A core outcome set for research on the management of otitis media with effusion in otherwise-healthy children

INTRODUCTION

A Core Outcome Set (COS) is an agreed list of outcome domains to be reported by all studies investigating a condition. A COS for Otitis Media with Effusion (OME) in children with cleft palate exists (called MOMENT), but there isn't one for otherwise-healthy children. This study investigates whether the MOMENT COS could also be applicable to otherwise-healthy children.

METHODS

A long list of potential outcomes was generated (independently of MOMENT) via three methods: literature review to establish which outcomes are reported by OME studies, a review of outcomes contained in OME questionnaires, and a focus group asking parents of children with OME what matters to them. The long list drawn up using these sources identified no outcomes additional to ones in the MOMENT long list. An online questionnaire was subsequently undertaken, asking parents/guardians and professionals/researchers whether they think that the MOMENT final list outcomes would also be applicable to otherwise healthy children.

RESULTS

A total of 134 people took part: 53 parents/guardians (recruited through UK NHS hospitals) and 81 professionals/researchers (recruited internationally). Overall, 128 (95.5%) agreed that the MOMENT outcomes can also apply to otherwise healthy children (100% parents/guardians, 92.6% professionals/researchers).

CONCLUSIONS

The outcome domains identified in the COS for OME management in children with cleft palate can also be used in otherwise-healthy children.

OMQ-14 and ECLiPS questionnaires: Potential adjuncts in the assessment of otitis media with effusion?

OBJECTIVE

To assess the capacity of two parental report questionnaires, OMQ-14 and ECLiPS, to support clinical-decision making in children affected by Otitis Media with Effusion (OME).

DESIGN

OMQ-14 and ECLiPS were administered twice to 90 children aged 2-12 years, three months apart, or 3 months after surgery to insert ventilation tubes (VT). Children were subdivided according to clinical diagnosis into VT (n = 25) and Active Observation (AO; n = 20), and compared with healthy control children (n = 45). Data were analyzed at group level using repeated measures ANOVA, and at individual level using Receiver Operator Characteristics (ROC) curves and confusion matrices.

RESULTS

Both OMQ-14 and ECLiPS were sensitive to the presence of OME, and also to improvements in hearing post-surgery. Both were also good at classifying children into their clinically-established diagnostic groups based on score cut-offs determined using Receiver Operator Characteristics (ROC) curves. However, outputs from confusion matrices suggest only around 50% of children after VTs would be indistinguishable from controls following VT surgery. Differences were observed in which children were identified as still having problems according to the questionnaires. OMQ-14 is more sensitive to disease-related hearing loss, while the ECLiPS is more sensitive to developmental difficulties.

CONCLUSIONS

Despite being developed with different aims in mind, the OMQ-14 and ECLiPS were similarly sensitive both to symptoms of disease-related hearing difficulty and also to treatment-related improvements in hearing. A significant number of VT children continue to have poor OMQ-14 and ECLiPS scores relative to control children. ECLiPS scores do not always change in a way that hearing improvements would predict, suggesting the ECLiPS is sensitive to wider developmental difficulties. Parental report in the form of narrow or broad-based questionnaires may complement history-taking and audiometry to enhance the quality of discussion between carers and clinicians about OME management.

Evaluation of combinations of putative anti-biofilm agents and antibiotics to eradicate biofilms of Staphylococcus aureus and Pseudomonas aeruginosa

Objectives

To evaluate potential anti-biofilm agents for their ability to enhance the activity of antibiotics for local treatment of localized biofilm infections.

Methods

Staphylococcus aureus and Pseudomonas aeruginosa in vitro biofilm models were developed. The putative antibiotic enhancers N-acetylcysteine, acetylsalicylic acid, sodium salicylate, recombinant human deoxyribonuclease I, dispersin B, hydrogen peroxide and Johnson's Baby Shampoo (JBS) were tested for their anti-biofilm activity alone and their ability to enhance the activity of antibiotics for 7 or 14 days, against 5 day old biofilms. The antibiotic enhancers were paired with rifampicin and clindamycin against S. aureus and gentamicin and ciprofloxacin against P. aeruginosa. Isolates from biofilms that were not eradicated were tested for antibiotic resistance.

Results

Antibiotic levels 10× MIC and 100× MIC significantly reduced biofilm, but did not consistently eradicate it. Antibiotics at 100× MIC with 10% JBS for 14 days was the only treatment to eradicate both staphylococcal and pseudomonal biofilms. Recombinant human deoxyribonuclease I significantly reduced staphylococcal biofilm. Emergence of resistance of surviving isolates was minimal and was often associated with the small colony variant phenotype.

Conclusions

JBS enhanced the activity of antibiotics and several other promising anti-biofilm agents were identified. Antibiotics with 10% JBS eradicated biofilms produced by both organisms. Such combinations might be useful in local treatment of localized biofilm infections.

Anti-confocal assessment of middle ear inflammation

To improve the diagnostic prediction of recurrence of otitis media with effusion after surgery, an anti-confocal system combined with spectroscopic measurements is proposed to reject unwanted signals from the eardrum and assess the blood content. The anti-confocal system was experimentally evaluated on both optical middle ear phantom and human skin. Results showed effective rejection of signals from the eardrum using a central stop replacing the confocal pinhole, while still detecting signals from the middle ear mucosa. The system is sensitive to changes in blood content, but scattering and absorption characteristics of the eardrum can distort the measurement. Confocal detection of eardrum properties was shown to be a promising approach to correct measurements.

Which outcome measures are reported by clinical trials investigating OME treatment? A case for standardised reporting

INTRODUCTION

Many different OME treatment trials have been published using different outcomes measures to evaluate the success of particular interventions. We set out to identify the variation in reporting of outcome measures in OME trials that exists at present. This has been achieved by reviewing published trials to determine which outcome measures have been reported.

METHOD

The literature review was carried out using PUBMED database (1980 to 2013). Data were collected on the treatment outcomes reported, with particular focus on the methods of assessment and the number of treatment outcomes used in each study.

RESULTS

The 171 studies identified used 12 broad treatment outcome measures. The most common outcome measure was OME resolution (48%) followed by hearing level (36%). Only 95 studies used a single outcome measure, with 76 studies using between 2 and 4 outcome measures. The method of assessment varied between studies that used the same treatment outcome measures.

CONCLUSION

OME treatment trials report a wide range of measures and comparison across studies is thus difficult. Establishing a core set of outcome measures to be reported by all trials in the future could be useful, and would allow comprehensive comparison of different studies and minimise potential for reporting bias.

Anti-confocal versus confocal assessment of the middle ear simulated by Monte Carlo methods

The ability to monitor the inflammatory state of the middle ear mucosa would provide clinical utility. To enable spectral measurements on the mucosa whilst rejecting background signal from the eardrum an anti-confocal system is investigated. In contrast to the central pinhole in a confocal system the anti-confocal system uses a central stop to reject light from the in-focus plane, the eardrum, with all other light detected. Monte Carlo simulations of this system show an increase in detected signal and improved signal-to-background ratio compared to a conventional confocal set-up used to image the middle ear mucosa. System parameters are varied in the simulation and their influence on the level of background rejection are presented.

Guinea Pig Model to Establish the Safety of Middle Ear Pellets

Objectives:

Effective treatments for otitis media with effusion (OME) remain elusive as many patients have recurrence. Direct drug delivery to the middle ear has the potential to maximize efficacy, minimize side effects, and provide a sustained release treatment, which is particularly important in the treatment of biofilms. Polymer-based pellets are delivery vehicles for antibiotics and pellet placement in the middle ear is a potential future OME treatment. In vivo testing of these pellets in animal models is necessary prior to human application.

Methods:

Twenty-four adult guinea pigs were divided into 3 (n = 8) treatment groups: biological controls, surgical controls, polylactic glycolic acid (PLGA) pellets inserted in middle ear. The surgical approach involved submandibular incision, dissection, and following digastric up to the middle ear bulla. Perforating the bulla wall facilitated a 2.5-mm diameter pellet insertion. Auditory brainstem responses (ABRs) were recorded at 0, 1, 2, 4, and 16 weeks at 6 frequencies over 8 to 30 kHz. Analysis was performed using a paired t test with significance set at P < .05 (Bonferroni correction).

Results:

Mean ABR thresholds across the 3 groups ranged between 42 and 49 dB SPL over 4 weeks. There were statistically significant threshold elevations between 4-10db SPL in the surgical control and pellet groups although these were not considered physiologically significant.

Conclusions:

Using a guinea pig model, PLGA pellet insertion into the middle ear caused ABR threshold elevation of only 4-10 dB SPL, supporting their use as a potential vehicle for middle ear drug delivery.

Update on otitis media - prevention and treatment

Acute otitis media and otitis media with effusion are common childhood disorders, a source of significant morbidity, and a leading cause of antibiotic prescription in primary health care. Although effective treatments are available, some shortcomings remain, and thus better treatments would be welcome. Recent discoveries within the field of otitis media research relating to its etiology and pathogenesis have led to further investigation aimed at developing novel treatments. This article provides a review of the latest evidence relating to the understanding of acute otitis media and otitis media with effusion, current treatment strategies, their limitations, new areas of research, and novel strategies for treatment.

Development of a porous poly(DL-lactic acid-co-glycolic acid)-based scaffold for mastoid air-cell regeneration

OBJECTIVES/HYPOTHESIS

To develop a porous, biodegradable scaffold for mastoid air-cell regeneration.

STUDY DESIGN

In vitro development of a temperature-sensitive poly(DL-lactic acid-co-glycolic acid)/poly(ethylene glycol) (PLGA/PEG) scaffold tailored for this application.

METHODS

Human mastoid bone microstructure and porosity were investigated using micro-computed tomography. PLGA/PEG-alginate scaffolds were developed, and scaffold porosity was assessed. Human bone marrow mesenchymal stem cells (hBM-MSCs) were cultured on the scaffolds in vitro. Scaffolds were loaded with ciprofloxacin, and release of ciprofloxacin over time in vitro was assessed.

RESULTS

Porosity of human mastoid bone was measured at 83% with an average pore size of 1.3 mm. PLGA/PEG-alginate scaffold porosity ranged from 43% to 78% depending on the alginate bead content. The hBM-MSCs proliferate on the scaffolds in vitro, and release of ciprofloxacin from the scaffolds was demonstrated over 7 to 10 weeks.

CONCLUSIONS

The PLGA/PEG-alginate scaffolds developed in this study demonstrate similar structural features to human mastoid bone, support cell growth, and display sustained antibiotic release. These scaffolds may be of potential clinical use in mastoid air-cell regeneration. Further in vivo studies to assess the suitability of PLGA/PEG-alginate scaffolds for this application are required.

Bacterial involvement in otitis media with effusion

OBJECTIVE

Otitis media with effusion (OME), a common chronic childhood condition affecting hearing, is thought to be a result of bacterial infection, with biofilms recently implicated. Although bacterial DNA can be detected by polymerase chain reaction in 80% of patients, typically fewer than half of effusions are positive using standard culture techniques. We adopted an alternative approach to demonstrating bacteria in OME, using a bacterial viability stain and confocal laser scanning microscopy (CLSM): staining allows detection of live bacteria without requiring growth on culture, while CLSM allows demonstration of the three-dimensional structure typical of biofilms.

METHODS

Effusion samples were collected at the time of ventilation tube insertion, analysed with CLSM and bacterial viability stain, and extended culture techniques performed with the intention of capturing all possible organisms.

RESULTS

Sixty-two effusions (42 patients) were analysed: 28 (45.2%) were culture-positive, but 51 (82.3%) were CLSM-positive. Combining the two techniques demonstrated live bacteria in 57 (91.8%) samples. Using CLSM, bacteria exhibited biofilm morphology in 25 effusions and were planktonic in 26; the proportion of samples exhibiting biofilm morphology was similar in the culture-positive and culture-negative groups (50.0% and 48.3%, respectively). Biofilm samples contained an average of 1.7 different bacterial isolates and planktonic samples 2.0, with the commonest bacteria identified being coagulase-negative staphylococci.

CONCLUSION

Live bacteria are present in most effusions, strongly suggesting that bacteria and biofilms are important in the aetiopathogenesis of OME.

The localization of matrix metalloproteinases-8 and -13 in cholesteatoma, deep-meatal and post-auricular skin: a comparative analysis

CONCLUSION

The presence of matrix metalloproteinase (MMP)-8 and MMP-13 was found to be significantly higher in cholesteatoma compared with post-auricular skin. The results show that the control group used has implications for further studies.

OBJECTIVES

To compare the presence of MMP-8 and MMP-13 in cholesteatoma, deep meatal and post-auricular skin. Our null hypothesis was that there was no difference in expressions of MMP-8 and MMP-13 in the three groups.

MATERIALS AND METHODS

The study was carried out in a secondary care specialist centre and used prospective retrieval of specimens for immunohistological localization of MMP-8 and MMP-13. Eleven patients undergoing cholesteatoma surgery were recruited for the study. Eleven cholesteatoma specimens, 10 deep meatal skin specimens and 10 post-auricular skin specimens were analysed. Specimens were analysed by immunohistochemistry using monoclonal antibodies to MMP-8 and MMP-13. Two observers scored the slides independently in a blind fashion.

RESULTS

The presence of MMP-8 and MMP-13 was found to be significantly higher in cholesteatoma compared to post-auricular skin (p=0.02, p=0.03, respectively). There were no significant differences in expression of MMP-8 and MMP-13 between cholesteatoma and deep meatal skin (p=0.08, p=0.09, respectively). There were no significant differences in the control groups.

Evidence of T-helper cell 2 cytokine regulation of chronic otitis media with effusion

Cytokine and cellular patterns of effusions may reflect stages of middle ear inflammation. The local interplay between IL-2 and -4 is likely to play a crucial role in the switching of inflammation in the chronic stage. The T-helper cell 2 (Th2) cytokines IL-4, -5 and -13 and the Th2/Th1 cytokine granulocyte-macrophage colony-stimulating factor (GM-CSF) regulate the cellular and molecular processes of chronic inflammation in the middle ear and therefore the chronic condition of otitis media with effusion (OME). Early identification of the cytokine and cellular patterns of effusions can be helpful in directing the clinical treatment of OME.We hypothesized that IL-2 and the group of Th2 cytokines regulate chronic inflammation in the middle ear and chronic OME. Effusions from children with persistent OME were analysed to determine the presence of cytokines (the Th1 cytokine IL-2, the Th2 cytokines IL-4, -5 and -13 and the Th1/Th2 cytokine GM-CSF), inflammatory cells (CD4+ T cells, eosinophils, macrophages and neutrophils) and mucin. Cytokines were evaluated by means of a quantitative "sandwich"-type ELISA, inflammatory cells by means of alkaline phosphatase-anti-alkaline phosphatase immunocytostaining and mucin by means of a modified periodic acid-Schiff method based on a slot-blot technique. The cytokine pattern in effusions varied from patient to patient. GM-CSF correlated positively and IL-4 inversely with IL-2 and the increased level of IL-4 may have had an inhibitory effect on IL-2. IL-5 and -13 correlated with IL-4. Inflammatory cells correlated with cytokines as follows: CD4+ T cells with IL-2 and -4; macrophages and neutrophils with GM-CSF; and eosinophils with IL-5. Some cytokine-cellular correlations in effusions were reflected at the clinical level. The mucin content of effusions correlated with the concentrations of IL-4 (>10 pg/ml) and -13, suggesting involvement of IL-4 and -13 in upregulation of the middle ear mucin metabolism.

The immunoregulatory and allergy-associated cytokines in the aetiology of the otitis media with effusion

Inflammation in the middle ear mucosa, which can be provoked by different primary factors such as bacterial and viral infection, local allergic reactions and reflux, is the crucial event in the pathogenesis of otitis media with effusion (OME). Unresolved acute inflammatory responses or defective immunoregulation of middle inflammation can promote chronic inflammatory processes and stimulate the chronic condition of OME. Cytokines are the central molecular regulators of middle ear inflammation and can switch the acute phase of inflammation in the chronic stage and induce molecular-pathological processes leading to the histopathological changes accompanying OME. In this review we present cytokines identified in otitis media, immunoregulatory [interleukin (IL)-2, IL-10, transforming growth factor-beta]) and allergy associated (IL-4, IL-5, granulocyte-macrophage colony-stimulating factor), as crucial molecular regulators, responsible for chronic inflammation in the middle ear and the chronic condition of OME.

Is otitis media with effusion a biofilm infection?

Recent attention has focused on the possibility that otitis media with effusion (OME) may represent a chronic infective state such as those evidenced in conditions secondary to biofilms or small colony variants. This review discusses the evidence suggesting that this may indeed be the case and explains why this may prove to be important in the future management of this condition by discussing recent advances in understanding these bacterial phenotypic variants.

Bony remodelling in an osteoma of the paranasal sinuses

Osteoma is the commonest benign tumour of the paranasal sinuses (Handousa, 1952). A case of a large osteoma removed from the frontal and ethmoid sinuses is presented. Histopathological examination of this tumour revealed evidence of bony remodelling similar to that seen in Paget's disease which has not been previously reported. The pathological significance of this finding is discussed.

Short-term learning effects of practice during the performance of the tandem Romberg test

The tandem Romberg test is possibly the most common static test of postural stability. This study aims to see if practice effects the performance of the tandem Romberg test. Twenty-four subjects were instructed to practice the tandem Romberg test daily for a period of 10 consecutive days, and were tested on five occasions using the sway magnetometry posturographic system. The test was performed with eyes open and eyes closed either on the floor or on foam. Their ability to perform the test for 60 s was used as a pass/fail criterion. With eyes closed, 65% of tandem Romberg tests were successful on hard surface, and 28% on foam. With eyes open, all subjects scored a 'pass'. On hard surface, the mean path length for the first and last day was 371.7 mm (SD 68.56) and 481 mm (SD 145.47) respectively. On foam, it was 506 mm (SD 139) and 530 mm (SD 212). For the 'fail' tandem Romberg tests, the 75th percentile for the time taken for subjects to perform the test on the first and last days were 18.5 and 9 s on floor, and 18 and 37 s on foam respectively. Across all testing sessions and groups, no significant improvement in performance with practice was observed. The absence of improvement in subjects practising the tandem Romberg test indicates a lack of short-term learning effects. The failure rate, however, associated with eye closure, whether on foam or on hard surface, invalidates the use of the tandem Romberg test in assessing postural stability because of its performance variability.

Postural stability of preoperative acoustic neuroma patients assessed by sway magnetometry: are they unsteady?

OBJECTIVE

The objective was to evaluate the preoperative postural stability of acoustic neuroma patients using sway magnetometry.

STUDY DESIGN

Prospective two-center study.

METHODS

Fifty-one patients (mean age, 53 years) diagnosed with unilateral acoustic neuroma on magnetic resonance imaging at two tertiary referral centers were studied. Preoperatively, each patient had sway patterns (with eyes open and with eyes closed, and standing on foam) recorded for 120 seconds by sway magnetometry. Path length for 30 seconds was calculated. The Romberg coefficient (path length with eyes open divided by path length with eyes closed) was calculated.

RESULTS

Forty-four percent of patients had abnormal path lengths with eyes open, and 49% with eyes closed. The Romberg coefficients were significantly lower than normal (P <.001; 95% CI, 0.19-0.87). Mean Romberg coefficient was 0.59 (normal value = 0.73), and all patients had a coefficient of less than 1.

CONCLUSIONS

Half of preoperative acoustic neuroma patients are unsteady, exhibiting abnormal sway patterns based on path length measurements. The increase in sway path length demonstrable in normal subjects with eyes closed was significantly exaggerated in patients with acoustic neuroma.

Influence of prednisolone on the secretion of mucin from the HT29-MTX cell line

Glucocorticoids have been used in the treatment of otitis media with effusion with promising but inconsistent results. The HT29-MTX cell line is a completely differentiated and almost exclusively mucus-secreting goblet cell line. To assess the potential of steroids in suppressing mucin secretion, we have studied the response of this cell culture to prednisolone. Confluent cell cultures were trypsinized, subcultured in six-well plates and incubated with five doses of prednisolone from 10-3 M to 10-11 M and over a varying time course from 6 to 36 h. Analysis was performed using a monoclonal mouse antibody to human gastric mucin by dot-blot ELISA. Prednisolone caused a consistent reduction in mucin production from this cell line. Increasing concentrations of prednisolone resulted in increasing suppression of MUC5AC secretion. There is a dose-dependent suppression of mucin secretion by prednisolone, with a maximum effect of 21% over control seen at the highest steroid concentration used.

Effect of nitric oxide donation on mucin production in vitro

Otitis media with effusion (OME) is characterized by the accumulation of a viscous fluid rich in mucins in the middle ear cleft. There is increasing evidence that this fluid is the result of an inflammatory reaction and that nitric oxide (NO) is an important mediator in this reaction. The goblet cell line HT29-MTX produces principally MUC5AC, an important mucin in middle ear effusions, and thus is a good model for the study of mucus-secreting epithelia. Confluent cell cultures were trypsinized, subcultured and incubated with isosorbide dinitrate (ISDN), a NO donor, for 0.5, 1 and 2 h at a concentration of 1 mm and in concentrations of 0.01, 0.1, 0.5, 1 and 2 mm for 1 h. Experiments were performed four times. Mucin production was detected by a slot blot ELISA assay, using a monoclonal mouse antibody to human MUC5AC mucin. Statistical significance was tested using a one-way analysis of variance. NO donation by ISDN caused a consistent rise in mucin production above control. Maximal mucin production of 35% above control occurred at 1 h with 1 mm ISDN. Mucin production increased from 12% above control with 0.1 mm ISDN dinitrate to 45% above baseline with 2 mm ISDN. NO donation by ISDN results in an increase in mucus production, which is both dose and time related. This adds further evidence to an inflammatory model for mucus secretion in OME.

LPS up-regulates mucin and cytokine mRNA expression and stimulates mucin and cytokine secretion in goblet cells

Bacterial inflammation in mucosa is accompanied by morphological and proliferative changes in goblet cells and mucin hypersecretion. Main stimulators of bacterial inflammation are bacterial lipopolysaccharides (LPS). In vitro investigation of the LPS effect on the molecular processes in goblet cells, using the human mucin-secreting goblet cell line HT29-MTX, showed the following results. LPS up-regulated mucin and cytokine mRNA expression and secretion in goblet cells in a concentration and time-dependent manner, with a maximum output at an LPS concentration of 100 ng/ml. LPS (100 ng/ml) increased mRNA expression of MUC5AC (2.4x), MUC5B (2.1x), and IL-8 (2.3x) and stimulated secretion of mucins (MUC5AC up to 39%, MUC5B up to 31%) and the inflammatory cytokine IL-8 (up to 10x). A significant correlation was found between the LPS-induced IL-8 secretion and secretion of mucins. These results suggest: (1) goblet cells, responding to the direct stimulation of bacterial LPS by two inflammatory-related processes such as production and secretion of the gel-forming mucins and the inflammatory cytokine IL-8, can be considered as an important part of mucosal immunity and (2) LPS- induced goblet cell mucin secretion can occur partly via IL-8-dependent pathway.

p53 Expression and keratinocyte hyperproliferation in middle ear cholesteatoma

Keratinocytes in middle ear cholesteatoma have hyperproliferative properties. There is controversy regarding the role of p53 and its effect on cellular proliferation in cholesteatoma. This study was instituted to examine this. Cholesteatoma and deep meatal skin control specimens were analysed for MIB-1 (n = 7, controls = 7), a marker of cellular proliferation, and p53 (n = 17, controls = 17) expression by immunocytochemistry. Expression of p53 was minimal or absent in both cholesteatoma and controls (P = 0.2). MIB-1 expression was higher, but not significantly so, in cholesteatoma than in controls (P = 0.09). Our study has shown no significant p53 expression in cholesteatoma epithelium. This suggests that there is no dysfunction in the p53-mediated cell cycle control mechanisms in cholesteatoma.

Role of the pro-inflammatory cytokines tumor necrosis factor-alpha, interleukin-1 beta, interleukin-6 and interleukin-8 in the pathogenesis of the otitis media with effusion

Inflammation in the middle ear mucosa, caused usually by bacterial and viral pathogens, is the primary event in the middle ear predisposing the development of otitis media with effusion (OME). Numerous inflammatory mediators have been identified in OME. However, cytokines play a central role as initiators, mediators and regulators of middle ear inflammation and subsequent molecular-pathological processes in middle ear tissues, leading to histopathological changes in the middle ear cavity and the pathogenesis of OME. In this article, we aim to present an overview of current research developments in the pro-inflammatory cytokine involvement in the aetiology of otitis media with effusion.

In vitro study of IL-8 and goblet cells: possible role of IL-8 in the aetiology of otitis media with effusion

One of the main characteristics of otitis media with effusion (OME) is the differentiation of basal cells into goblet cells with subsequent proliferation in a modified respiratory epithelium leading to the formation of mucin-rich effusion in the middle ear cleft. In order to determine the effect of pro-inflammatory cytokines identified in OME, e.g. IL-1beta, tumour necrosis factor (TNF)-alpha, IL-6 and IL-8, on goblet cells, and to clarify the role of IL-8 in particular, we used the human goblet cell line HT29-MTX, which secretes two OME-related mucins: MUC5AC and MUC5B. IL-1beta and TNF-alpha stimulated the secretion of IL-8 in HT29-MTX goblet cells. Dose- (2-200 ng/ml) and time- (0-5 days) response studies of IL-8-induced mucin secretion were carried out. IL-8 upregulated the secretion of MUC5AC and MUC5B mucins in a concentration-dependent manner, with a maximum response at an IL-8 concentration of 20 ng/ml. IL-8 (20 ng/ml)-mediated mucin secretion persisted for up to 5 days, with a peak response 72 h after the addition of cytokine. These results suggest that: (i) goblet cells are target cells for the pro-inflammatory cytokines IL-1beta, TNF-alpha and IL-8 and can contribute to the pathogenesis of OME by increasing both the concentration of IL-8 and the secretion of mucin; and (ii) IL-8 stimulates prolonged mucin secretion from goblet cells and may be involved in the maintenance of the disease in the chronic stage.

Reflux of gastric juice and glue ear in children

Otitis media with effusion (glue ear) is the most frequent cause of deafness in children. We investigated the role of gastric juice reflux in this disease. We measured pepsin concentrations in middle ear effusions from children using ELISA and enzyme activity assays. 45 (83%) of 54 effusions contained pepsin/pepsinogen at concentrations of up to 1000-fold greater than those in serum. Our data suggest that reflux of gastric juice could be a major cause of glue ear in children.

Matrix metalloproteinases 2 and 9 in otitis media with effusion

A qualitative and quantitative study of the presence of matrix metalloproteinase 2 (MMP 2) and matrix metalloproteinase 9 (MMP 9), in the effusions of otitis media with effusion (OME), was performed. The activity of the above enzymes was compared in thick and thin effusions, and concentrations compared in samples from children with one, two, three and four sets of ventilation tubes. The activity of both MMP 2 and MMP 9 was higher in thick than thin effusions, P = 0.07 and P = 0.04, respectively. The concentrations of MMP 9 did not vary with the number of tube insertions but those of MMP 2 did (ANOVA P < 0.05). MMPs may be involved in tympanic membrane damage and prognosis of OME.

Localization of matrix metalloproteinase 1 in cholesteatoma and deep meatal skin

HYPOTHESIS

Matrix metalloproteinase 1 (MMP-1) is overexpressed in cholesteatoma.

BACKGROUND

Cholesteatoma destroys bone, whereas deep meatal skin does not. MMP-1 is a type I collagenase that may be responsible for this destruction. This prospective study was designed to identify overexpression of MMP-1 by cholesteatoma in comparison with deep meatal skin.

METHODS

Ten cholesteatoma specimens and nine deep meatal skin specimens were removed during otologic surgery and then fixed in formalin and embedded in paraffin. Immunocytochemistry studies were performed using a monoclonal antibody to MMP-1. A pathologist assessed the slides in a blinded fashion. Expression of MMP-1 protein in epidermis and in stroma was scored from 0 to 10. Five further cholesteatoma specimens and three deep meatal skin specimens underwent reverse transcriptase polymerase chain reactions to assess messenger ribonucleic acid production. Paired and unpaired Student's t tests were used to assess the difference in expression levels.

RESULTS

Cholesteatoma stroma expressed significantly more MMP-1 protein than did deep meatal skin stroma (p = 0.04). MMP-1 was localized to stromal fibroblasts. There was no difference in the epidermal expression levels of the two tissue types (p = 0.42). The reverse transcriptase polymerase chain reaction showed expression at the messenger ribonucleic acid size of MMP-1 (262 base pair) in all cholesteatoma specimens examined. One deep meatal skin specimen showed a weak signal; no signal was seen in the other specimens.

CONCLUSIONS

MMP-1 is overexpressed by the stromal fibroblasts present in cholesteatoma as compared with deep meatal skin. It is possible that these cells rather than the keratinocytes are responsible for bone destruction in this disease.

Up-regulation of mucin secretion in HT29-MTX cells by the pro-inflammatory cytokines tumor necrosis factor-alpha and interleukin-6

The pro-inflammatory cytokines IL-6 and TNF-alpha have been implicated in the pathogenesis of otitis media with effusion (OME). A disease where goblet cells proliferate in a modified respiratory epithelium, leading to the accumulation of a mucin-rich effusion in the middle ear cleft. The MUC5AC and MUC5B mucin gene products have been identified as components of these effusions. To determine the effect of IL-6 and TNF-alpha on MUC5AC and MUC5B secretion we have used HT29-MTX goblet cells, which secrete both types of mucins. MUC5AC and MUC5B mucin secretion was measured by an enzyme-linked immunosorbent assay (ELISA) using a specific monoclonal antibody NCL-HGM-45M1 and polyclonal antiserum TEPA, respectively. Time response (0-72 hours) and dose response (1.5-150 ng/ml) studies were carried out. IL-6 and TNF-alpha stimulated MUC5AC and MUC5B mucin secretion in a time dependent manner, both in pre-confluent and post-confluent cells. IL-6 (15 ng/ml and 20 ng/ml) produced a low and prolonged stimulation of mucin secretion that persisted for 72 hours, with peak response at 24 hours after induction. The IL-6-mediated mucin secretion at 24 hours was concentration-dependent, with a maximal effect at 15 ng/ml. TNF-alpha (20 ng/ml) induced rapid stimulation of mucin secretion within the first 24 hours, with peak response at 7 hours after induction. IL-6 and TNF-alpha exposure significantly increased MUC5AC secretion, but not MUC5B secretion. Maximal levels of cytokine-induced mucin secretion were detected in pre-confluent cells that showed one and a half- and two-fold increases in MUC5AC secretion after IL-6 and TNF-alpha stimulation, respectively, in comparison with post-confluent cells. The results presented here suggest that IL-6 and TNF-alpha generate a differential up-regulation of mucin secretion and thus contribute to the expression of mucin genes in inflammatory responses.

The influence of prednisolone on the secretion of MUC5AC from TH29-MTX cell culture

INTRODUCTION: Glucocorticoids have been used in the treatment of otitis media with effusion with promising but inconsistent resluts. The HT29-MTX cell line is a completely differentiated and almost exclusively mucous secreting cell line, which therefore has the potential to act as an ideal model for the study of mucus-secreting epithelia. To assess this potential of steroids in suppressing mucin secretion we have studied the response of the cell culture to prednisolone. METHODS: Confluent cell cultures were trypsinized, subcultured in six-well plates and incubated with four doses of prednisolone from 10-5 M to 10-11 M and over varying time courses from 12 to 36 h. ELISA was performed using a monoclonal mouse antibody to human gastric mucin by dot-blot ELISA. RESULTS: Prednisolone caused a reduction in mucin production from the cell line consistently. Media control values ranged from 3495 to 3559 compared with untreated controls of 18 998-27 176 and steroid treatment values of 12 244-27 792. Increasing concentrations of prednisolone result in increasing suppression of MUC5AC (P = 0.005). There was no independent time-related effect. CONCLUSION: There does appear to be a genuine suppression of mucus production by prednisolone and this appears to be dose-dependent but not time-dependent at the times studied. The effect size was small.

Dynamic assessment of imbalance in acoustic neuroma patients by sway magnetometry

INTRODUCTION: Imbalance may be a significant problem for patients with acoustic neuromas. Prospective data on patients with acoustic neuromas to establish how the vestibular system performs dynamically, in the perioperative phases, is not available. Posturography is an established method of measuring balance and sway magnetometry has been developed as a reliable technique in this field. AIMS: Prospectively to assess pre- and postoperative dynamic vestibular function in patients with acoustic neuromas using sway magnetometry. METHODS: Sway patterns were recorded on 12 patients with acoustic neuromas tested under two sets of conditions: first, a baseline test for 120 s, repeated after 120 s of vestibular stimulation. After each test a validated questionnaire to assess balance subjectively was compeleted: before operation and 1, 3 and 6 months after operation. RESULTS: (1) Patients with acoustic neuromas demonstrate 'overswing' on baseline testing: most exaggerated 1 month postoperatively. After vestibular stimulation the 'recovery' time was prolonged to 50 s postoperatively, 62 s postoperatively (1/12), 43 s (3/12), and 47 s (6/12) postoperatively. (2) Mean path length (normal range, 163-287 mm) was increased in all groups: preoperative = 332 mm, 1 month postoperatively = 358 mm, 3 months postoperatively = 308 and 6 months postoperatively = 343 mm (3) The Dizziness Handicap Inventory scores were elevated at all times of testing and significantly correlated with baseline path length (rs = 0.6, P = 0. 03) and vestibular stimulation path length (rs = 0.7, P = 0.01) preoperatively. CONCLUSIONS: This is the first dynamic, prospective study of balance in patients with acoustic neuromas. Abnormal sway patterns and prolonged recovery times pre- and postoperatively, most marked at 1 month, were demonstrated. A subjective assessment of balance disturbance reflected these abnormal sway measurements confirming its clinical usefulness.

Does the bacterial DNA found in middle ear effusions come from viable bacteria?

INTRODUCTION: Between 20% and 50% of middle ear effusions in otitis media with effusion test positive for bacteria, i.e. H. influenzae, M. catarrhalis and S. pneumoniae. In one study 48% of effusions that tested negative by culture wre positive by polymerase chain reaction (PCR).1 This has been advanced as evidence for the presence of bacterial biofilms, as agents leading to the persistence of glue ear. There is, however, the possibility that the DNA detected is the fossilized remains of bacteria from previously cleared infections. If this is the case, then the effusioin must in some way be protecting the DNA from breakdown by DNases. METHODS: Here we demonstrate, using a viscosity assay, that middle ear effusions taken from children during myringotomy inhibit the breakdown of DNA in a concentration-dependent manner. Middle ear effusion homogenates 0.5-3.0 ml (1 : 10 Vol. vol/effusion: PBS) were incubated with 3 ml of DNA (0.5 mg/ml in PBS) plus 0.2 ml of DNase 1 (500 Kunitz) at 37 degrees C for 24 h. Viscosity measurements were taken at regular intervals and the changes in viscosity expressed as a percentage of time 0. DNase activity was inhibited by 1.5 ml and 3.0 ml of effusion 48% and 91%, respectively, after 30 min incubation. CONCLUSION: This study demonstrated that effusions have the ability to inhibit nuclease activity, and the reported presence of non-culturable bacteria based on DNA detection by PCR could still represent fossilized remains and not viable bacteria. The same could also be true of recent reports of bacterial mRNA.2

TNF-alpha in the regulation of MUC5AC secretion: some aspects of cytokine-induced mucin hypersecretion on the in vitro model

TNF-alpha has been implicated in the aetiology of otitis media with effusion (OME), where goblet cells proliferate in a modified respiratory epithelium, leading to the accumulation of a mucin-rich effusion in the middle-ear cleft. The MUC5AC mucin gene product has been identified as a component of these effusions. Here we have used the HT29-MTX goblet cell line, which secretes MUC5AC mucin, as a model to study the effect of TNF-alpha on goblet cells. MUC5AC mucin was identified and quantitated with a monoclonal antibody NCL-HGM-45M1. TNF-alpha stimulates MUC5AC mucin secretion in a dose-dependent manner, with 20 ng/ml producing maximal stimulation. Both pre-confluent and confluent cells showed peak stimulation after 7 h, however the pre-confluent cells showed twice the level of mucin hypersecretion. These results suggest that TNF-alpha stimulation of mucin secretion could play an important role in the early acute phase of the development of OME. This hypersecretion of mucin could then lead to the failure of the mucociliary clearance system, resulting in the accumulation of a mucin-rich effusion in the middle ear and the movement to a more chronic phase of the disease.

The aetiology of otitis media with effusion: a review

Otitis media with effusion (OME) is the most common cause of deafness in children in the developed world. In this article we aim to present an overview of current research developments on the aetiology of OME and the resulting implications for treatment. In the model we describe, the primary event is inflammation of the middle ear mucosa, usually due to the presence of bacteria. This leads to the release of inflammatory mediators, which cause secretion of a mucin-rich effusion by up-regulating mucin genes. Prolonged stimulation of the inflammatory response and poor mucociliary clearance lead to persistence of the middle ear fluid, giving rise to the clinical presentation of OME. We describe OME in the following sequence: the initial production of the effusion, the composition of the effusion produced, and factors impairing clearance of the effusion.

Heterogeneity in the protein cores of mucins isolated from human middle ear effusions: evidence for expression of different mucin gene products

High molecular weight mucins were isolated and purified from human middle ear effusions of children with Otitis Media with Effusion (OME) classified into three groups, (1) thick and (2) thin from anatomically normal children and (3) effusions from cleft palate patients. Amino acid analyses of the purified mucins from the three pools were similar but not identical with characteristic contents of serine threonine and proline (32%, 28%, and 38% for pools (1) (2) and (3) respectively). Proteinase resistant glycopeptide fragments corresponding to the tandem repeat domains of cloned mucin genes showed marked differences both between the three mucin pools and with the composition of the tandem repeat sequences of the cloned mucin genes expressed in the airways. Studies on the antigenic identity of middle ear mucins found an epitope likely to be present on MUC5AC, but only accounting for a maximum of 15% by weight and no reactivity was found with antibodies to MUC2 or MUC1. A polyclonal antibody raised to thick effusion mucins reacted strongly with human salivary mucin suggesting the presence of MUC5B epitopes. These studies suggest that more than one mucin gene product is secreted by the human middle ear mucosa and that there may be further mucin genes expressed by the middle ear that have yet to be cloned.

Identification of non-organic instability by sway magnetometry

This paper describes the application of sway magnetometry, which objectively measures stability, to assist in the identification of non-organic instability. Three subject groups were studied; 14 normal subjects, 14 subjects with organic dizziness, and 19 subjects assessed as having possible non-organic dizziness before further clinical investigation. Eight of these 19 were subsequently classed as having non-organic dizziness on grounds of their history, clinical examination and standard audio-vestibular investigations. Movement in the horizontal plane at the hips was measured by sway magnetometry in each subject. The absolute and percentage change in path length and area were determined for 15 s before and 15 s after the subject was informed that the test was starting. For absolute path length and area, five out of the eight subjects with non-organic dizziness showed an increase in sway above the upper limit of normal, while only one out of the other 11 subjects in the group showed such an increase (P < 0.02). None of the subjects in the normal or organic group exceeded the upper limit of normal when results were expressed as absolute change in path length or area. Sway magnetometry can provide valuable data to assist the clinician in identification of non-organic dizziness.

Compositional differences between bilateral middle ear effusions in otitis media with effusion: evidence for a different etiology?

The aim of this study was to clarify the site of primary pathology in otitis media with effusion. Effusions were collected from 64 children with bilateral effusions at the time of myringotomy. The rheological properties and biochemical compositions of effusions were measured for 23 pairs of effusions, and the levels of the inflammatory mediators TNF alpha, IL-1beta, and IL-8 were measured in 41 pairs using specific enzyme-linked immunosorbent assays (ELISAs). Measurements from paired ears were compared using analysis of variance (ANOVA) tests and significant differences were found for reduced specific viscosity, mucin content, protein content, and levels of IL-8. The results demonstrate that the two ears have different immunological processes or rates of processes which might explain the significantly different rheological properties of effusions. This suggests that each ear undergoes pathological changes independently and has implications for using the opposite ear as a control in clinical trials.

Measurement of the vestibulo-ocular reflex by magnetometry during active head movement

A new method of measuring the vestibulo-ocular reflex (VOR) during active head movements is presented. Subjects sat and attempted to maintain their gaze upon a fixed point whilst turning their heads from side to side in response to an auditory cue, to attain frequencies of head rotation that increased from 1 Hz to 4 Hz during a 24 s period. Head movements were monitored by a small magnetic field detector worn on the subject's forehead and positioned a set distance from a magnetic field transmitter coil. Eye movements were monitored using the corneo-retinal potential. Gain (eye angle/head angle) and phase difference (eye phase-head phase) were calculated to define the VOR. Three repeat measurements were made on 20 normal subjects. Gain decreased significantly (P < 0.0001) with increasing frequency whilst the phase difference remained unchanged. The 95% prediction intervals were narrow for both gain (+/- 0.28) and phase (+/- 11 degrees). These data, together with the speed and ease of performance of the test, suggest that the test can provide valuable information on the performance of the vestibular system.

The effect of electrode position in electrocochleography

This study assessed the effect of needle electrode position on the human cochlear summating potential (SP) obtained by transtympanic electrocochleography (ECochG). Electrocochleography was performed on 10 subjects with large central tympanic membrane perforations with good cochlear function, and in whom a needle electrode could be accurately placed in a series of five pre-determined positions in the middle ear. A comparison of the electrocochleograms revealed a wide scatter of results between different positions in the same patient and between similar positions in different patients. Only when the needle was repositioned at an almost identical recording site in the same subject, was good reproducibility achieved. Such a wide and unpredictable variation in results would suggest great caution is needed when comparing traces obtained using a transtympanic technique which precludes a view of the electrode tip.

Fourth branchial arch fistula

A case is presented of a rare congenital anomaly of the fourth branchial arch, which presented as an abscess in the anterior triangle, related to a fistula communicating with the pyriform fossa. Histopathological examination showed the fistula to be associated with thyroid tissue supporting the hypothesis that the ventral wing of the fourth pouch contributes to the thyroid gland.

Bilatral auriculotemporal syndrome in childhood

A case of bilateral Auriculotemporal or Frey's syndrome in childhood is unique in the World literature. The clinical presentation and management is discussed. A conservative approach is advocated but other therapeutic options are considered. The literature is reviewed, only 17 cases all unilateral are known, and from the study the probable aetiology and long term follow-up is reported.

Occupational rhinitis--possible mechanisms of pathogenesis

Occupational rhinitis has been a prescribed industrial disease in the UK since 1907. It has only relatively recently received significant attention from otorhinolaryngologists although numerous studies have been performed in the past by occupational and industrial health physicians. At the present time the precise mechanisms of pathogenesis are unclear and would appear to be multiple. Recently interest has arisen because of compensation claims. Diagnosis made on the basis of the clinical history is subject to two problems: firstly, there is difficulty in differentiating between occupational and nonoccupational rhinitis, and secondly, clinical histories can easily be feigned. Physical signs would be a more reliable indicator of occupational damage to the nasal mucosa if they differ from the signs normally found in allergic or vasomotor rhinitis. In a series of 100 shipyard workers dry atrophic nasal mucosa was found in 66 and septal ulceration in two. From their clinical histories 78 individuals complained of nasal obstruction, 28 of epistaxis, 42 of hyposmia, 10 of anosmia and 90 of rhinorrhoea. Possible pathogenesis is described.

Should we routinely screen for Lyme disease in patients with asymmetrical hearing loss?

Asymmetrical sensorineural hearing loss is usually investigated thoroughly but a diagnosis is often elusive. It is important to identify any treatable causes. Lyme disease is a tick-borne infection caused by the spirochaete Borrelia burgdorferi, which has been shown to cause asymmetrical sensorineural hearing loss, and has been successfully treated. Its incidence varies regionally; it occurs where there is a suitable environment for the tick and its animal hosts. We conducted a prospective study of 100 patients with asymmetrical sensorineural hearing loss. Serological testing for Lyme disease was performed. One patient had positive serology, but there was no improvement in her hearing following antibiotic treatment. We cannot conclude that our patient's hearing loss was caused by Lyme disease. We suggest that routine screening is not cost effective in regions with a low incidence of Lyme disease.

Comparison of body sway analysis techniques. Assessment with subjects standing on a stable surface

Different analysis methods for the objective measurements of body sway were examined to establish the most sensitive method for identifying changes in stability. Changes between stability with eyes open and eyes closed were used to assess the techniques. Body sway was measured in a group of normal subjects standing on a stable surface using "sway magnetometry," which measures hip movement in the sagittal and coronal planes by magnetic field detectors worn at the waist. The following analysis methods were studied; path length, mean distance from the centre, the area enclosed by the path of movement, and the areas of a convex hull, an ellipse and a circle enclosing the sampled points. The results showed that the path length technique had the smallest inter-subject variability, both with eyes open and eyes closed, and was the only technique whose mean Romberg Coefficient (Eyes Open/Eyes Closed) was more than two standard derivations from 1.0 (0.74 +/- 0.11, mean +/- S.D.), indicating that this technique showed greatest sensitivity for detecting changes in body sway.

Preliminary characterization of mucin from effusions of cleft palate patients

Middle ear effusions from children undergoing myringotomy were classified into three groups-cleft palate, thick (mucoid), and thin (serous). Mucin was purified from each of the three groups using CsCI equilibrium density gradient centrifugation. Analysis of the cleft palate mucin on Sepharose CL-2B showed it was excluded and therefore of large molecular weight. It could be broken down into smaller glycopeptide units by proteolysis and these glycopeptides had, based on elution position, a larger hydrodynamic size than those from the thick mucin. Intrinsic viscosity measurements demonstrated that the intact mucins could be ranked in order of molecular space occupancy; cleft palate > thick > thin. Amino acid analysis showed the cleft palate mucin to have an amino acid composition similar to other mucins, with serine, threonine, and proline constituting 41% by weight of the protein core. Thiol analysis gave evidence of a possible difference in polymerization between the three mucins, in that thin (the smallest mucin) contained the lowest number of thiols. This preliminary analysis of cleft palate mucin suggests a mucin with larger glycopeptide units forming an intact mucin of larger hydrodynamic size than either thick or thin middle ear mucins from anatomically normal children.

An assessment of the reproducibility of combined glottography in a clinical setting

Although combined glottography has potential as a clinical tool, it has had limited use in the monitoring of laryngeal function before and after treatment. There is no data about the standardization nor reproducibility of the procedure. An indication of the reproducibility of combined glottography is paramount if changes in laryngeal function are to be measured accurately. Using a standardized technique, two complimentary studies examined the reproducibility of combined glottography within one sitting (Study 1) and over time (Study 2). The components of variance were analysed (ANOVA). In Study 1 the variance under controlled conditions for Open Quotient (OQ) and Speed Quotient (SQ) was only 13% and 18% respectively of the total, whilst in Study 2 the variance over time for OQ and SQ was 55% and 58% respectively. Under controlled conditions combined glottography is a reproducible technique.

A comparison of combined glottography in men and women

Out-patient combined glottography has shown potential in the assessment of the vocal cord cycle in laryngeal abnormality. We compared this technique in men and women with normal laryngeal function, to evaluate the influence of patient sex on the results. Ten adult men were compared with 10 age matched women. The open quotient was significantly greater in women. This indicates the woman's glottis is open for a greater proportion of the glottic cycle, as a result of the anatomical and physiological differences of the larynx between the sexes. Analyses are made of the glottic cycle differences which may account, in part, for the different quality of the female voice. Interpretation of results using this technique must take account of the patient's sex.