Factors Associated with Clinical Outcomes in Acute Otitis Media

Acute otitis media (AOM) is a common disease in childhood. If predictors of outcome in AOM were known, it would be possible to individualize therapy. Our aim was to identify factors that predict the outcome in AOM. We enrolled 368 children with AOM (ages, 10 to 86 months). The severity of symptoms and the severity of tympanic membrane changes were graded with a scoring system. Nasopharyngeal colonization with middle ear pathogens was determined on day 1. Three outcomes were assessed: persistence of symptoms at day 5, persistence of tympanic membrane changes at day 28, and recurrence of acute symptoms prior to day 28. Persistence of symptoms at day 5 was associated with younger age (35 versus 44 months; p < .001), higher symptom score on day 1 (3.5 versus 2.9; p < .05), and colonization with Streptococcus pneumoniae (61% versus 41%; p < .05). Persistence of tympanic membrane changes at day 28 was associated with younger age (39 versus 45 months; p < .01), higher tympanic membrane score on day 1 (4.1 versus 3.6; p < .01), and nasopharyngeal colonization with S pneumoniae, especially drug-resistant S pneumoniae (33% versus 13%; p < .05). Recurrence of acute symptoms prior to day 28 occurred in 14% of the children. Streptococcus pneumoniae was the only pathogen associated with an increased recurrence rate (23%) as compared to the group without pathogens (7%; p < .05). Age, severity of disease at presentation, and nasopharyngeal colonization patterns were proven to be important determinants of outcome in AOM.

Factors affecting loss of tympanic membrane mobility in acute otitis media model of chinchilla

Recently we reported that middle ear pressure (MEP), middle ear effusion (MEE), and ossicular changes each contribute to the loss of tympanic membrane (TM) mobility in a guinea pig model of acute otitis media (AOM) induced by Streptococcus pneumoniae (Guan and Gan, 2013). However, it is not clear how those factors vary along the course of the disease and whether those effects are reproducible in different species. In this study, a chinchilla AOM model was produced by transbullar injection of Haemophilus influenzae. Mobility of the TM at the umbo was measured by laser vibrometry in two treatment groups: 4 days (4D) and 8 days (8D) post inoculation. These time points represent relatively early and later phases of AOM. In each group, the vibration of the umbo was measured at three experimental stages: unopened, pressure-released, and effusion-removed ears. The effects of MEP and MEE and middle ear structural changes were quantified in each group by comparing the TM mobility at one stage with that of the previous stage. Our findings show that the factors affecting TM mobility do change with the disease time course. The MEP was the dominant contributor to reduction of TM mobility in 4D AOM ears, but showed little effect in 8D ears when MEE filled the tympanic cavity. MEE was the primary factor affecting TM mobility loss in 8D ears, but affected the 4D ears only at high frequencies. After the release of MEP and removal of MEE, residual loss of TM mobility was seen mainly at low frequencies in both 4D and 8D ears, and was associated with middle ear structural changes. Our findings establish that the factors contributing to TM mobility loss in the chinchilla ear were similar to those we reported previously for the guinea pig ears with AOM. Outcomes did not appear to differ between the two major bacterial species causing AOM in these animal models.

[Peculiarities of clinical course of chronic purulent epitympanitis]

Wide application of antibiotics in bacterial infections have caused selection and prominent dissemination occurrence of antibioticoresistant strains of microorganisms. Etiological and pathogenetic peculiarities of chronic purulent epitympanitis (CHPE) were studied, rational curative scheme of 69 therapy patients was elaborated, which included sanation, the earpreserving operations on middle ear, performed for CHPE.

Otogenic cerebellar abscess: a case report

This case report describes the gradual deterioration of a healthy, highly functioning man who initially presented with a draining right ear. The patient's indolent neurologic decline and referral to an otologist ultimately led to the diagnosis and treatment of an otogenic cerebellar abscess, an increasingly rare intracranial complication of otitis media. We report this case to illustrate that severe complications of chronic otitis media still occur in the United States, to stress the importance of clinical suspicion in the postantibiotic era, and to review the literature regarding the most appropriate time to perform the otologic portion of the surgery.

Aspergillus otomycosis in an immunocompromised patient

Aspergillus niger, an opportunistic filamentous fungus, was identified as the cause of chronic unilateral otomycosis in a 55-year old, immunocompromised man who had been unresponsive to a variety of treatment regimens. The patient presented with intermittent otalgia and otorrhea and with a perforation of his left tympanic membrane. A niger was identified in a culture specimen obtained from the patient's left ear canal. In immunocompromised patients, it is important that the treatment of otomycosis be prompt and vigorous, to minimize the likelihood of hearing loss and invasive temporal bone infection.

[Establishment of tympanosclerosis by intratympanic injection of Staphylococcus aureus in guinea pigs]

OBJECTIVE

To establish a guinea pig model of tympanosclerosis and investigate the development and progression of tympanosclerosis in the tympanic membranes and middle ear mucosa.

METHODS

Twenty-one healthy guinea pigs were subjected inoculation of 1x10(8)/L Staphylococcus aureus into the left middle ear cavities under general anaesthesia, with the right ears as the control, to establish models of chronic purulent otitis media. The animals were sacrificed by decapitation after 1, 3 and 6 months after model establishment for histological examination of the middle ear mucosa.

RESULTS

The histological changes of tympanosclerosis occurred in some of the animals 3 months after model establishment, and the extent of calcium deposition and fibrosis across the mucosa were positively correlated with the duration of chronic purulent otitis media.

CONCLUSION

Tympanosclerosis may occur in some guinea pigs after inoculation of Staphylococcus aureus into the middle ear cavity, and this model can be useful for study of tympanosclerosis.

Prediction of upper respiratory tract bacteria in acute otitis media

CONCLUSIONS

Thorough otomicroscopical examination of the tympanic membrane in acute otitis media (AOM) might distinguish AOM episodes caused by different bacteria. It thus might be a way to select appropriate treatment for each patient without raising the number of dangerous complications.

OBJECTIVES

The aim of this study was to see if it might be possible to predict the causative bacterium by judging the otomicroscopical appearance of the tympanic membrane in episodes of AOM.

PATIENTS AND METHODS

The study was prospective. Patients suffering from non-perforated AOM were included. The tympanic membrane was photographed. A prediction of the causative bacterium was made and tympanocentesis was performed. Effusion from the middle ear and a nasopharyngeal swab were obtained for bacterial culturing. The causative bacteria were categorized into gram-positive (Streptococcus pneumoniae and S. pyogenes) or gram-negative (non-typable Haemophilus influenzae and Moraxella catarrhalis).

RESULTS

A total of 82 patients were included in the study. A correct prediction was made in 47/63, a false prediction in 16/63 (kappa 0.48, p<0.001).

Otomicroscopic findings and systemic interleukin-6 levels in relation to etiologic agent during experimental acute otitis media

The aim of the present study was to explore whether it was possible to differentiate the clinical course and the otomicroscopic appearance of acute otitis media (AOM) caused by common otitis pathogens in an animal model. Systemic interleukin (IL)-6 levels as early markers for bacterial AOM were also studied. Four groups of rats were inoculated with either Streptococcus pneumoniae, Streptococcus pyogenes, non-typeable Haemophilus influenzae or Moraxella catarrhalis. The animals were monitored by otomicroscopy, photos of the tympanic membrane, cultures and IL-6 detection in serum the following 4 days. The gram-positive S. pneumoniae and S. pyogenes induced severe AOM with opaque effusion behind the tympanic membrane, pronounced dilation of the vessels and spontaneous perforations. The gram-negative H. influenzae and M. catarrhalis induced a less severe infection with cloudy, sometimes foamy effusion, and no spontaneous perforations. With the otomicroscopic findings it was possible to distinguish between infections induced by gram-positive bacteria and gram-negative bacteria. Detection of interleukin-6 in serum appeared to be of limited use for all infections except the pneumococcal AOM, but this needs to be further investigated.

Pseudomonas aeruginosa infection in the hypoventilated middle ear: an experimental model

CONCLUSION

This is a suitable model for studying different aspects of the pathophysiology of chronic suppurative otitis media.

OBJECTIVE

To analyze the methodological features of an animal model of chronic suppurative otitis media induced by intratympanic inoculation of Pseudomonas aeruginosa.

MATERIAL AND METHODS

Otitis media was induced by inoculation of P. aeruginosa through the inferior aspect of the rat bulla and cauterization of the Eustachian tube via a transpalatal approach. Inspection of the tympanic membrane, culturing of middle ear effusion and processing of the temporal bones for light microscopy were performed.

RESULTS

Abnormal otomicroscopic findings and persistence of infection were correlated with the histopathological changes found in middle ear tissues.

Otoscopic and tympanometric findings in acute otitis media yielding dry tap at tympanocentesis

BACKGROUND

The value of tympanometry in detection of middle ear effusion (MEE) has been widely studied in otitis media with effusion. There has been no direct comparison of tympanometric and tympanocentesis (TAP) findings in acute otitis media (AOM). We compared otoscopic, tympanometric and TAP findings in AOM including cases of AOM without effusion.

METHODS

In a study of AOM treatment of 90 children, a tympanogram was obtained, and TAP was performed before and after 5 days of treatment. Subjects were followed with otoscopy and tympanometry every 2 weeks for 3 months or until the MEE cleared.

RESULTS

In 130 AOM ears, otoscopic, tympanometric and TAP findings were available; MEE was obtained from 110 ears. Of 20 ears with a dry tap, 18 had abnormal tympanogram and otoscopic findings. With TAP findings as the standard, sensitivity and positive predictive value of type B tympanogram were 97 and 87%, respectively. Of 18 AOM ears yielding dry tap, 2 yielded MEE 5 days later, and 8 continued with evidence of MEE 5 days-12 weeks later. Five subjects with 8 AOM ears yielding dry tap were lost to follow-up; all had short duration of clinical symptoms.

CONCLUSIONS

Although otoscopic and tympanometric findings suggested the presence of MEE in AOM, MEE was unobtainable by TAP in 14% of cases. Dry tap cases likely represent early AOM before accumulation of detectable MEE. However, technical difficulty in obtaining small amounts of or highly viscous MEE could not be excluded. Sensitivity and positive predictive value of abnormal tympanograms in detection of MEE in AOM cases are comparable with those in otitis media with effusion.

Tuberculous otitis media: a significant diagnostic challenge

OBJECTIVE

This study was undertaken to revise the diagnostic characteristics of tuberculous otitis media (TOM), a disorder that is often diagnosed late, leading to delay in specific treatment.

STUDY DESIGN AND SETTING

Retrospective study of a longitudinal series of 10 TOM patients over a 7-year period at an institutional referral center.

RESULTS

Most patients showed intractable otorrhea, moderately severe hearing loss, and necrotic eardrums with granulation tissue and single perforations. Multiple perforations, facial palsy, and cervical adenopathies were rare (<10% of patients). CT generally showed soft tissue involvement of the middle ear without bone erosion. The most effective laboratory test microbiological culture of exudate (diagnostic efficacy 71%). Specific antibiotic treatment was effective in all cases.

CONCLUSION

The diagnosis of TOM remains a significant challenge for otorhinolaryngologists.

SIGNIFICANCE

If there are strong clinical grounds for suspicion, standard laboratory tests for tuberculosis should be repeated even if initially negative.

No evidence of Mycoplasma pneumoniae in acute myringitis

Our aim was to discover Mycoplasma pneumoniae in bullous and hemorrhagic myringitis in children <2 years of age. Middle ear fluid samples (n = 37) and samples taken from the blisters of the tympanic membranes (n = 12) studied by polymerase chain reaction for M. pneumoniae were negative. This study does not support an important role for M. pneumoniae as an etiologic agent in acute myringitis.

Trichophyton rubrum in the external auditory meatus. Fallbericht. Trichophyton rubrum im ausseren Gehorgang

We report the case of a 28-year-old immunocompetent male suffering from otitis externa. The right external auditory meatus was filled with cerumen and detritus, the tympanic membrane covered wallpaper-like with layers of fungi. Mycological analysis revealed Trichophyton rubrum. With further examination tinea pedis of plantar and interdigital type and concomitant onychomycosis of the toenails due to T. rubrum could be detected. The auditory meatus was cleaned and treated topically with clotrimazole. Two weeks later the auditory meatus and the tympanic membrane were bare of fungi and the inflammation was resolved. Treatment of tinea pedis and onychomycosis with terbinafine (systemically and topically) is still lasting.

Acute otitis media develops in the rat after intranasal challenge of Streptococcus pneumoniae

OBJECTIVES/HYPOTHESIS

The rat is a frequently used animal model for middle ear research. To date, acute otitis media (AOM) has been evoked after instillation of bacteria directly into the middle ear cavity or after traumatizing the tympanic membrane. The purpose of the study was to examine whether, with an intact tympanic membrane and middle ear cavity, intranasally deposited bacteria cause AOM and how tympanic membrane stimulation influences this procedure.

STUDY DESIGN

In vivo, murine model.

METHODS

In a rat model, Streptococcus pneumoniae, type 3, was intranasally inoculated for 5 consecutive days. The tympanic membrane was treated with saline or with compound 48/80 or was left untreated. The development of AOM was evaluated by otomicroscopy, light microscopy, and middle ear culture.

RESULTS

Ninety percent of the ears developed AOM. However, when the tympanic membranes were treated with saline or compound 48/80, only 40% and 57%, respectively, developed AOM. In all, 23 of 40 ears developed AOM and 20 ears showed growth of bacteria.

CONCLUSION

Repeated intranasal deposition of S. pneumoniae, type 3, causes AOM in the rat. The development of AOM can be influenced by tympanic membrane stimulation.

Pars flaccida displacement pattern in purulent otitis media in the gerbil

HYPOTHESIS

Our hypothesis is that purulent otitis media and otitis media with effusion cause stiffness loss of the tympanic membrane. This loss of stiffness may be persistent and precede the development of retraction pockets and cholesteatoma.

BACKGROUND

Postinflammatory changes such as retraction pockets and cholesteatoma develop in the pars flaccida and in the pars tensa of the tympanic membrane. In our previous experimental studies, stiffness changes were shown to develop early in the pars tensa in response to purulent otitis media and otitis media with effusion. These changes are suggested to be precursors to a later development of retraction pockets and cholesteatoma. In the clinical situation, retraction pockets are often found in the pars flaccida only. The aim of the current study was thus to investigate whether stiffness changes appear also in the pars flaccida during purulent otitis media.

METHODS

Streptococcus pneumoniae type 3 was injected into the middle ear to induce purulent otitis media. As a measure of pars flaccida stiffness, peak displacement versus middle ear pressure was used. The peak displacement measurements were obtained from full-field moiré; interferometry, which is a noncontacting optical technique for deformation measurements.

RESULTS

Ears with purulent otitis media showed increased peak displacement of the pars flaccida at a middle ear pressure of 200 daPa, compared with normal controls.

CONCLUSION

There was a decreased mechanical stiffness of the pars flaccida in acute purulent otitis media. This decreased stiffness may predispose for future retraction pocket formation and cholesteatoma development.

Concomitant otomycosis and dermatomycoses: a clinical and microbiological study

Otomycosis tends to recur despite long-term treatment. To our knowledge, there is no study in the English literature concerning the clinical importance of concomitant otomycosis and dermatomycoses. We investigated the presence of dermatomycoses in 52 patients with otomycosis in order to document the clinical and microbiological importance of their coexistence. Dermatomycoses on the feet and/or hands were identified in 19 patients (36.5%). The most common pathogen for otomycosis was Aspergillus niger, while it was Candida albicans for the dermatomycoses. The same pathogenic fungi were isolated from the otomycosis and dermatomycoses in nine of the 19 patients (47.4%). Aspergillus niger was the most common shared pathogen. The pathogens isolated in concomitant dermatomycoses were common pathogens for the fungal infection of the ear ( Aspergillus niger, Aspergillus flavus, Aspergillus fumigatus, Candida albicans). It was concluded that the autoinoculation of the ear canal by pathogenic fungi might be possible in the presence of the untreated dermatomycoses. Dermatomycoses must be investigated in patients with otomycosis and must be treated simultaneously in order to prevent the recurrence of both.

Outcome of acute otitis media and its relation to clinical features and nasopharyngeal colonization at the time of diagnosis

Children (n = 115; age range 1-9 years) with a diagnosis of acute otitis media (AOM) were eligible for this study and were enrolled within 24 h of the onset of symptoms/signs. A nasopharyngeal culture was obtained at the initial visit. Children were treated with a single oral antibiotic for 7 days. Changes in symptoms/signs and tympanic membrane features assessed by a scoring system were monitored for 1 month and related to the nasopharyngeal pathogen recovered on Day 1. More than 80% of children had no symptoms/signs by Day 3, and 60% of cases had normal tympanic membranes by Day 29. Children without any symptoms/signs on Day 3 had significantly lower symptom/sign scores on Day 1 (p = 0.005). Seventy-nine percent of cases carried middle ear pathogens in the nasopharynx at diagnosis: Streptococcus pneumoniae (48%); Haemophilus influenzae (24%); and Moraxella catarrhalis (16%). Children with S. pneumoniae showed significantly higher tympanic membrane scores than children with no pathogen at Days 8, 15 and 29 (p < 0.01 for each comparison). Multivariate regression analysis revealed that lower tympanic membrane score on Day 1, the absence of S. pneumoniae in the nasopharynx and treatment with amoxillin were independent factors for rapid normalization of the tympanic membrane. These data suggest that the clinical course of AOM may be predicted, in part, at the time of diagnosis by means of careful evaluation of symptoms/signs and the tympanic membrane as well as knowledge of pathogens harbored in the nasopharynx.

Acute mastoidectomy in a Danish county from 1977 to 1997--operative findings and long-term results

Data from patients undergoing acute mastoidectomy were examined retrospectively to evaluate if the nature of acute mastoiditis (AM) treated surgically has changed during the last 20 years (1977-97). Moreover, a prevalence study was conducted to clarify the otological and audiological course following acute mastoidectomy. Patients with cholesteatoma and intracranial complications were excluded. Thus, 79 patients with a median age of 16 months were included. Thirty-seven percent had a history of middle ear disease, and the mean duration from onset of symptoms to admission was 9 days. Well-being was affected in 46%, and 82% had fever. The clinical picture was dominated by auricular protrusion (77%) and pathological tympanic membrane (94%). Postauricular oedema, hyperaemia and tenderness were demonstrated in 89%, 78% and 49% of cases, respectively. Peroperatively, purulent middle ear effusion was recognized in 92%, subperiosteal abscess in 66% and pus in the mastoid in 90%. Specimens revealed growth of pathogens in 58%, predominantly Gram-positive bacteria. The observation period was 1-20 years. The findings in operated ears were not significantly different from the contralateral non-operated ears concerning incidence of otitis media, hearing and ear canal volume. Conclusively, acute mastoidectomy is a safe and effective treatment to eliminate infection. The operation can be done with negligible risk and does not leave long-term sequelae.

Middle ear effusions and structure of the tympanic membrane

OBJECTIVE

To study the effect of various middle ear effusions on the structure of the lamina propria of the tympanic membrane.

METHODS

Sterile and infective middle ear effusions were induced by obstruction of the eustachian tube in specific pathogen-free (SPF) rats and in rats with upper airway infections (URI), respectively. The condition of the tympanic membrane was monitored at regular intervals. After varying survival times, the animals were killed and the tympanic membranes processed for light and electron microscopy.

RESULTS

Sterile effusions always resulted in tympanosclerotic lesions. These lesions did not develop in the presence of primary-infected effusions. These effusions had a severe destructive effect on the lamina propria, followed by fibrosis. Generally, secondary infection did not markedly affect preexisting tympanosclerotic lesions. Moreover, calcification disappeared when re-aeration of the middle ear occurred, but the abnormal collagen depositions persisted.

CONCLUSIONS

Both sterile and infective effusions result in comprehensive irreversible changes in the lamina propria of the pars tensa. The development of tympanosclerosis is confined to sterile effusions. Mechanical injury and compromised vascularization of the lamina propria are likely to be important etiological factors in the development of tympanosclerosis.

Chronic myringitis: prevalence, presentation, and natural history

OBJECTIVE

The aim of this study was to examine the clinical presentation and natural history of chronic myringitis (CM).

STUDY DESIGN

Retrospective case review.

SETTING

Tertiary referral center.

PATIENTS

Chronic myringitis is defined as a loss of tympanic membrane epithelium for >1 month without disease within the tympanic cavity. Seven hundred fifty patient records were reviewed to determine the prevalence of CM in an academic otology practice. The records of 40 patients (45 ears) with CM seen between 1995 and 1999 inclusive were reviewed.

MAIN OUTCOME MEASURES

The series was reviewed with attention to previous medical and otologic history, the nature and duration of symptoms, the physical findings, and management.

RESULTS

The prevalence of CM was found to be -1% (approximately one fourth as common as cholesteatoma). Symptoms were often present for many years before the diagnosis of CM, with CM often mistaken for chronic otitis media. Sixty percent of patients had undergone previous otologic procedures. There did not appear to be an association between CM and systemic disease. Physical findings were varied, with granulation tissue and tympanic membrane perforations often occurring transiently. The clinical course of CM is typified by recurrent episodes of symptoms, often interspersed with long asymptomatic periods. A subset of CM can result in an acquired atresia. The most effective treatment appeared to be prolonged topical medications, surgery being reserved for only the most refractory cases.

CONCLUSIONS

Chronic myringitis is often mistaken for chronic otitis media. Such confusion prolongs the initiation of appropriate management and sometimes leads to needless tympanomastoid surgery. The otologist should be aware of this clinical entity and its varied presentation.

Cell biology of tubotympanum in relation to pathogenesis of otitis media - a review

The sterility of the eustachian tube and tympanic cavity of normal individuals is maintained not only by the adaptive immune system, but also by the mucociliary system and the antimicrobial molecules of innate immunity. Mucin production and periciliary fluid homeostasis are essential for normal mucociliary function and dysfunction of this system is an important risk factor for otitis media. The secreted antimicrobial molecules of the tubotympanum include lysozyme, lactoferrin, beta defensins, and the surfactant proteins A and D (SP-A, SP-D). Defects in the expression or regulation of these molecules may also be the major risk factor for otitis media.

Clinicomicrobiologic evaluation of active tubotympanic type chronic suppurative otitis media

OBJECTIVES

This prospective study was conducted to determine the spectrum of micro-organisms encountered in patients with active-stage chronic suppurative otitis media (CSOM) (tubotympanic type) and to see whether prescribing an antibiotic after culture sensitivity was more beneficial as compared to initial treatment without cultures.

DESIGN

Prospective randomized study of 110 patients of active CSOM (tubotympanic type) divided into two groups of 55 cases each.

SETTING

Departments of Ear, Nose and Throat and Microbiology of a tertiary care hospital.

METHODS

The patients in group A were prescribed an antibiotic according to the culture and sensitivity, whereas in group B, culture was not done at the first visit, and a broad-spectrum antimicrobial, namely, co-trimoxazole, was prescribed blindly for a maximum period of 2 weeks. The cases that still had ear discharge were then subjected to culture and sensitivity and the antibiotic was prescribed accordingly.

MAIN OUTCOME MEASURES

All patients in group A were subjected to bacterial culture and sensitivity and fungal culture. Only failed cases in group B were subjected to the same.

RESULTS

In group A, 47 patients (85.50%) had positive bacterial culture and 20 patients had positive fungal culture. Pseudomonas aeruginosa was the most common bacterial isolate. All of these 47 patients had a dry ear with a maximum 2 weeks of antibiotic therapy. Among the remaining 8 patients who had negative bacterial culture, 5 patients (9.0%) showed fungal isolates on culture and responded to topical antifungal treatment. The remaining 3 failed cases (5.5%) responded to daily dry mopping alone. In group B, 41 patients (74.54%) attained a dry ear. Bacterial culture and sensitivity were done in the remaining 14 (25.46%) failed cases. The culture was positive in 11 patients (20.0%) and sterile in 3 patients (5.5%). In the latter group, only 1 patient had fungus on culture and the remaining 2 patients responded to daily dry mopping alone, which was done at a maximum for a week only. The most common fungal pathogen isolated was Aspergillus flavus.

CONCLUSIONS

Pseudomonas aeruginosa was the most common bacteria and Aspergillus flavus the most common fungus isolated in this study. In group A patients, the failed cases were less as compared to the control group B, but the p value was .2. Hence, there is no definite role of culture and sensitivity in the initial management plan of all cases of CSOM. Ideally, every such case should be prescribed a broad-spectrum antibiotic and only in failed cases should culture and sensitivity be done.

Induction of temporary otitis media in specific-pathogen-free pigs by intratympanic inoculation of Mycoplasma hyorhinis

OBJECTIVE

To examine whether Mycoplasma hyorhinis inoculated into the tympanic cavity can cause otitis media in pigs.

ANIMALS

17- or 22-day-old specific-pathogen-free pigs.

PROCEDURE

Histologic and bacteriologic examinations were performed on specimens from the tympanic cavity and auditory tube at 0, 7, 14, and 25 days after intratympanic inoculation of M hyorhinis (auditory tube cloning strain 14).

RESULTS

In M hyorhinis-inoculated pigs, mild to moderate inflammation of the auditory tube and tympanic cavity first appeared at postinoculation day (PID) 7. In pigs euthanatized at PID 14, the degree of inflammation was aggravated. Immunohistochemical analysis revealed M hyorhinis antigens on the luminal surface of the auditory tube and tympanic cavity. By PID 25, lesions had lessened. By use of transmission and scanning electron microscopic examinations, mycoplasmal organisms were identified among the cilia in the auditory tubes at PID 14 but not at PID 25. Results of bacteriologic examination indicated that 10(4) to 10(6) color-changing units of M hyorhinis were isolated from the tympanic cavity at PID 0. Variable numbers of M hyorhinis were isolated at PID 7 and 14, and numbers were decreased at PID 25.

CONCLUSIONS

M hyorhinis inoculated into the tympanic cavity can cause a self-limiting otitis media in SPF pigs.

Mast cell clusters in pars tensa membranae tympani in acute otitis media: a possible role in perforation healing

Mast cells are known to reside in pars flaccida membranae tympani and other parts of the middle ear mucosa in both rats and humans. However, the normal pars tensa contains no or only a few mast cells along the manubrial vessels. We examined the pars tensa of 25 rats in an experimental model of acute otitis media and found 13 mast cell clusters in 6 membranes. A majority of clusters were located in the anterior, superior quadrant and contained from 3 to 23 cells. The mast cells resided immediately under the inner epithelial lining or in the intermediate, fibrous layer. In two membranes mast cell clusters were found in the margin of apparently healed spontaneous perforations. We conclude that mast cells in some cases infiltrate pars tensa membranae tympani in the late and receding phase of acute otitis media. As these cell clusters in some cases were found immediately around apparently healed membrane perforations, we propose that the mast cell might participate in the repair processes of tympanic membrane perforation healing. This is supported by recent studies in wound healing and functions of a number of mast cell mediators.

Incudal folds and epitympanic aeration

Thirty-seven temporal bones were dissected, and the posterior tympanic and epitympanic folds recorded and photographed. Histologic details were documented from four serially sectioned temporal bones, two normal and two inflamed. Of these 41 specimens, 31 were normal, and 10 showed signs of inflammation. The type for the lateral fold was incudomalleal in 16 and incudal in 25 ears. Incus intercrural and incudostapedial folds appeared only exceptionally. Medial and superior incudal folds were not present in normal ears. The anterior tympanic isthmus was a constant, large aeration pathway. In chronically inflamed ears, its partial or total block was caused by polypoid or large sheet-like folds. Inactive sequelae appeared as mature, simple, one-layer or extensive multilayer networks of webs, connected with a deeply indrawn incudomalleal fold. The small posterior isthmus was open to the incudal fossa in 13 ears, and in 28, it was sealed off by a posterior incudal fold. The mastoid air cell tracks were (in ten of 37 dissected ears) open to the incudal fossa, or directly, to the posterior tympanum. Auxiliary pathways due to membrane defects were found in both the horizontal and descending portions of the incudomalleal fold. Excepting the chordal, incudomalleal, and posterior incudal folds, fold-like webs in the posterior tympanum and epitympanum are of inflammatory origin.

The incidence of bacteria in middle ear effusions

Otitis media with effusion (OME) is a common condition in paediatric ENT practice. Whilst surgical management is in many cases the mainstay of treatment for resistant OME, the use of antibiotics has been advocated by some authorities. Over one quarter of middle ear effusions analysed in this study contained potentially pathogenic bacteria. Antibiotics may be of value in the treatment of OME in these children.

Moraxella (Branhamella) catarrhalis-induced experimental otitis media in the chinchilla

Otitis media was introduced in chinchillas by direct transbullar inoculation with either viable or formalin-inactivated Moraxella (Branhamella) catarrhalis. Both groups of animals developed middle ear fluids (MEF) and severe inflammatory changes in the tubotympanum. Pure cultures of M. catarrhalis were recovered for up to 5 days after inoculation from those animals inoculated with viable bacteria. Significantly elevated anti-M. catarrhalis antibody titers were detected in post-inoculation sera and in MEF or bullar lavages, and an increased number of IgG-bearing cells was also observed in the tubotympanum of these animals. Control chinchillas inoculated with pyrogen-free sterile saline failed to show any signs of otitis media. Our data indicate that viable M. catarrhalis induce acute otitis media in the chinchilla but that the bacteria are rapidly eliminated from the middle ear, precluding its usefulness as a model to study acute otitis media. Moreover, the same concentration of nonviable organisms also induces severe inflammatory changes in the middle ear. These data indicate that the chinchilla may be a useful model for studying the role of nonviable M. catarrhalis or its cell wall components on the induction and persistence of inflammation in the middle ear.

Facial paralysis secondary to tympanic mucormycosis: case report

Mucormycosis is a saprophytic fungal disease. In the region of the head, it has been recognized to invade nasal cavity, paranasal sinus, orbit, or intracranial structures. However, unique involvement of the middle ear, with facial paralysis, still remains unreported. An unusual experience with a diabetic who developed this disease is described. Surgical debridement and amphotericin B administration resulted in near-total cure. The significance of this report is to add a new site involved by mucormycosis, that is, the tympanic cavity.

Calcium oxalate crystal deposition in necrotizing otomycosis caused by Aspergillus niger

Numerous calcium oxalate crystals were present within fruiting heads of Aspergillus niger and among necrotic debris in a case of bilateral invasive otomycosis occurring in a diabetic female with end stage renal disease. This is the first report of in vivo calcium oxalate crystal deposition associated with Aspergillus niger at this anatomic site. The presence of localized oxalate crystals within necrotic tissue from the external auditory canal is presumptive of otomycosis caused by Aspergillus niger, and may serve as a diagnostic clue to the etiologic agent before histologic demonstration of hyphae or growth in culture.

Cytological and histological changes in the middle ear after inoculation of influenza A virus

Experimental otitis media induced in the chinchilla by inoculation of influenza A virus into the middle ear resulted in capillary engorgement, subepithelial hemorrhage, tissue edema and acute inflammatory cell infiltration. Quantitative morphometric measurements were made for 28 days. Ciliated cells appeared to be the primary target of this strain of influenza virus and demonstrated the greatest degree of damage. Three weeks were required to restore the ciliated epithelium in the tubotympanum to normal levels.

Bacteriology of acute otitis media: a new perspective

Pathogenic bacteria were isolated from 90% of patients with acute otitis media. This higher-than-expected rate of positive cultures was probably related to the meticulous bacteriologic techniques used.

Acute mastoiditis. Influence of antibiotic treatment on the bacterial spectrum

The work was undertaken to investigate the spectrum of bacteria responsible for acute mastoiditis and to find out whether it is affected by intake of antibiotics prior to surgical treatment. The records were reviewed of 22 children with acute mastoiditis in whom mastoidectomy had been performed and bacterial cultures obtained. Eleven of the patients had had antibiotic treatment prior to admission (9 penicillin V and 2 erythromycin). Streptococcus pneumoniae was found in 8 of the purulent discharges: Haemophilus influenzae, Streptococcus beta-hemolyticus and Staphylococcus aureus in 2 each; Proteus mirabilis, Pseudomonas pyocyaneus and a Bacteroides strain in 1 each, while five discharges-all from patients pretreated with antibiotics-yielded no growth. None of the 9 patients pretreated with penicillin V provided pure cultures of pneumococci or beta-hemolytic streptococci, while one or the other of these species was found in 8 of the 11 untreated patients. Gram-negative bacteria were found both among those with and those without antibiotic pretreatment. The data indicate that pneumococci and beta-hemolytic streptococci are more likely to cause mastoiditis than are the other pathogens found in acute otitis media, and that, when drained at operation, purulent discharges are often found to have been sterilized by the pre-operative antibiotic treatment.

A microbiological study of secretory otitis media using an anaerobic technique

A serious anaerobic sampling and cultivation technique was used in order to obtain representative samples from 45 middle ear effusions in 30 patients with longstanding secretory otitis media (SOM). Despite the fact that an accurate sterilizing procedure was performed, 16% disclosed contaminated samples from the ear canal and tympanic membrane. Among the remaining samples, middle ear bacteria were found in 30% of which Staphylococcus epidermidis and Haemophilus influenzae contributed to the major part. Anaerobes were only occasionally found. The amount of bacteria found was sparse in all cases. It can be concluded that the inflammatory process in SOM is not maintained by anaerobic bacteria within the middle ear cavity.

Otitis media of infancy and early childhood. A double-blind study of four treatment regimens

A double-blind, randomized trial of four antimicrobial regimens was conducted in 383 infants and children with acute otitis media. The drugs used were penicillin V, amoxicillin trihydrate, erythromycin estolate, and erythromycin estolate with trisulfapyrimidines. Aspiration of middle ear fluid for culture was done before treatment and repeated during treatment if fluid persisted. Etiologic bacteria were most commonly pneumococci (31%) or Haemophilus sp (22%), and an additional 5% of patients had both organisms. Amoxicillin was the most effective in promoting initial response in pneumococcal infection. For Haemophilus infections, the cure rates with amoxicillin and the erythromycin-trisulfapyrimidines mixture were significantly better than with the other two regimens, and serous otitis did not occur during the follow-up period; however, new episodes of otitis were comparable in the four groups. Amoxicillin and the erythromycin estolate-trisulfapyrimidines combination appear to be somewhat more effective than penicillin V or erythromycin estolate.