Epigenetic Regulation as a New Therapeutic Target for Middle Ear Cholesteatoma.

HYPOTHESIS: To evaluate the effectiveness of the menin-MLL inhibitor, MI503, as a conservative treatment of middle ear cholesteatoma (cholesteatoma) in a mouse model and to confirm its safety profile regarding auditory function in vivo. BACKGROUND: Cholesteatoma is a mass formed by the keratinizing squamous epithelium in the tympanic cavity and/or mastoid and subepithelial connective tissue and by the progressive accumulation of keratin debris with/without a surrounding inflammatory reaction. Although the main treatment is surgical therapy, the techniques to prevent recurrence remain a critical area of research. Recently, the use of MI503 in experiments resulted in the inhibition of the growth of cholesteatoma in vivo under histone modification. METHODS: After cholesteatoma was induced in ICR mice (n = 7) by keratinocyte growth factor expression vector transfection, MI503 (50 µM) or phosphate-buffered saline was topically injected for 14 days. The effects of MI503 against cholesteatoma were analyzed by micro-computed tomography images. For the in vivo ototoxicity study, a single intratympanic injection of MI503 (50 or 500 µM) or phosphate-buffered saline (n = 4 each) was done in the ICR mice. An auditory brainstem response was performed at days 0, 1, and 14. For morphological analysis, immunostaining for Phalloidin/F-actin and Myo7a was performed. RESULTS: MI503 reduced keratinocyte growth factor-induced cholesteatoma in vivo (4 of 4 [100%]). No difference was found in the mean variation of the average of the auditory brainstem response thresholds between the three groups in the in vivo ototoxicity study, thus confirming its safety profile regarding auditory function. MI503 does not demonstrate any deleterious effects on murine hair cells when assessed by immunostaining. CONCLUSION: These findings demonstrate an encouraging safety profile for the use of menin-MLL inhibitor for the conservative treatment of cholesteatoma.

The Effect of Zbxz23ir-21 NANO(nanomaterials) Delivery Vector on Apoptosis and PTEN(phosphatase and tensin homolog deleted on chromosome ten)/PI3K(Intracellular phosphatidylinositol kinase)/AKT(related to the A and C kinase) in Children with CHOLESTEATOMA in Middle Ear.

Cholesteatoma of the middle ear is a kind of cystic disease with clear boundary formed by the abnormal growth of keratosquamous epithelium in temporal bone. Cholesteatoma otitis caused by it is a common disease in otorhinolaryngology. The EPR effect promotes the selective distribution of macromolecular substances in tumor tissues, which can increase drug efficacy. The purpose of this paper is to prepare and deliver the mir34a small molecule regulator, rubine, by nanotechnology, and to deliver it to the cells successfully. It can passively target tumor tissue through EPR effect, and play its regulatory role on miR-34a, thus inhibiting the growth of cholesteatoma cells. The effects of nano delivery on apoptosis and PIEN/P13K/AKt of children with middle ear choledochoma were tested in this paper. The experimental results were conducted on cholesteatoma cells as cell lines and balb/c nude mice as experimental objects. The expression of PTEN/PI3K/AKT in experimental group and control group was detected by immunohistochemistry. Apoptosis was discussed by cell activity detection. The physical and chemical properties, encapsulation efficiency, drug release ability in vitro and antitumor activity of nanoparticles in vitro and in vivo were studied. The results of cell level experiments in vitro showed that free RUBINE caused about 15% apoptosis, which was not different from RC NPs. The results showed that the nanoparticles could improve the expression of miR-34 in the cells, and then regulate the expression of Bcl-2, Cdk6 and CyclinD1, and play the inhibitory effect of miR-34a on the proliferation and migration of tumor cells.

Chemically Assisted Dissection With Sodium 2-Mercaptoethanesulfonate (MESNA) in the Surgical Management of Pediatric Cholesteatoma.

OBJECTIVE: To evaluate the effectiveness of the chemically assisted dissection with sodium 2-mercaptoethanesulfonate (MESNA), in the reduction of residual and recurrent cholesteatoma after mastoidectomy in children with chronic cholesteatomatous otitis media (CCOM). STUDY DESIGN: Retrospective case-control study. SETTING: Tertiary referral center. POPULATION: One hundred forty mastoidectomies performed in patients under 18 years of age for the treatment of CCOM. INTERVENTIONS: Chemically assisted dissection (CAD) with MESNA compared with surgical dissection without MESNA. MAIN OUTCOME MEASURES: Recidivism of cholesteatoma (recurrence and residual disease), variations in the average of bone conduction threshold after treatment, and complications. RESULTS: Recidivism of cholesteatoma was significantly lower when CAD with MESNA was used (p < 0.0001). No difference was found in the mean variation of the average of bone conduction thresholds between the groups, confirming its safety profile regarding auditory function. Meatoplasty stenosis after surgery was more prevalent within CAD with MESNA group (p: 0.049). CONCLUSION: Recurrent and residual cholesteatoma remains a problem, especially in children and despite surgical techniques such as canal wall down mastoidectomy and endoscopic ear surgery. CAD with MESNA can be safe and effective to reduce recurrence rates. Multicenter and prospective studies with larger number of patients are needed to validate these findings. The higher rate of meatoplasty stenosis after CAD with MESNA merits additional clinical research to confirm these findings, as well as in vitro studies evaluating the effect of the drug on the activity of fibroblasts and other growth factors that may be involved.

Efficacy of antibiotic prophylaxis prior to tympanoplasty for contaminated cholesteatoma.

OBJECTIVES: To evaluate the efficacy of combined antistaphylococcal and antipseudomonal preoperative antibiotics for preventing surgical site infections following tympanoplasty and mastoidectomy with contaminated cholesteatoma. STUDY DESIGN: Retrospective chart review. METHODS: Medical records of patients who underwent tympanoplasty ± mastoidectomy for cholesteatoma were reviewed. Only cases considered to have contaminated or dirty surgical fields were included. The primary outcome measure was occurrence of postoperative surgical site infections, perichondritis, pinna abscess, periotic cellulitis, or periotic abscess requiring systemic antibiotic therapy or surgical intervention. RESULTS: The charts of 326 patients who underwent tympanoplasty ± mastoidectomy were reviewed. Of those, 195 met inclusion criteria. Preoperative antibiotics included clindamycin and ceftazidime or gentamicin. Patients treated with no perioperative antibiotics had a surgical site infection rate of 11%, and those treated with perioperative antibiotics had a rate of 1% (P = 0.02). CONCLUSION: Administration of preoperative antibiotics to cover staphylococcal and pseudomonal species may prevent surgical site infections with tympanoplasty ± mastoidectomy for contaminated cholesteatoma. LEVEL OF EVIDENCE: 4. Laryngoscope, 126:2363-2366, 2016.

[Infection of chronic otitis media with Acinetobacter：6 cases report].

Objective:To investigate the clinical characteristics, diagnostic methods and prognosis of patients with chronic otitis media with Acinetobacter infection. Method:Retrospective analysis of clinical data of 6 cases of chronic otitis media complicated with Acinetobacter infection. Including history, clinical manifestations, laboratory examination, audiology, inner ear, CT, MRI imaging characteristics, treatment and prognosis of etc. to summarize the clinical characteristics, diagnosis and treatment of chronic otitis media with Acinetobacter infection. Result:The age was between 17 years old and 61 years old (Median age 30 years) .Two of them was male and 4 were female. Four cases were had underlying diseases. Five cases with main symptom of cholesteatoma, 1 case with earache symptoms, and 1 case with facial paralysis symptoms. Four cases had vary degrees of physical decline and destruction of bone. After surgery treatment, five patients improved ear pus, among 3 cases was cured, 2 cases of recurrence. Conclusion:Chronic otitis media with Acinetobacter infection occurs in the patient with elderly, poor physical constitution. However, the recurrence rate of conventional treatment is higher. The disease has high misdiagnosis rate. Operation combined with sensitive antibiotic therapy is a radical cure method.

Immunotargeted photodynamic therapy for cholesteatoma: in vitro results with anti-EGFR-coated indocyanine green nanocapsules.

HYPOTHESIS: The objective was to test the hypothesis that immunotargeted photodynamic therapy (IT-PDT) using anti-epithelial growth factor receptor (EGFR)-coated indocyanine green (ICG) nanocapsules would selectively kill cholesteatoma-derived keratinocytes while sparing middle ear-derived mucosa cells in vitro. BACKGROUND: Rates of residual cholesteatoma caused by incomplete microsurgical removal are unacceptably high; thus, development of an adjuvant therapy to safely destroy undetected residual cholesteatoma cells would be desirable. IT-PDT is a possible means to achieve this end. METHODS: ICG nanocapsules coated with anti-EGFR were synthesized and applied to cholesteatoma-derived keratinocytes and middle ear mucosa cells in vitro. Selective binding to keratinocytes was evaluated by fluorescence microscopy. Activation of ICG was undertaken by applying near-infrared light (810 nm) at an applied energy dose of 1,080 J/cm. Cell death was evaluated 2 hours after treatment with trypan blue staining. RESULTS: Selective and robust nanocapsule binding to keratinocytes, but not mucosa cells, was confirmed by preapplication and postapplication fluorescence measurements. A keratinocyte cell death rate of 70.12% ± 2.50% was achieved, whereas negligible mucosa cell death was observed. Negligible cell death was also observed for both cell types with application of the nanocapsules alone or with application of near-infrared light alone. CONCLUSION: Anti-EGFR ICG nanocapsules applied topically and activated as part of an IT-PDT scheme results in a high rate of cholesteatoma-derived keratinocyte cell death while negligibly affecting middle ear mucosal cells in vitro. These preliminary findings suggest that this is a feasible concept and that further investigation is warranted.

Cochlear effects of intraoperative use of Mesna in cholesteatoma surgery.

BACKGROUND AND AIM OF THE WORK: Mesna is thiol compound proposed as chemical dissector in otolaryngologic surgery. The aim of this study was to address the issue of possible ototoxicity from topical administration of MESNA into the middle ear during otologic surgery. METHODS: Audiological findings of patients (n=55) who underwent canal wall up tympanomastoidectomy with the ancillary use of Mesna in 1-year period were retrospectively reviewed. We identified another set of 51 patients who had undergone otologic surgery without the use of Mesna to serve as a control group. Preoperative and postoperative mean bone conduction thresholds were calculated and compared between the two groups for the frequencies of 500,1000,2000, and 3000; 4000 and 8000 Hz were further analyzed to search for high-frequency sensorineural hearing loss. RESULTS: Fifty-five patients were operated on with the ancillary use of Mesna and 51 underwent surgery with traditional mechanical dissection alone. When mean preoperative bone conduction values were compared with postoperative values, no significant differences were found for any of the frequencies tested in both groups. Analyzing changes in bone conduction at 4000 and 8000 Hz a slight worsening was observed in both groups. CONCLUSIONS: We found no difference in hearing thresholds between the treatment and control groups. Thus, the results of this study confirmed data obtained in laboratory animal models demonstrating that intraoperative use of Mesna in middle ear surgery is safe and does not lead to ototoxic effects.

Dilute vinegar therapy for the management of spontaneous external auditory canal cholesteatoma.

The purpose of this study is to evaluate the efficiency of conservative dilute vinegar therapy in the management of spontaneous external auditory canal cholesteatoma (EACC). From 2000 to 2007, 19 patients presented to our clinic with spontaneous EACC. EACC was divided into four grades based on the temporal bone computed tomography: grade I with flattening of bony external canal, grade II with partial destruction of inferior bony canal, grade III with total destruction of inferior bony canal and grade IV with bony destruction into the middle ear and mastoid cavity. Clinical findings and treatment results were recorded. Microscopic local cleansing and dilute vinegar therapy was conducted in the ears with grades I, II and III. Combined mastoid surgery and dilute vinegar therapy was conducted in four ears with stage IV. There were no recurrences after average of 31 months follow-up. Spontaneous EACC can be effectively controlled with dilute vinegar therapy after microscopic local cleansing. However, surgery must be considered in the cases which have involved the mastoid and middle ear. Dilute vinegar therapy in combination with microscopic local cleansing was effective in the management of spontaneous EACC. Dilute vinegar therapy is an easy, cost-effective, and home-based cleansing method to prevent EACC and promotes healing. However, long-term follow-up may reveal frequent recurrence of cholesteatoma debris and involvement of middle ear or mastoid cavity, and then meticulous debridement with skin graft or surgical intervention should be considered.

Microbiological profile with antibiotic sensitivity pattern of cholesteatomatous chronic suppurative otitis media among children.

INTRODUCTION: Chronic suppurative otitis media (CSOM) is the most common cause of childhood hearing impairment in the developing countries and atticoantral type is associated with increased incidence of intracranial and extracranial complications. This study was undertaken to define the microbiology of atticoantral type of chronic otitis media and the antibiotic sensitivity pattern, thereby reducing the potential risks of complications. MATERIALS AND METHODS: A retrospective study was done in the Department of Otolaryngology, JIPMER, Puducherry from the year August 2003 to October 2009 using the medical record department database to retrieve the patient details. During this study period, 223 children with atticoantral type CSOM consisting of 126 males and 97 females with an age range of 1-14 years were assessed. Patients with persistent otorrhea for more than 3 months with atticoantral type of chronic otitis media were selected. The exudates were collected under sterile conditions and inoculated onto culture media; bacterial growth and antibiotic sensitivity pattern were studied. RESULTS: Nine species of micro organisms were isolated from the middle ear aspirate, Pseudomonas aeruginosa being the most predominant isolate constituting about 32% (72 discharging ears) of the total isolates followed by Proteus mirabilis (20% of isolates) and Staphylococcus aureus (19% of isolates). Gram negative organisms accounted 58% of total isolates and gram positive organisms constituted 22% isolates. Candida albicans and methicillin resistant S. aureus were identified in 4% and 2% of isolates, respectively. 100% of Pseudomonas isolates showed susceptibility to ceftazidime and a high sensitivity (92% of isolates) to ciprofloxacin and 88% isolates were sensitive to amikacin. 100% of P. mirabilis isolated from inoculates showed sensitivity to ceftazidime and ciprofloxacin. It also showed 87-97% sensitivity to ceftriaxone, amikacin and ampicillin. All (100%) of the Staphylococcus isolates were sensitive to vancomycin and 84-86% were sensitive to ciprofloxacin and erythromycin. In general, gram negative organisms showed increased sensitivity to ceftazidime, ciprofloxacin and amikacin, while gram positive organisms to vancomycin, erythromycin and ciprofoxacin. CONCLUSION: Continuous and periodic evaluation of microbiological pattern and antibiotic sensitivity of cholesteatomatous CSOM is necessary to decrease the potential risks of complications by early institution of appropriate systemic and topical antibiotic alongside mastoid exploration. We believe that our data may contribute to an effective medical management of chronic suppurative otitis media with cholesteatoma. Since the most common organisms in our clinical set up being P. aeruginosa, P. mirabilis and S. aureus, which showed a percentage susceptibility of 100% to ceftazidime and vancomycin, thus making it an empirical antibiotic combination therapy of choice in the recent times.

Notes on the microbiology of cholesteatoma: clinical findings and treatment.

Anomalous proliferation of the cholesteatoma epithelium is caused by extrinsic factors such as toxins or bacterial antigens combined with lytic enzymes, lymphokines and cytokines released from the inflammatory infiltrate. This could explain the close relationship between the aggressiveness of cholesteatoma and repeated bacterial superinfection, therefore it is very important to know the bacteria involved in order to control the regrowth of skin following surgery, reduce the aggressive potential of the cholesteatoma and limit the incidence of complications. This study focused on 70 females and 80 males aged between 15 and 65 years, affected by cholesteatomatous otitis media; all underwent bacteriological examination of the auricular secretion. The floral bacteria which proved to play the most important role (60.3%) were the aerobic type and the highest levels were those of Pseudomonas aeruginosa (31.1%) followed by Staphylococcus aureus (19.1%), Proteus mirabilis (7.7%), Escherichia coli (1.4%) and Klebsiella pneumoniae (1%). Anaerobic floral bacteria were found in a fairly high percentage of cases (38.2%); in particular, anaerobic gram-positive cocci (Peptococcus 12.4% and Peptostreptococcus in 4.8% of cases), Bacteroides (12.4%), Clostridium (3.8%), Fusobacterium (2.9%) and Propionobacterium (1.9%) were isolated. In 3 cases of mycetes (1.4%) only Aspergillus, in association with Pseudomonas and Staphylococcus, was identified. The study showed, then, how effective second generation fluoroquinolones and third generation cephalosporins are (the latter being used in pre-adolescent children), the reason being that these antibiotics work not only on Pseudomonas and Staphylococcus, but also on the anaerobic bacteria.

Topical application of 5-fluorouracil on attic cholesteatoma results in downregulation of keratinocyte growth factor and reduction of proliferative activity.

To investigate the cell-biological effect of topically applied 5-fluorouracil (5-FU) on middle ear cholesteatoma, 12 attic cholesteatomas were treated with topical application of 5-FU cream, two to five times with an interval of 2 weeks (5-FU group). The control group comprised 65 cholesteatoma that were not treated with 5-FU. All lesions were later excised surgically and processed for immunohistochemical analyses of Ki-67, keratinocyte growth factor (KGF) and its receptor (KGFR). 5-FU significantly reduced the expression of KGF, did not change KGFR expression, and significantly reduced the Ki-67 labeling index, relative to the control group. The effect of 5-FU on cholesteatoma seems to be mediated, at least in part, through downregulation of KGF in stromal cells and reduction of the proliferative activity of epithelial cells.

[Posterior cranial fossa abscess secondary to cholesteatoma]. / Cholestéatome compliqué d'abcès de la fosse postérieure.

OBJECTIVE: The intra cranial complications of chronic ear disease continue to pose a challenge in Senegal, despite advances in anti microbial therapy. Posterior cranial fossa abscesses are rare and continue to be associated with significant morbidity and mortality rates. We describe the presentation and management of a large cerebellar abscess secondary to cholesteatoma. METHODS AND RESULTS: A 11-year-old female presented with an inflammed fluctuant swelling of the right temporal region with ipsilateral otorrhoea. Examination demonstrated an auto atticotomy, large marginal perforation of the tympanic membrane associated with polyp. A diagnosis of otomastoiditis secondary to cholesteatoma was made. The abscess of the right temporal region was incised and drained and the patient was commenced on broad spectrum antibiotics. However the patients clinical status did not improve and there was a deterioration in her neurological status. CT brain and temporal bones demonstrated a large abscess in the cerebellum. 30 CC of pus were drained through a posterior fossa burr hole by the neurosurgeons. A radical mastoidectomy for extensive cholesteatoma of the right ear was subsequently carried out when the patients condition improved. CONCLUSION: Cerebellar abscess is a life threathning condition. In the presence of complicated chronic ear disease, clinical suspicion must be high as early symptoms and signs may be misleading. A low threshold for the performance of brain imagining will aid early diagnosis and allow prompt definitive treatment.

[Acute Mastoiditis in Children: a series of 38 Cases]. / Les mastoïdites aiguës de l'enfant.

OBJECTIVE: We reviewed retrospectively the clinical, radiological and therapeutic findings in 38 infants and children with acute mastoiditis. MATERIAL AND METHODS: From 1988 to 2001, 38 children (mean age 36 months) were treated for acute mastoiditis and periostitis or retroauricular abscess. RESULTS: Diagnosis was usually made on the basis of typical retroauricular signs (60% of the cases), but was sometimes delayed owing to inappropriate antibiotics in 16 cases (42%) or atypical presentation in 3 (8%). Twenty-four children (70%) had no otolaryngological history. Pneumococci were isolated in most of the cases (n=15, 57%) with 13% having penicillin-resistant pneumococci. Lateral sinus thrombophlebitis was the most frequent complication, observed in 3 children (8%). Mastoiditis revealed congenital or acquired cholesteatoma in 4 children, who were all four infected with Gram-negative bacteria. Intravenous antibiotic therapy was associated with antroatticotomy in 36 children. CONCLUSION: Despite emergence of new antibiotic resistance, the annual rate of mastoiditis has remained unchanged, remaining a serious complication of middle ear acute otitis. Cholesteatoma should be suspected in case of Gram-negative bacteria or in older children.

Quantity of aerobic bacteria in the bony portion of the external auditory canal of children.

OBJECTIVE: the human external auditory canal (EAC) hosts a commensal bacterial flora of mainly non-pathogens, but bacterial pathogens may also be present. The latter are important in the aetiopathogenesis of external otitis and middle ear cholesteatoma with discharge. The purpose of this study was to quantify the bacteria normally harboured in the healthy EAC and on a well-defined region of the cavum conchae (CC) of children. METHODS: bacterial samples were collected from the CC and bony portion of the EAC of 32 children (18 boys, 14 girls; median age 5 years). Prior to sampling, the EACs were either left untreated, anaesthetized with Bonain's solution, or washed with 70% alcoholic solution. The samples were incubated at 37 degrees C and evaluated regarding bacterial species and number. RESULTS: the predominant bacterial non-pathogens were coagulase-negative Staphylococci and coryneforms (diphtheroids) and pathogens Staphylococcus aureus and Pseudomonas aeruginosa. Total bacterial counts of the CC ranged between 2 x 10(3) and 4.6 x 10(4) CFU/cm(2) (median value 7 x 10(3); n = 14). Total bacterial counts from the bony portion of the EAC ranged between 0 and 5.7 x 10(7) CFU/EAC (median value 8 x 10(3); n = 32). Pre-treatment of the EACs with Bonain's solution containing the highly bactericidal substance phenol or with 70% alcoholic solution did not sterilize the EAC. CONCLUSIONS: small numbers of bacterial non-pathogens (and sometimes pathogens) are found in the EAC of children. Neither phenol nor 70% alcoholic solution can inhibit or eradicate all these microorganisms.

[Antibiotic treatment in surgery for cholesteatoma]. / Tratamiento antibiótico en la cirugía del colesteatoma.

Cholesteatoma surgery is considered as a dirty one and consequently tributary of preoperative and postoperative antibiotic treatment. Thirty-seven patients diagnosed of cholesteatoma and surgically treated in 1994 are retrospectively analyzed in this article. All of them, whether or not presented with active preoperative otorrhea, received a protocolized antibiotic treatment with topical gentamicin and dexamethasone and oral clindamycin during seven postoperative days. The presence or absence of preoperative or postoperative infection, usually as suppuration is analyzed. Otopyorrhea occurred in 22 patients (62%) before surgery and only in 9 cases (25%) after surgery. Preoperative discharging ears showed greater disposition to continuing the suppuration. The surgical technique followed and the reconstructive middle ear procedure--with autologous bone or other synthetic materials (PORP, TORP)--have not proved, statistically, any predictably value regarding the appearance of any active postoperative infection. As a result of the study done, oral ciprofloxacin has been protocolized only in those adults showing a refractory suppuration to the antibiotic treatment employed. In patients with preoperative otorrhea, topical ciprofloxacin has been protocolized before surgery with the main aim to decrease the postoperative infections incidence of these cases.

[Clinical and bacteriology observation on intraoperation usage of tarivid otic solution in treatment of chronic otitis media with cholesteatoma].

OBJECTIVE: To determine the effect and safety of Tarivid (oflorxacin) otic solution used during the operation in treatment for chronic otitis media with cholesteatoma. METHOD: 42 patients were divided into two groups. In Tarivid group, 23 patients' operative cavities were soaked with 0.3% Tarivid, while other 19 patients' operative cavities in boric acid group were soaked with 4% boric acid during the open mastoidectomy with tympanoplasty. RESULT: The recovery rate was 82.6% and 50% respectively. There was significant difference between two groups (P < 0.05). No side effect was observed. CONCLUSION: It shows that using Tarivid otic solution in the operation can improve the outcome of the operation and has high security.

[Otogenic cerebral abscess: description of 3 cases, clinical and therapeutic considerations]. / Ascesso cerebrale otogeno: descrizione di tre casi, considerazioni cliniche e terapeutiche.

The authors use the 3 cases of otogenous cerebral abscess which came under observation as starting point for a discussion of the main etiopathogenetic, microbiological, clinical-diagnostic and therapeutic aspects of this disorder. After a brief presentation of the data regarding incidence, preferential localization and age of onset, they discuss the means for intracranial spread of infection and the related symptoms. As regards diagnosis, the authors assert that clinical examination and imaging techniques--CT and especially MRI--enable one to determine the dimension and site of the abscess cavity, differentiating it from other intracranial lesions and to monitor clinical evolution and response to therapy. After mentioning the principle bacteria involved in infection, they deal with the various means of treatment. The authors favor surgical removal of the auricular phlogistic focus and medical treatment of the intracranial abscess. They resort to neurosurgery only in those cases which do not respond to drug treatment or when the size and particular location of the abscess threaten the patient's life. In conclusion, the authors underline the problems seen today in diagnosis and therapy, comparing the quoad vitam and quoad valetudinem prognosis for the affected patients.

Role of anaerobic bacteria in chronic otitis media and cholesteatoma.

Otitis media (OM), a common infection in children, can cause significant morbidity. Selection of the most appropriate treatment regimen directed against the pathogens responsible for the OM can minimize complications. The most frequently isolated bacteria from chronic OM are Staphylococcus aureus, Pseudomonas aeruginosa and anaerobic bacteria. The predominant anaerobes are Peptostreptococcus spp., pigmented Prevotella and Porphyromonas spp., Bacteroides spp. and Fusobacterium spp. Many of the organisms causing OM can produce beta-lactamase, which can contribute to the failure of penicillins therapy. The appropriate surgical and medical therapy for chronic OM is reviewed.