Otitis media: back to basics

Relationship between sleep position and otitis media in infants: The Japan environment and children's study

OBJECTIVE

Otitis media is a disease that commonly occurs in infants. Various risk factors have been reported. Sleep position has been reported to be associated with various diseases. There is no report on the relationship between otitis media and sleep position. We examined the incidence of otitis media and sleep position in infants.

METHODS

We used data from the Japan Environment Children's Study. We used multivariate logistic analysis to examine the relationship between sleep position and the incidence of otitis media in infants aged up to 6 months. In addition, we conducted a stratified analysis based on whether the child was able to turn over in bed at 6 months of age.

RESULTS

The study population comprised 85,731 participants. The incidence of otitis media by sleep position was significantly higher when the infant was in the prone position compared to any other position (adjusted odds ratio, 1.206; 95 %CI, 1.038-1.401). Stratified analysis of turning showed that otitis media was more common in the prone position in all groups.

CONCLUSION

In the current study, infants aged 6 months or younger who slept in the prone position were more likely to have otitis media. Sleep position interview and guidance on changing sleep position may be useful for the prevention of otitis media.

The characterization of Moraxella catarrhalis carried in the general population

Moraxella catarrhalis is a common cause of respiratory tract infection, particularly otitis media in children, whilst it is also associated with the onset of exacerbation in chronic obstructive pulmonary disease in adults. Despite the need for an efficacious vaccine against M. catarrhalis, no candidates have progressed to clinical trial. This study, therefore, aimed to characterize the diversity of M. catarrhalis isolated from the upper respiratory tract of healthy children and adults, to gain a better understanding of the epidemiology of M. catarrhalis and the distribution of genes associated with virulence factors, to aid vaccine efforts. Isolates were sequenced and the presence of target genes reported. Contrary to prevailing data, this study found that lipooligosaccharide (LOS) B serotypes are not exclusively associated with 16S type 1. In addition, a particularly low prevalence of LOS B and high prevalence of LOS C serotypes was observed. M. catarrhalis isolates showed low prevalence of antimicrobial resistance and a high gene prevalence for a number of the target genes investigated: ompB2 (also known as copB), ompCD, ompE, ompG1a, ompG1b, mid (also known as hag), mcaP, m35, tbpA, lbpA, tbpB, lbpB, msp22, msp75 and msp78, afeA, pilA, pilQ, pilT, mod, oppA, sbp2, mcmA and mclS.

Features predicting treatment failure in pediatric acute otitis media

OBJECTIVES

To facilitate better antibiotic stewardship, we conducted this clinical trial to identify the prognostic features of treatment failure in pediatric acute otitis media (AOM).

STUDY

Design: This is a randomized, parallel-group, open-label, comparative clinical trial.

SUBJECTS AND METHODS

Children with AOM and aged between 1 month and 5 years were enrolled. Patients were randomly assigned to receive either amoxicillin alone (70 mg/kg) for five days, or the same with additional clarithromycin (15 mg/kg) for the initial three days. The clinical course of AOM was evaluated based on tympanic membrane scores. Failure of treatment for AOM was confirmed on day 14. Nasal conditions were also assessed by a clinical scoring system for acute rhinosinusitis.

RESULTS

Treatment failures occurred in 25 out of 129 (19.4%) children. The ratio of treatment failures by age was significantly higher in children younger than 2 years than in children older than 2 years. The tympanic membrane scores on day 3 (P = 0.0334) and day 5 (P < 0.0001) and acute rhinosinusitis scores on day 5 (P = 0.0004) were higher in failure cases than in cured cases. Multivariate logistic regression analysis indicated significant associations between the treatment failure with tympanic membrane scores and acute rhinosinusitis scores on day 5, and the antimicrobial treatment regimen.

CONCLUSIONS

Improvement of acute rhinosinusitis and tympanic membrane scores on day five were important predictive features in failure of treatment for pediatric AOM. These results will be useful when discussing the treatment decisions with the patient's parents.

Clinical practice guidelines for the diagnosis and management of acute otitis media in children-2018 update

OBJECTIVE

"Clinical Practice Guidelines for the Diagnosis and Management of Acute Otitis Media in Children-2018 update (2018 Guidelines)" aim to provide appropriate recommendations about the diagnosis and management of children with acute otitis media (AOM), including recurrent acute otitis media (recurrent AOM), in children under 15 years of age. These evidence-based recommendations were created with the consensus of the subcommittee members, taking into consideration unique characteristics of bacteriology and antimicrobial susceptibilities of AOM pathogens in Japan, as well as global advances in vaccines.

METHODS

The subcommittee re-evaluated key clinical issues based on SCOPE (a master plan of the guidelines) and created clinical questions (CQ) about the diagnosis and management of AOM patients. A literature search of the publications from 2013 to 2016 were added to the Guidelines 2013, not only to assess the evidence on the effectiveness of vaccines, but also to provide up to date information of the bacteriology and antimicrobial susceptibilities of AOM causative pathogens in Japan.

RESULTS

We have proposed guidelines for disease severity-based management of AOM patients, after classifying AOM severity into mild, moderate, and severe, based on age, clinical manifestations, and otoscopic findings.

CONCLUSIONS

Precise otoscopic findings are essential for judging AOM severity, which can lead to appropriate management of AOM patients.

Increased Virulence of an Encapsulated Streptococcus pneumoniae Upon Expression of Pneumococcal Surface Protein K

Background

Current Streptococcus pneumoniae vaccines selectively target capsular polysaccharide of specific serotypes, leading to an increase in nonencapsulated S. pneumoniae (NESp). Cocolonization by encapsulated pneumococci and NESp increases the opportunity for intraspecies genetic exchange. Acquisition of NESp genes by encapsulated pneumococci could alter virulence and help vaccine-targeted serotypes persist in the host.

Methods

Adhesion and invasion assays were performed using immortalized human pharyngeal or lung epithelial cells. In vivo models assessing murine nasopharyngeal colonization and pneumonia, as well as chinchilla otitis media (OM), were also used.

Results

Pneumococcal surface protein K (PspK) expression increased encapsulated pneumococcal adhesion and invasion of lung cells and enhanced virulence during pneumonia and OM. Additionally, PspK increased nasopharyngeal colonization, persistence in the lungs, and persistence in the middle ear when expressed in a capsule deletion mutant. Competition experiments demonstrated encapsulated pneumococci expressing PspK also had a selective advantage in both the lungs and nasopharynx.

Conclusions

PspK increases pneumococcal virulence during pneumonia and OM. PspK also partially compensates for loss of virulence in the absence of capsule. Additionally, PspK provides a selective advantage in a competitive environment. Therefore, acquisition of PspK increases encapsulated virulence in a condition-dependent manner. Together, these studies demonstrate risks associated with pneumococcal intraspecies genetic exchange.

The association between gestational age and otitis media during childhood: a population-based cohort analysis

Otitis media (OM) carries a tremendous global health burden and potentially severe long-term consequences. The objective of this study was to determine the impact of birth at different gestational ages on the incidence of childhood OM.A population-based cohort analysis was conducted. All singleton deliveries occurring between 1991 and 2014 at a regional tertiary medical center were included. Gestational age on delivery was divided into six subgroups: early (&lt;34 weeks gestation; 0 out of 7) and late (34 weeks gestation; 0 out of 7 to 36 weeks gestation; 6 out of 7) preterm, and early (37 weeks gestation; 0 out of 7 to 38 weeks gestation; 6 out of 7), full (39 weeks gestation; 0 out of 7 to 40 weeks gestation; 6 out of 7), late (41 weeks gestation; 0 out of 7 to 41 weeks gestation; 6 out of 7) and post (⩾42 weeks 0 out of 7) term deliveries. Rates of OM-related hospitalizations up to 18 years of age were assessed. Weibull parametric hazards model was used to study the association between gestational age at birth and the risk for OM-related hospitalizations while controlling for potential confounders.During the study period, 238,622 deliveries met the inclusion criteria. OM-related hospitalizations of the offspring (n=4724) were significantly more common in the preterm (early 3.6%, late 2.4%) and early-term born children (2.2%) and decreased gradually across the full (1.9%), late (1.7%) and post (1.6%) term groups (χ2-test for trends P&lt;0.001). In the Weibull regression model, early preterm, as well as early-term deliveries exhibited an independent association with pediatric OM (adjusted hazard ratios: 1.67 and 1.09, respectively, P&lt;0.02).Deliveries occurring at preterm and early term are associated with higher rates of pediatric OM-related hospitalizations, which decrease gradually as gestational age advances.

Polyamine transporter potABCD is required for virulence of encapsulated but not nonencapsulated Streptococcus pneumoniae

Streptococcus pneumoniae is commonly found in the human nasopharynx and is the causative agent of multiple diseases. Since invasive pneumococcal infections are associated with encapsulated pneumococci, the capsular polysaccharide is the target of licensed pneumococcal vaccines. However, there is an increasing distribution of non-vaccine serotypes, as well as nonencapsulated S. pneumoniae (NESp). Both encapsulated and nonencapsulated pneumococci possess the polyamine oligo-transport operon (potABCD). Previous research has shown inactivation of the pot operon in encapsulated pneumococci alters protein expression and leads to a significant reduction in pneumococcal murine colonization, but the role of the pot operon in NESp is unknown. Here, we demonstrate deletion of potD from the NESp NCC1 strain MNZ67 does impact expression of the key proteins pneumolysin and PspK, but it does not inhibit murine colonization. Additionally, we show the absence of potD significantly increases biofilm production, both in vitro and in vivo. In a chinchilla model of otitis media (OM), the absence of potD does not significantly affect MNZ67 virulence, but it does significantly reduce the pathogenesis of the virulent encapsulated strain TIGR4 (serotype 4). Deletion of potD also significantly reduced persistence of TIGR4 in the lungs but increased persistence of PIP01 in the lungs. We conclude the pot operon is important for the regulation of protein expression and biofilm formation in both encapsulated and NCC1 nonencapsulated Streptococcus pneumoniae. However, in contrast to encapsulated pneumococcal strains, polyamine acquisition via the pot operon is not required for MNZ67 murine colonization, persistence in the lungs, or full virulence in a model of OM. Therefore, NESp virulence regulation needs to be further established to identify potential NESp therapeutic targets.

Immunogenicity and protective immunity against otitis media caused by pneumococcus in mice of Hib conjugate vaccine with PsaA protein carrier

This study evaluated the immunogenicity and protective immunity of a Hemophilus influenzae b (Hib) polysaccharide conjugate vaccine with the pneumococcal surface adhesin A (PsaA) protein carrier in young mice. The Hib polysaccharide was conjugated with the rPsaA protein carrier, which was produced using recombinant DNA technology. A total of 15 young mice aged 3 weeks to 5 weeks were immunized with the conjugate vaccine, and another 15 young mice of the same age were immunized with the licensed Hib-tetanus toxoid (TT) vaccine. Furthermore, the third group of 15 young mice was inoculated with phosphate buffer saline as control. The immunized mice were inoculated with pneumococcus in the middle ear. Results showed that IgG antibody responses against both the PsaA protein and Hib polysaccharide were observed in the Hib-PsaA group. However, no statistical difference was observed in the titer of IgG against the Hib polysaccharide between Hib-PsaA and Hib-TT groups. The elimination rate of pneumococcus and the inflammation of the middle ear showed the effectiveness of protective immunity against otitis media caused by pneumococcus. Our results suggest that the Hib polysaccharide can be successfully conjugated with rPsaA via amide condensation. This new Hib-PsaA conjugate vaccine can induce both anti-PsaA and anti-Hib immune responses in young mice and elicit effective protection against acute otitis media caused by pneumococcus.

Randomized controlled trial of juzen-taiho-to in children with recurrent acute otitis media

OBJECTIVE

Recurrent acute otitis media (AOM) in young children is rapidly increasing worldwide. Repeated antibiotic use leads to antibiotic-resistant pathogen development. Complementary and alternative medicine approaches have been suggested as a supplemental treatment option to conventional antimicrobial medicine. This randomized, parallel-group, open-label, non-herbal medicine controlled trial assessed the efficacy of a traditional Japanese herbal medicine, juzen-taiho-to (JTT) for AOM prevention in otitis-prone children.

METHODS

Children prone to recurrent AOM aged 6-48 months were recruited from 26 otolaryngology clinics in Japan and received conventional AOM treatment based on Japanese guidelines with or without 2 daily oral doses of JTT (0.10-0.25g/kg/day). The mean number of AOM episodes, coryza episodes, and duration of total antibiotic administration per month were compared during 3-month intervention.

RESULTS

At least one episode of AOM was diagnosed in 71% of JTT-group and 92% of control participants during follow-up. JTT administration reduced the frequency of AOM episodes by 57% compared with children who received conventional treatment alone (0.61±0.54 vs. 1.07±0.72 AOM instances/month; P=0.005) and also significantly decreased number of coryza episodes (P=0.015) and total antibiotic administration (P=0.024).

CONCLUSIONS

This is the first report of recurrent AOM prevention by herbal medication. JTT appears to effectively prevent recurrent AOM in children. Subsequent double-blind studies are needed to confirm the beneficial effects of JTT on recurrent AOM and upper respiratory tract infections.

Factors Associated with Clinical Outcomes in Acute Otitis Media

Acute otitis media (AOM) is a common disease in childhood. If predictors of outcome in AOM were known, it would be possible to individualize therapy. Our aim was to identify factors that predict the outcome in AOM. We enrolled 368 children with AOM (ages, 10 to 86 months). The severity of symptoms and the severity of tympanic membrane changes were graded with a scoring system. Nasopharyngeal colonization with middle ear pathogens was determined on day 1. Three outcomes were assessed: persistence of symptoms at day 5, persistence of tympanic membrane changes at day 28, and recurrence of acute symptoms prior to day 28. Persistence of symptoms at day 5 was associated with younger age (35 versus 44 months; p < .001), higher symptom score on day 1 (3.5 versus 2.9; p < .05), and colonization with Streptococcus pneumoniae (61% versus 41%; p < .05). Persistence of tympanic membrane changes at day 28 was associated with younger age (39 versus 45 months; p < .01), higher tympanic membrane score on day 1 (4.1 versus 3.6; p < .01), and nasopharyngeal colonization with S pneumoniae, especially drug-resistant S pneumoniae (33% versus 13%; p < .05). Recurrence of acute symptoms prior to day 28 occurred in 14% of the children. Streptococcus pneumoniae was the only pathogen associated with an increased recurrence rate (23%) as compared to the group without pathogens (7%; p < .05). Age, severity of disease at presentation, and nasopharyngeal colonization patterns were proven to be important determinants of outcome in AOM.

Nano-transfersomal ciprofloxacin loaded vesicles for non-invasive trans-tympanic ototopical delivery: in-vitro optimization, ex-vivo permeation studies, and in-vivo assessment

Ciprofloxacin is a synthetic fluoroquinolone antibiotic that has been used for systemic treatment of otitis media in adults. It was approved for topical treatment of otorrhea in children with tympanostomy tubes. The aim of this work was to enhance the local non-invasive delivery of ciprofloxacin to the middle ear across an intact tympanic membrane (TM) in an attempt to treat acute otitis media (AOM) ototopically. In order to achieve this goal, ciprofloxacin nano-transfersomal vesicles were prepared by thin film hydration (TFH) technique, using several edge activators (EAs) of varying hydrophilic-lipophilic balance (HLB) values. A full factorial design was employed for the optimization of formulation variables using Design-Expert(®) software. The optimal formulation was subjected to stability testing, ex-vivo permeation studies (through ear skin and TM of rabbits), and in-vivo evaluation. Results revealed that the optimal formulation (composed of phospholipid and sodium cholate as an EA at a molar ratio of 5:1) exhibited enhanced ex-vivo drug flux through ear skin and TM when compared with the commercial product (Ciprocin(®) drops). It demonstrated a greater extent of in-vivo drug deposition in the TM of albino rabbits relative to Ciprocin(®). Consequently, transfersomes could be promising for the non-invasive trans-tympanic delivery of ciprofloxacin.

Microbial profiling does not differentiate between childhood recurrent acute otitis media and chronic otitis media with effusion

OBJECTIVES

Otitis media (OM) is one of the most frequent diseases of childhood, with a minority of children suffering from recurrent acute otitis media (rAOM) or chronic otitis media with effusion (COME), both of which are associated with significant morbidity. We investigated whether the microbiological profiling could be used to differentiate between these two conditions.

METHODS

Children up to five years of age, with rAOM (n = 45) or COME (n = 129) and scheduled for tympanostomy tube insertion were enrolled in a prospective study between 2008 and 2009. Middle ear fluids (n = 119) and nasopharyngeal samples (n = 173) were collected during surgery for bacterial culture and PCR analysis to identify Streptococcus pneumoniae, Haemophilus influenzae and Moraxella catarrhalis, and to detect 15 distinct respiratory viruses.

RESULTS

The occurrence of bacterial and viral pathogens in middle ear fluids did not significantly differ between patients suffering from rAOM and COME. In both patient cohorts, H. influenzae and rhinovirus were the predominant pathogens in the middle ear and nasopharynx. Nasopharyngeal carriage with two or three bacterial pathogens was associated with the presence of bacteria in middle ear fluid (P = 0.04). The great majority of the bacteria isolated from middle ear fluid were genetically identical to nasopharyngeal isolates from the same patient.

CONCLUSIONS

Based on these results, we propose that the common perception that rAOM is associated with recurrent episodes of microbiologically mediated AOM, whereas COME is generally a sterile inflammation, should be reconsidered.

Otitis media

Acute otitis media (AOM) is diagnosed based on visualization of a full or bulging tympanic membrane with middle ear effusion. The distribution of bacteria causing AOM in North America under the influence of pneumococcal conjugate vaccination and antibiotic selection pressure has resulted in a predominance of β-lactamase-producing Haemophilus influenzae followed by penicillin-resistant Streptococcus pneumoniae. Although guidelines continue to endorse amoxicillin as the preferred treatment, amoxicillin/clavulanate in high dosage would be the preferred treatment based on the otopathogen mix currently. Antibiotic prophylaxis has fallen into disfavor as a preventative strategy for AOM recurrences.

Formulations for trans-tympanic antibiotic delivery

We have developed a drug delivery system for prolonged trans-tympanic antibiotic delivery from a single dose administration. Increased permeability to ciprofloxacin of the intact tympanic membrane (TM) was achieved by chemical permeation enhancers (CPEs--bupivacaine, limonene, sodium dodecyl sulfate); this was also seen by CPEs contained within a hydrogel (poloxamer 407) to maintain the formulation at the TM. The CPE-hydrogel formulation had minimal effects on auditory thresholds and tissue response in vivo. CPE-hydrogel formulations have potential for ototopical delivery of ciprofloxacin for the treatment of acute otitis media (AOM) and other middle ear diseases.

The fundamental link between pneumococcal carriage and disease

Streptococcus pneumoniae (pneumococcus) is a major cause of worldwide mortality and morbidity, and to a large extent is vaccine-preventable. Nasopharyngeal carriage of pneumococcus precedes disease and is the source of pneumococcal spread between people. The use of vaccine effect on carriage as part of the vaccine licensure and post-vaccine introduction evaluation could facilitate and expand the licensure of new, life-saving pneumococcal vaccines and enable a comprehensive estimate of population effects after vaccine introduction. The authors provide a review of the evidence supporting pneumococcal carriage at the individual level as an immediate and necessary precursor to pneumococcal disease. Based on such a causal link between carriage and disease, the authors emphasize the role of information on pneumococcal carriage in vaccine trials and in public health decision-making.

Evaluation of a rapid immunochromatographic ODK-0901 test for detection of pneumococcal antigen in middle ear fluids and nasopharyngeal secretions

Since the incidence of penicillin-resistant Streptococcus pneumoniae has been increasing at an astonishing rate throughout the world, the need for accurate and rapid identification of pneumococci has become increasingly important to determine the appropriate antimicrobial treatment. We have evaluated an immunochromatographic test (ODK-0901) that detects pneumococcal antigens using 264 middle ear fluids (MEFs) and 268 nasopharyngeal secretions (NPSs). A sample was defined to contain S. pneumoniae when optochin and bile sensitive alpha hemolytic streptococcal colonies were isolated by culture. The sensitivity and specificity of the ODK-0901 test were 81.4% and 80.5%, respectively, for MEFs from patients with acute otitis media (AOM). In addition, the sensitivity and specificity were 75.2% and 88.8%, respectively, for NPSs from patients with acute rhinosinusitis. The ODK-0901 test may provide a rapid and highly sensitive evaluation of the presence of S. pneumoniae and thus may be a promising method of identifying pneumococci in MEFs and NPSs.

Epidemiological and microbiological characteristics of culture-proven acute otitis media in Taiwanese children

BACKGROUND/PURPOSE

Acute otitis media (AOM) is one of the most common diseases in children. Here, we describe the epidemiological and microbiological characteristics of AOM in Taiwanese children over a 10-year period.

METHODS

We retrospectively enrolled pediatric patients with culture-proven AOM who were treated at Mackay Memorial Hospital, Taipei between 1999-2008. The data include demographic characteristics, clinical history, and microbiological characteristics.

RESULTS

Six hundred and fourteen patients were included. The male:female ratio was 1.4 (p<0.001). Greater than three-fourths of the patients (476 [77.5%]) were < 5 years of age, and most patients were 1-2 years of age. The most common isolated pathogen was Streptococcus pneumoniae (419 patients [68.2%]), followed by nontypeable Haemophilus influenzae (NTHi; 118 patients [19.2%]). The distributions of age, gender, use of tympanocentesis, history of previous AOM, and use of antibiotic between patients infected with the two pathogens were not significantly different. However, the number of patients with AOM caused by S. pneumoniae, but not NTHi, decreased during the study period (p=0.004). Three hundred and eighty-seven children (63.0%) with AOM developed spontaneous otorrhea. Compared with patients who underwent tympanocentesis, those with spontaneous otorrhea were younger (27.0±16.4 vs. 31.1±15.2 months of age, p=0.004), more likely to have a previous history of AOM (p=0.019), and more likely to receive more antibiotics (p=0.012). The third most common pathogen was S. pyogenes (25 patients [4.1%]). S. pyogenes occurred more often in children > 5 years of age and was associated with spontaneous otorrhea (p<0.001).

CONCLUSION

S. pneumoniae and NTHi are common causes of culture-confirmed AOM in Taiwanese children. Although S. pyogenes is not as common, it usually causes AOM in children > 5 years of age and is associated with spontaneous otorrhea.

Infecções de repetição: o que é importante para o pediatra

OBJETIVO: Apresentar uma revisão atualizada sobre infecções de repetição em crianças, abordando importantes aspectos para o pediatra relacionados a infecções em crianças saudáveis e em crianças com imunodeficiências primárias. FONTES DE DADOS: Artigos relacionados ao tema foram coletados dos bancos de dados Medline e Lilacs no período entre 1980 e 2008, tendo sido selecionados artigos de meta-análise, revisão e estudos clínicos realizados em seres humanos, cuja metodologia e discussão estavam bem estruturadas. Também foram incluídos livros-texto nacionais e internacionais pertinentes ao tema. SÍNTESE DOS DADOS: Infecções de repetição são frequentes na clínica pediátrica. Aproximadamente 50% dessas crianças são saudáveis e 10% podem ser imunodeficientes. A criança saudável apresenta crescimento e desenvolvimento normais e se encontra bem entre os episódios infecciosos. As infecções, na maioria das vezes, não têm curso prolongado ou complicado e ocorrem devido ao aumento da exposição a agentes infecciosos do meio ambiente nos primeiros anos de vida. As imunodeficiências primárias geralmente se manifestam como infecções de repetição por microorganismos específicos ou por germes de baixa virulência. Na maioria das vezes, os quadros infecciosos apresentam evolução prolongada, resposta inadequada à antibioticoterapia e elevados riscos de complicações. CONCLUSÕES: O diagnóstico precoce das imunodeficiências primárias é essencial para que medidas terapêuticas sejam rapidamente instituídas, reduzindo os riscos de ocorrência de óbito e complicações.

Formation of Streptococcus pneumoniae non-phase-variable colony variants is due to increased mutation frequency present under biofilm growth conditions

In this report, we show that biofilm formation by Streptococcus pneumoniae serotype 19 gives rise to variants (the small mucoid variant [SMV] and the acapsular small-colony variant [SCV]) differing in capsule production, attachment, and biofilm formation compared to wild-type strains. All biofilm-derived variants harbored SNPs in cps19F. SCVs reverted to SMV, but no reversion to the wild-type phenotype was noted, indicating that these variants were distinct from opaque- and transparent-phase variants. The SCV-SMV reversion frequency was dependent on growth conditions and treatment with tetracycline. Increased reversion rates were coincident with antibiotic treatment, implicating oxidative stress as a trigger for the SCV-SMV switch. We, therefore, evaluated the role played by hydrogen peroxide, the oxidizing chemical, in the reversion and emergence of variants. Biofilms of S. pneumoniae TIGR4-DeltaspxB, defective in hydrogen peroxide production, showed a significant reduction in variant formation. Similarly, supplementing the medium with catalase or sodium thiosulfate yielded a significant reduction in variants formed by wild-type biofilms. Resistance to rifampin, an indicator for mutation frequency, was found to increase approximately 55-fold in biofilms compared to planktonic cells for each of the three wild-type strains examined. In contrast, TIGR4-DeltaspxB grown as a biofilm showed no increase in rifampin resistance compared to the same cells grown planktonically. Furthermore, addition of 2.5 and 10 mM hydrogen peroxide to planktonic cells resulted in a 12- and 160-fold increase in mutation frequency, respectively, and gave rise to variants similar in appearance, biofilm-related phenotypes, and distribution of biofilm-derived variants. The results suggest that hydrogen peroxide and environmental conditions specific to biofilms are responsible for the development of non-phase-variable colony variants.

Genetic polymorphisms in immunoresponse genes TNFA, IL6, IL10, and TLR4 are associated with recurrent acute otitis media

OBJECTIVE

Cytokines and other inflammatory mediators are involved in the pathogenesis of otitis media. We hypothesized that polymorphisms in inflammatory response genes contribute to the increased susceptibility to acute otitis media in otitis-prone children.

PATIENTS AND METHODS

DNA samples from 348 children with > or = 2 acute otitis media episodes, who were participating in a randomized, controlled vaccination trial, and 463 healthy adult controls were included. Polymorphisms in TNFA, IL1B, IL4, IL6, IL10, IL8, NOS2A, C1INH, PARP, TLR2, and TLR4 were genotyped. Genotype distributions in children with recurrent acute otitis media were compared with those in controls. Within the patient group, the number of acute otitis media episodes before vaccination and the clinical and immunologic response to pneumococcal conjugate vaccinations were analyzed.

RESULTS

The IL6-174 G/G genotype was overrepresented in children with acute otitis media when compared with controls. In the patient group, TNFA promoter genotypes -238 G/G and -376 G/G and the TLR4 299 A/A genotype were associated with an otitis-prone condition. Furthermore, lower specific anticapsular antibody production after complete vaccination was observed in patients with the TNFA-238 G/G genotype or TNFA-863 A allele carriage. Finally, the IL10-1082 A/A genotype contributed to protection from the recurrence of acute otitis media after pneumococcal vaccination.

CONCLUSIONS

Variation in innate immunoresponse genes such as TNFA-863A, TNFA-376G, TNFA-238G, IL10-1082 A, and IL6-174G alleles in the promoter sequences may result in altered cytokine production that leads to altered inflammatory responses and, hence, contributes to an otitis-prone condition.

Role of extra-esophageal reflux in chronic otitis media with effusion

OBJECTIVES/HYPOTHESIS

Otitis media with effusion (OME) is the most common cause of childhood hearing loss. Despite its prevalence, the enormous health care expenditures resulting from its treatment, and the increasing therapeutic challenges imposed by antimicrobial resistance, very little is known regarding the cellular and molecular immunologic and inflammatory events in this disease process. Extra-esophageal reflux (EER) has been implicated in the pathogenesis of chronic OME. The objective of this study was to confirm that children with OME have EER into the middle ear as measured by the presence of pepsin in middle ear effusions (MEE) removed during tympanostomy tube (TT) placement.

STUDY DESIGN

Prospective, translational, cell biological research study.

METHODS

MEE were obtained from children undergoing TT placement for OME. The fluid was lysed in a urea buffer and the presence of pepsin quantitatively determined by Western blot analysis using a specific antipepsin antibody. The pH of the samples was recorded before lysis.

RESULTS

Pepsin protein was detected in 18 of 32 (56%) samples analyzed, with 12 of 20 (60%) patients having at least one positive sample for pepsin. Pepsin levels ranged from 80 to 1,000 ng/mL. The pH of the samples ranged from 6.0 to 7.6, with a mean pH of 6.8.

CONCLUSIONS

Pepsin was detected in 60% of patients with OME, confirming that EER into the middle ear occurs in these children. The pepsin present would have little or no activity at pH 6.0 to 7.6; however, pepsin is stable below pH 8.0 and thus could be reactivated after a decrease in pH.

The 4G/4G plasminogen activator inhibitor-1 genotype is associated with frequent recurrence of acute otitis media

OBJECTIVES

Plasminogen activator inhibitor-1 counterregulates cell migration, adhesion, and tissue repair. The PAI1 4G/5G promoter polymorphism has an effect on expression levels of PAI1. After a first acute otitis media episode, children are at increased risk for a next episode. Because the PAI1 4G allele is associated with higher plasminogen activator inhibitor-1 production and, hence, decreased tissue repair, we hypothesize that this allele may contribute to increased recurrence of acute otitis media.

PATIENTS AND METHODS

The PAI1 4G/5G polymorphism was genotyped in 348 Dutch children aged 1 to 7 years who were suffering from recurrent acute otitis media and participating in a randomized, controlled trial and 463 healthy control subjects, representative of the general population.

RESULTS

No significant difference in PAI1 genotype distribution between the whole acute otitis media group and control subjects was observed. However, children with the PAI1 4G/4G genotype had an increased risk of more frequent acute otitis media episodes compared with those who were homozygous for the 5G variant, also after correction for cofactors. This finding was attributable to children <4 years of age.

CONCLUSIONS

Our findings suggest that the PAI1 4G/4G genotype is associated with an increased risk for the otitis-prone condition, potentially because of impaired healing after a previous otitis media episode.

Acute otitis media in children aged less than 2 years: drug treatment issues

The management of acute otitis media (AOM) in childhood has evolved considerably during recent years as a result of the new insights provided by publication (in 2004) of the American Academy of Pediatrics and the American Academy of Family Physicians guidelines for the treatment of AOM. The new treatment guidelines establish a clear hierarchy among the various antibacterials used in the treatment of this disease and also the use of an age-stratified approach to AOM by recommending an observation strategy ('watchful waiting') without the use of antibacterials for some groups of patients with AOM. Infants and young children aged <2 years represent a target population characterized by a high incidence of AOM (and in particular of recurrent disease), lack of anatomic and physiologic maturity of airways, age-related immune humoral and cellular deficiencies, the presence of antibacterial-resistant pathogens, and a less efficient response to antibacterial treatment. Presently, the evidence accumulated in the literature is not sufficient to conclude that the role of antibacterials is only minimal in the management of AOM and that the watchful waiting policy is the most appropriate choice for patients aged <2 years with a certain AOM diagnosis. However, adherence to such a policy in patients with an uncertain or questionable AOM diagnosis and/or mild-to-moderate symptoms, in addition to its implementation in patients aged >2 years, could reduce substantially the use of antibacterials in children and play a major role in the strategy of decreasing antibacterial resistance.

Phenotypic characterization of Streptococcus pneumoniae biofilm development

Streptococcus pneumoniae is among the most common pathogens associated with chronic otitis media with effusion, which has been hypothesized to be a biofilm disease. S. pneumoniae has been shown to form biofilms, however, little is known about the developmental process, the architecture, and the changes that occur upon biofilm development. In the current study we made use of a continuous-culture biofilm system to characterize biofilm development of 14 different S. pneumoniae strains representing at least 10 unique serotypes. The biofilm development process was found to occur in three distinct stages, including initial attachment, cluster formation, and biofilm maturation. While all 14 pneumococcal strains displayed similar developmental stages, the mature biofilm architecture differed significantly among the serotypes tested. Overall, three biofilm architectural groups were detected based on biomass, biofilm thickness, and cluster size. The biofilm viable cell counts and total protein concentration increased steadily over the course of biofilm development, reaching approximately 8 x 10(8) cells and approximately 15 mg of protein per biofilm after 9 days of biofilm growth. Proteomic analysis confirmed the presence of distinct biofilm developmental stages by the detection of multiple phenotypes over the course of biofilm development. The biofilm development process was found to correlate not only with differential production of proteins but also with a dramatic increase in the number of detectable proteins, indicating that biofilm formation by S. pneumoniae may be a far more complex process than previously anticipated. Protein identification revealed that proteins involved in virulence, adhesion, and resistance were more abundant under biofilm growth conditions. A possible role of the identified proteins in biofilm formation is discussed.

The Influence of Mastoidectomy on Natural History of Secretory Otitis Media in Cochlear Implant Children

Secretory otitis media (SOM) is a common childhood disease. The goal of the present study was to determine the influence of mastoidectomy on the incidence of postimplantation SOM in cochlear implant children. We conducted a retrospective study of all the children up to the age of 8 years, who underwent cochlear implantation from 1993 to 2001 in our department. The children were divided into two groups according to the surgical technique used for the implantation: 94 children underwent implantation with the posterior tympanotomy approach (including mastoidectomy) and 48 children were implanted with a suprameatal approach (without mastoidectomy). The incidence of SOM before and after the implantation was compared between the two groups. There were no significant differences between the two study groups in terms of age and the pre- and postimplantation incidence of SOM. Mastoidectomy failed to demonstrate any influence on the natural history of SOM.

Microdialysis studies of the distribution of antibiotics into chinchilla middle ear fluid

For conditions such as acute otitis media, in which antibiotic penetration into middle ear fluid (MEF) may be slow or limited, antibiotic plasma levels may not reflect the concentrations at the site of infection that are relevant to clinical outcome. In such cases, a model is needed that will enable prediction of the time course of unbound, pharmacologically active antibiotic levels in MEF. We describe the use of microdialysis as a sampling tool for measurement of unbound antibiotic concentrations in the MEF of the awake, freely moving chinchilla. Results of studies of MEF penetration of the beta-lactam antibiotic, cefdinir, with use of this technique are also described. Preliminary results of studies of the penetration of antibiotics into MEF of the chinchilla appear consistent with clinical findings and suggest that the chinchilla microdialysis model may prove to be a useful tool for predicting antibiotic efficacy in patients.

Pneumococcal capsular polysaccharides conjugated to protein D for prevention of acute otitis media caused by both Streptococcus pneumoniae and non-typable Haemophilus influenzae: a randomised double-blind efficacy study

BACKGROUND

Acute otitis media is one of the most commonly-diagnosed childhood infections. This study assessed the efficacy of a novel vaccine that contained polysaccharides from 11 different Streptococcus pneumoniae serotypes each conjugated to Haemophilus influenzae-derived protein D in prevention of acute otitis media.

METHODS

4968 infants were randomly assigned to receive either pneumococcal protein D conjugate or hepatitis A vaccine at the ages of 3, 4, 5, and 12-15 months and were followed-up until the end of the second year of life. Middle-ear fluid was obtained for bacteriological culture and serotyping in children who presented with abnormal tympanic membrane or presence of middle-ear effusion, plus two predefined clinical symptoms. The primary endpoint was protective efficacy against the first episode of acute otitis media caused by vaccine pneumococcal serotypes. Analysis was per protocol.

FINDINGS

From 2 weeks after the third dose to 24-27 months of age, 333 clinical episodes of acute otitis media were recorded in the protein D conjugate group (n=2455) and 499 in the control group (n=2452), giving a significant (33.6% [95% CI 20.8-44.3]) reduction in the overall incidence of acute otitis media. Vaccine efficacy was shown for episodes of acute otitis media caused by pneumococcal vaccine serotypes (52.6% [35.0-65.5] for the first episode and 57.6% [41.4-69.3] for any episode). Efficacy was also shown against episodes of acute otitis media caused by non-typable H influenzae (35.3% [1.8-57.4]). The vaccine reduced frequency of infection from vaccine-related cross-reactive pneumococcal serotypes by 65.5%, but did not significantly change the number of episodes caused by other non-vaccine serotypes.

INTERPRETATION

These results confirm that using the H influenzae-derived protein D as a carrier protein for pneumococcal polysaccharides not only allowed protection against pneumococcal otitis, but also against acute otitis media due to non-typable H influenzae. Whether this approach would also allow improved protection against lower respiratory tract infections warrants further investigation.

The chinchilla microdialysis model for the study of antibiotic distribution to middle ear fluid

In cases of slow or limited penetration of an antibiotic to the site of infection such as in acute otitis media (the middle ear), plasma levels of the agent may not reflect the concentrations that are relevant in determining clinical outcome. There is a need for a model that allows prediction of the time-course of unbound, pharmacologically active drug levels in middle ear fluid (MEF). This article introduces microdialysis as a sampling tool to measure unbound antibiotic concentrations in the MEF of the chinchilla, and briefly summarizes the results of studies of MEF penetration of a cephalosporin, a macrolide, and a ketolide antibiotic using this technique. The general concurrence of preliminary results of the chinchilla studies with clinical findings suggests that the chinchilla microdialysis model may be useful in predicting efficacy in patients.

Adherence to therapeutic guidelines for acute otitis media in children younger than 2 years

OBJECTIVES

to analyze adherence to therapeutic guidelines for AOM.

METHODS

Descriptive retrospective study of community primary care providers in southern Israel. Study population (n = 590) included all children aged 0-48 months diagnosed with AOM in PED during the year 2000 who had a referral letter from a community physician and an AOM diagnosis confirmed by tympanocentesis. AOM antibiotic treatment was considered appropriate when in accord with CDC and local therapeutic guidelines.

RESULTS

Referral letter data allowing characterization of AOM by category were available in 471 (79.8%) children, 320 (68%) with simple AOM and 151(32%) with complicated AOM. AOM diagnosis made by the primary care physician was in accord with PED diagnosis in 365/590 (62%) patients. Three hundred and fifty-five (60.2%) patients did not receive antibiotics in the community. Of 365 (62%) children diagnosed with AOM in the community, 235 (64.4%) were treated with antibiotics prior to arrival to PED. Amoxicillin was prescribed to 109 (46.4%), cefuroxime axetil to 48 (20.4%), amoxicillin/clavulanate to 31 (13.2%) and i.m. ceftriaxone to 20 (8.5%) of the patients. Eighty-three (25.9%) patients with simple AOM were treated with antibiotics in the community and only 46 (55.4%) received amoxicillin according to the therapeutic guidelines. Eighty-one (53.6%) patients with complicated AOM were treated with antibiotics in the community and only 41 (50.6%) of them received antibiotics according to AOM therapeutic guidelines. More antibiotics were prescribed in the community to patients with complicated AOM than to patients with simple AOM (81/151, 53.6% versus 83/320, 25.9%, respectively, p < 0.001). Adherence to therapeutic guidelines was similar between the simple and the complicated AOM groups (46/83, 55.4% versus 41/81, 50.6%, respectively, p = 0.5).

CONCLUSION

We found partial adherence to AOM therapeutic guidelines among primary care providers in the community in Southern Israel.

Health-related quality of life in children with otitis media

BACKGROUND

Growing interest in health-related quality of life (HRQoL) in children with otitis media has brought the need to study the currently available HRQoL instruments with respect to their results and their applicability in clinical practice and research of otitis media.

OBJECTIVE

To review existing literature on health-related quality of life research in children with otitis media with respect to: (1) the measured impact of otitis media on HRQoL; and (2) the applicability of HRQoL instruments used in research and clinical practice based on their characteristics and contents.

METHODS

A search was performed in EMBASE (1988-November 2004) and on NLM Gateway (1966-November 2004) for studies assessing health-related quality of life or functional health status by means of disease-specific or generic questionnaires in children aged 0-18 years with chronic or recurrent otitis media with effusion or acute otitis media. The bibliographies of the selected articles were searched manually.

RESULTS

Only 13 of the 141 retrieved articles retrieved fulfilled the criteria for inclusion. In these studies, physical suffering (pain, high fever, etc.), difficulties with hearing or speech, behavioural problems, or emotional distress were reported to be the most important problems experienced by children with otitis media. Almost all instruments applied in these studies measure functional health status instead of health-related quality of life. Data on validity and reliability of these instruments are incomplete.

CONCLUSIONS

Recurrent or chronic otitis media is reported to have a substantial and negative effect on various domains of functional health status and health-related quality of life of children. The OM-6 appears to be the best available instrument to assess functional health status in children with OM in a research setting. However, the lack of true HRQoL instruments as well as incomplete data on their reliability and validity, limit both our current knowledge of HRQoL in OM and the application of current instruments in both research and clinical practice.

Accuracy of acute otitis media diagnosis in community and hospital settings

AIM

To evaluate the accuracy rates of acute otitis media (AOM) diagnosis in the community by analyzing the initial AOM diagnosis (according to information from the referral letters to the Pediatric Emergency Department [PED]) among children with AOM diagnosis confirmed by tympanocentesis at PED.

METHODS

A descriptive, retrospective study conducted during the year 2000, including 590 children aged 0-48 mo diagnosed with AOM at PED. AOM was confirmed by tympanocentesis. We defined: (1) simple AOM as < 3 or < 4 episodes during the last 6 or 12 mo, respectively; (2) complicated AOM as > or = 3 or > or = 4 episodes during the last 6 or 12 mo, respectively, and/or not improving with antibiotics.

RESULTS

571 (96.8%) were < 24 mo of age; 355 (60%) were Arab Bedouins and 235 (40%) Jews. Seventy-three pediatricians, 57 general practitioners and 27 family practitioners provided referral letters. Information on disease severity was available in 471/590 (79.8%) patients, of whom 320 (68%) had simple and 151 (32%) complicated AOM. Three hundred and sixty-five (62%) of 590 patients were accurately diagnosed by referring physicians, more frequently in patients with complicated than simple AOM (p < 0.001). Diagnostic accuracy was similar among physician specialties (p = 0.33) and ethnic groups (p = 0.11). Multivariable logistic regression analysis showed that complicated AOM, adjusted for age, sex, ethnic origin, and physician specialty, was the only predictive factor for accurate AOM diagnosis (odds ratio 4.0, p < 0.001).

CONCLUSIONS

Inaccurate diagnosis of AOM in community settings is common, occurring more frequently in simple than in complicated AOM, and is unrelated to physician specialty and children's ethnicity.

Anaerobes in the upper respiratory tract in infancy

Development of the indigenous microbiota begins on the surfaces of the human body after birth when infants are exposed to continuous person-to-person and environmental contacts with microbes. Anaerobes constitute a significant part of indigenous bacterial communities at different body sites. Pioneering anaerobic commensals are able to colonize and survive in the oral cavity during the first months of life. After teeth emerge, more attachment sites and potential niches are available for anaerobic bacterial colonization. Specific partner relationships influence the composition and stability of forming multigeneric communities, biofilms, where Fusobacterium nucleatum is of specific interest. In infancy, the oral colonization seems to be rather stable at species level, though not at clonal level. The colonization pattern in the nasopharynx is different from that in the oral cavity; anaerobes are absent from healthy nasopharynges but transiently colonize this anatomical site during infection. The most plausible origin for nasopharyngeal anaerobes is the oral cavity and, conceivably, saliva is the most likely transmission vehicle. Whether anaerobic bacteria colonize the nasopharynx just because of ecological changes favoring their growth or whether they could play an active role in the pathogenesis of respiratory infections is not known.

Treatment and outcome of severe and non-severe acute otitis media

To determine outcomes in acute otitis media (AOM) according to severity of disease and to assess different initial treatment regimens, 308 with AOM were enrolled and divided into severe (n = 277; 89.9%) and non-severe (n = 31; 10.1%) groups based on symptoms and tympanic membrane changes. Children in the severe group were initially managed with amoxicillin (AMPC) whereas children in the non-severe group were initially managed without antibiotics. Children were monitored on days 1, 5, 10, 14 and 28. Five outcome measures were assessed: disappearance of symptoms at day 5, resolution of tympanic membrane changes by day 28, disappearance of middle ear effusions by day 28, recurrence of acute symptoms prior to day 28, and need to change treatment regimens. Children with severe disease were more often male (57% versus 36%, P < 0.05) and more often colonized with pathogens (77% versus 55%, P < 0.05 than children with non-severe disease. The two groups were similar with respect to age and day care attendance. Despite differences in initial treatment regimens between the two groups, symptoms improved at the same rate for severe and non-severe disease, 94% by day 5. In contrast, tympanic membranes returned to normal in 69% of the severe and 81% of the non-severe groups by day 28; however, as early as day 5, 10% of the severe and 55% of the non-severe groups demonstrated normal tympanic membranes. Middle ear effusions similarly disappeared more slowly in the severe group, 52% versus 74% by day 14 and 76% versus 84% by day 28. Recurrence rates of acute symptoms occurred with equal frequency in the severe, 15%, and non-severe groups, 10%. Failure of the symptoms or the tympanic membranes to improve led to antibiotic changes in 59.9% of the severe group and to the addition of antibiotics in 51.6% of the non-severe group. Children in the severe group who failed to improve with an initial course of amoxicillin were younger (40.2 months versus 45.8 months, P < 0.05), had higher tympanic membrane scores (4.5 versus 4.1, P < 0.05), and were more often colonized with penicillin-resistant Streptococcus pneumoniae (33.8% versus 6.5%, P < 0.01) than children who responded to AMPC. In a similar manner, children with non-severe disease who failed to improve without antibiotics were younger (40.7 months versus 54.8 months, P < 0.05) and more often colonized with pathogens (75.0% versus 33.4%, P < 0.05).

CONCLUSION

Severe disease occurred more often among males and among children colonized with pathogens. Response to treatment was impaired in younger children and in children colonized with pathogens, especially penicillin-resistant Streptococcus pneumoniae.

Association of early-onset otitis media in infants and exposure to household mould

Otitis media is one of the most common infections of early childhood. Children who first experience acute otitis media at an early age (before 6 months) are at increased risk for recurrent otitis media. This prospective study investigated exposure to measured levels of airborne household mould and the risk of early otitis media in the first 6 months of life among a cohort of infants at high risk for asthma. Between September 1996 and December 1998, women were invited to participate if they had at least one other child with physician-diagnosed asthma. Mothers were given a standardised questionnaire within 4 months of their infant's birth. Airborne mould samples were also taken at this time, and culturable fungi were categorised into four levels according to the report of the Commission of European Communities: 0 (undetectable), 1-499 colony forming units (CFU)/m(3) (low), 500-999 CFU/m(3) (medium), > or =1000 CFU/m(3) (high). Infant respiratory symptoms were collected during quarterly telephone interviews at 6, 9 and 12 months of age. Of the 806 children in the study, 27.8% experienced otitis media before six months of age. Household levels of Penicillium and Cladosporium were modestly associated with the number of otitis media episodes (P = 0.056 and 0.081 respectively). After controlling for potential confounders, Penicillium and Cladosporium were not associated with early otitis media. High levels of 'other' mould (defined as total spore count minus counts for Penicillium, Cladosporium, and yeast) were associated with early otitis media (OR 3.49; 95% CI [1.38, 8.79]). We also found associations between day-care outside of the home and birth during the summer or fall season with early otitis media. This study is suggestive of a relationship between otitis media and mould that warrants further study.

Infant otitis media and the use of secondary heating sources

BACKGROUND

This prospective study investigated the association of exposure to indoor secondary heating sources with otitis media and recurrent otitis media risk in infants.

STUDY DESIGN

We enrolled mothers living in nonsmoking households and delivering babies between 1993 and 1996 in 12 Connecticut and Virginia hospitals. Biweekly telephone interviews during the first year of life assessed diagnoses from doctors' office visits and use of secondary home heating sources, air conditioner use, and day care. Otitis media episodes separated by more than 21 days were considered to be unique episodes. Recurrent otitis media was defined as 4 or more episodes of otitis media. Repeated-measures logistic regression modeling evaluated the association of kerosene heater, fireplace, or wood stove use with otitis media episodes while controlling for potential confounders. Logistic regression evaluated the relation of these secondary heating sources with recurrent otitis media.

RESULTS

None of the secondary heating sources were associated with otitis media or with recurrent otitis media. Otitis media was associated with day care, the winter heating season, birth in the fall, white race, additional children in the home, and a maternal history of allergies in multivariate models. Recurrent otitis media was associated with day care, birth in the fall, white race, and a maternal history of allergies or asthma.

CONCLUSION

We found no evidence that the intermittent use of secondary home heating sources increases the risk of otitis media or recurrent otitis media. This study confirms earlier findings regarding the importance of day care with respect to otitis media risk.

Clonal similarity of salivary and nasopharyngeal Fusobacterium nucleatum in infants with acute otitis media experience

The environment of an infant's nasopharynx during acute otitis media (AOM) favours the growth of anaerobic bacteria, which can be recovered frequently during infection, but hardly at all if the infant is healthy. The aim of this investigation was to identify the potential source and inoculation route of anaerobes that were present in the nasopharynx. Eleven Fusobacterium nucleatum isolates that were collected through the nasal cavity from the nasopharynx of eight infants with a history of AOM, and 161 F. nucleatum isolates from the saliva of the same infants, were typed to the clonal level by using arbitrarily primed PCR (AP-PCR). In five of the eight infants examined, identical AP-PCR types were found among nasopharyngeal and salivary isolates. As anaerobes seem to be present only transiently in the nasopharynx and salivary contamination of the nasopharyngeal samples can be excluded, this observation indicates that the source of nasopharyngeal anaerobes is the oral cavity and that saliva is their transmission vehicle.

Otitis media

Otitis media (OM) continues to be one of the most common childhood infections and is a major cause of morbidity in children. The pathogenesis of OM is multifactorial, involving the adaptive and native immune system, Eustachian-tube dysfunction, viral and bacterial load, and genetic and environmental factors. Initial observation seems to be suitable for many children with OM, but only if appropriate follow-up can be assured. In children younger than 2 years with a certain diagnosis of acute OM, antibiotics are advised. Surgical candidacy depends on associated symptoms, the child's developmental risk, and the anticipated chance of timely spontaneous resolution of the effusion. The recommended approach for surgery is to start with tympanostomy tube placement, eventually followed by adenoidectomy. The ideal intervention for OM, however, does not yet exist, and an urgent need remains to explore new and creative options based on modern insights into the pathophysiology of OM.

Changes in treatment strategies for acute otitis media after full implementation of the pneumococcal seven valent conjugate vaccine

BACKGROUND

Administration of the pneumococcal seven valent conjugate vaccine (PCV-7) results in significant reductions in the incidence of invasive pneumococcal disease and nasopharyngeal colonization rates; however, the reduction in the overall incidence of acute otitis media (AOM) is minimal. Despite an ongoing shortage of PCV-7 in the United States, during which children are receiving fewer doses at longer intervals than the recommended dosing schedule, the incidence of invasive pneumococcal disease in young children has continued to decrease.

PURPOSE

The purpose of this article is to review why the reported effect of PCV-7 on AOM infection rates does not match the reduction in invasive pneumococcal disease or the reduction in nasopharyngeal carriage of Streptococcus pneumoniae.

METHODS

The potential effect of a fully implemented PCV-7 schedule on AOM infections is calculated based on serotype-specific AOM reduction rates observed in clinical studies. Clinical success rates of various antimicrobials used in the treatment of AOM in children fully immunized with PCV-7 also are calculated based on projected PCV-7-induced changes in pathogen profiles and documented antimicrobial resistance rates. Questions regarding potential serotype substitution in children with AOM but not invasive pneumococcal disease, the increased incidence of infection with Haemophilus influenzae in children immunized with PCV-7 and the possibility of herd immunity also will be addressed.

RESULTS

Although the majority of penicillin-nonsusceptible S. pneumoniae are included in PCV-7, AOM caused by these strains will not completely disappear, especially in children 24 months of age and younger.

CONCLUSIONS

Consequently, clinicians must continue to consider penicillin-nonsusceptible pneumococci when prescribing antimicrobials for AOM.

Clinical considerations in the diagnosis of otitis media

Acute otitis media and otitis media with effusion are commonly encountered by both general practitioners and specialists. The diagnosis of otitis media requires a focused history and accurate physical examination. Unfortunately, many practitioners are either unaware of the criteria needed to make the diagnosis, or they incorrectly perform or misinterpret the physical examination. We review the pertinent historical and physical examination findings needed to accurately diagnose otitis media. Additionally, we examine the accessory tests that might help make the correct diagnosis in difficult cases. Finally, we address the issues involved in ensuring that both current and future physicians are appropriately trained in the diagnosis of this common illness.