The effect of pneumococcal conjugate vaccines on incidence and microbiology associated with complicated acute otitis media.

OBJECTIVES: The objectives of this study were to investigate the incidence of complicated acute otitis media (cAOM) as well as the associated microbiology before and after introduction of the 7- and 13-valent pneumococcal conjugate vaccines (PCV-7 and -13), respectively. CAOM comprises "heavy" AOM (AOM demanding hospitalization), mastodismus (M) and acute mastoiditis (AM). METHODS: A retrospective cohort study of the incidence and microbiology associated with cAOM during the non-PCV era, the PCV-7 and 13 eras, respectively. Clinical and microbiological data were prospectively registered in a local database. The incidences of cAOM as well as the distribution of various bacterial strains in the three eras were compared. RESULTS: A total of 246 cases of cAOM (125 in the pre-vaccine period (2001-2006), 50 in the PCV-7 period (2007-2010) and 71 in the PCV-13 period (2011-2015)) were identified. The incidence of hAOM decreased by 62% in the PCV7-era but increased to almost pre-vaccine levels in the PCV-13 era. In the M + AM group, a decrease by almost 21% in the PCV7-era was found compared to the pre vaccine era, whereas the decrease was only 12% in the PCV13-era. The three most common findings in both hAOM and M + AM were Streptococcus pneumonia (SP), group A streptococcus (GAS) and "no growth". In the hAOM group, SP decreased from 38% in the pre-vaccine era to 31% in the PCV7-era and further to 16% in the PCV13-era. GAS decreased from 17% in the pre-vaccine era to 0% in the PCV7-era and 16% in the PCV13-era. The percentage of "no growth" increased from 12% to 38% and 44%, respectively. In the M + AM group, SP decreased to 10% in the PCV13-era compared with 44% in the pre-vaccine era and 41% in the PCV7-era. An increase in GAS from 15% in the pre-vaccine era and PCV7-era to 30% in the PCV13-era was observed. The "no growth" percentage increased from 13% in the pre-vaccine era to 26% in the PCV7-era and 33% in the PCV13-era. CONCLUSION: Introduction of PCV7 and PCV13 has been associated with an overall reduction of cAOM in Central Region Denmark. Pneumococci were still one of the two most common bacteria species related to cAOM though a decrease in pneumococci positive cases was observed. We found an increase in M + AM induced by GAS and a relatively large increase in "no growth", which might be caused by a more aggressive pre-hospital approach to treatment with antibiotics. Consequently, it is not evident whether the reduction of incidences is caused by the vaccines or a more aggressive antimicrobial attitude to manage AOM. The shift to GAS from SP is worrisome, and therefore continuous surveillance of the microbiology associated with AOM is warranted.

Incidence, 10-year recidivism rate and prognostic factors for cholesteatoma.

OBJECTIVE: Cholesteatoma patients have a high risk of recurrence with complications, and knowledge exchange is a prerequisite for improving treatment. This study aimed to apply appropriate statistics to provide meaningful and transferable results from cholesteatoma surgery, to highlight independent prognostic factors, and to assess the incidence rate. METHODS: Incidence rates were assessed for the district of Aarhus, Denmark. From 147 patients operated on mainly with canal wall up mastoidectomies for debuting cholesteatomas, 10-year Kaplan-Meier recidivism rates were calculated and independent prognostic factors for the recidivism were identified by Cox multivariate regression analyses. RESULTS: Incidence rate was 6.8 per 100 000 per year. The 10-year cumulative recidivism rate was 0.44 (95 per cent confidence interval, 0.37-0.53). Independent prognostic factors for the recidivism were: age below 15 years (hazard ratio = 2.2; p > z = 0.002), cholesteatoma localised to the mastoid (hazard ratio = 1.7; p > z = 0.04), stapes erosion (hazard ratio = 1.9; p > z = 0.02) and incus erosion (hazard ratio = 1.9; p > z = 0.04). CONCLUSION: The recidivism rate is influenced by several factors that are important to observe, both in the clinic and when comparing results from surgery.

Brain fingerprints of olfaction: a novel structural method for assessing olfactory cortical networks in health and disease.

Olfactory deficits are a common (often prodromal) symptom of neurodegenerative or psychiatric disorders. As such, olfaction could have great potential as an early biomarker of disease, for example using neuroimaging to investigate the breakdown of structural connectivity profile of the primary olfactory networks. We investigated the suitability for this purpose in two existing neuroimaging maps of olfactory networks. We found problems with both existing neuroimaging maps in terms of their structural connectivity to known secondary olfactory networks. Based on these findings, we were able to merge the existing maps to a new template map of olfactory networks with connections to all key secondary olfactory networks. We introduce a new method that combines diffusion tensor imaging with probabilistic tractography and pattern recognition techniques. This method can obtain comprehensive and reliable fingerprints of the structural connectivity underlying the neural processing of olfactory stimuli in normosmic adults. Combining the novel proposed method for structural fingerprinting with the template map of olfactory networks has great potential to be used for future neuroimaging investigations of olfactory function in disease. With time, the proposed method may even come to serve as structural biomarker for early detection of disease.

Pre- and post-operative dizziness, tinnitus, and taste disturbances among cochlear implant recipients.

OBJECTIVE: To determine the pre- and post-operative prevalence of dizziness, tinnitus and taste disturbances in adult cochlear implant recipients. METHODS: A questionnaire regarding pre- and post-operative dizziness, tinnitus and taste disturbances was sent to 170 cochlear implant recipients implanted between January 2003 and March 2009. Seventy-seven patients (41 per cent) responded. RESULTS: Pre-operatively, 20 per cent of the participants experienced dizziness, 52 per cent experienced tinnitus and 3 per cent experienced taste disturbances. Post-operative dizziness developed in 46 per cent of patients and resolved in the majority of these; however, 15 per cent reported dizziness more than six months after implantation. Tinnitus worsened in 25 per cent of patients, whereas 73 per cent reported attenuation or termination of tinnitus. Post-operatively, tinnitus developed in 12 per cent and taste disturbances developed in 17 per cent of the patients. CONCLUSION: The high prevalence of dizziness, tinnitus and taste disturbances reported by cochlear implant recipients necessitates that assessment of symptoms related to inner ear and chorda tympani damage are included when evaluating operative results.

Cognitive and outcome measures seem suboptimal in children with cochlear implants - a cross-sectional study.

OBJECTIVE: This study investigates whether cognition as a single variable significantly influences the hearing and speech outcomes of children with cochlear implants (CIs). More specifically, it identifies various types of cognitive disorders among children with CI, comparing these children's cognitive abilities to the outcomes of CI in terms of hearing and speech performance. STUDY DESIGN: Cross-sectional cognitive testing of children with CIs. SETTING: West Danish CI Centre, Aarhus University Hospital, Denmark. MATERIALS AND METHODS: Fifty-eight CI children underwent postoperative cognitive evaluation. Cognitive tests included Bayley Scales of Infant Development (Bayley-III), Snijders-Oomen Nonverbal Intelligence Test Revised (SON-R) and Wechsler Intelligence Scale for Children, Fourth Edition (WISC-IV), depending on the age of the child. Outcome measures of hearing and speech capacity after CI consisted of Categories of Auditory Performance (CAP), Speech Intelligibility Rating (SIR) and Peabody Picture Vocabulary Test-4 (PPVT-4). RESULTS: Only PPVT-4 correlated significantly with cognition scores. Over time, the value of CAP and SIR seems limited by a pronounced ceiling effect. CONCLUSION: The most widely used outcome tests after CI, that is CAP and SIR, may not reflect cognitive disabilities sufficiently due to pronounced ceiling effects. International guidelines suggesting a panel of robust age-matched tests are warranted to optimise rehabilitation programmes as well as the counselling of parents.

A systematic review of Fusobacterium necrophorum-positive acute tonsillitis: prevalence, methods of detection, patient characteristics, and the usefulness of the Centor score.

The purpose of this study was to review the current evidence for an association between Fusobacterium necrophorum (FN) and acute tonsillitis (AT), to assess the prevalence of FN in AT, to identify the better FN detection method, and to characterize the clinical characteristics of FN-positive patients with uncomplicated AT. A systematic literature search was conducted in the PubMed, EMBASE, and SweMed+ databases for studies reporting on the recovery rates of FN in patients with AT. A total of 498 unique records were identified. Eleven studies were included in a qualitative synthesis and six studies were included in a meta-analysis. Considerable heterogeneity (I2 = 60 %) and risk of bias and confounders was found among the studies, though a subset of studies (prospective) had lower heterogeneity and higher study quality. FN was recovered significantly more frequently from patients (21.2 %) compared to healthy controls (7.6 %) (p < 0.001). FN recovery rates were similar between culture-based studies (20.3 %) and studies using polymerase chain reaction (PCR) methodology (22.2 %) (p = 0.462). The typical FN-positive AT patient was a smoking young (15-25 years) male presenting with tonsillar exudates and a Centor score of 2 or higher. A clear association between FN and AT was found. FN is likely to be a significant and prevalent pathogen in AT, especially in teenagers and young adults. However, no evidence for causality between FN and AT has been established and it is unexplored if timely antibiotic therapy directed against FN accelerates the resolution of symptoms and decreases the risk of complications.

Olfactory screening: validation of Sniffin' Sticks in Denmark.

OBJECTIVES: The Sniffin' Sticks 12-identification test (SIT-12) is the most commonly applied Danish olfaction screening tool; however, it has never been validated in a Danish population. The screening score depends on familiarity with descriptors, which is strongly influenced by linguistic and cultural factors, why validation is mandatory. This study aimed to validate the SIT-12 in a Danish population. DESIGN: Prospective controlled study. SETTING: Otorhinolaryngology department. PARTICIPANTS: The SIT-12 was applied to 100 normosmic, healthy adult Danish participants. MAIN OUTCOME MEASURES: Choice of descriptors was registered, along with nasal endoscopic examination, screening for cognitive impairment, depression and sinonasal symptoms. Descriptors of the original version of SIT-12 were evaluated in 50 participants, and misleading descriptors were identified. Modifications to these descriptors were subsequently validated in a comparable group of 50 participants. RESULTS: Mean odorant identification score in the evaluation group was 11.0 of a possible 12, and 11.6 in the validation group (P < 0.0001). Among all odorant identification errors in the evaluation group, 60% were due to two incorrect descriptors having close resemblance to the correct descriptors, lemon and cinnamon. Two additional descriptors were unfamiliar to more than half the participants. There was a significant difference in the distribution of wrong identification answers between odorants in the evaluation group (P < 0.001), but not in the validation group. CONCLUSIONS: The identified systematically wrong descriptors have been modified and validated in the Danish SIT-12.

Prevalence of tonsillar human papillomavirus infections in Denmark.

The incidence of tonsillar carcinomas associated with Human Papillomavirus (HPV) infection has increased dramatically over the last three decades. In fact, currently in Scandinavia, HPV-associated cases account for over 80 % of tonsillar carcinoma cases. Yet, the epidemiology and natural history of tonsillar HPV infections remains poorly characterized. Our aim was to characterize such infections in the Danish population in tumor-free tonsillar tissue. Unlike previous studies, we considered both palatine tonsils. We examined both tonsils from 80 patients with peritonsillar abscess (n = 25) or chronic tonsillar disease (n = 55). HPV was detected by nested PCR with PGMY 09/11 and GP5+/GP6+L1 consensus primers, and typed by sequencing. Samples were also analyzed using a higher-throughput method, the CLART HPV 2 Clinical Array Assay. The overall prevalence of HPV tonsillar infection was 1.25 % (1/80, 95 % CI 0.03-6.77 %) by nested PCR, and 0 % by CLART HPV2 Clinical Array. The HPV-positive patient was a 16-year-old female with recurrent tonsillitis and tonsillar hypertrophy. The type detected was HPV6. HPV was not detected in the contralateral tonsil of this patient. Compared to cervical HPV infections in Denmark, tonsillar HPV infections are 10- to 15-fold less frequent. In the HPV-positive patient in this study, HPV was detected in only one of the tonsils. This raises the possibility that prior studies may underestimate the prevalence of HPV infections, as they do not consider both palatine tonsils.

Antibody development to Fusobacterium necrophorum in patients with peritonsillar abscess.

A polymicrobial mixture of aerobic and anaerobic bacteria is commonly recovered from peritonsillar abscess (PTA) aspirates. Previous studies have suggested a role for Fusobacterium necrophorum (FN) in the development of PTA. The purpose of the current study was to explore whether anti-FN antibodies were produced in patients with PTA. We developed a novel immunofluorescence-based method to measure anti-FN antibody levels in acute and convalescent sera from 15 patients with PTA and 47 patients with chronic tonsillar conditions (controls) undergoing acute or elective tonsillectomy, respectively. Bacterial cultures were performed on tonsillar cores and surfaces, pus aspirates, and blood. An increase in anti-FN antibody levels (of at least doubling of the previous level) was observed in 8 of 11 (73 %) PTA patients with FN-positive pus aspirate cultures (FN-positive patients). In contrast, the four FN-negative PTA patients did not have an increase in anti-FN antibody levels (p = 0.026). The change in anti-FN antibody levels in FN-positive PTA patients was also significantly greater than that for FN-positive electively tonsillectomized patients (p = 0.0014) and all electively tonsillectomized patients (p < 0.001). Our results validate FN as a significant and prevalent pathogen in PTA. This finding has implications for the diagnostic work-up of PTA and may also have implications for the treatment of acute tonsillitis.

Staphylococcus aureus is a major pathogen in severe acute bacterial rhinosinusitis.

PURPOSE: The purpose of this study was to investigate the epidemiology and microbiology of severe acute bacterial rhinosinusitis in patients admitted to a Danish tertiary hospital. METHODS: A retrospective study was performed including all cases of acute rhinosinusitis admitted to the ENT-department of Aarhus University Hospital, in the period 2001 to 2011. RESULTS: In total, 143 cases of acute rhinosinusitis were identified of which 51% were children. The most prevalent bacterial strains were Staphylococcus aureus followed by group A streptococcus, Haemophilus influenzae and Streptococcus pneumonia. Morexella catarrhalis was only rarely cultured. Anerobes were not assessed routinely. Of all patients, 47.8% presented with orbital complications and 2.1% developed intracranial complications. Patients infected with group A streptococcus had significantly higher leukocyte and neutrophil counts than other patients. All cultured S. aureus were resistant to penicillin, but sensitive to methicillin. CONCLUSION: Our results imply that S. aureus and group A streptococcus are important pathogens in severe and complex cases of ABRS, in addition to the accepted pathogens S. pneumoniae and H. influenzae. On the contrary M. catarrhalis appears less significant. These findings have important implications regarding the selection of relevant treatment strategy in secondary care, which may currently be underestimating the role of S. aureus.

The role of viruses in the pathogenesis of peritonsillar abscess.

Peritonsillar abscess (PTA) is the most frequent complication of acute tonsillitis and a prevalent cause for acute admission to otorhinolaryngology departments. Our aim was to examine the role of viruses in the pathogenesis of PTA, as this has not previously been considered. We examined both palatine tonsils from 25 patients undergoing acute tonsillectomy for PTA, using PCR-based assays for herpes simplex virus-1 and -2 (HSV-1 and -2), adenovirus, Epstein-Barr virus (EBV), influenza A and B, and respiratory syncytial virus (RSV) A and B. We similarly examined tonsils from 55 patients undergoing elective tonsillectomy due to chronic tonsillar conditions. These patients served as a control group, as they did not have a clinically apparent infection at the time of surgery. Only HSV-1 (5/80, 6.3%), adenovirus (11/80, 13.8%), and EBV (71/80, 88.8%) were detected in our study population. There was no statistically significant difference in the frequency of these viruses across different diagnostic groups. Quantification of EBV load demonstrated no differences between the PTA and the elective tonsillectomy group, nor between the abscessed and non-abscessed tonsil of PTA patients. In summary, our data do not support a significant role for the examined viruses in the pathogenesis of PTA.

Significant pathogens in peritonsillar abscesses.

Peritonsillar abscesses (PTA) are polymicrobial infections, with a diverse aerobic and anaerobic flora. The aim of the present study is to compare bacteriologic culture results from patients with PTA to those from patients undergoing elective tonsillectomy (clinically non-infected tonsils), to better elucidate the pathogenic significance of various isolates. A prospective study was conducted on 36 PTA patients undergoing acute tonsillectomy and on 80 electively tonsillectomised patients. Fusobacterium necrophorum (FN) and Streptococcus group A (GAS) were isolated significantly more frequently from the tonsillar cores of PTA patients, from both the abscessed (p = 0.001 and p = 0.046, respectively) and non-abscessed sides (p < 0.001 and p = 0.046, respectively), than from the tonsillar cores of electively tonsillectomised patients. Our findings indicate that FN and GAS are the prominent pathogens in PTA. In patients with PTA, the incidence of FN and GAS isolated from the abscessed tonsil was the same as from the non-abscessed contralateral side, and the growth was comparable by a semi-quantitative approach. Our findings suggest that FN is also of pathogenic importance in acute tonsillitis, and that FN growth is not a subsequent phenomenon once an abscess has formed. Our findings further suggest that other factors influence the development of PTA.

An overview of the microbiology of acute ear, nose and throat infections requiring hospitalisation.

This study is the first to provide an extensive overview of the microbiology of acute ear, nose and throat infections requiring hospitalisation. All 2,028 cases of acute infections admitted between 1 January 2001 and 31 December 2006 were reviewed to assess the use of pre-admission antibiotics, microbiological results, antibiotic and surgical management and length of hospitalisation. Infections of the oropharynx accounted for the vast majority of admissions, followed by ear infections, and cutaneous neck abscesses. Peritonsillar abscess was the most frequent diagnosis, accounting for over one third of admissions (39.8%, 808 out of 2,028). Complete microbiological data were available for 1,430 cultures, and were analysed for trends with respect to diagnosis, age, gender and use of pre-admission antibiotics. Forty-six percent (657 out of 1,430) of cultures yielded no growth or normal flora. This value increased to 77.0% (298 out of 387) in patients with pre-admission antibiotics. The distribution of microbiological isolates varied significantly between patients with and without pre-admission antibiotics, as well as with respect to age and gender. The most frequently isolated bacteria were Group A Streptococcus (13.7%, 196 out of 1,430), Fusobacterium necrophorum (13.6%, 195 out of 1,428) and Staphylococcus aureus (8.0%, 114 out of 1,430). Fusobacterium necrophorum was primarily isolated from cases of peritonsillar abscess (90.8%, 177 out of 195). This study suggests that F. necrophorum is a far more widespread pathogen in otorhinolaryngology than previously reported, and questions the value of routine culturing, as results rarely altered initial treatment. Further research on the microbiological variations with age and gender is recommended to better target culturing and treatment, and enhance our understanding of the pathogenesis of ear, nose and throat infections.

Post-operative problems and complications in 313 consecutive cochlear implantations.

OBJECTIVE: To describe problems and complications associated with cochlear implantation, and their management, in a Danish patient population comprising both paediatric and adult patients. DESIGN: Retrospective chart review. SETTING: Tertiary referral centre. SUBJECTS: Three hundred and thirteen consecutive cochlear implantations were studied. The median age of the study population was 10 years. Sixty per cent of patients were children and 40 per cent were adult; 52 per cent were female and 48 per cent were male. INTERVENTION: Two hundred and ninety-four patients received a Cochlear Nucleus implant. The remaining 19 received an Advanced Bionics implant. MAIN OUTCOME MEASURE: Presence of problems and complications after cochlear implantation. RESULTS: Post-operative complications were found in 15.7 per cent of patients. The majority of these complications (11.2 per cent) were minor; 4.5 per cent were major. The major complications included one patient with meningitis, one patient with multiple antibiotic resistant Staphylococcus aureus infection of a radical cavity, and one diabetic patient who developed a severe skin infection and whose implant became exposed. CONCLUSION: Cochlear implantation is a safe procedure within the studied setting. However, it is essential that careful attention be paid to surgical planning and technique, and it is important that healthcare staff and patients be aware of the possible problems and complications.

Grommets (ventilation tubes) for hearing loss associated with otitis media with effusion in children.

BACKGROUND: Otitis media with effusion (OME), or 'glue ear', is very common in children, especially between the ages of one and three years with a prevalence of 10% to 30% and a cumulative incidence of 80% at the age of four years. OME is defined as middle ear effusion without signs or symptoms of an acute infection. OME may occur as a primary disorder or as a sequel to acute otitis media. The functional effect of OME is a conductive hearing level of about 25 to 30 dB associated with fluid in the middle ear. Both the high incidence and the high rate of spontaneous resolution suggest that the presence of OME is a natural phenomenon, its presence at some stage in childhood being a normal finding. Notwithstanding this, some children with OME may go on to develop chronic otitis media with structural changes (tympanic membrane retraction pockets, erosion of portions of the ossicular chain and cholesteatoma), language delays and behavioural problems. It remains uncertain whether or not any of these findings are direct consequences of OME. The most common medical treatment options include the use of decongestants, mucolytics, steroids, antihistamines and antibiotics. The effectiveness of these therapies has not been established. Surgical treatment options include grommet (ventilation or tympanostomy tube) insertion, adenoidectomy or both. Opinions regarding the risks and benefits of grommet insertion vary greatly. The management of OME therefore remains controversial. OBJECTIVES: To assess the effectiveness of grommet insertion compared with myringotomy or non-surgical treatment in children with OME. The outcomes studied were (i) hearing level, (ii) duration of middle ear effusion, (iii) well-being (quality of life) and (iv) prevention of developmental sequelae possibly attributable to the hearing loss (for example, impairment in impressive and expressive language development (measured using standardised tests), verbal intelligence, and behaviour). SEARCH STRATEGY: We searched the Cochrane Central Register of Controlled Trials (CENTRAL) (The Cochrane Library Issue 1, 2003), MEDLINE (1966 to 2003), EMBASE (1973 to 2003) and reference lists of all identified studies. The date of the last systematic search was March 2003, and personal non-systematic searches have been performed up to August 2004. SELECTION CRITERIA: Randomised controlled trials (RCTs) evaluating the effect of grommets on hearing, duration of effusion, development of language, cognition, behaviour or quality of life. Only studies using common types of grommets (mean function time of 6 to 12 months) were included. DATA COLLECTION AND ANALYSIS: Data from studies were extracted by two reviewers and checked by the other reviewers. MAIN RESULTS: Children treated with grommets spent 32% less time (95% confidence interval (CI) 17% to 48%) with effusion during the first year of follow-up. Treatment with grommets improved hearing levels, especially during the first six months. In the randomised controlled trials that studied the effect of grommet insertion alone, the mean hearing levels improved by around 9 dB (95% CI 4 dB to 14 dB) after the first six months, and 6 dB (95% CI 3 dB to 9 dB) after 12 months. In the randomised controlled trials that studied the combined effect of grommets and adenoidectomy, the additional effect of the grommets on hearing levels was improvement by 3 to 4 dB (95% CI 2 dB to 5 dB) at six months and about 1 to 2 dB (95% CI 0 dB to 3 dB) at 12 months. Ears treated with grommets had an additional risk for tympanosclerosis of 0.33 (95% CI 0.21 to 0.45) one to five years later. In otherwise healthy children with long-standing OME and hearing loss, early insertion of grommets had no effect on language development or cognition. One randomised controlled trial in children with OME more than nine months, hearing loss and disruptions to speech, language, learning or behaviour showed a very marginal effect of grommets on comprehensive language. AUTHORS' CONCLUSIONS: The benefits of grommets in children appear small. The effect of grommets on hearing diminished during the first year. Potentially adverse effects on the tympanic membrane are common after grommet insertion. Therefore an initial period of watchful waiting seems to be an appropriate management strategy for most children with OME. As no evidence is yet available for the subgroups of children with speech or language delays, behavioural and learning problems or children with defined clinical syndromes (generally excluded from the primary studies included in this review), the clinician will need to make decisions regarding treatment for such children based on other evidence and indications of disability related to hearing impairment. This review does not resolve the discrepancy between parental and clinical observation of a beneficial treatment effect and the results in the reviewed RCT showing only a short-term effect on hearing and virtually no effect on development. Is the perceived, often dramatic, effect of grommets only a short-term one? Are some children more sensitive to OME-related hearing loss than others? If so, how do we identify them?Further research should focus upon indications. Studies should use sufficiently large sample sizes to show significant interactions. There is a need to determine the most suitable variables and appropriate "softer" outcomes to be the subject of these interaction tests. Interesting options include measures of speech-in-noise and binaural hearing. The generally modest results in the trials which are included in this review should make it easier to justify randomisation of more severely affected and higher-risk children in appropriately constructed trials. Randomised controlled trials are necessary in these children before more detailed conclusions about the effectiveness of grommets can be drawn.

NF-kappaB in cultivated middle ear epithelium.

OBJECTIVE: Otitis media with effusion (OME) may develop into a chronic course in some patients. In the majority of cases lipopolysaccharide (LPS) is detected in the middle ear fluid being capable of initiating and maintaining the inflammatory process associated with the disease. In addition, various extracellular signs of the inflammatory cascade are present, such as cytokines and ICAM-1 receptors. However, the underlying regulatory mechanisms situated intracellularily are sparsely recognized. NF-kappaB is a ubiquitously transcription factor complexed to its inhibitor within the cytoplasm. In response to stimuli, e.g. LPS or cytokines, NF-kappaB becomes activated and is translocated to the nucleus. At this level it induces transcription of various genes and subsequent expression of mRNA encoding for many immunoglobulins and cytokines, e.g. interleukin 8 (IL-8) which may be responsible for prolonging and maintaining the inflammatory process. METHODS: To evaluate if NF-kappaB is present in middle ear epithelium including to identify possible stimulating factors in vitro studies using rabbit middle ear epithelial cells (meec) were undertaken. Both normal cells and LPS exposed cells were studied. ELISA techniques were applied to detect NF-kappaB, ICAM-1 receptors and IL-8. All measurements were adjusted to the concentration of total cell protein (TP). RESULTS: NF-kappaB was detected in the normal middle ear epithelium in concentrations between 16.8 and 28.6 ng/microg TP. In response to LPS the NF-kappaB content increased with 25-33%. This enhancement became more pronounced with longer duration of the LPS exposition. A relatively distinct expression of ICAM-1 preceded the NF-kappaB increase, after which the ICAM-1 measurements declined. IL-8 was hardly measurable in normal cells. The IL-8 concentrations were higher in LPS exposed cultures. The time related curve demonstrated a diphasic shape with an early and a late maximum. CONCLUSION: The chronic inflammation seen in some OME patients may be due to LPS activating ICAM-1 receptors and NF-kappaB followed by release of IL-8. An autocrine pathway may be established through activation of TNF alpha and IL-1beta. Thus, elucidation of alternative pathways in the inflammatory cascade and elimination of LPS, alternatively inhibition of NF-kappaB and/or IL-8, should be an issue for future investigation.

Induction of mucin and adhesion molecules in middle ear mucosa.

We hypothesized that inflammation molecules induce the secretory hyperplasia characteristic of otitis media with effusion (OME). The purpose of the present study was to compare the location of inflammation molecules and mucin in the middle ear mucosa of both normal and OME ears. OME was created by bisection of the tensor veli palatini muscle in germ-free rabbits, and the development of middle ear effusion was confirmed by otomicroscopy and tympanometry. Ventilation tubes (VTs) were inserted in half of the ears. The animals were decapitated after 8 weeks, and serial sections of the middle ear mucosae were either periodic acid-Schiff (PAS)-stained or stained immunohistochemically for inflammation molecules or mucins. The length of stained epithelium was measured and related to the total epithelial length. There was a striking resemblance between mucin-type MUC5B- and PAS-positive epithelium and areas positive for the chemoattractant inflammation molecules intercellular adhesion molecule-1 (ICAM-1) and RANTES (reacted upon activation, normal T expressed and secreted). The percentages of ICAM-1- and PAS-stained epithelium were significantly higher in OME ears than in normal ears. OME ears treated with VTs also contained significantly more PAS-positive epithelium than normal ears, but less than OME ears. Based on the spatial and temporal coincidence between ICAM-1 and mucin, it is suggested that: (i) inflammation may initiate and maintain the hypersecretory state of the middle ear mucosa which is presumably responsible for the chronicity of OME; and (ii) that MUC5B is a major mucin component of OME effusions.

RANTES in otitis media with effusion: presence, role and correlation with cytokines and microbiology.

Various inflammatory cells and cytokines have been identified in otitis media with effusion (OME). The presence of neutrophils has been linked to interleukin-8, but no chemotactic factor has as yet been identified for monocytes. The chemokine RANTES (Regulated upon Activation, Normal T Expressed and Secreted) attracts and activates primarily monocytes and may contribute to the pathogenesis of middle ear inflammation. We investigated the presence of RANTES by: 1) ELISA measurement in 114 middle ear effusions from children suffering from OME, 2) immunohistochemical localisation in experimental OME rabbit middle ear mucosa, and 3) expression in cultured rabbit middle ear epithelium in response to proinflammatory stimuli. RANTES was detectable in 94 (82%) of 114 effusions with a median concentration of 79.7 pg/mg total protein content. The concentration of RANTES was positively correlated with the endotoxin content. Immunohistochemically, RANTES was localized to the epithelial layer in experimental OME. In vitro, RANTES was expressed in middle ear epithelium in response to proinflammatory stimuli (TNF-alpha) in a dose-dependent manner. The expression of RANTES may explain the recruitment of monocytes in OME, possibly as a result of TNF-alpha-mediated endotoxin stimulation.

How does endotoxin trigger inflammation in otitis media with effusion?

OBJECTIVES: The relationship among microorganisms, endotoxin, and inflammatory mediators in otitis media with effusion (OME) was examined. STUDY DESIGN: Analysis of 152 middle ear effusions aspirated at the time of ventilation tube insertion from children with OME. METHODS: Effusion samples were cultured for pathogenic bacteria The two primary cytokines, interleukin-1beta (IL1beta) and tumor necrosis factor (TNFalpha), and the adhesion molecules, intercellular and vascular adhesion molecule (ICAM-1 and VCAM-1), were quantified using the enzyme-linked immunosorbent assay (ELISA) technique. Endotoxin concentration was measured with a limulus amebocyte lysate assay, and total protein concentration was quantified using the Biorad microassay. RESULTS: The cultures of pathogenic bacteria were positive in 33 of the 152 effusions (22%), which contained more endotoxin and more of the primary cytokines than the 119 culture-negative effusions. Endotoxin and the primary cytokines were positively correlated, both in the whole material and in the sterile effusions alone. The adhesion molecules were positively correlated with each other, but not with endotoxin or the primary cytokines. CONCLUSIONS: We found a positive correlation between endotoxin and the primary cytokines TNFalpha and IL1beta in culture-positive OME effusions as well as in culture-negative ones, suggesting endotoxin-induced local production of TNFalpha and IL1beta in the middle ear. ICAM-1 and VCAM-1 were also present in the middle ear, but their concentrations were not directly correlated to endotoxin or the primary cytokines.

Effect of N-acetylcysteine on the incidence of recurrence of otitis media with effusion and re-insertion of ventilation tubes.

Previous studies have demonstrated the anti-inflammatory, anti-oxidant, and mucolytic nature of N-acetylcysteine (NAC). Theoretically, these properties make the substance ideal for therapeutic use against otitis media with effusion (OME). The disease is characterized as a sustained non-specific inflammation of the middle ear mucosa with secretory transformation of the epithelium resulting in accumulation of fluid in the middle ear space. To investigate the effects of instillation of NAC in the middle ear, a double-blind, placebo-controlled, randomized trial was carried out. A total of 75 children who were undergoing their first bilateral insertion of ventilation tubes (VT) due to OME were randomized to Mucomyst (NAC) or placebo (the vehicle) on one ear in relation to the VT insertion. The contralateral ear underwent VT insertion exclusively. Instillation of Mucomyst or placebo was repeated 3 and 7 days afterwards. The children were followed regularly for 11-39 months. Episodes of otorrhea, recurrence of OME after VT extrusion and re-insertion of VTs were registered as primary outcome parameters. The results demonstrated that Mucomyst significantly reduced the recurrence of OME and re-insertion of VTs (p < 0.025) and significantly increased the time until VT extrusion (p < 0.0167). In addition, the number of episodes of ear problems and visits at the ENT clinic were reduced significantly by NAC (p < 0.0383).