Karen B. Teufert

Antimicrobial activity of innate immune molecules against Streptococcus pneumoniae, Moraxella catarrhalis and nontypeable Haemophilus influenzae

BackgroundDespite its direct connection to the nasopharynx which harbors otitis media pathogens as part of its normal flora, the middle ear cavity is kept free of these bacteria by as yet unknown mechanisms. Respiratory mucosal epithelia, including those of the middle ear and eustachian tube, secrete antimicrobial effectors including lysozyme, lactoferrin and β defensins-1 and -2. To elucidate the role of these innate immune molecules in the normal defense and maintenance of sterility of respiratory mucosa such as that of the middle ear, we assessed their effect on the respiratory pathogens nontypeable Haemophilus influenzae (NTHi) 12, Moraxella catarrhalis 035E, and Streptococcus pneumoniae 3, and 6B.MethodsTwo assay methods, the radial assay and the liquid broth assay, were employed for testing the antimicrobial activity of the molecules. This was done in order to minimize the possibility that the observed effects were artifacts of any single assay system employed. Also, transmission electron microscopy (TEM) was employed to evaluate the effect of antimicrobial innate immune molecules on OM pathogens. For the statistical analysis of the data, Students t-test was performed.ResultsResults of the radial diffusion assay showed that β defensin-2 was active against all four OM pathogens tested, while treatment with β defensin-1 appeared to only affect M. catarrhalis. The radial assay results also showed that lysozyme was quite effective against S. pneumoniae 3 and 6B and was partially bacteriostatic/bactericidal against M. catarrhalis. Lysozyme however, appeared not to affect the growth of NTHi. Thus, lysozyme seems to have a more pronounced impact on the growth of the Gram-positive S. pneumoniae as compared to that of Gram-negative pathogens. Lactoferrin on the other hand, enhanced the growth of the bacteria tested. The results of the radial assays were confirmed using liquid broth assays for antimicrobial activity, and showed that lysozyme and β defensin-2 could act synergistically against S. pneumoniae 6B. Moreover, in the liquid broth assay, β defensin-1 showed a modest inhibitory effect on the growth of S. pneumoniae 6B. As assessed by ultrastructural analysis, lysozyme and β defensin-2, and to a much lesser extent, β defensin-1, appeared to be able to cause damage to the bacterial membranes.ConclusionsHere we report that lysozyme and the β defensins can inhibit the growth of clinical isolates of otitis media pathogens – namely NTHi strain 12, S. pneumoniae strains 3 and 6B and M. catarrhalis strain 035E – and cause ultrastructural damage to these pathogens. Moreover, we demonstrate that lysozyme and β defensin-2 can act synergistically against S. pneumoniae. These findings are consistent with the concept that secreted antimicrobial peptides and other components of innate immunity constitute the first line of defense protecting host mucosal surfaces, including the tubotympanal (eustachian tube and middle ear cavity) mucosa, against pathogens.

Congenital aural atresia surgery: long-term results.

OBJECTIVES The study goal was to evaluate the stability of hearing results from short- to long-term follow-up in patients who underwent surgery for congenital aural atresia. We also reviewed complications such as external auditory canal stenosis, lateralization and perforation of the tympanic membrane, sensorineural hearing loss, and facial palsy. METHODS We conducted a retrospective chart review of 116 patients who underwent congenital aural atresiaplasty between 1985 and 2002 at the House Ear Clinic. There were 116 atretic ears. Complication rates and short- and long-term (up to 13.6 years) hearing results were evaluated for primary and revision cases. RESULTS Closure of the air-bone gap (ABG) to 30 dB or less at short-term follow-up occurred in 58.5% of primary surgeries and 56% of revisions. The long-term postoperative ABG was 30 dB or less in 50.8% of the primary cases and 39.1% of the revisions. Paired comparison analysis found no significant change in ABG from short- to long-term follow-up for either primary or revision cases. Soft tissue stenosis was seen in 8% of primary surgeries and 3.4% of revisions. Ossicular chain refixation was seen in 11.5% and 6.9% of primary and revision surgeries, respectively. There were no dead ears. CONCLUSION Atresiaplasty surgery in individuals with congenital aural atresia can yield reliable, lasting hearing results with a low incidence of complications.

Advances in Congenital Aural Atresia Surgery: Effects on Outcome

OBJECTIVES: To compare modifications in the surgical technique of congenital aural atresia (use of argon laser, thinner split-thickness skin graft, Silastic sheets in the external auditory canal, and Merocel wicks) by examining hearing results and complications before and after initiation of these changes. STUDY DESIGN AND SETTING: Retrospective chart review of patients who underwent congenital aural atresiaplasty between 1985 and 2002 in a tertiary referral neurotologic private practice. Complication rates and hearing results were compared before (n = 36) and after (n = 80) modifications in the surgical technique. RESULTS: Closure of the air-bone gap to 30 dB or less at short-term follow-up occurred in 63.1% of surgeries performed after modifications in the surgical technique and 44.5% of surgeries performed before these changes. The long-term postoperative air-bone gap was 30 dB or less in 50.0% of the surgeries performed after and 47.1% of the cases performed before the changes in surgical technique. Soft tissue stenosis and bony growth of the external auditory canal were seen in 3.8% of surgeries performed after and 13.9% of surgeries performed before the surgical technique changes. Ossicular chain refixation occurred in 3.8% of surgeries performed after and 25.0% of surgeries performed before such changes. There were no dead ears and no facial palsies. CONCLUSION: The use of argon laser, thinner split-thickness skin graft, Silastic sheets in the external auditory canal, and Merocel wicks, as a group, has helped to improve hearing results and decrease the incidence of complications in congenital aural atresia surgery. SIGNIFICANCE: Refinements in surgical techniques can lead to measurable improvements in outcome in atresiaplasty.

Extrusion rates and hearing results in ossicular reconstruction.

OBJECTIVES: To examine hearing results, extrusion rates, and factors likely to affect outcome in patients who underwent ossicular chain reconstruction with Plasti-Pore and hydroxylapatite total ossicular replacement prostheses (TORPs) and partial ossicular replacement prosthesis (PORPs). STUDY DESIGN AND SETTING: Retrospective chart review was used. Subjects were 1210 consecutive tympanoplasties with or without mastoidectomy that involved ossicular reconstruction with TORPs (n = 560) or PORPs (n = 650) performed in a tertiary referral neurotologic private practice. Only 20% of the cases were primary surgeries, with the majority planned second stage or revision procedures. RESULTS: Average last postoperative air-bone gap (ABG) was 19.2 dB with closure of the ABG to within 20 dB in 62.9%. Hearing results were better for cases who had not had previous surgery, in those with a diagnosis other than chronic otitis media, when a cartilage graft was used, and for Plasti-Pore rather than hydroxylapatite. Extrusion was known to occur in 4%. CONCLUSION: After more than 25 years of use in our clinic, Plasti-Pore ossicular replacement pros-theses continue to provide reliable hearing results with a low rate of extrusion.

Transcochlear approach to cerebellopontine angle and clivus lesions: indications, results, and complications.

Objectives: Evaluate transcochlear (TC)/transotic (TO) approaches surgery for midline intradural lesions arising from the clivus and cerebellopontine angle masses arising anterior to the internal auditory canal. Study Design: Retrospective chart review. Setting: Tertiary referral neurotologic practice. Patients/Intervention: Forty patients who underwent TC/TO approach surgery. Patients were grouped by whether the facial nerve was mobilized (TC, n = 15) or not (TO, n = 25). Main Outcome Measures: Indications, postoperative outcomes, and complications including tumor removal and facial nerve status (House-Brackmann grade). Results: Forty percent of all TC patients were meningiomas, whereas 36% of all TO patients were cochlear neuromas. The remainder included tumors associated with NF2, acoustic tumors, malignancies, and other lesions. Complete removal was achieved in 92.5% of tumors. Of all patients, 42% and 55% had normal facial nerve function at the time of hospital discharge and follow up, respectively. Moreover, 22% underwent a facial nerve reanastomosis procedure. Early and late complications occurred in 11 and 14%, respectively. There was one surgery-related death. Complications included cerebrospinal fluid leak (9%) and unsteadiness (9%). Conclusion: The TC and TO approaches provide access to midline intradural lesions, intradural petroclival tumors, and cerebellopontine angle tumors and cholesteatomas arising anterior to the internal auditory canal, without using brain retractors. Total tumor removal, including its base and blood supply, is possible. Facial weakness is frequent when the facial nerve is rerouted, but excellent facial nerve results are accomplished with the TO approach. With these approaches, recurrence israre when all tumor has been removed. Their safety and efficacy encourage their use in extensive lesions.

Endolymphatic Sac Shunt, Labyrinthectomy, and Vestibular Nerve Section in Meniere's Disease

Medical treatment for Menieres disease is effective in controlling vertigo for approximately 85% of patients. However, when disabling vertigo continues, surgical therapy is indicated. Several surgical approaches are performed to control the symptoms of peripheral vestibular disorders refractory to medical measures, each procedure having many technical variations. Surgery is usually reserved for patients with disabling vertigo. Here, the authors discuss surgical options for vertigo control in Menieres disease and review the literature on outcomes of these management options. The authors discuss endolymphatic sac shunt (ie, endolymphatic mastoid shunt), vestibular nerve section, cochleosacculotomy, and labyrinthectomy. When looking at data based on patient ratings, the authors find that surgery improves vertigo in endolymphatic sac shunt, vestibular nerve section, and labyrinthectomy groups and improves imbalance for the endolymphatic sac shunt and vestibular nerve section groups. Labyrinthectomy and translabyrinthine vestibular nerve section both offer excellent control of intractable vertigo. However, patients undergoing translab yrinthine vestibular nerve section are more likely to show improvement in imbalance and functional disability. This outcome is more likely for diagnoses other than Menieres disease. There are potential prognostic factors that can be helpful in the preoperative or postoperative counseling of patients undergoing surgical treatment of vertigo. Patients who rate themselves as more disabled before surgery are less likely to achieve the best outcomes. Several other factors, such as duration of disease, contralateral tinnitus, eye disease, and allergy, may play a role.

Surgical treatment for vertigo: patient survey of vertigo, imbalance, and time course for recovery.

OBJECTIVES: To assess surgical treatment of vertigo by patient ratings of postoperative vertigo, imbalance, and timing of symptom improvement. METHODS: A total of 3637 surgeries for vertigo were performed since 1974. Questionnaires sent to a random sample of patients operated since 1994 were completed by 28 endolymphatic sac shunt (ES), 54 vestibular nerve section (VNS), and 14 labyrinthectomy patients. RESULTS: All groups rated current vertigo characteristics and AAO-HNS disability as improved (all P ≤ 0.001), though “spinning dizziness” remained in some patients in each group. The ES and VNS groups rated all characteristics of imbalance as improved (all P ≤ 0.001), but it remained present in the majority. Vertigo resolved within 2 months in 75%, but some indicated months or even 1 to 2 years before attacks stopped. CONCLUSIONS: Based on patient ratings, surgery improved vertigo in all surgical groups and improved imbalance for ES and VNS groups. Imbalance will likely remain after surgery for vertigo. Patients should be informed that symptoms may not immediately resolve.