Quantitative determination of bacterial endotoxin in middle ear effusions by chromogenic substrate method

Assessment of Pediatric Middle Ear Effusions With Wideband Tympanometry

OBJECTIVE

To determine if wideband tympanometry (WBT) can differentiate types of middle ear effusion (MEE): serous, mucoid, and purulent.

STUDY DESIGN

Prospective cohort study.

SETTING

Tertiary care children's hospital.

METHODS

Children who met American Academy of Otolaryngology-Head and Neck Surgery's guidelines for ventilation tube insertion had WBT after anesthesia induction but before tympanotomy. MEE was categorized into 1 of 4 comparison groups: serous effusion, mucoid effusion, purulent effusion, or no effusion. WBT measurements were averaged to 16 one-third octave frequency bands, and comparison of the absorbance patterns for each MEE type was performed through a linear mixed effects model.

RESULTS

A total of 118 children (211 ears) were included: 47 females (39.8%) and 71 males (60.2%). The mean age was 2.73 years (95% CI, 2.25-3.22); mean weight, 14.35 kg (95% CI, 12.85-15.85); and mean Z score, 1.13 (95% CI, -0.64 to 2.33). Effusions included 61 mucoid (28.9%), 30 purulent (14.2%), and 14 serous (6.6%), with 106 (50.2%) having no effusion. No significant differences were found for sex, race, age, weight, or Z score among the 4 types of effusion (P < .05). WBT showed a significant difference in median absorption among the effusion groups (P < .001), with a medium effect size of 0.35.

CONCLUSIONS

WBT has potential use to differentiate types of MEE and should be studied further as a tool for investigating how the natural history and management of serous and mucoid effusions may differ.

Longitudinal results of intratympanic injection of budesonide for otitis media with effusion in children over 12 years and adults

OBJECTIVE

To assess the longitudinal curative effect and improvement of subjective symptoms by using intratympanic injection of Budesonide(BUD) for otitis media with effusion (OME) patients older than 12 years and adults.

STUDY DESIGN

A single-blind, randomized, parallel-controlled prospective study.

SETTING

Hospital, outpatient.

PATIENTS

Ninety patients (112 ears) who were diagnosed as having OME were recruited and then randomized to BUD, dexamethasone (DEX), and sodium chloride (NS) groups, the latter two served as controls.

INTERVENTIONS

The randomly allocated patients received intratympanic injection of BUD (0.5 mg/1 ml), DEX (2 mg/1 ml), or 0.9% NS solution (1 ml) once a week.

MAIN OUTCOME MEASURES

Survival analysis was applied to compare the longitudinal curative effects among the 3 groups. Meanwhile, the 6 main subjective symptoms were scored by 10-point visual scale, and physician's evaluations were preformed during treatment and follow-up.

RESULTS

After adjustment for course of disease, volume, and characters of effusion, the relative risk (RR) of BUD is 0.139 (95% CI, 0.054-0.358) when compared with NS. Survival curve demonstrated that the rank of longitudinal therapeutic efficacy was BUD, DEX, and NS (p < 0.05). Both BUD and DEX showed improvements in subjective symptoms and quality of life compared with NS (p < 0.05). In the aspect of improving the symptom of stuffy ear, BUD showed advantage over both DEX and NS. During and after treatment, no serious complications or sequelae were observed.

CONCLUSION

Intratympanic injection with BUD for OME patients showed advantages in improving long-term therapeutic efficacy, it was a safe and effective intervention for adolescents and adults with OME.

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.

New Aspects of Secretory Otitis Media, Eustachian Tube Function and Middle Ear Gas

The insertion of ventilation tubes to equalize pressure in the middle ear is the most common procedure used to treat otitis media. This article evaluates the advantages and drawbacks of ventilation and explores the various roles of the components of middle ear pressure, with special emphasis on oxygen-derived free radicals.

Effect of HA-1A monoclonal IgM antibody on endotoxin-induced proliferation of cultured rat middle ear epithelium

The effect of human monoclonal antibody HA-1A (Centoxin) on the effect of endotoxin on cultured rat middle ear epithelium was investigated. The addition of endotoxin to the standard culture medium revealed a concentration-related proliferative effect on cultured rat middle ear epithelium, leading to cobblestone cells, cell tracks, and stratification of epithelium, whereas rat middle ear epithelium cultured in standard medium grew as a monolayer composed of flat polygonal cells. Addition of HA-1A to standard medium supplemented with endotoxin gave rise to a statistically significant suppression of the proliferative effects of endotoxin on these cells. The morphology of rat middle ear epithelium cultured in the presence of HA-1A and endotoxin showed that these cells still had a tendency to form cobblestone-like cells and cell tracks, but to a substantially lower degree. The present results support the hypothesis that HA-1A suppresses the proliferative and morphological effects of endotoxin on rat middle ear epithelium and may play an important role in the pathogenesis of otitis media.

Effects of human middle ear effusions on the mucociliary system of the tubotympanum in the guinea pig

Effusion fluid resulting from otitis media contains a variety of inflammatory substances. This middle ear effusion (MEE) may be itself affect the mucosa of the tubotympanum and contribute to chronicity of the condition. The present study was designed to elucidate in vitro and in vivo effects of MEEs on the mucosa of the guinea pig tubotympanum. The results obtained demonstrated that the ciliary activity of the eustachian tube was reduced in the presence of human MEEs. This activity decreased to approximately 80% in the presence of serous MEE at 48 h and was 60% after exposure to mucoid MEE. Intratympanic inoculation of human MEEs resulted in accumulation of a serous effusion in the tympanic cavity. Histologic study of the tubotympanum in inoculated animals demonstrated mucociliary dysfunction as well as a general inflammatory process and increased vascular permeability. This damage was more prominent following inoculation with the mucoid MEEs. The ciliary depression and inflammation found in the tubotympanum suggest that the pathologic nature of MEEs may be, at least partially, responsible for the chronicity of otitis media.

The influence of endotoxin upon middle ear fibroblasts cultured in normal middle ear gas and atmospheric air

Otitis media represents a continuum of inflammatory stages frequently in association with bacteria and/or endotoxin. Furthermore, the disease is often treated with insertion of ventilation tubes, which causes hyperoxia relative to the physiological state in the tympanic cavity. The present study was undertaken to quantitate the interaction between endotoxin and relative hyperoxia in cultures of rabbit middle ear fibroblasts incubated in normal middle ear gas and atmospheric air, respectively. Growth was monitored by determination of DNA, cell protein and cell division. The synthetic activity was estimated by collagen production. The antioxidant defense was determined by measuring the intra-and extracellular concentrations of superoxide dismutase (SOD). The results demonstrated that hyperoxia significantly impaired the growth of middle ear fibroblasts, which was compensated for by addition of endotoxin stimulating the growth. The collagen synthesis increased significantly in atmospheric air with a synergistic effect of endotoxin. Hyperoxia induced intracellular SOD formation, while endotoxin tended to reduce the synthesis. Finally, exposure to atmospheric air caused significantly larger amounts of reducing agents extracellularly in cultures without endotoxin compared to endotoxin incubated cultures. It is suggested that endotoxin possess both synergistic and antagonistic potential as regards the effects of relative hyperoxia, and that the interaction between endotoxin and hyperoxia may be an important factor in otitis media.

Clinical efficacy of Tranilast on otitis media with effusion in children

In this open randomized study, we evaluated the efficacy of Tranilast, one of the anti-inflammatory drugs, on otitis media with effusion in children. Sixty-two patients (103 ears) were divided into two groups: Group A was given Tranilast and local treatment (nasal and tubal); Group B only received local treatment (control for Group A). The overall improvement rating assessed as "moderately improved or above" for Group A was 63.6%, Group B 47.9%. There was a significant improvement in Group A as compared to Group B (p < 0.05). In subjects who suffered from otitis media with effusion for over 2 months. Group A exhibited 50.0% of efficacy while Group B only 15.4% (p < 0.05).

Bacteria and endotoxin in middle ear fluid and the course of secretory otitis media

To determine the influence of bacteria and bacterial products on the course of secretory otitis media (SOM) following ventilation tube insertion we examined 68 middle ear effusions from 57 children with SOM. Swabs were taken for bacteriological examination and the content of endotoxin was measured. The children were followed up for one year and relapse of SOM was recorded. Bacteria were present in 38% of effusions and endotoxin was detectable in 96%. Relapse occurred in 26% of the patients and was related to the presence of bacteria in the original effusion (P < 0.01). The concentration of endotoxin, however, did not correlate with the course of SOM.

Effect of endotoxin on cultured chinchilla middle ear epithelium

The effect of endotoxin on the growth and morphology of cultured chinchilla middle ear epithelium was examined. Within 24 hours of culture, cells maintained in medium containing endotoxin exhibited dose-dependent morphological changes. The highest concentration of endotoxin (100 mg) resulted in cell death. The growth curve of the cells in culture demonstrated a dose-dependent, significant increase in cell number when endotoxin was added to the medium.

Effects of bacterial endotoxin on the ciliary activity in the in vitro eustachian tube

We have used a tissue culture technique and a photoelectric method to examine the direct effect of lipopolysaccharide (LPS) on the ciliary activity present in the eustachian tube. Since LPS possesses the major part of the biological activity of endotoxin, our results show clearly that LPS deteriorates the ciliary activity in a dose-response fashion: LPS does not deteriorate the ciliary activity up to 168 h if its concentration is 1 ng/ml or less; 10 ng/ml LPS can cause deterioration of the ciliary activity with extended exposure (more than 96 h); LPS can cause dysfunction of the cilia rather quickly if the concentration is 100 ng/ml or more. Our results show that the ciliary activity in the eustachian tube under clinical conditions can be affected by endotoxin.