Epidemiology and risk factors for extension of necrotizing otitis externa.

PURPOSE: Necrotizing otitis externa (OEN) is an aggressive and morbid infection of the external acoustic meatus. What are the risk factors for OEN extension? METHODS: French monocentric retrospective study (2004-2021), including patients with OEN defined by the association of an inflamed EAM, a positive nuclear imaging, the presence of a bacteriological sample and the failure of a well-followed local and/or general antibiotic treatment. OEN was extensive if it was associated with vascular or neurological deficits, if nuclear imaging fixation and/or bone lysis extended beyond the tympanic bone. RESULTS: Our population (n = 39) was male (74%), type 2 diabetic (72%), aged 75.2 years and pseudomonas aeruginosa was found in 88% of cases. Complications for 43% of patients were extensive fixation on nuclear imaging, for 21% of them the presence of extensive bone lysis, for 13% the appearance of facial palsy, for 5.3% the presence hypoglossal nerve palsy and for 2.5% the presence of thrombophlebitis or other nerves palsies. 59% of our population had extensive OEN. The diagnosis of the extensive OEN was made 22 days later (p = 0.04). The clinical presentation was falsely reassuring due to easier identification of the tympanic membrane (70% vs 46%, p = 0.17) but associated with periauricular oedema (42% vs 0%), bone exposure (16% vs 0%) and a temporomandibular joint pain (41% vs 12%). CONCLUSION: Delayed treatment of OEN, identification of clinical bone lysis, especially when the tympanic membrane is easily visualized, and the presence of unbalanced diabetes are potential risk factors for extension of OEN.

Managing emergency department patients with otalgia.

Though the vast majority of conditions associated with otalgia are not life-threatening, there are nuances and controversies in the diagnosis and management of even the most common diseases, such as acute otitis media and otitis externa. For more severe disease processes, such as necrotizing otitis externa, acute mastoiditis, and perichondritis, early recognition and timely management are paramount in reducing morbidity and mortality. A systematic approach to the evaluation of these patients is key to establishing an accurate diagnosis, identifying patients who are at high risk for dangerous etiologies or complications, and providing optimal patient care. This issue summarizes the most recent guidelines and presents a systematic, evidence-based approach to the emergency department evaluation and management of patients with otalgia.

Chronic otorrhea and osteomyelitis of the external auditory canal by Achromobacter xylosoxidans: an uncommon diagnosis.

PURPOSE: Achromobacter xylosoxidans is an emerging pathogen mainly associated with resistant nosocomial infections. This bacteria had been isolated in the ear together with other pathogens in cultures from patients with chronic otitis media, but it had never been reported as a cause of osteomyelitis of the external auditory canal. CASE PRESENTATION: We present a unique case of a healthy 81-year-old woman who presented with left chronic otorrhea refractory to topical and oral antibiotic treatment. Otomicroscopy revealed an erythematous and exudative external auditory canal (EAC) with scant otorrhea. The tympanic membrane was intact, but an area of bone remodeling with a small cavity anterior and inferior to the bony tympanic frame was observed. Otic culture isolated multi-drug-resistant A. xylosoxidans, only sensitive to meropenem and cotrimoxazole. Temporal bone computed tomography showed an excavation of the floor of the EAC compatible with osteomyelitis. Targeted antibiotherapy for 12 weeks was conducted, with subsequent resolution of symptoms and no progression of the bone erosion. CONCLUSIONS: Atypical pathogens such as A. xylosoxidans can be the cause of chronic otitis externa. Early diagnosis and specific antibiotherapy can prevent the development of further complications, such as osteomyelitis. In these cases, otic cultures play an essential role to identify the causal germ. This is the first case of EAC osteomyelitis due to A. xylosoxidans reported to date.

Diagnostic accuracy of eosinophil-to-lymphocyte ratio and eosinophil-to-neutrophil ratio as biomarkers for differentiating between fungal and bacterial infection in necrotising otitis externa.

INTRODUCTION: Necrotizing otitis externa (NOE) is a serious, progressive, and potentially life-threatening infection of the external auditory canal, affecting soft tissue and bone. The most common organism causing NOE is Pseudomonas Aeruginosa and less common are Fungal infections. When managing a patient with NOE, a culture is taken from the EAC in order to tailor the appropriate antimicrobial treatment, however commonly, the culture is sterile. Inflammation biomarkers may be used as adjuncts to inform on the differential diagnosis and as prognostic markers. AIM: To characterize and compare values and ratios of components of the complete blood count (CBC) at admission, at patients with positive swab culture. METHODS: A retrospective study of NOE patients was conducted. We included all patients admitted between the years 2001-2023, for whom a culture swab tested positive. We compared CBC findings at hospitalization between bacteria and fungi-positive culture patients. RESULTS: Eosinophils-to-Neutrophils Ratio (ENR) was significantly lower in the fungal group compared to the bacterial group 0.023 ± 0.02 and 0.04 ± 0.03, respectively (p-value = 0.025). Eosinophils-to-Leukocyte Ratio (ELR) was significantly lower in the fungal group compared to the bacterial group 0.058 ± 0.04 and 0.12 ± 0.1 respectively (p-value = 0.009). For definition of ELR ≤ 0.1 we found that, sensitivity was 88% (95%CI = 0.679-0.979) and NPV 90% (95%CI = 0.709-0.982). For definition of ENR ≤ 0.03 sensitivity was 88% (95%CI = 0.679-0.979) and NPV 88% (95%CI = 0.679-0.979). CONCLUSION: Lower values of ELR and ENR in patients with NOE are associated with fungal infection and can serve as a tool in adjusting an appropriate antimicrobial therapy in cases of sterile or when no culture is available.

Necrotizing external otitis: diagnostic clues in the emergency department.

PURPOSE: The assessment of necrotizing external otitis requires a high index of suspicion by the attending physician. The purpose of the study is to determine the accuracy of parameters available at the Emergency Department for the diagnosis of this pathology. METHODS: Retrospective diagnostic accuracy study. Patients consulting at the Emergency Department for longstanding ear swelling, severe otalgia, and failure to respond to topical treatment were included. Otoscopy, physical examination, CT appearance, and analytical results were tested for the diagnosis of necrotizing external otitis, using nuclear imaging as gold standard. Sensitivity, specificity, likelihood ratios and ROC curves were calculated. RESULTS: 24 patients were included; 13 cases were necrotizing external otitis, and 11 cases were other external ear pathologies. Erythrocyte sedimentation rate and C-reactive protein levels were significantly associated with necrotizing external otitis (AUC 0.92 p < 0.001, and 0.8 p < 0.001). Positive likelihood ratios were 10.15 for values of erythrocyte sedimentation rate over 26 mm/h, and 8.25 for C-reactive protein levels over 10 mg/L. Negative likelihood ratios were 0.08 and 0.28, respectively. These results were significant. The rest of clinical and radiological parameters were less accurate. CONCLUSIONS: Erythrocyte sedimentation rate and C-reactive protein are useful parameters in the evaluation of a case of longstanding otitis with clinical suspicion of necrotizing external otitis. If any of them is elevated, the probability of suffering this condition is significantly increased. If they are within normal ranges, an alternative diagnosis should be sought.

Auritidibacter ignavus, an Emerging Pathogen Associated with Chronic Ear Infections.

We describe detection of the previously rarely reported gram-positive bacterium Auritidibacter ignavus in 3 cases of chronic ear infections in Germany. In all 3 cases, the patients had refractory otorrhea. Although their additional symptoms varied, all patients had an ear canal stenosis and A. ignavus detected in microbiologic swab specimens. A correct identification of A. ignavus in the clinical microbiology laboratory is hampered by the inability to identify it by using matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Also, the bacterium might easily be overlooked because of its morphologic similarity to bacterial species of the resident skin flora. We conclude that a high index of suspicion is warranted to identify A. ignavus and that it should be particularly considered in patients with chronic external otitis who do not respond clinically to quinolone ear drop therapy.

Case Report: The application of metagenomic next generation sequencing in diagnosing fungal malignant external otitis: a report of two cases.

Background: Most of malignant external otitis (MEO) cases reported in the literature are attributed to Pseudomonas aeruginosa. Fungal infections in MEO are also likely but extremely rare. And conventional microbiology tests is difficult to diagnose. Case description: Two patients were diagnosed with Fungal malignant external otitis (FMEO) due to Aspergillus by metagenomic Next-Generation Sequencing (mNGS) and recovered after comprehensive treatment including operation and voriconazole. The antifungal treatment was delayed due to repeated cultures of secretions being negative and pathological examination showed granulation tissue proliferation with extensive neutrophil infiltration. Conclusion: mNGS might be helpful for patients suspected with FMEO, especially when conventional microbiology tests were negative.

[Efficacy and safety of topical combination therapy in patients with acute otitis externa].

AIM: To study the structure of the microbial landscape in patients with acute otitis externa, as well as to evaluate the efficacy and safety of the combined drug chloramphenicol/clotrimazole/beclomethasone/lidocaine (Candibiotic) as an empirical therapy of this disease. MATERIALS AND METHODS: In this retrospective study of real clinical practice, outpatient records of 963 patients who applied to the KDO of the Sverzhevsky Research Clinical Institute of Otorhinolaryngology with symptoms of otitis externa in the period from 2017 to 2022 were selected. Additional analysis was carried out on the clinical records of patients who received the combined drug Candibiotic. The endpoints of this analysis included data on the clinical and microbiological efficacy of therapy, as well as safety information. RESULTS: According to microbiological testing, 60.6% of microorganisms belonged to bacterial flora, 26% were bacterial-fungal associations, 11.6% were monofungal flora, in 1.8% of cases there was no growth of microorganisms. The most frequently isolated microorganisms were: Pseudomonas spp (n=291; 29.16%), Staphylococcus spp. (n=214; 21.4%), Candida spp. (n=194; 19.4%), Aspergillus spp. (n=133; 13.3%). Most of the patients (71.0%) received Candibiotic. In 69.7% of patients, the resolution of the clinical symptoms of otitis externa occurred within 7 days of therapy with Candibiotic. Complete eradication of microorganisms occurred in 87% of cases. Adverse events were recorded only in 3 (0.04%) cases. CONCLUSION: The study demonstrated an extremely high level of clinical efficacy and safety of therapy in patients with acute external infectious otitis who received the Candibiotic, which can be used as an initial empirical therapy in patients with otitis externa.

[Research progress of necrotizing otitis externa].

Necrotizing otitis externa is a progressive infectious disease involving the external auditory canal and even the skull base, which can lead to serious complications and even death if not treated in time. In this paper, the latest advances in etiology, pathogenesis, clinical manifestations, diagnosis and treatment were reviewed based on previous literature, providing reference for clinical diagnosis, treatment and future research.

Fungal Infections of the External Auditory Canal and Emerging Pathogens.

Fungal infections of the external auditory canal can range from common (otomycosis) to life threatening (necrotizing otitis externa). Proper identification of fungal pathogens is necessary to guide appropriate therapy, and a high index of suspicion for fungal causes of ear canal disease is critical. Fungal pathogens may be an especially important cause of ear canal disease in certain populations, including patients with diabetes, patients recently treated with antibiotics, and immunosuppressed patients. Opportunistic fungal infections of the ear canal are an emerging concern.

[Current diagnosis and treatment of skull base osteomyelitis].

Skull base osteomyelitis is a rare, refractory, and potentially fatal disease primarily caused by otogenic and sino rhinogenic infections. At times, it can mimic neoplasia complicating the diagnosis. With the use of antibiotics, advancements in diagnostic methods, and skull base surgical techniques, the mortality rate has significantly improved. However, the successful diagnosis and treatment of the disease is still challenging due to delayed diagnosis, lengthy treatment course, a tendency for relapse and lack of guidelines. Therefore, this article aims to review the progress in the diagnosis and treatment of skull base osteomyelitis.

Neoplasms of the Ear Canal.

Primary EAC neoplasms include benign and malignant lesions of bony, glandular or cutaneous origin. Small, benign slow growing bony neoplasms are often asymptomatic, diagnosed incidentally and might not require intervention. Both malignant and benign neoplasms of cutaneous and glandular origin can present with symptoms of chronic otitis externa, leading to delays in diagnosis. Prompt biopsy of soft tissue lesions associated with non-resolving otitis externa are warranted. Local and regional imaging is helpful to understand disease extent and origin, but even early-stage malignant neoplasms require aggressive surgical treatment.

Managing recurrent otitis externa in dogs: what have we learned and what can we do better?

Recurrent otitis externa is a common problem in dogs. Topical treatment for each flare is successful in the short term, but repeated cycles of inflammation and infection lead to chronic inflammatory changes, pain and aversion, and antimicrobial resistance. These make the flares more frequent and harder to control. Eventually, the changes become irreversible and require a total ear canal ablation/lateral bulla osteotomy or ablative laser surgery. Most ear canal surgery is avoidable if recurrent otitis is properly managed at an earlier stage. This requires a different mindset and approach to these cases, taking advantage of recent research and clinical findings. Most importantly, clinicians must appreciate that all recurrent ear infections in dogs are secondary. To achieve a good long-term outcome, it is essential that all the underlying factors in each case are diagnosed and managed using the primary, secondary, predisposing, and perpetuating framework. This means that the primary condition must be diagnosed and managed, the secondary infection treated, predisposing risks identified and corrected, and the perpetuating factors reversed. Treatment is in 2 phases: induction to get the ears in remission and then long-term maintenance therapy to prevent relapses. Treatment should be appropriate to each dog but will typically involve ear cleaning, topical antimicrobial therapy, and topical or systemic glucocorticoids. Novel treatments for infection and inflammation will offer additional options in the future. Understanding the triggers for recurrent otitis in dogs will help clinicians plan effective management regimens that will make a huge difference to the quality of life of their patients and their owners.

UK consensus definitions for necrotising otitis externa: a Delphi study.

OBJECTIVE: To establish consensus definitions for necrotising otitis externa (NOE) to facilitate the diagnosis and exclusion of NOE in clinical practice and expedite future high-quality study of this neglected condition. DESIGN: The work comprised of a systematic review of the literature, five iterative rounds of consultation via a Delphi process and open discussion within the collaborative. An expert panel analysed the results to produce the final outputs which were shared with and endorsed by national specialty bodies. SETTING: Secondary care in the UK. PARTICIPANTS: UK clinical specialists practising in infection, ear nose and throat (ENT) surgery or radiology. MAIN OUTCOME MEASURES: Definitions and statements meeting the following criteria were accepted: (a) minimum of 70% of respondents in agreement or strong agreement with a definition/statement AND (b) <15% of respondents in disagreement or strong disagreement with a definition/statement. RESULTS: Seventy-four UK clinicians specialising in ENT, Infection and Radiology with a special interest in NOE took part in the work which was undertaken between 2019 and 2021. The minimum response rate for a Round was 76%. Consensus criteria for all proposed case definitions, outcome definitions and consensus statements were met in the fifth round. CONCLUSIONS: This work distills the clinical opinion of a large group of multidisciplinary specialists from across the UK to create practical definitions and statements to support clinical practice and research for NOE. This is the first step in an iterative process. Further work will seek to validate and test these definitions and inform their evolution.

Acute Otitis Externa: Rapid Evidence Review.

Acute otitis externa is an inflammatory condition that affects the external ear canal. It is usually of rapid onset and is generally caused by bacterial infection. The primary bacterial infections are Pseudomonas aeruginosa and Staphylococcus aureus. Acute otitis externa presents with pain (otalgia), redness, and swelling of the canal. It is more common in children and young adults. Tenderness on movement of the pinna or tragus is the classic finding. Analgesics and topical antibiotics are the mainstays of therapy. Topical medications include acetic acid 2%, aminoglycosides, polymyxin B, and quinolones with and without corticosteroids. There is no evidence that any one preparation is clinically superior to another, and the choice of treatment is based on factors such as cost, whether the tympanic membrane is intact, and patient adherence. Oral antibiotics are indicated only if evidence of cellulitis occurs outside of the ear canal or if associated conditions such as immunocompromise, diabetes mellitus, or conditions that would not allow for the use of topical treatment are found. Duration of topical treatment is usually seven to 10 days. Keys to prevention include avoiding injury to the ear canal and keeping it free of water.

Systematic review of the diagnosis and management of necrotising otitis externa: Highlighting the need for high-quality research.

OBJECTIVES: To present a systematic review and critical analysis of clinical studies for necrotising otitis externa (NOE), with the aim of informing best practice for diagnosis and management. DESIGN: Medline, Embase, Cochrane Library and Web of Science were searched from database inception until 30 April 2021 for all clinical articles on NOE. The review was registered on PROSPERO (ID: CRD42020128957) and conducted in accordance with PRISMA guidelines. RESULTS: Seventy articles, including 2274 patients were included in the final synthesis. Seventy-three percent were retrospective case series; the remainder were of low methodological quality. Case definitions varied widely. Median patient age was 69.2 years; 68% were male, 84% had diabetes and 10% had no reported immunosuppressive risk factor. Otalgia was almost universal (96%), with granulation (69%) and oedema (76%) the commonest signs reported. Pseudomonas aeruginosa was isolated in 62%, but a range of bacterial and fungal pathogens were reported and 14% grew no organism. Optimal imaging modality for diagnosis or follow-up was unclear. Median antimicrobial therapy duration was 7.2 weeks, with no definitive evidence for optimal regimens. Twenty-one percent had surgery with widely variable timing, indication, or procedure. One-year disease-specific mortality was 2%; treatment failure and relapse rates were 22% and 7%, respectively. CONCLUSION: There is a lack of robust, high-quality data to support best practice for diagnosis and management for this neglected condition. A minimum set of reporting requirements is proposed for future studies. A consensus case definition is urgently needed to facilitate high-quality research.

Immunosuppression, infection, and epidermal compromise: an aetiological triad for necrotising otitis externa that highlights potential modifiable risk factors.

OBJECTIVE: A key clinical feature of necrotising otitis externa is granulation tissue arising from the ear canal, representing epidermal compromise. The aim of this work was to explore the role of epidermal compromise in the aetiology of necrotising otitis externa. METHOD: A structured risk factor history was taken from 54 patients diagnosed with necrotising otitis externa between 2017 and 2022. Primary care records were also reviewed. RESULTS: A total of 94 per cent of patients reported incidents of potential epidermal compromise preceding severe pain onset, including a 35 per cent incidence of ear syringing. A total of 94 per cent of patients were immunosuppressed, including 78 per cent with diabetes. All patients had medical co-morbidities. CONCLUSION: This study proposed an aetiological triad for necrotising otitis externa: immunosuppression, infection and epidermal compromise. Epidermal compromise is a potentially modifiable risk factor for necrotising otitis externa. Meticulous primary ear care for older adult, diabetic and immunosuppressed patients is recommended. These populations should never undergo ear syringing and should avoid ear canal trauma and prolonged exposure to moisture.

Management and long-term comorbidities of patients with necrotizing otitis externa.

PURPOSE: We aimed to present the management of the patients with necrotizing otitis externa (NOE) and its comorbidities in early and long-term follow-up. METHODS: Between 2011 and 2022, 30 patients with the diagnose of NEO, who had cortical bone erosion or trabecular demineralization in temporal bone computed tomography and administered at least 6-week antimicrobial therapy were included in the study. Clinical, laboratory and imaging findings of patients, and comorbidities during follow-up were analysed. NOE extending further from the petro-occipital fissure on magnetic resonance imaging was accepted as medial skull base (MSB) involvement. RESULTS: 30 patients, (8 women, 22 men, mean age 66.2 ± 1.7), with NOE were followed 36.4 ± 29.6 months. The mortality rate was 23.33% and the mean survival time was 12.37 ± 11.35 months. Repeated cultures reveal a new or second pathogen in 5 patients (20%). Severe and profound sensorineural hearing loss (SNHL) were observed in 4 and 12 patients, respectively. Labyrinthitis ossificans emerged in 3 of 6 surviving patients with profound SNHL during follow-up. Chronic disease anemia (CDA) (66.66%), cerebrovascular disease (CVD) (43.33%), chronic renal failure (CRF) (30%), and retinopathy (26.66%) were the most frequent comorbidities in patients with NOE. Cranial nerve paralysis (CNP) (P < 0.001), SNHL (P < 0.04), CDA (P < 0.005), and mortality (P < 0.022) were significantly associated with the presence of MSB involvement. CONCLUSIONS: NOE is a disease that requires long-term follow-up, causes severe morbidity, and has a high mortality rate. MSB involvement is associated with CNP, SNHL and labyrinthitis ossificans. Moreover, CDA, CVD, CRF and retinopathy are the most common comorbitidies needed to be managed.

Otitis externa caused by Malassezia slooffiae complicated with mastoiditis: A case report.

Herein, we report a case of otitis externa caused by Malassezia slooffiae complicated with mastoiditis. A 70-year-old male complained of fever and severe otorrhea from left external auditory canal 2 months after undergoing a craniotomy to remove a hematoma. He had right-sided paralysis and undertook bed rest. Brain computed tomography revealed continuous fluid accumulation in the left mastoid air cells and middle ear from left external auditory canal in addition to leukocytosis and increased C-reactive protein level. The tympanic membrane was severely swelling. These results indicated the presence of otitis media and mastoiditis. Otorrhea culture showed large amounts of M. slooffiae. The administration of liposomal amphotericin B (L-AMB), the irrigation of external auditory canal with normal saline, and the application of topical ketoconazole ointment were started. The administration of L-AMB for 8 weeks and voriconazole, which was switched from L-AMB, for 4 weeks ameliorated his infection and he was transferred to another hospital to receive rehabilitation. From these results and his clinical course, the diagnosis of otitis externa caused by Malassezia slooffiae complicated with mastoiditis was made. And the possibility of the contamination by M. slooffiae was very low. Clinicians should be aware that M.slooffiae can provoke otological infections since M. slooffiae is the most common Malassezia sp. in external auditory canal.