Interaction between middle and inner ears in otitis media

Pan-serotype Reduction in Progression of Streptococcus pneumoniae to Otitis Media After Rollout of Pneumococcal Conjugate Vaccines

Background

Reductions in otitis media (OM) burden following rollout of pneumococcal conjugate vaccines (PCVs) have exceeded predictions of vaccine impact. In settings with active surveillance, reductions in OM caused by vaccine-targeted pneumococcal serotypes have co-occurred with reductions in OM caused by other pathogens carried in the upper-respiratory tract of children. To understand these changes, we investigated the progression of vaccine-targeted and non-vaccine pneumococcal serotypes from carriage to OM before and after vaccine rollout.

Methods

Nasopharyngeal carriage prevalence of pneumococcus was monitored in prospective studies of Bedouin and Jewish children <3 years old in southern Israel between 2004 and 2016. Incidence of OM necessitating middle-ear fluid culture (predominantly complex OM including recurrent, spontaneously-draining, non-responsive, and chronic cases) was monitored via prospective, population-based active surveillance. We estimated rates of pneumococcal serotype-specific progression from carriage to disease before and after rollout of PCV7/13, measured as OM incidence per carrier. We pooled serotype-specific estimates using Bayesian random-effects models.

Results

On average, rates of progression declined 92% (95% credible interval: 79-97%) and 80% (46-93%) for PCV7/13 serotypes among Bedouin and Jewish children <12 months old, respectively, and 32% (-58-71%) and 61% (-5-86%) among children aged 12-35m. For non-vaccine serotypes, rates of progression among Bedouin and Jewish children aged <12m declined 74% (55-85%) and 43% (4-68%), respectively.

Conclusions

Vaccine-targeted and non-vaccine pneumococcal serotypes showed lower rates of progression to complex OM after rollout of PCV7/13. Early-life OM episodes historically associated with vaccine-serotype pneumococci may impact the susceptibility of children to OM progression.

Prevention of early episodes of otitis media by pneumococcal vaccines might reduce progression to complex disease

Otitis media is a common childhood infection of the middle ear and a major cause of morbidity. This multifactorial disease manifests as a spectrum of clinical syndromes from uncomplicated acute otitis media to more complex recurrent and chronic cases (frequently polymicrobial), with the major pathogens involved being Streptococcus pneumoniae and non-typeable Haemophilus influenzae. Pneumococcal conjugate vaccines (PCVs) target only a few serotypes that cause otitis media; however, results from studies suggest that existing PCVs can prevent early episodes of disease associated with vaccine serotypes, resulting in a reduction of subsequent complex cases caused by non-vaccine serotypes and other otopathogens, which contribute considerably to the disease burden. In this Review, we discuss the role of pneumococcus in the disease continuum and assess clinical evidence showing the effect of prevention of early episodes on the complex interplay between bacterial species implicated in otitis media.

Evaluation of vestibular function in patients with chronic suppurative otitis media

OBJECTIVE

The objective of this study was to assess vestibular functions in patients with chronic suppurative otitis media (CSOM) with and without sensorineural hearing loss.

STUDY DESIGN

This was a prospective case study performed at a tertiary referral university hospital. Sixty patients with CSOM were included, and patients with a history of head trauma, diabetes, hypertension, previous ear surgery, use of ototoxic drugs, neurological deficits and suspected fistulae were excluded.

PATIENTS AND METHODS

The patients underwent basic audiological evaluation, and clinical and instrumental vestibular evaluation. The incidence and extent of vestibular dysfunction in patients with CSOM were analyzed.

RESULTS

A total of 42 males and 16 females with a mean age of 29.5 years were included in this study. Forty ears had tubotympanic disease and 19 had cholesteatoma. There were 14 ears with sensorineural hearing loss. A positive history of vertigo was reported in 53.5% of the cases. Rotatory chair abnormalities were found in 70% of the cases, caloric hypofunction was found in 61.6%, and vestibular myogenic evoked potentials were abnormal in 25%. The only positive correlation with vestibular dysfunction was the duration of disease.

CONCLUSIONS

The vestibular system is significantly affected in cases with CSOM. Both semicircular canals and the saccule are affected. All patients with long-standing CSOM should be evaluated for vestibular dysfunction irrespective of their hearing levels.

Predisposing factors for inner ear hearing loss association with chronic otitis media

The aim of the present study was to investigate the consequences of chronic otitis media on inner ear function. Retrospective analysis of conventional pure-tone audiometry tests was carried out on 344 patients who were scheduled for surgical treatment of unilateral chronic otitis media without other risk factors for sensorineural hearing loss. Bone conduction thresholds of diseased ears were compared with those of contralateral, non-diseased ears. Selected clinical features were assessed among diseased ears to examine possible influences on inner ear function. Mean bone conduction threshold differences varied from 0.6 dB at 0.5 kHz to 3.7 dB at 4 kHz. These differences augmented with increasing duration of middle ear disease. Impaired hearing by bone conduction thresholds of diseased ears correlated with increased age at every frequency and with an interruption of the ossicular chain only at higher frequencies. The severity of sensorineural hearing loss correlated with longer duration of middle ear disease. Thus, surgical treatment of dry and apparently stable tympanic membrane perforation is warranted.