Mastoid obliteration with hydroxyapatite vs. bone pâté in mastoidectomy surgery performed on patients with cholesteatoma and chronic suppurative otitis media: a retrospective analysis.

PURPOSE: To compare the efficacy and safety of hydroxyapatite vs. bone pâté as obliteration material in mastoidectomy surgery for patients with chronic suppurative otitis media and cholesteatoma. METHODS: This is a retrospective, multi-center, cohort study. All patients were followed up with micro-otoscopy, audiometry, and, if indicated, MRI with diffusion-weighted imaging. The following outcome parameters were analyzed: procedure safety (wound infections and complications), cholesteatoma recidivism rates (residual/recurrent), control of infection (Merchant's scale), and hearing results (pure-tone averages at 500/1000/2000/4000 Hz). RESULTS: Eighty-three cases were included: 45 obliterated with hydroxyapatite and 38 with bone pâté, with a mean follow-up time of, respectively, 25 and 24 months. Wound infections were only detected in the bone pâté group (4.8%) and successfully treated with oral or intravenous antibiotics and surgical drainage (p = 0.026). No other major surgical complications were observed in both groups. Cholesteatoma recidivism was observed in 15% using hydroxyapatite and 12% using bone pâté (p = 0.471). Complete control of infection (Merchant 0) was achieved in 76.2% using bone pâté and 86.8% using hydroxyapatite at 12 months postoperatively (p = 0.223). All patients showed good postoperative healing without complete failure to manage infection (Merchant 3). Pre- and postoperative audiometry showed significant improvement in hearing results in both groups. No significant difference between the obliteration materials was observed. CONCLUSIONS: Evaluation of mastoid obliteration reveals that hydroxyapatite and bone pâté are safe and effective obliteration materials, with high success rates in achieving a dry ear, low recidivism rates, and good hearing outcome, respecting the short-term limitation. In addition, our study shows that hydroxyapatite results in fewer postoperative wound infections compared to bone pâté.

Measuring plasma exudation in nasal lavage fluid and in induced sputum as a tool for studying respiratory tract inflammation.

We performed nasal lavage (NAL) combined with induced sputum to determine exudative inflammation in the upper and lower airways in patients with chronic sinusitis and in controls. To monitor plasma exudation into the respiratory lumen and loss of size-selectivity of the mucosa, we determined the sample-to-serum ratio of albumin and alpha-2-macroglobulin, Qa1b and Qa2m, and the dilution independent Relative Coefficient of Excretion, RCE=Qa2m/Qa1b. To detect low protein levels in NAL and induced sputum we adapted an ELISA system for alpha-2-macroglobulin described by Out et al. [Clin. Chim. Acta, 165 (1987) 277-288], and modified this into a sensitive ELISA for albumin. Dithiothreitol, added to increase sputum solubility, did not interfere with the analysis, nor did N-ethylmaleimide, added to block dithiothreitol. In this study plasma exudation in induced sputum is significantly increased in patients with chronic sinusitis, compared to controls. Plasma exudation in NAL is also increased in patients, although not significant. The RCE in NAL and sputum is well-correlated in one of the three study visits. There is much variation in sample protein-levels partly due to differences in dilution and the heterogeneity of the studied population. Determination of plasma exudation together with RCE in NAL and induced sputum is a good, non-invasive way to quantify inflammation of airway mucosa.

National differences in incidence of acute mastoiditis: relationship to prescribing patterns of antibiotics for acute otitis media?

BACKGROUND: Operating on the principle that most acute otitis media (AOM) episodes resolve without antibiotics, doctors in the Netherlands usually manage AOM in children with initial observation. Prescription of antibiotics is limited to children with a complicated course of AOM and those categorized as high risk. Consequently only 31% of patients with AOM receives antibiotics, compared with >90% in most other countries. OBJECTIVE: To substantiate the suggestion that this restrictive use of antibiotics leads to a higher incidence of acute mastoiditis. METHODS: A comparative study across several European countries, Canada, Australia and the United States was performed in the period 1991 to 1998. The incidence rate of acute mastoiditis was defined as the total number of patients age 14 years and younger discharged from all hospitals with the primary diagnosis of acute mastoiditis, during a specified period (usually 5 years), divided by the number of person years (py) in that same age range and period. The latter was calculated by totaling the midyear population estimate of children age 14 years and younger of each year. The 95% confidence intervals and incidence rate ratios were calculated to compare the observed rates. RESULTS: The incidence rate of acute mastoiditis in the Netherlands, with a low antibiotic prescription rate for AOM, was 3.8/100,000 py; in Norway and Denmark, with high prescription rates, the incidence rate was comparable at 3.5/100,000 py and 4.2/100,000 py, respectively. In all other countries with very high prescription rates, incidence rates were considerably lower, ranging from 1.2 to 2.0/100,000 py. The incidence rate in the Netherlands was about twice that in the United States (rate ratio, 0.5). CONCLUSION: The incidence rate of acute mastoiditis in the Netherlands is higher than in many countries with higher antibiotic prescription rates. Although the potential benefits of restricted use of antibiotics (i.e. cost reduction, fewer side effects from antibiotics and less antimicrobial resistance) are beyond dispute, such strategy may be associated with a somewhat higher incidence of acute mastoiditis.

Nonsyndromic hearing impairment is associated with a mutation in DFNA5.

Nonsyndromic hearing impairment is one of the most heterogeneous hereditary conditions, with more than 40 loci mapped on the human genome, however, only a limited number of genes implicated in hearing loss have been identified. We previously reported linkage to chromosome 7p15 for autosomal dominant hearing impairment segregating in an extended Dutch family (DFNA5). Here, we report a further refinement of the DFNA5 candidate region and the isolation of a gene from this region that is expressed in the cochlea. In intron 7 of this gene, we identified an insertion/deletion mutation that does not affect intron-exon boundaries, but deletes five G-triplets at the 3' end of the intron. The mutation co-segregated with deafness in the family and causes skipping of exon 8, resulting in premature termination of the open reading frame. As no physiological function could be assigned, the gene was designated DFNA5.

Refined mapping of a gene for autosomal dominant progressive sensorineural hearing loss (DFNA5) to a 2-cM region, and exclusion of a candidate gene that is expressed in the cochlea.

A gene for an autosomal dominant form of progressive sensorineural hearing loss (DFNA5) was previously assigned by us to a 15-cM region on chromosome 7p15. In this study, the DFNA5 candidate region was refined to less than 2 cM, and completely cloned in a YAC contig. The HOXA1 gene located in 7p15 was considered to be a good candidate gene for DFNA5 as it harbours mutations leading to developmental defects of the inner ear in mice. However, the refinement of the candidate region of DFNA5 excludes the HOXA1 gene as a candidate for DFNA5. We cloned a novel candidate gene (CG1, candidate gene 1), which is expressed in human fetal cochlea, from the DFNA5 candidate region. The complete cDNA sequence of CG1, encoding a 423 amino acid protein of unknown function, was determined. Mutation analysis of the CG1 gene in DFNA5 patients, however, could not reveal a disease-causing mutation.