Occurrence and recurrence of acute otitis media among children

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

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

Otoscopic and audiological findings in different populations of 5-14 year-old schoolchildren in Colombia

OBJECTIVE

To present the otoscopic and audiological findings of studies carried out in groups of 5-14 year old schoolchildren in diverse indigenous, White, and African descended communities in the Republic of Colombia.

MATERIALS AND METHODS

The present study is descriptive and cross-sectional. We obtained a convenience sample for the analysis. We define acute otitis media (AOM), (bulging or redness); tympanic perforation (TP), (disruption of continuity in the tympanic membrane) and sequelea (scarring, myringosclerosis, retractions, secrections). Our results are described as frequencies in percentages. Audiometry was performed in every student. Readings were taken at 250, 500, 1000, 2000, 4000, and 8000 Hz for air-conduction and bone-conduction thresholds. Normal hearing is considered up to 20 dB, mild sensorineural hearing loss between 21 and 39 dB, moderate between 40 and 59 dB, severe between 60 and 89 dB and profound more than 90 dB. For conductive hearing loss the air-bone gap is measured.

RESULTS

3052 otoscopies were conducted in 1526 schoolchildren. Males predominated in each group except in the Wayuu group. Otoscopic abnormalities rates varied between 1.5% in Providencia group, up to 9.6% in the Amazon groups. No perforations were found in the Wayuu Indian schoolchildren and the highest frequency of Tympanic perforations (1.2%) and sequelaes (8.2)% in the Amazon groups. Audiometric findings were normal in 94-98% of cases. Conductive hearing loss (CHL) was found in 5.5% of Amazon groups and the lowest (1.4%) in the Wayuu groups. Slight to moderate Neurosensorial Hearing Loss (NHL) were found in 1.3% in the Arhuaca communities and moderate 0.9% in the Amazon groups.

CONCLUSIONS

The present study is the first conducted in Colombia to evaluate the frequency of ear diseases and sequelae in populations of 5-14 year old children. High prevalences of sequelaes were found in the indigenous groups of the Amazon and the lowest in the Black schoolchildren on the island of Providencia. It is recommended that medical anthropological studies be conducted in these areas, and evaluation done on the probable connection between these types of diseases and processes of intercultural interaction.

Incidence of otitis media in a contemporary Danish National Birth Cohort

Objectives

In recent years welfare in Denmark has increased which might be expected to reduce otitis media (OM) incidence. We examined the age-specific incidence of OM in a nation-wide cohort of children aged 0–7 years born in 1996–2003 (Danish National Birth Cohort, DNBC). Only selection was ability to understand and speak Danish.

Methods

Information of OM and ventilation tubes (VT) was collected through three maternal interviews at 6-month, 18-month and 7-years of age and based on this age-specific and cumulative incidence of OM was calculated. As different numbers of the total population answered the different interviews, the calculations are done with different denominators. The information in DNBC was validated against two population based registries containing information of VT insertions.

Results

Cumulative incidence of OM at 7 years was 60.6% (31,982/52,755). For children with OM, 16.2% (7143/44194) had their first OM episodes between 0–6 months of age, 44.3% (19579/44194) between 7–18 months, and 39.5% (17472/44194) between 19 months and 7 years. Four or more OM episodes before 7 years were reported by 39.5% (12620/31982) and by 64.0% (2482/3881) of those who had their OM debut between 0–6 months; by 48.2% (4998/10378) with debut between 7–18 months; and by 28.7% (4996/17344) with debut between 19 months and 7 years. These figures are essentially unchanged from earlier figures from Denmark. VT insertion at least once was reported by 26,1% in the 7-year interview. Assuming recordings in the Danish National Patient Registry to be gold standard, maternal self-reportings in DNBC of insertion of VT showed high sensitivity (96.4%), specificity (98.2%), and positive (94.8%) and negative predictive values (98.8%).

Conclusion

OM affects nearly 2/3 of preschool children in Denmark despite reduction in known OM risk factors.

Panel 1: Epidemiology, natural history, and risk factors

BACKGROUND

The First International Symposium on Recent Advances in Otitis Media (OM) with Effusion was held in Columbus, Ohio, in 1975. The symposium has been organized in the United States every 4 years since, followed by a research conference to (a) assess major research accomplishments, (b) identify important research questions and opportunities, (c) develop consensus on definitions and terminology, and (d) establish priorities with short- and long-term research goals. One of the principal areas reviewed quadrennially is Epidemiology, Natural History, and Risk Factors.

OBJECTIVE

To provide a review of recent literature on the epidemiology, natural history, and risk factors for OM.

DATA SOURCES AND REVIEW METHODS

A search of OM articles in English published July 2007 to June 2011 was conducted using PubMed and related databases. Those with findings judged of importance for epidemiology, public health, and/or statistical methods were reviewed.

RESULTS

The literature has continued to expand, increasing understanding of the worldwide burden of OM in childhood, complications from treatment failures, and comorbidities. Novel risk factors, including genetic factors, have been examined for OM susceptibility. Population-based studies in Canada, the United States, and other countries confirmed reductions in OM prevalence. Although most studies concentrated on acute OM (AOM) or OM with effusion (OME), a few examined severe chronic suppurative OM (CSOM), a major public health problem in developing countries and for certain indigenous populations around the world.

CONCLUSIONS AND IMPLICATIONS FOR PRACTICE

Recent publications have reinforced earlier epidemiological findings, while extending our knowledge in human population groups with high burden of OM.

The importance of right otitis media in childhood language disorders

Studies relating chronic otitis media and language disorders in children have not reported consistent findings. We carried out the first selective study aimed at discerning the role of chronic right otitis media in children less than 3 years of age in language development. A total of 35 children were studied using a full linguistic protocol, auditory brainstem responses, and middle latency responses. Twelve children had a history of chronic exclusive right otitis media. Seventeen age-matched children were selected as controls. Also, three children having a history of chronic left otitis media were compared with three age-matched controls. Linguistic tests showed significant differences between patients and controls in phonetic, phonological, and syntax scores but not semantics. Correlation studies between linguistic scores and auditory evoked responses in the whole cohort showed a significant coefficient in phonetic and phonological domains. These results emphasize the causative effect of right ear chronic otitis media and indicate that it mainly impairs phonetic and phonological coding of sounds, which may have implications for prophylactic treatment of at-risk children.

Acute otitis media in neonatal life: a review

Acute otitis media is frequently encountered by general practitioners and pediatricians. In the neonatal period acute otitis media may present as an isolated local infection or as part of septicemia. Diagnosis of the condition by otoscopy is difficult. Considering the wide spectrum of middle ear disorders (acute otitis media, otitis media with effusion, chronic suppurative otitis media) one can appreciate why opinions on the management of the condition are diverse. This is a review of the literature on clinical presentation, etiology, risk factors, treatment and prevention of acute otitis media in neonatal life.

Mastoiditis in a paediatric population: a review of 11 years experience in management

OBJECTIVE

This study explores the experience at Sydney Children's Hospital (SCH) managing children with acute mastoiditis and establishes a robust treatment algorithm.

METHODS

Retrospective review of all patients admitted to SCH with an ICD-10 coding of "Mastoiditis" from 1 January 1996 through 31 December 2006 inclusive. Criteria assessed included demographic characteristics, clinical features, symptom duration and treatment initiated by the general practitioner. The results of investigations at SCH were reviewed including white blood cell count, microbiology and imaging. The presence of complications was determined and the results of medical and surgical treatment were assessed.

RESULTS

Seventy-nine episodes of acute mastoiditis were managed in 76 patients. Treatment prior to SCH was commenced by the family practitioner or district hospital doctor in 53/79 patients. The mean duration of community initiated treatment before presentation to SCH was 3.7 days. In 33 episodes a previous history of acute otitis media was noted (42%). In the remaining 46 episodes (58%) mastoiditis was the initial diagnosis. Complications were found in 30 episodes (38%) and 36 episodes (46%) required surgical treatment.

CONCLUSIONS

Mastoiditis often develops rapidly but may be treated very effectively. The potential for significant morbidity remains high but excellent outcomes can be expected for those who are managed without delay. Children with acute mastoiditis should be managed in centres where timely and complete medical and surgical treatment is available.

Effects of cigarette smoking on mucin production in human middle ear epithelial cells

OBJECTIVE

Otitis media (OM) is the most common disease in preschool age children related to passive cigarette smoking as risk factor. In this study, we investigate whether the cigarette smoking can induce the inflammation in human middle ear epithelial cell, and cigarette smoke-induced inflammation can increase the expression of MUC5AC gene and protein that was known to play an important role in OM with effusion.

METHODS

After treatment of cigarette smoke solution (CSS) on immortalized human middle ear epithelial cells (HMEECs) with or without pretreatment by epidermal growth factor receptor (EGFR) tyrosine kinase inhibitor (AG1478), we observed expression of tumor necrosis factor-alpha (TNF-α), EGFR, MUC5AC mRNA by quantitative real-time reverse transcriptase-polymerase chain reaction (RT-PCR) and EGFR, MUC5AC protein by western blotting.

RESULTS

Treatment of CSS increased expression of TNF-α mRNA dose dependently. Treatment of CSS upregulated the EGFR and MUC5AC mRNA in a time-dependent manner. CSS-induced upregulation of EGFR and MUC5AC mRNA was suppressed by the pretreatment of AG1478. EGFR and MUC5AC proteins were upregulated by the treatment of CSS and suppressed by the pretreatment of AG1478.

CONCLUSIONS

Treatment of CSS on HMEECs increased the expression of MUC5AC mRNAs and proteins which play a major role in OM with effusion.

Drugs in upper respiratory tract infections in paediatric patients in North Trinidad

OBJECTIVE

We explored the prescribing patterns of physicians in North Trinidad in treating upper respiratory tract infections (URTI) in paediatric patients and the appropriateness of drugs prescribed.

METHODS

A retrospective observational study was conducted, with a sample size of 523 paediatric patients, diagnosed with an URTI during the period of June 2003 to 22 June 2005. The study was conducted at five Primary Health Care Facilities in North Trinidad.

RESULTS

The three most frequent URTIs diagnosed were non-specific URTI, common cold, and acute tonsillitis in rank order. Four patterns of prescribing were identified, (1) no drug therapy [1.9%]; (2) antibiotic therapy alone [6.1%]; (3) antibiotic and symptomatic therapy [53.0%]; and (4) symptomatic therapy alone [39.0%]. The, most frequently prescribed antibiotics were penicillins (amoxicillin [46.3%] and amoxicillin/clavulanate [5.3%]) and a macrolide (erythromycin [6.1%]). The three symptomatic agents most frequently prescribed were paracetamol [40.1%]; diphenhydramine [29.1%]; and normal saline nasal drops [14.2%]. In 112 cases with swab analyses done, of these, 98.2% revealed a growth of commensals only, while 1.8% grew pathogenic micro-organisms. Of the cases showing commensal growth only, 84.6% were treated with an antibiotic, 14.5% were treated with symptomatic agents alone and 0.9% received no drug therapy at all.

CONCLUSIONS

A large proportion of paediatric patients diagnosed with an URTI in North Trinidad was prescribed antibiotics although not indicated The inappropriate use of antibiotics can potentiate the worldwide trend of antimicrobial resistance.

Prevalence and risk factors of otitis media with effusion in Trabzon, a city in northeastern Turkey, with an emphasis on the recommendation of OME screening

This cross-sectional study was undertaken to assess the prevalence and risk factors for otitis media with effusion (OME) in Trabzon, a city in northeastern Turkey, and evaluate the need for screening for OME in the normal population. In kindergartens, daycare centers, public and private schools in the rural and central areas of Trabzon, 1,077 children aged between 5 and 12 years were examined. OME prevalence was 11.14% (120/1,077). Young age, attendance at kindergarten/daycare, low economical status, the mother's working status (housewife), history of snoring and acute otitis media, antibiotic use in the previous 3 months and active upper respiratory tract infection (URTI) were found to be the risk factors for OME. A history of hearing loss reported by the parents and teachers was found significant in the diagnosis of OME despite the low predictive value. When the parents suspected that their child had experienced hearing loss (in 36 cases), they did not refer them to a healthcare facility. To conclude, the approach to OME in developing countries should be more interventional as healthcare coverage is usually low and behavioral factors such as the demand for healthcare is poor.

Antibody levels after regular childhood vaccinations in the immunological screening of children with recurrent otitis media

Recurrent otitis media may be related to defects in specific antibody production, as suggested previously. This might be reflected in lower antibody responses to vaccinations administered in the context of the national childhood vaccination program in children suffering from recurrent otitis media. In a cross-sectional study we determined the levels of antidiphtheria, antitetanus, anti- Haemophilus influenzae type b (anti-Hib) and antimeasles antibodies in sera of 163 children with two or more episodes of acute otitis media per year and in 143 children with repeated periods of persistent otitis media with effusion each lasting at least 3 months. The control group consisted of 521 age-matched healthy children, who were free of recurrent respiratory tract infections. Children with recurrent acute otitis media, including highly otitis-prone children, showed higher antidiphtheria and antitetanus antibody titers compared to controls. No differences were observed in anti-Hib and antimeasles antibody levels between children with recurrent acute otitis media and controls, nor did any of the antibody levels in children with persistent otitis media with effusion differ from those in controls. Therefore, the results of our study do not point toward a generalized immunological hyporesponsiveness in children with recurrent acute otitis media and persistent otitis media with effusion. Determination of antibody responses to regular vaccines is not indicative for otitis-proneness.

Acute otitis media and season of birth

INTRODUCTION

This study examines the question whether season of birth is associated with acute otitis media (AOM) and recurrent AOM (rAOM) and whether season of birth is associated with early age of AOM onset.

METHODS

This was done in a population-based survey of 591 unselected Greenlandic children aged 3-5 and 8 years, living in the two largest towns in Greenland. The overall attendance rate was 86%. Information of AOM episodes was obtained from the parents and cross-checked in medical records available for 95% of the children. In total, 67% reported AOM at least once and 30% of those had rAOM.

RESULTS

According to season of birth, the frequency of history of AOM in general varied between 63% and 70% lowest for birth in the autumn and highest for birth in the spring but without any significant statistical difference (p=0.51). The similar variation in rAOM according to season of birth was between 21% and 35%, highest for children born in autumn and winter and lowest for children born in the spring (p=0.09). Additionally, there was no difference in age at onset of the first AOM episode according to season of birth. However, AOM children born in the summer and autumn periods have a significantly higher relative risk (RR=1.44, CI=1.04-1.99) of attracting rAOM than AOM children born in the winter and spring periods. This may be due to a higher risk of being quickly reinfected in the late autumn and winter period with another episode of upper respiratory tract infection.

CONCLUSION

Season of birth do not seem to be a predictor of AOM episodes or early onset of AOM but children born in the summer and autumn periods who attracts AOM have a higher risk of developing rAOM.

The epidemiology of acute bullous myringitis and its relationship to recurrent acute otitis media in children less than 2 years of age

OBJECTIVE

To evaluate the epidemiological characteristics of acute bullous myringitis (BM), i.e. inflammation of the tympanic membrane with blister(s) in children <2 years and study the relationship between bullous myringitis and recurrent acute otitis media.

METHODS

2028 children aged 7-24 months in a prospective longitudinal cohort study in the Finnish Otitis Media vaccine trial. The main outcome measures were the incidence of bullous myringitis and the incidence of acute otitis media (AOM) before and after the event of bullous myringitis.

RESULTS

82 children had a total of 86 events of acute bullous myringitis. The incidence of bullous myringitis was 5.7 per 100 person years (95% CI, 4.6-7.1 per 100 person years). The number of events with bullous myringitis was 4.6% of the number of all AOM events diagnosed during the follow-up. Recurrent AOM (> or =6 AOM events) occurred in 33% of children with bullous myringitis in comparison with 23% of control children with at least one event of AOM (RR 1.7; 95% CI, 1.01-2.7). The incidence of AOM in children with bullous myringitis was 1.8 per person year (95% CI, 1.4-2.2 per person year) before the event of bullous myringitis and 2.9 per person year (95% CI, 2.3-3.5 per person year) after the event of bullous myringitis. The higher incidence rate of AOM lasted for 2 months after the office visit of bullous myringitis.

CONCLUSIONS

Acute bullous myringitis is not a rare disease; it was diagnosed in 5.7% of children <2 years in a 1-year follow-up. It was present in almost 1 of every 20 AOM events. Acute bullous myringitis increases the subsequent risk of recurrent AOM.

Importance of respiratory viruses in acute otitis media

Acute otitis media is usually considered a simple bacterial infection that is treated with antibiotics. However, ample evidence derived from studies ranging from animal experiments to extensive clinical trials supports a crucial role for respiratory viruses in the etiology and pathogenesis of acute otitis media. Viral infection of the upper respiratory mucosa initiates the whole cascade of events that finally leads to the development of acute otitis media as a complication. The pathogenesis of acute otitis media involves a complex interplay between viruses, bacteria, and the host's inflammatory response. In a substantial number of children, viruses can be found in the middle-ear fluid either alone or together with bacteria, and recent studies indicate that at least some viruses actively invade the middle ear. Viruses appear to enhance the inflammatory process in the middle ear, and they may significantly impair the resolution of otitis media. Prevention of the predisposing viral infection by vaccination against the major viruses would probably be the most effective way to prevent acute otitis media. Alternatively, early treatment of the viral infection with specific antiviral agents would also be effective in reducing the occurrence of acute otitis media.

The association between iron-deficiency anemia and recurrent acute otitis media

PURPOSE

This study was designed to examine the association between iron-deficiency anemia and the frequency of recurrent acute otitis media in children, and to evaluate the effect of restoring normal hemoglobin levels on the frequency of acute otitis media attacks.

MATERIALS AND METHODS

A total of 680 children with frequent episodes of acute otitis media were enrolled in the study. The levels of the hemoglobin were measured in both these children and in 200 healthy children with no history of infections. The correlation between hemoglobin level and the frequency of middle ear infections was studied and analyzed. All children with hemoglobin levels lower than 9.5 g/dL received iron supplementation until they reached a level of at least 11 g/dL, and the subsequent frequency of middle ear infections was recorded.

RESULTS

The 680 children had an average of 8.3 +/- 2.7 episodes of acute otitis media per year per child, and an average hemoglobin level of 11.4 +/- 2.7 g/dL, whereas the controls had an average hemoglobin level of 13.1 +/- 2.5 g/dL. Twenty percent had hemoglobin levels below 9.5 g/dL. These children had more episodes of acute otitis media when compared with children with average levels. By increasing the hemoglobin level in these children, the frequency of the episodes of acute otitis media decreased significantly.

CONCLUSIONS

This study confirms that anemic children have higher prevalence of episodes of acute otitis media in comparison to healthy, nonanemic children, and shows that there is a direct relationship between the degree of the anemia and the number of the episodes.

The role of respiratory viruses in otitis media

Evidence derived from numerous studies ranging from animal experiments to extensive clinical trials supports a crucial role for respiratory viruses in acute otitis media. Viral infection of the upper respiratory tract initiates the whole cascade of events that ultimately leads to development of acute otitis media, and viruses contribute to the pathogenesis of this disease by several mechanisms. Recent data indicate that at least some types of viruses actively invade the middle ear and may also interfere with the outcome of otitis media. The availability of effective vaccines against the principal viruses predisposing to acute otitis media could be expected to result in a substantial reduction in the incidence of this disease.

Role of viruses in the pathogenesis of acute otitis media

To date there is ample evidence suggesting a crucial role for respiratory viruses in the pathogenesis of AOM. Respiratory viral infection appears to initiate the cascade of events that finally leads to development of AOM (Fig. 1). The pathogenesis of AOM is complicated, involving a network of factors, some probably not yet identified, which affect each other in a time-dependent manner. Increased knowledge of the detailed mechanisms of viral infection, the host inflammatory response during URI and the interaction between viruses and bacteria could lead to major advances in the prevention of AOM.

Increasing importance of viruses in acute otitis media

Acute otitis media is generally considered a simple bacterial infection that can be effectively treated with antibiotics. However, despite the extensive use of broad-spectrum antibiotics, poor clinical response to treatment of acute otitis media is common in children. Numerous studies ranging from animal experiments to extensive clinical studies have clearly demonstrated that respiratory viruses play a crucial role in the aetiology and pathogenesis of acute otitis media. Viral infection of the upper respiratory tract initiates the whole cascade of events that finally leads to the development of acute otitis media as a complication. Respiratory viruses induce a release of inflammatory mediators in the nasopharynx, increase bacterial colonization and adherence, and have a suppressive effect on the host's immune defense. Recent data indicate that at least some types of viruses actively invade the middle ear. Viruses also seem to enhance the inflammatory process in the middle ear and impair the outcome of the disease. Vaccines against the major viruses predisposing to acute otitis media hold a great promise for the prevention of this disease. Major advances in the management of acute otitis media will require further research into the mechanisms of viral infection, viral-bacterial interaction and the host inflammatory response during viral infection.

Occurrence of otitis media in an arctic region

The occurrence of otitis media (OM) was examined retrospectively in files at Longyearbyen Hospital, Svalbard, Norway during 1991-1994. Acute OM (AOM) with and without spontaneous drum perforation, secretory OM (SOM) and chronic OM (COM) with and without suppuration were registered, as were patient's sex, age, and climatic conditions. These findings were compared with weather observations obtained from the Norwegian Meteorological Institute, Tromsø in the same period. Sixty-four percent of the OM patients registered were classified as AOM, 17% having a spontaneous drum perforation. Thirty percent suffered from SOM, whereas 6% had COM. Forty percent of the patients were younger than 6 years. The distribution of OM cases during the year showed a peak during the spring, especially in May. Another minor peak was noted in September. Average daily temperature in the period was -5.6 degrees C, range -14 degrees C to +6 degrees C. Humidity and precipitation were fairly stable throughout the observation period 74% and 240 mm/year, respectively. OM is a common disease at Svalbard and is apparently related to seasonal shifts in temperature.

Antibodies to pneumococcal polysaccharides in human milk: lack of relationship to colonization and acute otitis media

BACKGROUND

This study analyzed antibodies to pneumococcal polysaccharides in human milk and their effect on nasopharyngeal colonization and acute otitis media in breast-fed infants.

METHODS

A total of 503 milk samples were collected from 310 mothers. Nasopharyngeal cultures were obtained from their children at 2, 6 and 10 months postpartum, and the capsular groups/types of the Streptococcus pneumoniae isolates were determined.

RESULTS

Types 6A, 6B, 19A, 19F and 23F accounted for 54% of the pneumococcal isolates, but type 3 isolates were uncommon. Milk samples were analyzed for antibody activity to the common capsular polysaccharide types 6A, 19F and 23F; to the type 3 polysaccharide; to C-polysaccharide; and to phosphorylcholine (PC), a major component of the pneumococcal cell wall polysaccharide (CWPS). Anti-capsular antibody activity was low or absent in > 90% of the milk samples. In contrast anti-PC antibody activity was detected in 88% and anti-CWPS in 84% of the samples. The frequency of acute otitis media did not vary with the milk anti-capsular, anti-PC or anti-CWPS antibody activity.

CONCLUSIONS

There was no reduction in nasopharyngeal carriage of S. pneumoniae among children fed milk with anti-capsular or anti-PC antibody activity, but carriage was increased in those children who received milk with anti-CWPS antibody activity. A protective role of antipolysaccharide or anti-CWPS antibodies in milk was not detected under the study conditions.

Healing of tympanic membrane after myringotomy during Streptococcus pneumoniae otitis media. An otomicroscopic and histologic study in the rat

The purpose of our study was to elucidate the course of healing of the tympanic membrane (TM) when myringotomy was performed during acute otitis media. The early and long-lasting structural changes of the TM were studied in an animal model. Rats were inoculated with Streptococcus pneumoniae (PnC) type 3 in the bulla. When the infection was manifest, myringotomy was performed. On days 4 and 12, and 3 and 6 months after myringotomy, the TM status was checked by otomicroscopy and TMs were prepared for light and electron microscopy. Comparison was made with PnC-infected TMs that were not perforated, as well as myringotomized noninfected TMs. The infection resolved more slowly in myringotomized ears compared to PnC-infected ears that were left untouched. After 6 months, the pars tensa of the myringotomized infected ears was thickened and showed a disorganized collagen structure, compared with myringotomized noninfected ears, in which TMs were normalized. The PnC-infected TMs without myringotomy were completely normalized after 2 months. We conclude that a combination of bacterial infection and myringotomy causes long-lasting changes in TM structure. This impaired structure of the connective tissue could be of importance in chronic middle ear disease as a presumptive site for retraction and perforation of the TM.

Interferon production by leukocytes in children with otitis media with effusion

We have previously shown that leukocyte cultures of children suffering from recurrent respiratory tract infections produce less interferon (IFN) than those of healthy children. In the present study this tentative marker of recurrent infections was used to study the pathogenetic background of otitis media with effusion (OME). Altogether 57 consecutive children, aged 2-11 years, who came for tympanostomy and/or adenoidectomy were divided into three subgroups: 25 of them had OME and a history of recurrent acute otitis media (rAOM/OME+), 20 had OME without an infectious background (inf-/OME+), and 12 had a history of recurrent upper respiratory infections (inf +/OME-) without OME. All the children were free of acute illness at the time of sampling. Differences between the groups were seen in IFN yields when leukocyte cultures were stimulated with adeno-, rhino-, corona-, respiratory syncytial or influenza A viruses. Leukocytes from inf-/OME+ children produced more IFN than those of the other two groups. Though no sex differences in the IFN responses were seen among rAOM/OME+ and inf +/OME- children, leukocytes from inf-/OME+ girls produced significantly higher amounts of IFN than those of inf-/OME+ boys, or rAOM/OME+ and inf +/OME- children. These differences between clinically different groups of children support the view that the etiology of OME can be heterogeneous.

Outcome-Oriented Managed Care Comparing Efficacies of Cefaclor and Amoxicillin in Acute and Recurrent Acute Otitis Media

A study utilizing outcome-oriented care is employed to show the effectiveness of a given medical treatment. A specific patient population is studied in order to determine the most effective treatment for a common clinical disorder. A total of 201 children were retrospectively studied to evaluate the efficacy and side effects of amoxicillin and cefaclor in the treatment of acute otitis media and recurrent acute otitis media. There were 456 episodes of acute otitis media; 245 episodes were treated with amoxicillin with an efficacy of 91%, while 211 episodes were treated with cefaclor with an efficacy of 97%. The dosage of 40mg/kg/day, divided in three equal doses, was employed for both antibiotics in the treatment of acute otitis media, while half of this amount was given once daily for the chemoprophylaxis of recurrent acute otitis media. In the 87 courses of chemoprophylaxis with cefaclor for recurrent otitis media, the efficacy was found to be 53%; while amoxicillin was found to be effective in 30% of the 33 patients studied. There were fewer side effects noted in the cefaclor group than in the amoxicillin group (4% vs. 12%). Both drugs caused diarrhea, while cefaclor also caused a mild maculopapular rash in two patients (1.67%).

While amoxicillin remains the drug of choice for acute otitis media (AOM), this study suggests that cefaclor may be a better selection in the chemoprophylaxis of recurrent acute otitis media.

Experimental recurrent otitis media induced by Haemophilus influenzae: protection and serum antibodies

PURPOSE

To study whether acute otitis media caused by encapsulated or nontypeable Haemophilus influenzae confers cross-reactive protective immunity in an animal model system and to explore the possible involvement of various humoral specific antibodies in protection.

MATERIALS AND METHODS

Rats were intrabullarly challenged with H influenzae type b and two different nontypeable H influenzae strains. One month after the initial infection, the animals were rechallenged ipsilaterally or contralaterally with either a homologous or heterologous strain, and the susceptibility to reinfection was investigated by otomicroscopy.

RESULTS

The animals challenged and rechallenged with the type b strain were well-protected ipsilaterally and contralaterally, while the protection after homologous rechallenge with a nontypeable strain was partial in the ipsilateral ear and very poor in the contralateral ear. Middle ears previously infected with a nontypeable strain remained fully susceptible to infections with heterologous strains, but there was an indication of cross-protection in the animal groups where the first episode of acute otitis media was caused by type b and the second by a nontypeable strain. Using the Western blot technique and an enzyme linked immunosorbant assay, the serological response to different outer membrane proteins, especially protein D, of H influenzae during and after middle ear infection were investigated. The serological response from the type b infected animals were generally more distinct, while the antibody levels against protein D were lower in these groups compared with the groups infected with nontypeable strains.

CONCLUSIONS

These data indicate that H influenzae type-b-induced experimental otitis media results in a better protection than a nontypeable-induced, and H influenzae b confers a cross protection.

Otitis media in a population of black American and white American infants, 0-2 years of age

To determine the incidence of otitis media (OM) and the bacteriology of acute otitis media (AOM) in a clinic population of young children in Pittsburgh, 138 black infants and 60 white infants were followed from birth to 2 years of age, examined at monthly intervals and whenever an upper respiratory tract infection (URI) or OM intervened. By 24 months of age the cumulative incidence of episodes of AOM was 43% and 42%, and of episodes of middle-ear effusion (MEE) was 86% and 85% in black and white infants, respectively. The average rate of episodes of AOM was 0.41 and 0.39 and of episodes of MEE was 1.68 and 1.70 in black and white infants, respectively. Tympanocentesis was performed for episodes of AOM and the following organisms were isolated from black and white infants, respectively: Streptococcus pneumoniae 43% and 43% of episodes; Moraxella catarrhalis 24% and 24%; non-typable Haemophilus influenzae 18% and 24%; and Haemophilus influenzae type b 5% and 0%. In both black and white infants first born children had less ear disease. We found no difference in the incidence of otitis media during the first 2 years of life between black and white infants.

Early structural changes in the rat tympanic membrane during pneumococcal otitis media

The early inflammatory reaction in the rat tympanic membrane was studied during the first 36h following inoculation of Streptococcus pneumoniae type 3 in the middle ear cavity. Otomicroscopic examination showed only minor signs of inflammation in the early stages although changes at the light microscopic level were pronounced. This reaction differed significantly between the pars flaccida and pars tensa of the tympanic membrane. Three hours after inoculation, edema and infiltration with polymorphonuclear leukocytes and macrophages were found in the pars flaccida whereas in the pars tensa no polymorphonuclear leukocytes were noted until after 12h. This reaction was most prominent after 36h. In the pars flaccida, mitoses occurred frequently among the cells of the simple squamous epithelium, which changed into a double-layered cuboidal epithelium. These findings demonstrate that an inflammatory reaction starts earlier in the pars flaccida than in the pars tensa of the tympanic membrane.

Language development in children with recurrent acute otitis media during the first three years of life. Follow-up study from birth to seven years of age

From a cohort of 113 children, followed prospectively from birth during the first three years of life regarding different aspects of acute otitis media (AOM), two study groups were selected for the present investigation: 13 children with recurrent AOM (rAOM, i.e. at least six episodes of AOM during a 12-month period), and 29 children without any AOM episode. The purpose of this study was to analyse the possible effects of early onset rAOM on language development as assessed at four and seven years of age at phoniatric and linguistic examinations performed blindly. There were no differences between the two groups on any of the linguistic analyses performed, although the rAOM group manifested a somewhat better performance on auditory discrimination tests at four years of age. The results of the present study show that rAOM during the first three years of life, in otherwise healthy children, does not cause a detectable delay of language development at four and seven years of age.

Enzyme immunoassay for detection of immunoglobulin G (IgG), IgM, and IgA antibodies against type 6B pneumococcal capsular polysaccharide and cell wall C polysaccharide in chinchilla serum

Conjugation of the capsular polysaccharides of Streptococcus pneumoniae to protein carriers has introduced a new generation of pneumococcal vaccines which may be efficacious in preventing pneumococcal otitis media during infancy. The chinchilla model has been used extensively for studying the pathogenesis of pneumococcal otitis media and for testing the efficacy of early pneumococcal capsular polysaccharide (PCP) vaccines, but immunologic studies in the chinchilla have been limited by the lack of antibodies against specific immunoglobulin isotypes. By using affinity-purified rabbit immunoglobulin G (IgG) anti-chinchilla IgG, IgM, and IgA, we developed a sensitive enzyme immunoassay that is highly specific for IgG, IgM, and IgA antibodies against type 6B PCP (anti-6B) and against C polysaccharide in chinchilla serum. Antibody titers increased in serum from five chinchillas immunized with a type 6B outer membrane protein complex vaccine. Increases of anti-6B IgG and IgM antibody titers were more striking than increases of anti-6B IgA or anti-C polysaccharide IgG, IgM, or IgA titers were.

Serum antibodies against respiratory tract viruses in episodes of acute otitis media

Although the findings of epidemiological studies have suggested viral respiratory tract infection (RTI) to be crucially involved in the development of acute otitis media (AOM), the relationship between AOM and viral RTI remains unclear. Serum samples, obtained in the acute and convalescent phases of 57 AOM episodes (in 35 children during the first three years of life) were analysed for IgG antibodies against influenza A viruses, influenza B viruses, parainfluenza virus type 1, respiratory syncytial virus and adenoviruses. One third of the AOM episodes (18/57) could be related to viral RTI, as evidenced by significant increases in viral serum antibody activity. Treatment failure occurred in four AOM episodes where increases in serum viral antibody activity were noted. In three of these failures, antibiotic treatment was unsuccessful despite the bacterial strains not being resistant to the drug used. This suggests that concomitant viral infection may be a determinant of treatment outcome in some AOM episodes.

The occurrence of acute otitis media in infants. A life-table analysis

A random sample of 2512 children were monitored to an average age of two years to determine the occurrence of acute otitis media (AOM). A life-table methodology was employed in the analysis. The cumulative incidence of the first episode of AOM up to 12 months of age was 42.4% (95% confidence interval 40.4-44.4) and the corresponding figure up to 24 months of age was 71.0% (68.9-73.1). The incidence rate for all acute otitis media episodes was 0.93 episodes per child per year (0.90-0.96) during the first 24 months of life increasing in the spring and autumn. The risk of experiencing an episode of acute otitis media increased at the age of 6-12 months and decreased slowly during the second year of life. The results confirm the frequent nature of acute otitis media and stress the necessity for clear, consistent definition of the criteria for acute otitis media in epidemiological research.

Double-blind comparison of cefixime and cefaclor in the treatment of acute otitis media in children

In a double-blind study cefixime, an oral cephalosporin of the third generation, was compared to cefaclor in the treatment of acute otitis media in 397 children aged 6 months to 12 years. Clinical evaluation was carried out at the beginning, at day 10-12 and day 28-35 after the start of the treatment. Specimens for bacterial culture and sensitivity testings were taken from the nasopharynx at the initial visit. Patients were randomized either to cefixime in a dose of 8 mg/kg/day or cefaclor in a dose 40 mg/kg/day in the proportion of 2 cefixime patients to 1 cefaclor patient. Two daily doses were administered for 7 days. At day 10-12, 93.5% in the cefixime group and 90.5% in the cefaclor group (p = 0.08) were clinically cured or improved. At day 28-35 the rate of cured or improved patients had decreased, mostly due to reinfections, to 90.1% in the cefixime group and to 86.6% in the cefaclor group (p = 0.12), respectively. 375 patients (69.9%) had positive bacterial culture in the nasopharynx of at least one strain of Haemophilus influenzae, Streptococcus pneumoniae, Branhamella (Moraxella) catarrhalis or combinations of these 3.73.6% of the B. catarrhalis strains were beta-lactamase producing and 11.4% of the H. influenzae strains, respectively. All isolated bacteria were sensitive to cefixime. Adverse events were reported in 17.9% in the cefixime and 10.6% in the cefaclor group. Most reactions were of moderate or mild nature and mostly affected skin or the gastrointestinal region. No serious adverse experiences occurred. In view of the good clinical results obtained cefixime seems to be at least as effective as cefaclor in the treatment of acute otitis media in children.

Recurrent acute otitis media. A prospective study of children during the first three years of life

To evaluate possible risk factors for developing recurrent acute otitis media (rAOM), 113 children were followed prospectively from birth to the age of 3 years. One of the aims was to determine whether such risk factors could be identified before the onset of the recurrences, so that optimal care and prophylactic measures could be made available at an early stage in such cases, on the basis of continuous follow-up by an ENT specialist. During the follow-up, 13 children developed rAOM, defined as six or more episodes of acute otitis media (AOM) during a 12-month period, 57 children had occasional episodes of AOM, and 43 children had no AOM at all. Of the children with onset of AOM before 6 months of age, 80% developed frequent episodes of AOM. The frequency of other respiratory tract infections and of family histories of otitis-proneness was higher among rAOM children than among the other children. The development of rAOM was unrelated to such factors as sex, familial history of allergy, duration of breast-feeding, or domestic environment. Nor could attendance at day-care centres be concluded as constituting a risk factor for the development of rAOM. An onset of AOM before 6 months of age was highly predictive of subsequent recurrent bouts of AOM, which emphasizes the importance of correct diagnosis in infants.

The Bayesian approach to the evaluation of risk factors in acute and recurrent acute otitis media

A multivariant modelling method was used to analyse the risk, associated with 22 different factors, of contracting acute otitis media (AOM) in a prospective cohort of 1294 urban children followed up to the age of 17-32 (mean 25) months. By far the most important risk factor was the caring of the child at a day-care centre. The importance of this factor further increased with increasing recurrence of the attacks. Next in order came the existence of sibling(s) with AOM attacks during the follow-up. Prolongation of breastfeeding increased the protection against AOM during the first year of life. The frequency of AOM attacks was lowest around midsummer and highest in early winter.

Incidence of acute otitis media up to the age of 1 1/2 years in urban infants

The object of this prospective cohort investigation of 1,642 infants was to study the incidence of acute otitis media (AOM) in urban children during the first 18 months of life. The monthly incidence of AOM was greatest at the age of 10 months, and the largest proportion of children with AOM was also found in this 10-month age group. Before the age of 18 months, 56.7% of the infants had had at least one episode of AOM, while 26.9% had had one or two episodes and 29.8% three or more. The corresponding figures before the age of 12 months were: 45.3%; 26.8%; 18.5%, and before the age of 9 months: 30.5%; 22.1%; 8.4%. The AOM incidence, particularly as regards recurrent AOM, was rather higher in boys than in girls.

Risk factors affecting the occurrence of acute otitis media among 2-3-year-old urban children

The factors affecting the occurrence and recurrence of acute otitis media (AOM) were studied among 471 2-3-year-old children in two cities in Finland. Of these children, 188 had experienced greater than or equal to 3 attacks of AOM, 76 had had 1-2 attacks and 207 no otitis attacks (= control group). The study showed that the risk of recurrent AOM was increased among those children attending day-care nurseries as well as among those who had several siblings. Proneness to rhinorrhea and exposure to passive smoking at home was associated with an increased risk of AOM, while prolonged breast-feeding (greater than 6 months) seemed to reduce it. No correlation was found between the risk of recurrent AOM and the place of residence or type of housing, the parental otitis history, or atopic diathesis of a child. Thus the study suggested that to protect a young child from AOM we should promote breast-feeding and home-care for babies as well as avoid smoking in the home.

Prevention of otitis media in children by pneumococcal vaccination

A total of 3,340 infants, 95 per cent of them 7 to 9 months old, were randomly vaccinated in a double-blind fashion with either the 14-valent pneumococcal (Pn) polysaccharide vaccine or a saline placebo in three urban areas in Finland. The second dose of the vaccine was given 5 months later. Age and sex distribution, recruitment of infants, and their otitis-related treatment and follow-up were similar in the study areas. Side effects after vaccination were mild and fewer than among older children. Antibody responses to vaccine polysaccharides varied from type to type, but were generally poor, especially to types most prevalent in otitis media. After the first dose of vaccine, the occurrence of otitis visits among the Pn-vaccinated, as compared with controls, showed inter-area differences, but ranged from not more than a 30 per cent reduction at its best to an increase in some areas and in some clinical categories. The respective figures for children with acute otitis media were similar between the vaccination groups and the study areas. The effect of the vaccine on acute otitis media caused by specific Pn types/groups represented in the vaccine was variable but generally poor. Group 6 attacks especially seemed to behave problematically. The second dose of the vaccine did not give additional benefit serologically or clinically. The efficacy of currently available pneumococcal vaccine against otitis media seemed poor in infants.

Acute otitis media. An animal experimental study

This paper describes an investigation performed to study the middle ear events ensuing from Staphylococcus aureus induced infection in the middle ear cavity of the rat. To obtain an evaluation at both the cell and the tissue level, scanning electron microscopy, transmission electron microscopy and histology were used. Staphylococcus aureus infection appears to be characterized by five major events: (i) cellular response, (ii) humoral response, (iii) mucociliary response, (iv) fibroblastic response, (v) bony response. Since these occurrences correspond to the events witnessed in the human middle ear affected by acute otitis media, S. aureus achieved infection might prove a useful tool for the further study of this disease, by means of animal experiments.