Lipoperoxidation as a measure of free radical injury in otitis media

Oral steroids for hearing loss associated with otitis media with effusion in children aged 2-8 years: the OSTRICH RCT

BACKGROUND

Children with hearing loss associated with otitis media with effusion (OME) are commonly managed through surgical intervention, hearing aids or watchful waiting. A safe, inexpensive, effective medical treatment would enhance treatment options. Small, poorly conducted trials have found a short-term benefit from oral steroids.

OBJECTIVE

To determine the clinical effectiveness and cost-effectiveness of a 7-day course of oral steroids in improving hearing at 5 weeks in children with persistent OME symptoms and current bilateral OME and hearing loss demonstrated by audiometry.

DESIGN

Double-blind, individually randomised, placebo-controlled trial.

SETTING

Ear, nose and throat outpatient or paediatric audiology and audiovestibular medicine clinics in Wales and England.

PARTICIPANTS

Children aged 2-8 years, with symptoms of hearing loss attributable to OME for at least 3 months, a diagnosis of bilateral OME made on the day of recruitment and audiometry-confirmed hearing loss.

INTERVENTIONS

A 7-day course of oral soluble prednisolone, as a single daily dose of 20 mg for children aged 2-5 years or 30 mg for 6- to 8-year-olds, or matched placebo.

MAIN OUTCOME MEASURES

Acceptable hearing at 5 weeks from randomisation. Secondary outcomes comprised acceptable hearing at 6 and 12 months, tympanometry, otoscopic findings, health-care consultations related to OME and other resource use, proportion of children who had ventilation tube (grommet) surgery at 6 and 12 months, adverse effects, symptoms, functional health status, health-related quality of life, short- and longer-term cost-effectiveness.

RESULTS

A total of 389 children were randomised. Satisfactory hearing at 5 weeks was achieved by 39.9% and 32.8% in the oral steroid and placebo groups, respectively (absolute difference of 7.1%, 95% confidence interval -2.8% to 16.8%; number needed to treat = 14). This difference was not statistically significant. The secondary outcomes were consistent with the picture of a small or no benefit, and we found no subgroups that achieved a meaningful benefit from oral steroids. The economic analysis showed that treatment with oral steroids was more expensive and accrued fewer quality-adjusted life-years than treatment as usual. However, the differences were small and not statistically significant, and the sensitivity analyses demonstrated large variation in the results.

CONCLUSIONS

OME in children with documented hearing loss and attributable symptoms for at least 3 months has a high rate of spontaneous resolution. Discussions about watchful waiting and other interventions will be enhanced by this evidence. The findings of this study suggest that any benefit from a short course of oral steroids for OME is likely to be small and of questionable clinical significance, and that the treatment is unlikely to be cost-effective and, therefore, their use cannot be recommended.

FUTURE WORK

Studies exploring optimal approaches to sharing natural history data and enhancing shared decision-making are needed for this condition.

TRIAL REGISTRATION

Current Controlled Trials ISRCTN49798431 and EudraCT 2012-005123-32.

FUNDING

This project was funded by the National Institute for Health Research (NIHR) Health Technology Assessment programme and will be published in full in Health Technology Assessment; Vol. 22, No. 61. See the NIHR Journals Library website for further project information.

Oral steroids for the resolution of otitis media with effusion (OME) in children (OSTRICH): study protocol for a randomised controlled trial

BACKGROUND

Otitis media with effusion (OME) is an accumulation of fluid in the middle ear affecting about 80 % of children by the age of 4 years. While OME usually resolves spontaneously, it can affect speech, behaviour and development. Children with persistent hearing loss associated with OME are usually offered hearing aids or insertion of ventilation tubes through the tympanic membrane. Oral steroids may be a safe and effective treatment for OME, which could be delivered in primary care. Treatment with oral steroids has the potential to benefit large numbers of children and reduce the burden of care on them and on health services. However, previous trials have either been too small with too short a follow-up period, or of too poor quality to give a definite answer. The aim of the Oral Steroids for the Resolution of Otitis Media with Effusion in Children (OSTRICH) trial is to determine if a short course of oral steroids improves the hearing of children with OME in the short and longer term.

METHODS/DESIGN

A total of 380 participants (children of 2 to 8 years of age) are recruited from Hospital Ear, Nose and Throat departments in Wales and England. A trained clinician seeks informed consent from parents of children with symptoms for at least 3 months that are attributable to OME and with confirmed bilateral hearing loss at study entry. Participants are randomised to a course of oral steroid or a matched placebo for 1 week. Outcomes include audiometry, tympanometry and otoscopy assessments; symptoms; adverse effects; functional health status; quality of life; resource use; and cost effectiveness. Participants are followed up at 5 weeks, and at 6 and 12 months after the day of randomisation. The primary outcome is audiometry-confirmed satisfactory hearing at 5 weeks.

DISCUSSION

An important evidence gap exists regarding the clinical and cost effectiveness of short courses of oral steroid treatment for OME. Identifying an effective, safe, nonsurgical intervention for OME in children for use in primary care would be of great benefit to children, their families and the NHS.

TRIAL REGISTRATION

ISRCTN

ISRCTN49798431 (Registered 7 December 2012).

Effect of Ginkgo leaf parenteral solution on blood and cochlea antioxidant and immunity indexes in OM rats

Oxidative stress is involved in the development and progression of otitis media (OM). In this study, we investigated the effect of Ginkgo leaf parenteral solution on blood and cochlea antioxidant and immunity indexs in OM rats. In OM model rats, blood and cochlea malondialdehyde (MDA), nitric oxide (NO), tumor necrosis factor-alpha (TNF-α), interleukin-1 beta (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8) and interleukin-10 (IL-10) levels were significantly increased, whereas antioxidant enzymes activities (superoxide dismutase (SOD), catalase (CAT), glutathione peroxidase (GSH-Px) and glutathione reductase (GR)) were significantly decreased compared with normal rats. Treatment with Ginkgo leaf parenteral solution restored the altered parameters in a dose-dependent manner. We conclude that Ginkgo leaf parenteral solution confers protection against oxidative injuries in OM rats by increasing activities of antioxidants and immunity, suggesting a potential drug for the prevention and therapy of OM.

Oxidant and antioxidant levels in children with acute otitis media and tonsillitis: a comparative study

OBJECTIVE

Recurrent episodes of acute otitis media (AOM) and acute tonsillitis (AT) are a common problem in infectious disorders during childhood and are major cause of morbidity in children. The organism maintains defense systems including nonenzymatic antioxidants such as Vitamins A, E and C and reduced glutathione (GSH) against reactive oxygen species (ROS). In the present study, lipid peroxidation status and nonenzymatic antioxidant capacity were investigated in children with AOM and AT. Our aim was to compare the lipid peroxidation and responses of the body's antioxidant status in the closely associated infections such as AOM and acute tonsillitis.

METHODS

The study included 23 (14 males, 9 females) children with AOM, 27 (14 males, 13 females) with AT and 29 (16 males, 13 females) healthy control subjects. The ages of the study and control subjects were between 2 and 7 years. Serum beta-carotene, retinol, Vitamin E, Vitamin C, and whole blood malondialdehyde (MDA) (as an indicator of lipid peroxidation) and GSH levels were studied in all subjects.

RESULTS

There was a statistically significant difference between the groups for all parameters (P<0.05). All of the antioxidant vitamins such as beta-carotene, retinol, Vitamin E, and Vitamin C levels were observed to be significantly decreased in the both patient groups. Nevertheless, GSH levels were also decreased in the patient groups. MDA levels were found to be higher in children with AOM and AT than in the healthy control subjects. When compared the AOM and AT groups, there was statistically significant difference between the groups for whole blood MDA (P<0.05).

CONCLUSION

Even though they seem to react in a similar way against ROS, in the cases of AOM and AT, it is possible to see the different approaches in these tissues for the oxidative stress.

Nutritional Supplements and Upper Respiratory Tract Illnesses in Young Children in the United States

Key Points

In the United States, children have lower blood levels than adults of eicosapentaenoic acid (EPA), an important ω-3 fatty acid that helps decrease inflammation; vitamin A, the “anti-infective” vitamin; and selenium (Se), a trace metal that is an intrinsic part of glutathione peroxidase, an important free-radical scavenging enzyme.

EPA, vitamin A, and Se are important in controlling inflammation and can be supplied by oral nutritional supplements.

Cod liver oil contains EPA (and other important ω-3 fatty acids), and vitamin A as well as vitamin D.

Fish oil contains ω-3 fatty acids (including EPA) but no vitamins.

Our clinical research demonstrates that daily supplementation with a flavored cod liver oil (which meets European purity standards) and a children’s multivitamin-mineral with trace metals, including Se, can decrease morbidity from upper respiratory tract illnesses, otitis media, and sinusitis in young children living in the United States.

These supplements can be used by practitioners on an individual basis, when clinically indicated; the supplements can be purchased in the United States without a prescription.

Socioeconomically disadvantaged children are at risk for micronutrient deficiencies. However, their families may not be able to afford to purchase these supplements, which are not available through Medicaid, The Special Supplemental Nutrition Program for Women, Infants and Children, or the Food Stamp Program.

If our results are confirmed in larger studies, a system change will be needed to provide these supplements to nutritionally vulnerable, socioeconomically disadvantaged children living in the United States.

Determination of Reactive Oxygen Species in Myringotomized Tympanic Membranes: Effect of Vitamin E Treatment

OBJECTIVES/HYPOTHESIS

Recent studies have established a strong relationship between the development of myringosclerosis and reactive oxygen species (ROS). The aims of the present study were to directly detect ROS in the tympanic membrane and middle ear mucosa of rats by measuring luminol amplified chemiluminescence, to evaluate the changes in the levels of ROS after treatment with vitamin E, and to examine the possible changes in the tympanic membranes otomicroscopically and histologically.

STUDY DESIGN

Prospective controlled animal study.

METHODS

Forty healthy Sprague-Dawley rats were divided into five groups of eight animals each. Animals in all groups except group 1 were bilaterally myringotomized. Group 2 received no treatment, group 3 was treated with topical olive oil, group 4 received topical vitamin E, and group 5 received intramuscular vitamin E. After 24 hours of myringotomy, tympanic membranes were examined otomicroscopically; thereafter, tympanic membranes and middle ear mucosa were peeled off. The right ears of the animals were used for biochemical assay, and the left ears were used for histological study.

RESULTS

Reactive oxygen species levels were significantly decreased in group 4 with topical application of vitamin E compared with untreated and myringotomized animals in group 2. Reactive oxygen species levels were also decreased in group 5, although the decrease was not statistically significant when compared with groups 2 and 3. Histological studies confirmed sclerotic changes in the untreated myringotomized animals. The tympanic membranes of animals in groups 2 and 3 showed a white, chalk-like pattern of sclerotic changes, whereas animals in groups 4 and 5, with the exception of two animals in group 5, lacked these changes.

CONCLUSION

Although the relationship between the development of myringosclerosis and ROS had been well documented previously, the present study is the first that has directly measured the levels of ROS in the tympanic membrane and middle ear mucosa. These results are relevant because they correlate with histological findings. It has also been demonstrated that topically applied vitamin E is effective in decreasing the ROS levels.

Lemon-flavored cod liver oil and a multivitamin-mineral supplement for the secondary prevention of otitis media in young children: pilot research

We measured blood levels of fatty acids, vitamin A, and trace metals in children undergoing ambulatory surgery for placement of tympanostomy tubes and a comparison group having other ambulatory surgical procedures. We then performed a small, outpatient, secondary prevention study using nutritional supplements chosen on the basis of those blood levels. The study subjects had lower levels of red blood cell eicosapentaenoic acid (EPA) than did adult controls. Consistent with previous reports, the levels of vitamin A were < or = 40 microg/dL for 69% of our subjects, and the plasma selenium levels for children were lower than published values for adults. We then studied one otitis media (OM) season; 8 children (0.8 to 4.4 years of age) received 1 teaspoon of lemon-flavored cod liver oil (containing both EPA and vitamin A) and 1 half-tablet of a selenium-containing children's chewable multivitamin-mineral tablet per day. During this OM season, study subjects received antibiotics for OM for 12.3% +/- 13.4% (SD; p < .05) fewer days during supplementation than before supplementation. Larger, controlled trials are warranted to assess the utility of cod liver oil (of acceptable purity and taste) and a children's multivitamin-mineral preparation containing selenium, both for the prevention of OM and for the acceptance of delayed prescription of antibiotics for this disorder.

The effect of local administration of N-acetylcysteine in perforated rat tympanic membrane: an experimental study in myringosclerosis

Myringosclerosis (MyS) is a common sequela of acute and chronic otitis media and ventilation tube treatment of serous otitis media. We aimed to study the effect of topical administration of N -acetylcysteine (NAC) on MyS by assessment of otomicroscopic evaluation, lipid peroxidation and nitric oxide (NO) (nitrite/nitrate) levels in experimental myringotomized rat tympanic membrane. Thirty adult rats were used and the upper posterior quadrant of the tympanic membranes of rats was myringotomized. Thereafter, they were divided into four groups. Group I received no treatment, group II was treated with saline, groups III and IV were treated with topical NAC (0.1 ml of 6 and 12 mg ml(-1), respectively). The levels of nitrite/nitrate and malondialdehyde (MDA) were measured in serum samples. In the otomicroscopic evaluation, non-treated and saline treated ears (controls) showed extensive occurrence of myringosclerotic plaques. Groups III and IV showed fewer occurrences of sclerotic plaques. There was no significant difference between groups III and IV regarding the development of MyS. The development of myringosclerotic lesion was found to be significantly different between NAC treated groups (III and IV) and the control groups (I and II). The levels of nitrite/nitrate of both groups III and IV were significantly lower than the control groups. The levels of MDA of these groups were also significantly lower than the control group. The relationship between groups III and IV was not statistically significant for the levels of nitrite/nitrate and MDA. We conclude that the topical treatment of NAC reduces the levels of MDA and NO products in rats. These results suggest that topical NAC application may be useful for the prevention of MyS.

Management of chronic otitis media with effusion: the role of glutathione

BACKGROUND

The inflammatory cells documented in chronic otitis media with effusion (OME) spontaneously release oxidants which can induce middle ear (ME) epithelial cell damage. Glutathione (GSH), a major extracellular antioxidant in humans, plays a central role in antioxidant defense.

PURPOSE

To evaluate the effects of GSH treatment on chronic otitis media with effusion (OME).

SUBJECTS AND INTERVENTION

Sixty children with chronic OME were enrolled, 30 of whom were randomly assigned to the treatment group and 30 to the placebo group. Patients in the treatment group received 600 mg glutathione in 4 mL saline per day subdivided into five 2-minute administrations given by nasal aerosol every 3 or 4 waking hours for 2 weeks. Patients in the control group received 4 mL saline per day following the same procedure as for GSH treatment.

RESULTS

Three months after therapy improvement had occurred in 66.6% of patients in the GSH-treated group and in 8% of the control subjects (P <.01).

CONCLUSION

On the basis of these results, GSH treatment could be considered for the nonsurgical management of chronic OME.

Can Eustachian Tube Ventilatory Function Impairment After Oxygen Diving Be Influenced by Application of Free Radical Scavenger Vitamins C and E?

OBJECTIVES/HYPOTHESIS

To evaluate the influence of free radical scavenger vitamins C and E on eustachian tube ventilatory function changes related to oxygen dives.

STUDY DESIGN

Prospective, randomized, double-blind, placebo-controlled study of middle ear impedance changes of oxygen divers being orally treated with free radical scavenger vitamins C and E.

METHODS

Fifteen divers were allocated to two groups. Before diving on oxygen on consecutive days (days 1 and 2), divers in group 1 took a daily dose of 1 g ascorbic acid and 600 International Units d-alpha-tocopherol and divers in group 2 were given placebo. Before diving and 2 and 24 hours after diving on days 1 and 2, middle ear impedance was measured.

RESULTS

Impedance decreased overnight after dive 1 (P =.04) but not after dive 2 (P =.31). No impedance differences were found between groups after the dive on day 1 (P =.83). Twenty-four hours after the dive on day 1 and after the dive on day 2, impedance values in both groups were different (P =.02 vs. P =.07), emphasizing slightly more negative pressures in the vitamin group.

CONCLUSION

Vitamins C and E did not reduce eustachian tube ventilatory function impairment overnight after the dive on day 1, suggesting no evidence of free radical-mediated toxicity affecting the eustachian tube or middle ear mucosa. Repetitive oxygen dives may cause tissue adaptation suggesting other than antioxidant defense mechanisms.

Free radical production by antibiotic-killed bacteria in the guinea pig middle ear

OBJECTIVES

Oxygen free radicals are implicated in the pathogenesis of otitis media Recent investigations with animal models have demonstrated that free radical-mediated damage of the middle ear mucosa, measured as lipid hydroperoxide, occurs when the middle ear cavity is inoculated with Streptococcus pneumoniae. The present study was conducted to examine the effect of antibiotics on free radical-mediated damage in pneumococcal acute otitis media.

STUDY DESIGN

Animal model of acute otitis media.

METHODS

Seventy-eight guinea pigs underwent bilateral middle ear inoculation with 100 microl of 1) sterile saline as a control, 2) 50 microg/mL amoxicillin, 3) 10(7) colony forming units (CFU)/mL Streptococcus pneumoniae killed with 50 microg/mL amoxicillin, or 4) 10(7) CFU/mL S. pneumoniae. Animals were killed on postoperative day 1 or 5, and the middle ear mucosa was examined for lipid peroxidation as evidence of free radical damage.

RESULTS

Mucosal lipid hydroperoxide was significantly elevated compared with control subjects on day 1 in both the antibiotic-killed S. pneumoniae group and the S. pneumoniae-infected group. On day 5, the S. pneumoniae-infected mucosa had significantly higher lipid hydroperoxide levels compared with the antibiotic-killed group and the control subjects. Histological studies confirmed mucosal edema and the presence of inflammatory cells in the infected groups.

CONCLUSIONS

Antibiotic-killed bacteria seem to produce free radical-mediated damage to the middle ear mucosa in the early phase of acute otitis media. The clinical implication of this study is that free radical damage to the middle ear mucosa may occur in otitis media despite appropriate antibiotic therapy.

Evidence of oxygen free radical damage in human otitis media

Recent work with a guinea pig model of otitis media has demonstrated evidence of oxygen free radical damage to the middle ear mucosa. However, the relevance of an animal model to human disease is uncertain. Accordingly, the following pilot study was conducted to examine human middle ear fluid for lipid hydroperoxides as evidence of free radical damage. Thirty-five specimens of middle ear fluid from children with chronic otitis media were collected and described as mucoid (n = 19), purulent (n = 10), or serous (n = 6); specimens were weighed and analyzed for lipid hydroperoxide content. The results demonstrated the presence of lipid hydroperoxide in all 3 types of middle ear fluid. Additionally, there was a statistically significant elevation of total lipid hydroperoxide content in mucoid effusions compared with serous effusions, as well as a significant elevation of lipid hydroperoxide divided by weight of purulent effusions compared with serous effusions. This is the first study to document free radical damage in human otitis media.