Otitis media susceptibility and shifts in the head and neck microbiome due to SPINK5 variants.

BACKGROUND: Otitis media (OM) susceptibility has significant heritability; however, the role of rare variants in OM is mostly unknown. Our goal is to identify novel rare variants that confer OM susceptibility. METHODS: We performed exome and Sanger sequencing of >1000 DNA samples from 551 multiethnic families with OM and unrelated individuals, RNA-sequencing and microbiome sequencing and analyses of swabs from the outer ear, middle ear, nasopharynx and oral cavity. We also examined protein localisation and gene expression in infected and healthy middle ear tissues. RESULTS: A large, intermarried pedigree that includes 81 OM-affected and 53 unaffected individuals cosegregates two known rare A2ML1 variants, a common FUT2 variant and a rare, novel pathogenic variant c.1682A>G (p.Glu561Gly) within SPINK5 (LOD=4.09). Carriage of the SPINK5 missense variant resulted in increased relative abundance of Microbacteriaceae in the middle ear, along with occurrence of Microbacteriaceae in the outer ear and oral cavity but not the nasopharynx. Eight additional novel SPINK5 variants were identified in 12 families and individuals with OM. A role for SPINK5 in OM susceptibility is further supported by lower RNA counts in variant carriers, strong SPINK5 localisation in outer ear skin, faint localisation to middle ear mucosa and eardrum and increased SPINK5 expression in human cholesteatoma. CONCLUSION: SPINK5 variants confer susceptibility to non-syndromic OM. These variants potentially contribute to middle ear pathology through breakdown of mucosal and epithelial barriers, immunodeficiency such as poor vaccination response, alteration of head and neck microbiota and facilitation of entry of opportunistic pathogens into the middle ear.

Panel 1: Epidemiology, natural history, and risk factors.

BACKGROUND: The First International Symposium on Recent Advances in Otitis Media (OM) with Effusion was held in Columbus, Ohio, in 1975. The symposium has been organized in the United States every 4 years since, followed by a research conference to (a) assess major research accomplishments, (b) identify important research questions and opportunities, (c) develop consensus on definitions and terminology, and (d) establish priorities with short- and long-term research goals. One of the principal areas reviewed quadrennially is Epidemiology, Natural History, and Risk Factors. OBJECTIVE: To provide a review of recent literature on the epidemiology, natural history, and risk factors for OM. DATA SOURCES AND REVIEW METHODS: A search of OM articles in English published July 2007 to June 2011 was conducted using PubMed and related databases. Those with findings judged of importance for epidemiology, public health, and/or statistical methods were reviewed. RESULTS: The literature has continued to expand, increasing understanding of the worldwide burden of OM in childhood, complications from treatment failures, and comorbidities. Novel risk factors, including genetic factors, have been examined for OM susceptibility. Population-based studies in Canada, the United States, and other countries confirmed reductions in OM prevalence. Although most studies concentrated on acute OM (AOM) or OM with effusion (OME), a few examined severe chronic suppurative OM (CSOM), a major public health problem in developing countries and for certain indigenous populations around the world. CONCLUSIONS AND IMPLICATIONS FOR PRACTICE: Recent publications have reinforced earlier epidemiological findings, while extending our knowledge in human population groups with high burden of OM.

Evaluation of newborn screening bloodspot-based genetic testing as second tier screen for bedside newborn hearing screening.

PURPOSE: : Bedside newborn hearing screening is highly successful in identifying deaf or hard-of-hearing infants. However, newborn hearing screening protocols have high loss to follow-up rates. We propose that bloodspot-based genetic testing for GJB2 alleles can provide a means for rapid confirmation in a subset of infants who fail bedside newborn hearing screening. METHODS: : We performed a case-control study comparing the prevalence of common GJB2 mutations from deidentified bloodspots designated as "refer" by newborn hearing screening and contemporaneously selected randomly chosen controls designated as "pass." Between March 2006 and December 2007, 2354 spots were analyzed for common alleles, c.35delG, c.167delT, c.235delC, and p.V37I in GJB2 with a subset reanalyzed by conventional Sanger sequencing to search for additional alleles. RESULTS: : The prevalence of biallelic GJB2 mutations in bloodspots from infants who referred by newborn hearing screening is approximately 1 in 50 (23/1177). In contrast, one bloodspot from an infant who passed newborn hearing screening was identified to harbor biallelic GJB2 mutations. CONCLUSIONS: : These findings show that when a newborn refers by newborn hearing screening, there is a significant chance that GJB2-related hearing loss is present. Bloodspot-based genetic testing for common GJB2 alleles should be considered as second tier testing for bedside newborn hearing screening.

Epidemiology, natural history, and risk factors: panel report from the Ninth International Research Conference on Otitis Media.

The 2007 Recent Advances in Otitis Media Research Conference Panel Report provides an update on otitis media (OM) research published from 2003 to 2007. This report summarizes important trends in disease incidence and prevalence, describes established and newly identified risk factors for acute and chronic OM and OM with effusion, and conveys information on newly discovered genetic factors. In this report, researchers have described declining rates of OM diagnosis, antibiotic prescriptions, offices visits for OM, and middle ear surgery since the licensure and routine use of pneumococcal conjugate vaccine in infants. The panel report also recommends short and long term goals for current and future OM research.

American Indian breastfeeding attitudes and practices in Minnesota.

OBJECTIVES: We examined the breastfeeding attitudes and practices in an American Indian population in Minnesota. METHODS: We interviewed women prenatally (n = 380), at 2-weeks (n = 342) and at 6-months postpartum (n = 256). We conducted multivariable analyses to examine the demographic, behavioral, and attitudinal correlates of breastfeeding initiation and duration. RESULTS: Factors positively associated with breastfeeding initiation included positive breastfeeding attitudes and social support for breastfeeding from the woman's husband/boyfriend and her mother. Factors positively associated with breastfeeding at 2-weeks postpartum were support from the woman's mother and positive attitudes about breastfeeding. The prenatal use of traditional American Indian medicines and cigarette smoking were both significantly associated with breastfeeding at 6-months postpartum. CONCLUSIONS: Programs to encourage breastfeeding in American Indian communities may be strengthened with protocols to encourage social support, recognition of the perceived health, developmental, and practical benefits of breastfeeding, and a focus on traditional American Indian health practices.

Presence of otitis media with effusion and its risk factors affect serum cytokine profile in children.

UNLABELLED: Otitis media with effusion (OME) is a condition that has significant impact on the quality of life of children. Although the etiology is multi-factorial, certain risk factors such as an allergic predisposition, daycare, and cigarette smoke exposure contribute to its pathogenesis. OBJECTIVE: (1) To determine whether there is a tendency for children with chronic or recurrent OME (cases) to have higher serum levels of the T-helper 2 cell (Th-2) allergenic-type cytokines, interleukin-4 (IL-4), and IL-5, or the T-helper 1(Th-1) infectious-type cytokines, interferon-gamma (IFN-gamma), and tumor necrosis factor-alpha (TNF-alpha), compared to children without a history of recurrent OME (controls) and (2) to determine any possible correlations between the cytokine levels and risk factors associated with OME. METHODS: We analyzed serum levels of these four cytokines by enzyme-linked immunosorbent assays of 19 cases and 17 controls. RESULTS: Cases, independent of age, had increased levels of serum IL-5 compared to controls (p=0.014). While a significant difference in serum IL-4 levels did not exist between cases and controls, children exposed to cigarette smoke had significantly higher levels of serum IL-4 (p=0.003). While serum levels of IFN-gamma were statistically significantly higher in cases than controls with univariate analysis (p=0.011), when controlling for age and smoke exposure with multivariate analyses, the difference did not reach significance (p=0.086). CONCLUSION: These results suggest that patients with chronic or recurrent OME and those exposed to cigarette smoke mount a Th-2 allergic-like response, as demonstrated by their serum cytokines.

Hearing screening and middle ear measures in American Indian infants and toddlers.

UNLABELLED: American Indian children have three times the rate of otitis media compared to the general population, yet prospective cohort studies of OME and hearing loss have not been previously reported in American Indian infants. Between 1997 and 2003, a cohort of 421 infants was enrolled at birth from Minnesota American Indian reservations and an urban clinic and followed to age 2 years. This study reports OAE hearing screening results related to OME diagnoses, as well as risk for recurrent hearing screening failure and OME in American Indian infants and children. METHODS: Infants were prospectively assessed at regular intervals with pneumatic otoscopy, distortion product otoacoustic emissions, and tympanometry by nurses who were trained in all procedures and validated on pneumatic otoscopy. RESULTS: In the newborn period, 23.5% of infants failed hearing screening in at least one ear. Hearing screening failures increased to 29.9% from 2 to 5 months of age. Technical fail results due to excessive noise occurred frequently in infants 6-24 months of age, making interpretation of true pass and fail rates questionable in older infants. OAE test result was associated with OM diagnosis, and this relationship strengthened with age, with the strongest association above 6 months of age. CONCLUSIONS: A high rate of hearing screening failures occurred among American Indian infants in the first 5 months of age, and was significantly associated with a correspondingly high rate of otitis media. Only one infant out of 366 was identified with sensorineural hearing loss, thus essentially all of the hearing screening failures reflected either a middle ear origin or other temporary problems. OAE screening provided a valuable hearing screening measure in this population at high risk for recurrent otitis media, but due to excessive noise in infants 6 months and older, practical use of OAE screening is limited. Use of behavioral assessment is needed after 6 months of age, when high rates of OME persist in this population. Increased efforts to develop public and medical education, as well as screening, diagnosis and treatment programs are needed to detect and decrease recurrent OME in American Indian infants and children.

Early otitis media among Minnesota American Indians: the Little Ears Study.

OBJECTIVES: We examined relationships between otitis media risk factors, sociodemographic characteristics, and maternal knowledge and attitudes and early onset of otitis media. METHODS: Pregnant women from Minnesota American Indian reservations and an urban clinic were enrolled in our study between 1998 and 2001. Follow-up was performed on enrollees' infants until the children were 2 years old. Research nurses collected data by ear examination, from interviews and questionnaires given to enrolled mothers, and otitis media episodes that were abstracted from medical records. RESULTS: Sixty-three percent of infants had experienced an otitis media episode by 6 months of age. Logistic regression analyses showed that maternal otitis media history, infant history of upper respiratory infection, and compliance with study visits were significantly related to early otitis media onset. Although high percentages of infants were exposed to cigarette smoke and other children and were formula fed, these factors were not related to otitis media. Mothers' prenatal awareness of otitis media risks associated with environmental tobacco smoke exposure and formula feeding did not predict their postpartum behaviors. CONCLUSIONS: We found that infant history of upper respiratory infection and maternal otitis media history are risk factors for early otitis media in American Indian infants. Mothers' prepartum knowledge and attitudes regarding otitis media did not predict their postpartum avoidance of risk behaviors.

Association of the FBXO11 gene with chronic otitis media with effusion and recurrent otitis media: the Minnesota COME/ROM Family Study.

OBJECTIVE: The FBXO11 gene is the human homologue of the gene mutated in the novel deaf mouse mutant jeff (Jf), a single gene model of otitis media. We have evaluated single nucleotide polymorphisms (SNPs) in the FBXO11 gene for association with chronic otitis media with effusion/recurrent otitis media (COME/ROM). DESIGN: A total of 13 SNPs were genotyped across the 98.7 kilobases of genomic DNA encompassing FBXO11. Data were analyzed for single SNP association using generalized estimating equations, and haplotypes were evaluated using Pedigree Disequilibrium Test methods. PATIENTS: The Minnesota COME/ROM Family Study, a group of 142 families (619 subjects) with multiple affected individuals with COME/ROM. MAIN OUTCOME MEASURES: Genetic association of COME/ROM with polymorphisms in FBXO11. RESULTS: The FBXO11 SNPs are contained in a single linkage disequilibrium haplotype block. Ten of the 13 SNPs were sufficiently polymorphic in the sample to permit analysis. In univariate genetic analysis, 1 reference SNP (hereinafter rs) (rs2134056) showed nominal evidence of association to COME/ROM (P = .02), and 2 SNPs approached significance (rs2020911, P = .06; rs3136367, P = .09). In multivariable analyses, including known risk factors for COME/ROM (sex, exposure to smoking, attending day care centers, no prior breastfeeding, and having allergies), the evidence of independent association was reduced for each SNP (eg, rs2134056, from P = .02 to P = .08). In subsequent analyses using the Pedigree Disequilibrium Test, the association of FBXO11 SNP rs2134056 (P = .06) with COME/ROM was confirmed. Incorporating multiple SNPs in 2- and 3-locus SNP haplotypes, those haplotypes containing rs2134056 also exhibited evidence of association of FBXO11 and COME/ROM (P values ranging from .03 to .10). CONCLUSION: We have observed evidence consistent with an association between polymorphisms in FBXO11, the human homologue of the Jeff mouse model gene, and COME/ROM.

Chronic and recurrent otitis media: a genome scan for susceptibility loci.

Otitis media (OM) is the most common childhood disease. Almost all children experience at least one episode, but morbidity is greatest in children who experience chronic/recurrent OM (COME/ROM). There is mounting evidence that COME/ROM clusters in families and exhibits substantial heritability. Subjects who had tympanostomy tube surgery for COME/ROM (probands) and their families were recruited for the present study, and an ear examination was performed, without knowledge of the subject's history, to determine presence of OM sequelae. In addition, tympanometric testing was performed at three frequencies (226, 630 or 710, and 1,400 Hz) to detect abnormal middle-ear mechanics, and hearing was screened at 20 dB for the speech frequencies. Of these families, 121 had at least two individuals who had received the diagnosis of COME/ROM (364 affected and genotyped individuals), of whom 238 affected and informative relative pairs were used for analyses. Single-point nonparametric linkage analysis provided evidence of linkage of COME/ROM to chromosome 10q at marker D10S212 (LOD 3.78; P=3.0 x 10(-5)) and to chromosome 19q at marker D19S254 (LOD 2.61; P=5.3 x 10(-4)). Analyses conditional on support for linkage at chromosomes 10q and 19q resulted in a significant increase in LOD score support on chromosome 3p (between markers D3S4545 and D3S1259). These results suggest that risk of COME/ROM is determined by interactions between genes that reside in several candidate regions of the genome and are probably modulated by other environmental risk factors.

Chronic otitis media with effusion sequelae in children treated with tubes.

OBJECTIVE: To determine incidence and prevalence of middle ear sequelae and abnormal tympanometry results among children with chronic otitis media with effusion (OME) who received standard treatment with tympanostomy tubes. DESIGN: Prospective cohort study. SETTING: Community clinic and academic medical center. Patients A total of 140 children followed up for 8 years after tube treatment. MAIN OUTCOME MEASURES: Tympanic membrane perforation, atrophy, retraction, hearing loss, myringosclerosis, low static admittance (SA) and broad-peaked tympanogram, high SA and narrow-peaked tympanogram, and negative tympanometric peak pressure. RESULTS: Annual incidence of sequelae was typically greater during 3 to 5 years than 6 to 8 years of follow-up. Greatest increases in incidence during the 5-year follow-up were for atrophy (67%), high SA and narrow-peaked tympanogram (70%), and retraction pocket (47%). Prevalence of these sequelae also increased over time, whereas low SA and broad-peaked tympanogram and negative tympanometric peak pressure decreased during follow-up. Sequela tended to become bilateral over time, and concordance of different sequelae in the same ear was low (kappa, 0.05-0.42). CONCLUSIONS: Annual incidence of sequelae decreased during follow-up. This finding parallels decreasing incidence of OME and tube placement as children mature and demonstrates that sequelae are more likely to develop during active acute and chronic OME. The cumulative effect of incidence resulted in few ears free of sequelae by 8 years of follow-up. Based on this cohort of healthy children with OME, although the risk of sequelae decreased over time, functional and morphologic sequelae were prevalent and may put children at risk for continuing middle ear problems as they grow into adolescence and adulthood.

Cellular telephone use and risk of intratemporal facial nerve tumor.

OBJECTIVES/HYPOTHESIS: Microwave radiation exposure from cellular telephone use has been implicated in the development of intracranial tumors. The intratemporal facial nerve (IFN) is exposed to higher levels of cellular telephone radiation than intracranial tissues. The purpose of the study was to determine whether cellular telephone use is associated with an increased risk of IFN tumors. STUDY DESIGN: Case-control using a structured telephone survey at an academic, tertiary-care referral center. METHODS: Patients with IFN tumors (n = 18) were case-matched with patients treated for acoustic neuroma (n = 51), rhinosinusitis (n = 72), and dysphonia or gastroesophageal reflux disease (n = 69). Risk of facial nerve tumorigenesis was compared by extent of cellular telephone use and other risk factors. RESULTS: The odds ratio of developing an IFN tumor was 0.6 (95% CI, 0.2-1.9) with any handheld cellular telephone use and 0.4 (95% CI, 0.1-2.1) with regular cellular telephone use. No factors were associated with an increased risk for IFN tumor development. CONCLUSIONS: Regular cellular telephone use does not appear to be associated with a higher risk of IFN tumor development. The short duration of widespread cellular telephone use precludes definite exclusion as a risk for IFN tumor development.