology, location, treatment options, morbidity, and mortality.

Data Sources

PubMed, Cochrane CENTRAL database, Google Scholar, and Scopus.

Methods

A systematic review of literature was performed using the Preferred Reporting Items for Systematic Reviews and Meta-analyses recommendations. Variables assessed included clinical signs and symptoms, bacteriology, location, treatment, morbidity, and mortality.

Results

Twenty-nine studies met inclusion and exclusion criteria, corresponding to a total of 1307 otogenic abscess cases for review. Fifty-five percent of abscesses were found in the temporal lobe and 28% in the cerebellum. Most patients (88.3%) had a history of suppurative chronic otitis media. The most common symptoms were headache, altered mental status, papilledema, and meningeal irritation. Fever, nausea, and vomiting affected about 40% of patients. The most commonly cultured bacterial species was Proteus mirabilis. In addition to antibiotics, most otogenic brain abscesses were treated by burr hole aspiration. Average mortality following advent of computed tomography was 8.11%.

Conclusion

Although rare, otogenic brain abscesses may occur as a complication of suppurative otitis media and require a high index of suspicion. Appropriate imaging studies and multidisciplinary expertise are crucial in the diagnosis and management.

Level of Evidence

4.

Safety of transtympanic application of probiotics in a chinchilla animal model

Background

Chronic suppurative otitis media can be recalcitrant and difficult to treat, particularly with the increasing occurrence of antibiotic resistance. Lactobacillus plantarum is a probiotic that has been shown to decrease S. aureus and P. aeruginosa growth in wounds, making it a good candidate for the treatment of chronic suppurative otitis media. However, before it can be applied in the ear, its ototoxicity potential must be evaluated.

Methods

A prospective controlled trial was conducted in a chinchilla animal model at the Animal care research facilities of the Montreal Children’s Hospital Research Institute to determine whether Lactobacillus plantarum is ototoxic when applied transtympanically. Ten chinchillas each had one ear randomly assigned to receive 10⁹ CFU/mL of Lactobacillus plantarum solution, while the contralateral ear received saline. Auditory brainstem responses were measured bilaterally at 8, 20, 25 kHz before, at 7–10 days after application, and at 28 days after application of probiotic or saline. Facial nerve and vestibular function were assessed clinically.

Results

There were no statistically significant differences in hearing thresholds between control and experimental ears at 28 days after application. A difference of 11 dB was noted in the 25 kHz range at day 7–10, but resolved by day 28. No animals receiving probiotics developed vestibular nerve dysfunction. There was no histologic evidence of auditory hair cell damaged evidenced by scanning electron microscopy.

Conclusion

Our study suggests that a single application of Lactobacillus plantarum at 10⁹ CFU/mL does not cause ototoxicity in a chinchilla animal model. These preliminary safety evaluations and the pathogen inhibitory effects of L. plantarum demonstrated by previous studies present this probiotic as a candidate of interest for further investigation.

Electronic supplementary material

The online version of this article (10.1186/s40463-017-0242-y) contains supplementary material, which is available to authorized users.

Planktonic Growth of Pseudomonas aeruginosa around a Dual-Species Biofilm Supports the Growth of Fusobacterium nucleatum within That Biofilm

PURPOSE

The goal of this study was to understand the potential interaction between Pseudomonas aeruginosa and Fusobacterium nucleatum within the middle ear.

METHODS

We examined the microbiota of ear fluid and tympanostomy tubes (TTs) obtained from patients with posttympanostomy tube otorrhea. We also examined biofilms formed by P. aeruginosa and F. nucleatum, singly or together, under aerobic or anaerobic conditions.

RESULTS

While the facultative anaerobe P. aeruginosa dominated the bacterial population within the ear fluid, strict anaerobes, including F. nucleatum, dominated bacterial populations within the TTs. F. nucleatum was able to grow under aerobic conditions only in the presence of P. aeruginosa, whose growth reduced the level of dissolved oxygen within the broth to nearly anoxic condition within 4 h after inoculation. The presence of P. aeruginosa allowed F. nucleatum to maintain its growth for 72 h within the dual-species biofilm but not within the planktonic growth. Visualization of the biofilms revealed coaggregation of P. aeruginosa and F. nucleatum.

CONCLUSION

Extrapolation of these results suggests that, within the middle ear fluid, the growth of P. aeruginosa produces the anaerobic conditions required for the growth of F. nucleatum, both within effusion and within biofilms.

Microbiology of otitis media in Indigenous Australian children: review

Objectives:

To review research addressing the polymicrobial aetiology of otitis media in Indigenous Australian children in order to identify research gaps and inform best practice in effective prevention strategies and therapeutic interventions.

Methods:

Literature review.

Results:

Studies of aspirated middle-ear fluid represented a minor component of the literature reviewed. Most studies relied upon specimens from middle-ear discharge or the nasopharynx. Culture-based middle-ear discharge studies have found that non-typeableHaemophilus influenzaeandStreptococcus pneumoniaepredominate, withMoraxella catarrhalis, Staphylococcus aureusandStreptococcus pyogenesisolated in a lower proportion of samples.Alloiococcus otitidiswas detected in a number of studies; however, its role in otitis media pathogenesis remains controversial. Nasopharyngeal colonisation is a risk factor for otitis media in Indigenous infants, and bacterial load of otopathogens in the nasopharynx can predict the ear state of Indigenous children.

Conclusion:

Most studies have used culture-based methods and specimens from middle-ear discharge or the nasopharynx. Findings from these studies are consistent with international literature, but reliance on culture may incorrectly characterise the microbiology of this condition. Advances in genomic technologies are now providing microbiologists with the ability to analyse the entire mixed bacterial communities (‘microbiomes’) of samples obtained from Indigenous children with otitis media.

Middle ear microbiome differences in indigenous Filipinos with chronic otitis media due to a duplication in the A2ML1 gene

Background

Previously rare A2ML1 variants were identified to confer otitis media susceptibility in an indigenous Filipino community and in otitis-prone US children. The goal of this study is to describe differences in the middle ear microbiome between carriers and non-carriers of an A2ML1 duplication variant that increases risk for chronic otitis media among indigenous Filipinos with poor health care access.

Methods

Ear swabs were obtained from 16 indigenous Filipino individuals with chronic otitis media, of whom 11 carry the A2ML1 duplication variant. Ear swabs were submitted for 16S rRNA gene sequencing.

Results

Genotype-based differences in microbial richness, structure, and composition were identified, but were not statistically significant. Taxonomic analysis revealed that the relative abundance of the phyla Fusobacteria and Bacteroidetes, and genus Fusobacterium were nominally increased in carriers compared to non-carriers, but were non-significant after correction for multiple testing. We also detected rare bacteria including Oligella that was reported only once in the middle ear.

Conclusions

These findings suggest that A2ML1-related otitis media susceptibility may be mediated by changes in the middle ear microbiome. Knowledge of middle ear microbial profiles according to genetic background can be potentially useful for therapeutic and prophylactic interventions for otitis media and can guide public health interventions towards decreasing otitis media prevalence within the indigenous Filipino community.

Electronic supplementary material

The online version of this article (doi:10.1186/s40249-016-0189-7) contains supplementary material, which is available to authorized users.

Genetic and Environmental Determinants of Otitis Media in an Indigenous Filipino Population

OBJECTIVE

To identify genetic and environmental risk factors for otitis media in an indigenous Filipino population.

STUDY DESIGN

Cross-sectional study.

SETTING

Indigenous Filipino community.

SUBJECTS AND METHODS

Clinical history and information on breastfeeding, tobacco smoke exposure, and swimming were obtained from community members. Heads of households were interviewed for family history and personal beliefs on ear health. Height and weight were measured. Otoscopic findings were described for the presence and character of perforation or discharge. An A2ML1 duplication variant that confers otitis media susceptibility was Sanger sequenced in all DNA samples. Co-occurrence of middle ear bacteria detected by 16S rRNA gene sequencing was determined according to A2ML1 genotype and social cluster.

RESULTS

The indigenous Filipino population has a ~50% prevalence of otitis media. Young age was associated with otitis media (4 age strata; P = .004); however, age was nonsignificant as a bistratal or continuous variable. There was no association between otitis media and sex, body mass index, breastfeeding, tobacco exposure, or deep swimming. In multivariate analyses, A2ML1 genotype is the strongest predictor of otitis media, with an odds ratio of 3.7 (95% confidence interval: 1.3-10.8; P = .005). When otitis media diagnoses were plotted across ages, otitis media was observed within the first year of life, and chronic otitis media persisted up to adulthood, particularly in A2ML1-variant carriers.

CONCLUSION

Among indigenous Filipinos, A2ML1 genotype is the primary risk factor for otitis media and main determinant of disease progression, although age, the middle ear microbiome, and social clusters might modulate the effect of the A2ML1 genotype.

Current concepts in the pathogenesis and treatment of chronic suppurative otitis media

Otitis media (OM) is an inflammation of the middle ear associated with infection. Despite appropriate therapy, acute OM (AOM) can progress to chronic suppurative OM (CSOM) associated with ear drum perforation and purulent discharge. The effusion prevents the middle ear ossicles from properly relaying sound vibrations from the ear drum to the oval window of the inner ear, causing conductive hearing loss. In addition, the inflammatory mediators generated during CSOM can penetrate into the inner ear through the round window. This can cause the loss of hair cells in the cochlea, leading to sensorineural hearing loss. Pseudomonas aeruginosa and Staphylococcus aureus are the most predominant pathogens that cause CSOM. Although the pathogenesis of AOM is well studied, very limited research is available in relation to CSOM. With the emergence of antibiotic resistance as well as the ototoxicity of antibiotics and the potential risks of surgery, there is an urgent need to develop effective therapeutic strategies against CSOM. This warrants understanding the role of host immunity in CSOM and how the bacteria evade these potent immune responses. Understanding the molecular mechanisms leading to CSOM will help in designing novel treatment modalities against the disease and hence preventing the hearing loss.

Clinical and audiological findings in children with acute otitis media

CONCLUSION

It is recommended to perform follow-up tympanometry and if necessary tonal audiometry in children who have normal plain otoscopy findings after recovering from acute otitis media (AOM). Children with Type B tympanogram, 3 months following the onset of AOM, are very likely to have a conductive hearing loss. Type B tympanogram is a much better indicator of effusion in the middle ear compared to plain otoscopy.

OBJECTIVE

This study was undertaken to investigate the frequency and duration of middle ear effusion in children following an episode of acute otitis media, to track changes in tonal audiometry and tympanometry findings in the post-AOM period, and recognize the optimal timing for performing both tests.

METHODS

In this study, 125 children aged 5-7 years with bilateral AOM were randomly selected and separately followed up for 3 months. The children underwent six ear, nose, and throat (ENT 1-6) examinations, six tympanometries (TM 1-6), and three tonal audiometries (TA 1-3). Evaluation of nasopharynx was done at the ENT 1 examination. Children who received ventilation tubes were followed for 21 month altogether.

RESULTS

At the first otoscopy, pathological findings were recorded in 250 ears/125 children (100.0%). The number of pathological otoscopy findings decreased at each subsequent examination. At ENT 6 all children had normal otoscopy findings. Type B tympanogram was detected in 49/250 (19.6%) ears at TM 6, performed 3 months following the onset of the disease. At the TA 1 conductive hearing impairment was recorded in 158/250 (63.2%) ears, at TA 2 in 66/250 (26.4%), and at TA 3 in 39/250 (15.6%). Most of them were associated with Type B tympanogram.

Suppurative otitis and ascending meningoencephalitis associated with Bacteroides tectus and Porphyromonas gulae in a captive Parma wallaby (Macropus parma) with toxoplasmosis

A 6-year-old female Parma wallaby (Macropus parma) at a zoo in California developed acute ataxia and left-sided circling. Despite intensive care, clinical signs progressed to incoordination and prostration, and the animal was euthanized. At necropsy, the left tympanic cavity was filled with homogeneous suppurative exudate that extended into the cranium expanding the meninges and neuroparenchyma in the lateral and ventral aspect of the caudal ipsilateral brainstem and medulla oblongata. Microscopically, the brainstem showed regional severe suppurative meningoencephalitis with large numbers of neutrophils, fewer macrophages, and lymphocytes admixed with fibrin, necrotic cellular debris, hemorrhage, and mineralization, with numerous intralesional Gram-negative bacilli. Bacteroides spp. and Porphyromonas spp. were isolated on anaerobic culture from the meninges, and the bacteria were further characterized by partial 16S ribosomal RNA gene sequencing as Bacteroides tectus and Porphyromonas gulae. Bacterial aerobic culture from the meninges yielded very low numbers of mixed flora and Proteus spp., which were considered contaminants. Culture of Mycoplasma spp. from middle ear and meninges was negative. Additionally, Toxoplasma gondii cysts were detected by immunohistochemistry in the heart and brain, and anti-Toxoplasma antibodies were detected in serum. The genera Bacteroides and Porphyromonas have been associated with oral disease in marsupials; but not with otitis and meningoencephalitis. The results of the present work highlight the importance of performing anaerobic cultures in the diagnostic investigation of cases of suppurative otitis and meningoencephalitis in macropods.

Predominant pathogen competition and core microbiota divergence in chronic airway infection

Chronic bacterial lung infections associated with non-cystic fibrosis bronchiectasis represent a substantial and growing health-care burden. Where Pseudomonas aeruginosa is the numerically dominant species within these infections, prognosis is significantly worse. However, in many individuals, Haemophilus influenzae predominates, a scenario associated with less severe disease. The mechanisms that determine which pathogen is most abundant are not known. We hypothesised that the distribution of H. influenzae and P. aeruginosa would be consistent with strong interspecific competition effects. Further, we hypothesised that where P. aeruginosa is predominant, it is associated with a distinct 'accessory microbiota' that reflects a significant interaction between this pathogen and the wider bacterial community. To test these hypotheses, we analysed 16S rRNA gene pyrosequencing data generated previously from 60 adult bronchiectasis patients, whose airway microbiota was dominated by either P. aeruginosa or H. influenzae. The relative abundances of the two dominant species in their respective groups were not significantly different, and when present in the opposite pathogen group the two species were found to be in very low abundance, if at all. These findings are consistent with strong competition effects, moving towards competitive exclusion. Ordination analysis indicated that the distribution of the core microbiota associated with each pathogen, readjusted after removal of the dominant species, was significantly divergent (analysis of similarity (ANOSIM), R=0.07, P=0.019). Taken together, these findings suggest that both interspecific competition and also direct and/or indirect interactions between the predominant species and the wider bacterial community may contribute to the predominance of P. aeruginosa in a subset of bronchiectasis lung infections.

Optimising the pre-treatment process before mobile ear surgery for chronic suppurative otitis media in Wolisso and Attat, Ethiopia

Background:

Chronic suppurative otitis media is a major cause of long-standing hearing impairment in many Sub-Saharan African countries.

Methods:

Attempts were made to optimise the pre-treatment process before mobile ear surgery for chronic suppurative otitis media in Wolisso, a semi-urban community in the Oromia region, and in Attat, a rural community in the Gurage region, both in the south-west of Ethiopia, between 2008 and 2010. This included special training for ENT nurses, and the use of a strict scheduling regime and improved topical treatment.

Results and conclusion:

This strategy allowed effective middle-ear surgery to be carried out using simple means and with a mobile ear surgery team, the latter of which is only transiently but regularly on site.

Bacteriology of chronic suppurative otitis media (CSOM) in children in Garissa district, Kenya: a point prevalence study

OBJECTIVES

To identify by type and sensitivity to drugs the bacteria found in ears of school-going children with chronic otitis media in Garissa district.

STUDY DESIGN

This was a descriptive prevalence study of CSOM bacterial flora in eligible ears conducted among a cohort of children attending public and private primary as well as Islamic religious schools, screened for chronic ear discharge in Garissa district, Kenya. Procedure and bacteriological techniques: We used sterile swab-sticks to collect a specimen of the discharge from eligible ears of consenting pupils at the induction stage of the zinc supplementation trial for treatment of chronic suppurative otitis media conducted between January and July 2010. All pupils below 18 years present on day of visit were eligible. Both aerobic and anaerobic bacterial cultures were done to identify clinically and epidemiologically important bacteria. Sensitivity tests were based on disc diffusion methods. Results are presented as frequencies and proportions.

RESULTS

Of the pupils seen, 61% were still in pre- or lower primary school. Majority were aged 13 and 14 years. Of the 261 ear swab samples processed, 336 isolates - either in mixed or pure flora - were identified, being almost exclusively aerobes. Proteus spp., Enterococcus, Staphylococcus aureus and Pseudomonas spp. were isolated in 32.7%, 28.6%, 12.8% and 11.3% respectively. Proteus was susceptible to majority of the antibiotics tested for, while Enterococcus was poorly susceptible.

CONCLUSIONS

Aerobic bacteria were most prevalent in this study. Several of the bacteria identified are known to require iron for their growth. This may be important for CSOM treatment if biofilm formation is involved in pathogenesis. Majority of the isolates were susceptible to basic antibiotics compared to Enterococcus bacteria. This portends an important consideration for clinical management and therapeutic decision-making. Additionally, given the prevalence of Enterococcus bacteria, which is an indicator of faecal contamination of the environment, there is need to consider relevant public health components in managing childhood CSOM besides the clinical ones alone.

Microbiology of chronic suppurative otitis media in a tertiary care setup of uttarakhand state, India

Background:

Chronic suppurative otitis media (CSOM) is a notorious infection and a major health problem in developing countries causing serious local damage and threatening complications. Early and effective treatment based on the knowledge of causative micro-organisms and their antimicrobial sensitivity ensures prompt clinical recovery and possible complications can thus be avoided.

Aims:

The aim of this study was to isolate the organisms associated with CSOM and to detect the antibiogram of the aerobic isolates.

Materials and Methods:

A total of 204 patients clinically diagnosed of CSOM were enrolled in the study and the samples were obtained from each patient using sterile cotton swabs and cultured for microbial flora. Drug susceptibility testing for aerobic isolates was conducted using Kirby-Bauer disc diffusion method.

Results:

The most common causative organisms isolated were Staphylococcus aureus (48.69%) and Pseudomonas aeruginosa (19.89%) amongst the 191 aerobic isolates. Anaerobes accounted for 29.41% of the isolates while 12.25% were fungi. Antimicrobial profile of aerobic isolates revealed maximum sensitivity to amikacin (95.5%), ceftriaxone (83.4%) and gentamicin (82.7%).

Conclusion:

Knowing the etiological agents of CSOM and their antimicrobial susceptibility is of essential importance for an efficient treatment, prevention of both complications and development of antibiotic resistance and finally, the reduction of the treatment costs.

Clinical Characteristics of Pediatric Granular Myringitis

Objective

To determine the clinical characteristics of children with granular myringitis.

Study Design

Case series with chart review of children with granular myringitis.

Setting

Tertiary care children’s hospitals in Delaware and Florida.

Subjects and Methods

From July 1, 2006, to June 30, 2011, 15 patients were identified with granular myringitis based on International Classification of Diseases, Ninth Revision code 384.1 (10 male, 5 female; 10 left-sided, 5 right-sided).

Results

Average age at onset was 10 years (range, 4-18 years). Average length of symptoms was 21 months (range, 3-48 months). Thirteen of the 15 patients (87%) had myringotomy tube placement prior to diagnosis of myringitis, and 11 had a previous perforation (73%). Eleven myringoplasties were performed on 8 (53%) patients prior to the onset of granular myringitis (5 fascia, 2 fat, 2 cartilage, 1 paper patch, and 1 at an outside hospital that was unknown). A total of 27 otolaryngologic surgical procedures were done on 14 of 15 patients. Ten patients (67%) had audiometry performed, and 6 (40%) had ear cultures. Medical treatment included ciprofloxacin and dexamethasone otic drops in all patients, oral antibiotics in 4 patients, and additional topical agents in 8 patients. Two patients had laser resurfacing, and 1 patient had surgical curettage. Five patients had long-term remission, 8 had intermittent remission, and 2 had no remission of their symptoms.

Conclusion

Granular myringitis is a chronic, recalcitrant disease typically preceded by myringotomy and tube placement or myringoplasty/tympanoplasty. Medical and surgical intervention is varied and often does not lead to permanent resolution of the disease.

Topical treatment of chronic suppurative otitis media

Chronic suppurative otitis media (CSOM) is a chronic inflammation of the middle ear and mastoid cavity presenting with ear discharge or otorrhea through a non-intact tympanic membrane. CSOM is the most common cause of childhood hearing impairment in developing countries. Accurate diagnosis depends on a high index of suspicion, micro-otoscopic examination, and judicious use of imaging as required. CSOM can be classified into 3 types: tubotympanic, atticoantral, and post-tympanostomy tube insertion. Aerobes, anaerobes and fungi are all potential pathogens in CSOM. This review summarizes the results of recent studies on the bacteriology of CSOM, biofilms, and the role of the nasopharynx pathogens that may have important implications for the treatment of this important pathology; that is often associated with misdiagnosis or delayed diagnosis. Particular emphasis will be placed on topical treatment options including choices of antibiotic, antifungal, and antiseptic agents, delivery technique, spectrum of activity, and risk of ototoxicity.

Otitis media

Otitis media represents a broad spectrum of disease, which include acute otitis media and otitis media with effusion. As immunization with the pneumococcal conjugate vaccine has become more widespread, the microbiological landscape of otitis media has changed, which affects the treatment options facing clinicians worldwide. This review discusses the diagnosis and medical management of acute and chronic suppurative otitis media, the changes noted over the past decade, and briefly expounds on the surgical management of their severe complications.

Relationship between oral anaerobic bacteria and otitis media with effusion

OBJECTIVE

In this study hypothesing the translocation of oral bacteria from oropharynx into the middle ear cavity may be involved in the pathogenesis of otitis media with effusion (OME), we aimed to investigate the presence and similarity of Fusobacterium nucleatum and Treponema denticola in saliva, nasopharyngeal secretion and the middle ear effusion samples from the children with OME.

METHODS

Totally 20 children with OME undergoing myringotomy and ventilation tube placement were attended. Stimulated saliva samples were collected after otorhinolaryngological and oral examinations were done. The middle ear effusion and nasopharyngeal secretions were collected during the operations. The presence of F. nucleatum and T. denticola were detected using 16SrRNA-based PCR. The clonal similarities of the bacteria were detected in the samples which the same bacteria had been detected in each samples of the same child. After DNA sequencing, clonal similarity was determined by 16SrRNA gene clone library analysis. The sequences from each clone were compared with similar sequences of reference organisms by FASTA search.

RESULTS

T. denticola was detected only in four (20%) saliva and in one (5%) nasopharyngeal sample. F. nucleatum was detected in 11 (55%) saliva, eight (40%) nasopharyngeal and six (30%) middle ear effusion samples. Sequences from F.nucleatum clones derived from three different anatomic sites within patients were similar in 33% of OME patients, indicating their genetic relatedness.

CONCLUSIONS

Bacteria involved in this process most likely originate from the oropharynx since they show a close genetic relatedness with their oropharyngeal counterparts.

Efficacy of a topical suspension of bacterial antigens for the management of chronic suppurative otitis media

The aim of this study was to compare the efficacy and safety of a topical suspension of bacterial antigens for the management of chronic suppurative otitis media (CSOM). Two-hundred ten patients with CSOM were enrolled in this study. The patients were divided into two numerically equal groups and randomized to receive a topical suspension of bacterial antigens, Lantigen B (group A), or placebo (group B), according to the following protocol: 5 drops thrice a day for 12 consecutive weeks in the external acoustic duct. The topical suspension of bacterial antigens and placebo were administered by identical, anonymous dispensers in order to maintain double-blind conditions. Before, at the end and 3 months, and after the end of the treatment, all patients who entered in the study underwent pure tone audiometry, microscopic examination of ears, microbiological examination of the ear swab, aural suctioning and subjective assessment of symptoms by visual analog scale. In group A, we saw a statistically significant improvement in the different items measured. A topical suspension of bacterial antigens was significantly more effective than placebo in the treatment of CSOM.

Anaerobic brain abscess following chronic suppurative otitis media in a child from Uganda

Brain abscess, while rare, confers high mortality, especially in the developing world. The case of a Ugandan child with a polymicrobial brain abscess including infection with Tissierella praeacuta/Clostridium hastiforme requiring repeated drainage and eventual surgical excision is reported. The case demonstrates the importance of considering anaerobic organisms in the treatment of children with brain abscess from the developing world.

[Correlation between histomorphometric changes and the type of aerobic bacteria isolated in chronic suppurative otitis media]

BACKGROUND/AIM

Bacterial flora is a very important factor in pathogenesis of chronic suppurative otitis media (CSOM) and significantly influences the type and intensity of osteolytic process. There are few histomorphometric investigations of middle ear mucosa in chronic otitis. The aim of this study was to identify aerobic bacteria responsible for chronic suppurative otitis media as well as their association with histomorphometric changes of middle ear mucosa.

METHODS

A prospective study that comprised 153 patients treated in the Clinc for Ear, Thorat and Nose Diseases, Nis, was conducted. Bacteriologic analysis of diseased ear secretion was carried out in all patients. Intraoperatively removed granulation tissue was used for histomorphometry. The analysed parameters were: the number of inflammatory cells, as well as vascularization and vasodilatation.

RESULTS

The most frequently isolated aerobic bacteria from chronic suppurative otitis media were Staphylococcus aureus (29.020/0), Pseudomonas aeruginosa (29.02%) and Proteus spp. (21.76%). There was no correlation between the type of pathologic process and the type of bacteria. The number of inflammatory cells in the granulation tissue in pure cultures of Staphylococcus aureus was 1,597.33 +/- 549.45 and in Pseudomonas aurzginosa cultures was 2639 +/- 648.

CONCLUSION

This study showed that there is a statistically significant correlation between the number of inflammatory cells in the granulation tissue and the type of aerobic bacteria we isolated. The intensity of the infection in chronic suppurative otitis media depends on the type of the isolated bacteria, which emphasizes the importance of adequate preoperative antimicrobial therapy.

Sensorineural hearing loss in patients with chronic suppurative otitis media

Even though there are other complications of chronic suppurative otitis media, the aspect of hearing loss is often studied. Nevertheless, the occurrence of sensorineural hearing loss in patients with this disease is still controversial. This study aim (1) to assess the association between sensorineural hearing loss and chronic suppurative otitis media, (2) to investigate some clinical factors that might affect the sensorineural component in patients with this disease. This was a retrospective analysis of the clinical records and pure tone audiograms of patients with chronic suppurative otitis media in a Nigerian Tertiary Health Institution from January 2003 to December 2008. Sixty-nine patients with a mean age of 28.93 years; standard deviation of 18.593 were studied. They had an age range of 4-73 years. The duration of otorrhea ranged from 2 months to 20 years; with a mean of 6.11 years (standard deviation of 6.393). The mean bone conduction threshold in the diseased ear was 39.07 dB (standard deviation of 12.028), and 10.26 dB (standard deviation of 2.620) in the control ear (P < 0.05). The mean bone conduction threshold differences between the diseased and control ears range from 21.69 to 34.52 dB across the frequencies 0.5, 1.0, 2.0, and 4.0 kHz. These differences tended to increase with increasing frequency and were all significant (P < 0.05). In the diseased ears, there were no significant correlation between the age, duration of otorrhea, and the degree of SNHL (r = 0.186, P > 0.05; r = 0.190, P > 0.05 respectively). Patients with chronic suppurative otitis media had a significant degree of sensorineural hearing loss in this study. The higher frequencies were more affected; however, the patient's age and duration of otorrhea seem not to have any correlation with the degree of sensorineural hearing loss.

Anaerobic infections: update on treatment considerations

Anaerobic bacteria are the predominant indigenous flora of humans and, as a result, play an important role in infections, some of which are serious with a high mortality rate. These opportunistic pathogens are frequently missed in cultures of clinical samples because of shortcomings in collection and transport procedures as well as lack of isolation and susceptibility testing of anaerobes in many clinical microbiology laboratories. Correlation of clinical failures with known antibacterial resistance of anaerobic bacteria is seldom possible. Changes in resistance over time, and the discovery and characterization of resistance determinants in anaerobic bacteria, has increased recognition of problems in empirical treatment and has even resulted in changes in treatment guidelines. This review discusses the role of anaerobic bacteria in the normal flora of humans, their involvement in different mixed infections, developments in antibacterial resistance of the most frequent anaerobic pathogens and possible new treatment options.