2b Laryngoscope, 127:2389-2395, 2017.
To study the effects of viable and heat‐killed Moraxella catarrhalis bacteria on the middle ear mucosa and to evaluate the protection after whole‐cell immunizations, Sprague‐Dawley rats were challenged and rechallenged with four different M. catarrhalis strains. The animals were monitored by clinical observations, bacterial and histological samples from middle ears, and serum IgG levels. Only viable bacteria at a high concentration induced purulent otitis media, which was culture positive in 58% of the cases on day 4. The infection was characterized by a mild acute reaction lasting otomicroscopically about 8 days, together with quantitative and qualitative changes of the goblet cells. Structurally the mucosal effects of the heat‐killed bacteria were less pronounced in the early phase compared to the viable bacteria, but similar at the end of the experiment at 6 months. The intrabullar and subcutaneous immunizations evoked an IgG antibody response in all animals, and the protection rate after immunization was 50% or more. The induced protection was not strain‐specific. The study showed the rat to be a possible alternative for the study of different aspects of M. catarrhalis otitis media, an infection that is clinically and structurally different from that elicited by Streptococcus pneumoniae and Haentophilus influenzae in the rat.
Objectives/Hypothesis Postoperative tinnitus and taste disturbances after myringoplasty are more common than previously reported. Study Design This study was a retrospective analysis of prospectively collected data from the Swedish National Quality Registry for Myringoplasty. Methods The analysis was performed on extracted data from all counties in Sweden collected from database A from 2002 to 2012 and database B from 2013 to 2016. Tinnitus and taste disturbance complications 1 year after myringoplasty were analyzed in relation to gender, age, procedure, and success rate. In database A, physicians reported tinnitus and taste disturbances. In database B, patients reported the complications. Results A major difference was found when the complications were reported by physicians compared to when the complications were reported by patients. In database A, tinnitus was reported in 1.2% of the patients and taste disturbances in 0.5%. In database B, the frequencies were 12.3% and 11.2%, respectively. Tinnitus and taste disturbances were more frequent after conventional myringoplasty compared to those after fat grafting and were more frequent after primary compared to those after revision surgery when reported by physicians. Patients, however, reported the same frequency of tinnitus after fat graft myringoplasty compared to that after conventional myringoplasty (12.0% vs. 12.6%) and fewer taste disturbances after revision surgery. In follow‐up assessments, complications persisted after surgery over a long time period. Conclusion Tinnitus and taste disturbances are more common after myringoplasty when patients report their symptoms than when physicians report the symptoms. Level of Evidence 2b Laryngoscope, 129:209–215, 2019
Acute otitis media (AOM) is the most common reason for outpatient antimicrobial therapy. Mixed infections pose a potential problem, since the first-line drug used for the treatment of AOM, amoxicillin, can be neutralized by -lactamase-producing pathogens of the upper respiratory tract. To study the effects of a 5-day course of amoxicillin on a mixed middle ear infection, rats were challenged with Streptococcus pneumoniae alone or in combination with -lactamase-producing nontypeable Haemophilus influenzae. Amoxicillin was introduced at the clinical peak of the infection. Local and systemic changes were monitored by otomicroscopy, bacterial culture, and analysis of histological changes and the expression of the transforming growth factor beta (TGF-) gene. -Lactamase-producing H. influenzae did not demonstrate an ability to protect S. pneumoniae. Amoxicillin eradicated the pneumococci in all treated animals but increased to some degree the ability of H. influenzae to persist at the site of infection. Thus, only an insignificant acceleration of the resolution of the AOM caused by a mixture of pathogens was observed during treatment. Moderate to major morphological changes could not be avoided by treatment of the mixed infections, but a slight downregulation of TGF- expression was observed. In contrast to infections caused by a single pathogen, the mixed infections induced white plaques in the tympanic membrane at a remarkably high frequency independent of treatment. These experimental findings constitute support for further studies of antimicrobial drugs and AOM caused by bacteria with and without mechanisms of antibiotic resistance.Acute otitis media (AOM) is one of the most common bacterial infections in pediatric patients. The predominant pathogens causing AOM are Streptococcus pneumoniae, Haemophilus influenzae, and Moraxella catarrhalis (22). Of these three agents S. pneumoniae has the lowest spontaneous clearance rate, and it is the microorganism most often associated with severe and fatal complications of AOM (1,18,25). As a consequence, the antimicrobial drug used for the treatment of AOM in routine practice must have a spectrum which covers this bacterium to be efficacious.Hitherto, amoxicillin has been the first-line therapeutic choice in several countries (10,14). Its pharmacokinetic and pharmacodynamic profiles are attractive, but its utility is sometimes compromised by an increasing proportion of -lactamresistant isolates. About 14 to 65% of the nontypeable (NT) H. influenzae isolates from the middle ear produce -lactamase (16,20,22,24). For M. catarrhalis isolates the frequency is virtually 100% (20,22,24). Because of the high rate of -lactamase production in these two species, the use of -lactamase-resistant drugs such as macrolides and trimethoprimsulfamethoxazole is often recommended (9). However, many of these antibiotics are not entirely effective as empirical treatment for AOM, especially macrolides for the treatment of infections caused by NT H. influenzae, and they may increase the rat...
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