Middle Ear Fluid Research Articles

Bacterial Species and Antibiotic Sensitivity in Korean Patients Diagnosed with Acute Otitis Media and Otitis Media with Effusion.

Changes over time in pathogens and their antibiotic sensitivity resulting from the recent overuse and misuse of antibiotics in otitis media (OM) have complicated treatment. This study evaluated changes over 5 years in principal pathogens and their antibiotic sensitivity in patients in Korea diagnosed with acute OM (AOM) and OM with effusion (OME). The study population consisted of 683 patients who visited the outpatient department of otorhinolaryngology in 7 tertiary hospitals in Korea between January 2010 and May 2015 and were diagnosed with acute AOM or OME. Aural discharge or middle ear fluid were collected from patients in the operating room or outpatient department and subjected to tests of bacterial identification and antibiotic sensitivity. The overall bacteria detection rate of AOM was 62.3% and OME was 40.9%. The most frequently isolated Gram-positive bacterial species was coagulase negative Staphylococcus aureus (CNS) followed by methicillin-susceptible S. aureus (MSSA), methicillin-resistant S. aureus (MRSA), and Streptococcus pneumonia (SP), whereas the most frequently isolated Gram-negative bacterium was Pseudomonas aeruginosa (PA). Regardless of OM subtype, ≥ 80% of CNS and MRSA strains were resistant to penicillin (PC) and tetracycline (TC); isolated MRSA strains showed low sensitivity to other antibiotics, with 100% resistant to PC, TC, cefoxitin (CFT), and erythromycin (EM); and isolated PA showed low sensitivity to quinolone antibiotics, including ciprofloxacin (CIP) and levofloxacin (LFX), and to aminoglycosides. Bacterial species and antibiotic sensitivity did not change significantly over 5 years. The rate of detection of MRSA was higher in OME than in previous studies. As bacterial predominance and antibiotic sensitivity could change over time, continuous and periodic surveillance is necessary in guiding appropriate antibacterial therapy.

Planktonic Growth of Pseudomonas aeruginosa around a Dual-Species Biofilm Supports the Growth of Fusobacterium nucleatum within That Biofilm.

Purpose The goal of this study was to understand the potential interaction between Pseudomonas aeruginosa and Fusobacterium nucleatum within the middle ear. MethodsWe examined the microbiota of ear fluid and tympanostomy tubes (TTs) obtained from patients with posttympanostomy tube otorrhea. We also examined biofilms formed by P. aeruginosa and F. nucleatum, singly or together, under aerobic or anaerobic conditions. Results While the facultative anaerobe P. aeruginosa dominated the bacterial population within the ear fluid, strict anaerobes, including F. nucleatum, dominated bacterial populations within the TTs. F. nucleatum was able to grow under aerobic conditions only in the presence of P. aeruginosa, whose growth reduced the level of dissolved oxygen within the broth to nearly anoxic condition within 4 h after inoculation. The presence of P. aeruginosa allowed F. nucleatum to maintain its growth for 72 h within the dual-species biofilm but not within the planktonic growth. Visualization of the biofilms revealed coaggregation of P. aeruginosa and F. nucleatum. Conclusion Extrapolation of these results suggests that, within the middle ear fluid, the growth of P. aeruginosa produces the anaerobic conditions required for the growth of F. nucleatum, both within effusion and within biofilms.

Prediction of Fluid Characteristics in Pediatric Otitis Media with Effusion from the Tympanometry

Objective: To correlate the characteristics of type B tympanogram with the type of middle ear fluid in children suffering from persistent OME. Methodology: A prospective study was conducted on children with persistent OME for more than 3 months who failed to respond to medical treatment with type B tympanogram in one or both ears and were candidate for myringotomy. The middle ear fluid was aspirated and the viscosity of the fluid was evaluated objectively by measuring the diameter of the diffusion circle on a filter paper in mm. Results: Thirty eight children (70 ears) were enrolled in this study. The shape of type B tympanogram was either flat (67.14%) or peaked (32.86 %).Three fluid types were noticed in OME namely serous, mucoid and glue. The shape was highly correlated with the type of secretions. Compliance and gradient of type B tympanogram were negatively correlated with the viscosity of the secretions. Conclusion: Tympanometry is a beneficial clinical tool in prediction, diagnosis and management of OME. Characteristics of type B tympanogram were correlated with the viscosity of middle ear fluid. Detailed analysis of type B tympanogram can assist the clinicians in determining the indication of comprehensive treatment.

Acute otitis media caused by Streptococcus pneumoniae serotype 19A ST320 clone: epidemiological and clinical characteristics.

Streptococcus pneumoniae serotype 19A ST320, a highly multiresistant and virulent clone, has emerged as a common pathogen causing acute otitis media (AOM) in children. Patients aged 0-18 years with AOM who presented at Mackay Memorial Hospital, Taipei, Taiwan were prospectively enrolled between December 1, 2009, and November 30, 2012. For each patient, a specimen of middle-ear fluid was obtained and cultured. S. pneumoniae isolates were tested by serotyping, antibiotic-resistance profiling, and multilocus sequence typing. Demographic characteristics and clinical history of patients with pneumococcal AOM were recorded. Pneumococcal AOM was observed in 108 (24.8%) of 436 episodes. One hundred and four isolates of S. pneumoniae were available for study. The most common serotypes were 19A (67 isolates, 64.4%), followed by 19F (16 isolates, 15.4%), and 3 (7 isolates, 6.7%). Among the 85 sequence-typed isolates, Serotype 19A ST320 (50, 58.8%) was the most frequent. Children with AOM caused by Serotype 19A ST320 were younger (33.9 ± 21.4 months vs. 46.7 ± 35.9 months, p = 0.04) and had a higher rate of spontaneous rupture of the tympanic membrane (64.0% vs. 40%, p = 0.05) than those caused by isolates of other sequence types. Serotype 19A ST320 caused 90% of AOM episodes in children aged ≤ 12 months and had had higher resistance rates to penicillin according to meningeal breakpoints (p = 0.011), amoxicillin (p < 0.001) and trimethoprim/sulfamethoxazol (p < 0.001). It is better to use pneumococcal conjugate vaccine effective against Serotype 19A in early infancy to prevent the first and subsequent episodes of AOM in children in Taiwan.

Trivalent pneumococcal protein vaccine protects against experimental acute otitis media caused by Streptococcus pneumoniae in an infant murine model

BackgroundCurrently licensed serotype-based pneumococcal vaccines are effective in preventing invasive pneumococcal diseases, but less effective in preventing non-bacteremic pneumonia and acute otitis media (AOM). We previously reported that a trivalent pneumococcal protein recombinant vaccine (PPrV) protected against pneumonia in a murine model. Here we evaluated PPrV protection against AOM in an infant murine model. MethodsC57BL/6J mice were intramuscularly vaccinated at 1–3weeks of age with monovalent pneumococcal histidine triad protein D (PhtD), or pneumococcal choline binding protein A (PcpA), or detoxified pneumolysin (PlyD1), or trivalent vaccine, and transtympanically challenged at 7–8weeks of age with 1×102CFU of pneumococcal strain BG7322 (6A) or 1×104CFU of pneumococcal nontypeable strain 0702064MEF. Serum IgG titers were determined by ELISA. At 24 and 48h post infection (hpi), animals were sacrificed and middle ear fluid (MEF) samples were collected to determine pneumococcal CFUs. ResultsWe found that vaccination of infant mice with monovalent and trivalent pneumococcal proteins elicited significant serum IgG antibody responses to corresponding component proteins. Vaccination with PhtD reduced BG7322 bacterial burdens in MEF at both 24 (p=0.05) and 48hpi (p=0.16). Vaccination with PcpA significantly reduced the bacterial burdens in MEF at both 24 (p=0.02) and 48hpi (p=0.004), and PlyD1 significantly reduced bacterial burden in MEF at 48hpi (p=0.02). Vaccination with trivalent PPrV (PhtD, PcpA and PlyD1) significantly reduced Spn burdens in MEF at both 24 (p=0.001) and 48hpi (p<0.0001). Similar reductions of bacterial burdens were found when the vaccinated animals were challenged with a non-typeable Spn strain. Vaccinated mice had significantly milder inflammatory cytokine levels (IL-1β, IL-6, TNF-α, MIP-2 and KC) in middle ears at 24hpi (all p values<0.05). ConclusionTrivalent PPrV confers protection against pneumococcal AOM in an infant murine model.

Differences in innate immune response gene regulation in the middle ear of children who are otitis prone and in those not otitis prone.

Acute otitis media (AOM) causes an inflammatory response in the middle ear. We assessed differences in innate immune responses involved in bacterial defense at onset of AOM in children who were stringently defined as otitis prone (sOP) and children not otitis prone (NOP). Innate immune genes analysis from middle ear fluid (MEF) samples of children. Genes of toll-like receptors (TLR), nod-like and retinoic acid-inducible gene-I-like receptors, downstream effectors important for inflammation and apoptosis, including cytokines and chemokines, were studied from MEF samples by using a real-time polymerase chain reaction array. Protein levels of differentially regulated genes were measured by Luminex. Gene expression in MEF among children who were sOP was significantly different in upregulation of interleukin 8, secretory leukocyte peptidase inhibitor, and chemokine (C-C motif) ligand 3, and in downregulation of interferon regulatory factor 7 and its related signaling molecules interferon alpha, Toll-like receptor adaptor molecule 2, chemokine (C-C motif) ligand 5, and mitogen-activated protein kinase 8 compared with children who were NOP. Differences in innate gene regulation were similar when AOM was caused by Streptococcus pneumoniae or nontypeable Haemophilus influenzae. Innate-immune response genes are differentially regulated in children who were sOP compared with children with NOP.

Using Pneumococcal Carriage Data to Monitor Postvaccination Changes in the Incidence of Pneumococcal Otitis Media.

Pneumococcal conjugate vaccines (PCVs) have substantially reduced the burden of pneumococcal disease, including the incidence of otitis media (OM). However, in most countries, no surveillance exists to monitor the change in pneumococcal OM incidence after the introduction of PCVs. We explored whether measuring pneumococcal carriage was a useful surrogate for monitoring postvaccination changes in the incidence of pneumococcal OM. The 7-valent PCV was introduced to Israel's national immunization program in July 2009 and gradually replaced by the 13-valent PCV starting in November 2010. Each day since 2009, nasopharyngeal swabs have been obtained from the first 4 Bedouin children and the first 4 Jewish children who were younger than 5 years old and attended a pediatric emergency room in southern Israel. During the same time, OM surveillance in southern Israel included all children younger than 2 years of age who were diagnosed with OM and had undergone a middle-ear fluid culture. The relative change in the prevalence of vaccine-serotype (VT) pneumococcal carriage was predictive of the relative change in incidence of OM due to VT pneumococcus. However, the serotype replacement observed in non-VT carriage is not paralleled in the incidence of OM due to non-VT pneumococcus. This could indicate that there are more complex mechanisms of the immune response involved in preventing initial and consecutive episodes of OM, which has been changed through declining prevalence of the most virulent serotypes as a result of vaccination.

Modeling Specific Antibody Responses to Natural Immunization to Predict a Correlate of Protection Against Infection Before Commencing a Clinical Vaccine Trial

ABSTRACTBackground: Clinical trials of vaccines for children to prevent acute otitis media (AOM) infections caused by the bacteria Streptococcus pneumonia (Spn) are in Phase I. The objective of this study was to use serum antibody measurements to pneumococcal purified protein candidate antigens that occurred after natural “immunization” to predict a correlate of protection response needed following an injectable vaccine against AOM in children.Methods: 590 nasal and serum samples were collected from 129 healthy children at 6, 9, 12, 15, 18, 24 and 30–36 months of age and when the child developed AOM. Middle ear fluid to detect Spn was collected at every episode of AOM. Quantitative ELISA was used to determine serum IgG against 7 Spn vaccine antigens: PspA clade 3, PspA clade 5, PhtD, PhtE, LytB, PcpA and Ply. A correlate of protection (COP) was estimated by regressing AOM events against age adjusted antibody levels induced by nasopharyngeal colonization and AOM infections, using logistic regression and ge...

Increased IL-17 and 22 mRNA expression in pediatric patients with otitis media with effusion

ObjectivesMiddle ear effusion has been reported to be associated with immune responses in patients with otitis media with effusion (OME). Although various cytokines are involved in immunologic responses in patients with OME, no study to date has assessed the involvement of the pro-inflammatory cytokines interleukin (IL)-17 and IL-22. This study analyzed the levels of expression of IL-17 and IL-22 in the middle ear effusion of patients with OME. MethodsPatients aged <11 years who were diagnosed with chronic OME and underwent ventilation tube insertion from May 2013 to August 2015 were enrolled. Effusion fluid samples were obtained during surgery and levels of IL-17 and IL-22 mRNAs assessed by real-time PCR. IL-17 and IL-22 mRNA levels were compared in patients with effusion fluid positive and negative for bacteria; in patients with and without accompanying diseases, recurrent disease, and re-operation; and relative to fluid characteristics. ResultsThe study cohort included 70 pediatric patients, 46 boys and 24 girls, of mean age 4.31 ± 2.11 years. The levels of IL-17 and IL-22 mRNA were higher in patients with than without sinusitis, but only IL-22 mRNA levels differed significantly (p < 0.05). The level of IL-17 mRNA was significantly higher in patients who did than did not undergo T&A (p < 0.05). The level of IL-22 expression was significantly higher in mucoid and purulent middle ear fluid samples than in serous fluid samples (p < 0.05). ConclusionIL-17 and IL-22 mRNAs are involved in the pathophysiology of OME and are significantly higher in subjects with than without accompanying diseases.

Younger patients with COME are more likely to have mucoid middle ear fluid containing mucin MUC5B

BackgroundChronic otitis media (COM) is one of the most common childhood diseases. Its pathophysiology is complex and multifactorial. The role of specific mucin glycoprotein subtypes in OM is only recently being elucidated. ObjectiveTo determine the relationship between middle ear fluid mucins and clinical variables of patients needing tympanostomy tubes (TT). MethodsMiddle ear effusions (MEE) from children receiving TT were collected over a 2-year period. Western blot characterization of mucins MUC5B and MUC5AC along with chart review of age, gender, effusion viscosity, hearing loss >30 dB, history of allergies, and/or respiratory disease were performed. ResultsMEE samples from 58 patients were available for analysis. Overall, MUC5B was significantly more often detected in middle ear fluid relative to MUC5AC (90% vs. 51%, p = 0.005). MUC5B presence was statistically associated with mucoid effusions relative to serous effusions (100% vs. 57%, p = 0.0064), MUC5AC presence was not significantly different in mucoid and serous fluid (55.1% vs. 37.5%, p = 0.447). Patients younger than 48 months were more likely to present with mucoid effusion, compared to those older than 48 months of age (p = 0.038). Finally, patients with effusions positive for MUC5B were younger than those with effusions negative for MUC5B (35.1 vs. 76 months, p = 0.045). No other variables correlated to either effusion viscosity or specific mucin content. ConclusionPatients younger in age needing TT placement are more likely to present with mucoid effusions, predominantly containing MUC5B mucin. As such, we postulate a distinct pathophysiology for mucoid and serous effusions across ages in children with COM.

Ten-Year Study of Acute Otitis Media in Rochester, NY.

This review summarizes a prospective, longitudinal 10-year study in Rochester, NY, involving 760 children where virtually all clinically diagnosed acute otitis media (AOM) was confirmed by bacterial culture of middle ear fluid. This review describes detection of otopathogens in middle ear fluid, nasopharyngeal (NP) otopathogen colonization patterns, AOM risk factor analysis, biomarkers of AOM and antibody responses to NP colonization by otopathogens. After licensure of PCV13, there was an immediate drop in AOM caused by Streptococcus pneumoniae (Spn) vaccine serotypes and shortly thereafer an increase in nonvaccine types 16, 21 and 35B. When NP co-colonization occurred, nontypeable Haemophilus influenzae (NTHi) predominated over Spn to cause AOM, and NTHi and Spn both predominated over Moraxella catarrhalis. Transcriptome analysis of peripheral blood mononuclear cells identified unique signatures for NTHi AOM compared with Spn AOM. Elevation of 3 cytokines in serum (S100A12, intercellular adhesion molecule 1 and interleukin 10) accurately predicted the presence and recovery from AOM and the likely otopathogen. NP colonization was an immunizing event.

Reflectance Measures from Infant Ears With Normal Hearing and Transient Conductive Hearing Loss.

The objective is to develop methods to utilize newborn reflectance measures for the identification of middle-ear transient conditions (e.g., middle-ear fluid) during the newborn period and ultimately during the first few months of life. Transient middle-ear conditions are a suspected source of failure to pass a newborn hearing screening. The ability to identify a conductive loss during the screening procedure could enable the referred ear to be either (1) cleared of a middle-ear condition and recommended for more extensive hearing assessment as soon as possible, or (2) suspected of a transient middle-ear condition, and if desired, be rescreened before more extensive hearing assessment. Reflectance measurements are reported from full-term, healthy, newborn babies in which one ear referred and one ear passed an initial auditory brainstem response newborn hearing screening and a subsequent distortion product otoacoustic emission screening on the same day. These same subjects returned for a detailed follow-up evaluation at age 1 month (range 14 to 35 days). In total, measurements were made on 30 subjects who had a unilateral refer near birth (during their first 2 days of life) and bilateral normal hearing at follow-up (about 1 month old). Three specific comparisons were made: (1) Association of ear's state with power reflectance near birth (referred versus passed ear), (2) Changes in power reflectance of normal ears between newborn and 1 month old (maturation effects), and (3) Association of ear's newborn state (referred versus passed) with ear's power reflectance at 1 month. In addition to these measurements, a set of preliminary data selection criteria were developed to ensure that analyzed data were not corrupted by acoustic leaks and other measurement problems. Within 2 days of birth, the power reflectance measured in newborn ears with transient middle-ear conditions (referred newborn hearing screening and passed hearing assessment at age 1 month) was significantly greater than power reflectance on newborn ears that passed the newborn hearing screening across all frequencies (500 to 6000 Hz). Changes in power reflectance in normal ears from newborn to 1 month appear in approximately the 2000 to 5000 Hz range but are not present at other frequencies. The power reflectance at age 1 month does not depend significantly on the ear's state near birth (refer or pass hearing screening) for frequencies above 700 Hz; there might be small differences at lower frequencies. Power reflectance measurements are significantly different for ears that pass newborn hearing screening and ears that refer with middle-ear transient conditions. At age 1 month, about 90% of ears that referred at birth passed an auditory brainstem response hearing evaluation; within these ears the power reflectance at 1 month did not differ between the ear that initially referred at birth and the ear that passed the hearing screening at birth for frequencies above 700 Hz. This study also proposes a preliminary set of criteria for determining when reflectance measures on young babies are corrupted by acoustic leaks, probes against the ear canal, or other measurement problems. Specifically proposed are "data selection criteria" that depend on the power reflectance, impedance magnitude, and impedance angle. Additional data collected in the future are needed to improve and test these proposed criteria.

Doppler optical coherence tomography as a promising tool for detecting fluid in the human middle ear

Abstract The treatment of otitis media requires classifying the effusion in the tympanic cavity for choosing appropriate therapeutic strategies. Otoscopic examination of the middle ear depends on the expertise of the physician and is often hampered in case of inflammatory alterations of the tympanic membrane. In otologic research, optical coherence tomography is an innovative non-invasive imaging technique utilized for visualizing the tympanic membrane. This ex vivo study presents the possibility of OCT and Doppler-OCT for the detection of effusions in the tympanic cavity. Structural OCT imaging allows the direct visualization of scattering fluids behind the tympanic membrane. In addition, the measurement of the reduced oscillation amplitude by means of Doppler-OCT permits the indirect detection of scattering and transparent fluids.

Ten-Year Study of the Stringently Defined Otitis-prone Child in Rochester, NY.

This review summarizes a prospective, longitudinal 10-year study in Rochester, NY, with virtually every clinically diagnosed acute otitis media (AOM) confirmed by bacterial culture of middle ear fluid. Children experiencing 3 episodes within 6 months or 4 episodes in 12 months were considered stringently defined otitis prone (sOP). We found stringent diagnosis compared with clinical diagnosis reduced the frequency of children meeting the OP definition from 27% to 6% resulting in 14.8% and 2.4% receiving tympanostomy tubes, respectively. Significantly more often respiratory syncytial virus infection led to AOM in sOP than non-otitis-prone children that correlated with diminished total respiratory syncytial virus-specific serum IgG. sOP children produced low levels of antibody to Streptococcus pneumoniae and Haemophilus influenzae candidate vaccine protein antigens and to routine pediatric vaccines. sOP children generated significantly fewer memory B cells, functional and memory T cells to otopathogens following nasopharyngeal colonization and AOM than non-otitis-prone children and they had defects in antigen-presenting cells.

Reduction of Streptococcus pneumoniae in upper respiratory tract cultures and a decreased incidence of related acute otitis media following introduction of childhood pneumococcal conjugate vaccines in a Swedish county

BackgroundThe effect of pneumococcal conjugate vaccines (PCV) on invasive pneumococcal disease is frequently reported, but the impact on upper respiratory tract infections in a clinical setting is less documented. Our aim in this 5-year observational study was to investigate serotype changes in a large number of Streptococcus pneumoniae upper respiratory tract isolates following sequential introduction of PCV7 and pneumococcal Haemophilus influenza protein D conjugate vaccine (PHiD-CV10) in a Swedish county.MethodsAll bacterial isolates from the upper respiratory tract (nasopharynx, sinus or middle ear fluid) from patients with respiratory tract infections referred to a clinical microbiology laboratory prior to (2 years 2007–2008; n = 1566) and after introduction of PCV (3 years 2011–2013; n = 1707) were prospectively collected. Microbiological findings were compared between the two periods, and information from clinical referrals was recorded in order to explore changes in incidence of pneumococcal acute otitis media (AOM).ResultsPneumococcal serotypes covered by PHiD-CV10 decreased from 45 to 12 % prior to and after immunization (p < 0.001), respectively. Despite non-PHiD-CV10 serotypes increased from 49 to 80 %, a significant decline of 35 % in the absolute incidence of pneumocococal isolates (p < 0.001) was observed. Finally, the frequency of complicated AOM caused by S. pneumoniae decreased by 32 % (p < 0.001).ConclusionsAfter introduction of PCV in 2009, we have observed a significantly decreased number of pneumococcal isolates in the upper respiratory tract, a shift to non-PHiD-CV10 serotypes, and a reduction of complicated AOM. Our findings may have implications for future vaccine design.

Contemporary Guidelines for Tympanostomy Tube Placement

Tympanostomy tubes remain the most commonly performed operation globally. They facilitate drainage of middle ear fluid, direct delivery of ototopical antibiotics as well as other therapies, and reduce the risk of complications related to severe Eustachian tube dysfunction. They remain an invaluable tool especially in children at risk of speech and language delay. In this chapter, we will review the current indications for tube placement, risks, benefits, and controversies related to their use as well as innovations in the types of tympanostomy tubes currently in use.

Moraxella catarrhalis Might Be More Common than Expected in Acute Otitis Media in Young Finnish Children.

According to studies based on bacterial cultures of middle ear fluids, Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis have been the most common pathogens in acute otitis media. However, bacterial culture can be affected by reduced viability or suboptimal growth of bacteria. PCR detects bacterial DNA from samples with greater sensitivity than culture. In the present study, we analyzed the middle ear pathogens with both conventional culture and semiquantitative real-time PCR in 90 middle ear fluid samples obtained from children aged 5 to 42 months during acute otitis media episodes. Samples were tested for the presence of S. pneumoniae, H. influenzae, M. catarrhalis, Alloiococcus otitidis, Staphylococcus aureus, and Pseudomonas aeruginosa One or more bacterial pathogens were detected in 42 (47%) samples with culture and in 69 (77%) samples with PCR. According to PCR analysis, M. catarrhalis results were positive in 42 (47%) samples, H. influenzae in 30 (33%), S. pneumoniae in 27 (30%), A. otitidis in 6 (6.7%), S. aureus in 5 (5.6%), and P. aeruginosa in 1 (1.1%). Multibacterial etiology was seen in 34 (38%) samples, and M. catarrhalis was detected in most (85%) of those cases. Fifteen signals for M. catarrhalis were strong, suggesting a highly probable etiological role of the pathogen. In conclusion, even though M. catarrhalis is often a part of mixed flora in acute otitis media, a considerable proportion of cases may be primarily attributable to this pathogen.

Efficacy of Solithromycin (CEM-101) for Experimental Otitis Media Caused by Nontypeable Haemophilus influenzae and Streptococcus pneumoniae.

Solithromycin (CEM-101) is a "fourth-generation" macrolide, as it has three binding site and is acid stable. The three binding sites confer activity against bacteria resistant to the older macrolides and ketolides, including multidrug-resistant Streptococcus pneumoniae and nontypeable Haemophilus influenzae (NTHi). The objective of this study was to evaluate solithromycin pharmacokinetics (PK), middle ear fluid (MEF) concentrations, and microbiologic efficacy in a chinchilla model of experimental otitis media (EOM) due to strains of S. pneumoniae or NTHi. Plasma PK (maximum concentration of drug in serum [Cmax] and area under the concentration-time curve from 0 to 24 h [AUC0-24]) and middle ear fluid (MEF) concentrations were determined. Isolates with specified antimicrobial susceptibility patterns were inoculated directly into the middle ear (ME). Plasma and MEF were collected for PK and MEF cultures performed to determine efficacy. Solithromycin administered at 150 mg/kg of body weight/day resulted in Cmax and AUC0-24 values of 2.2 μg/ml and 27.4 μg · h/ml in plasma and 1.7 μg/ml and 28.2 μg · h/ml in extracellular MEF on day 1. By day 3, Cmax and AUC0-24 values had increased to 4.5 μg/ml and 54 μg · h/ml in plasma and 4.8 μg/ml and 98.6 μg · h/ml in extracellular MEF. For NTHi EOM, three isolates with MIC/minimal bactericidal concentration (MBC) ratios of 0.5/1 μg/ml (isolate BCH1), 2/2 μg/ml (isolate BMC1247C), and 4/4 μg/ml (isolate BMC1213C) were selected. The MEF of >85% of animals infected with BCH1 and BMC1247C was sterilized. For NTHi BMC1213, >85% of MEF cultures remained positive. For S. pneumoniae EOM, 3 isolates with MIC/MBC ratios of 0.06/0.125 μg/ml (S. pneumoniae 331), 0.125/1 μg/ml (S. pneumoniae CP-645 [MLSB phenotype]), and 0.5/2 μg/ml (CP-712 [mefA subclass mefA resistance]) were selected. Solithromycin sterilized MEF in 100% of animals infected with S. pneumoniae 331 and S. pneumoniae CP-645. ME infection persisted in 60% of animals infected with CP-712. In a model of EOM, solithromycin sterilized MEF in >85% of animals challenged with NTHi with an MIC of ≤2 μg/ml and 100% of ME infected with S. pneumoniae with an MIC of ≤0.125 μg/ml.

Pneumococcal vaccine impact on otitis media microbiology: A New Zealand cohort study before and after the introduction of PHiD-CV10 vaccine

We compared the microbiology of middle ear fluid (MEF) in two cohorts of children having ventilation tube (VT) insertion; the first in the era of 7-valent Streptococcus pneumoniae conjugate vaccine (PCV7) and the second following introduction of the ten-valent pneumococcal vaccine (PHiD-CV10). MethodsDuring 2011 (Phase 1) and again in 2014 (Phase 2) MEF and NP samples from 325 children and 319 children were taken at the time of VT insertion. A matched comparison group had NP swabs collected with 137 children (Phase 1) and 154 (Phase 2). Culture was performed on all NP and MEF samples with further molecular identification of Haemophilus species, serotyping of S. pneumoniae, and polymerase chain reaction (PCR) testing on all MEF samples. ResultsIn Phase 2 immunisation coverage with ⩾3 doses of PHiD-CV10 was 93%. The rate and ratios of culture and molecular detection of the 3 main otopathogens was unchanged between Phase 1 and Phase 2 in both MEF and NP. Haemophilus influenzae was cultured in one quarter and detected by PCR in 53% of MEF samples in both time periods. S. pneumoniae and Moraxella catarrhalis were cultured in up to 13% and detected by PCR in 27% and 40% respectively of MEF samples. H. influenzae was the most common organism isolated from NP samples (61%) in the children undergoing VT surgery whilst M. catarrhalis (49%) was the most common in the non-otitis prone group. 19A was the most prominent S. pneumoniae serotype in both MEF and NP samples in Phase 2. Of Haemophilus isolates, 95% were confirmed to be non-typeable H. influenzae (NTHi) over both time periods. ConclusionFollowing implementation of PHiD-CV10 in New Zealand, there has been no significant change in the 3 major otopathogens in NP or MEF in children with established ear disease. For these children non-typeable H. influenzae remains the dominant otopathogen detected.

What is the role of preoperative imaging for cochlear implants in adults with postlingual deafness?

What is the role of preoperative imaging for cochlear implants in adults with postlingual deafness?