(Scotland) Improving Outcomes of Necrotising Otitis Externa (IONOE)
Research type
Research Study
Full title
A Multicentre Prospective Study to Improve Outcomes of Necrotising Otitis Externa in the UK
IRAS ID
310016
Contact name
Susanne Hodgson
Contact email
Sponsor organisation
University of Oxford
Clinicaltrials.gov Identifier
Duration of Study in the UK
2 years, 9 months, 31 days
Research summary
Summary of Research
Necrotising Otitis Externa (NOE for short) is a severe ear infection that causes bad ear pain and hearing loss. Older people are particularly at risk of getting NOE, but it can also affect those with diabetes or a poor immune systems. There are no national or international guidelines for how to diagnose or treat NOE.
In this study, specialists working at a number of hospitals in the UK will keep detailed records of how they diagnose and treat NOE, and whether the treatment works. We will analyse this information to find out the risk factors for NOE, which scans and surgical samples are the best way to diagnose this disease, and which type and dose of antibiotics work best. Doctors currently do not know what is the best way to manage NOE, with different people trying different things – we hope that our analysis will formulate the optimal strategy for managing NOE and improve outcomes.
We are also interested to know more about the bacteria most commonly associated with this infection. We will be asking the question whether the specific bacteria that causes NOE has any characteristics that make it more likely to cause severe, invasive infection.
We will ask patients involved in this study to read an information booklet, sign a consent form and complete a ‘quality of life questionnaire’ at the beginning and end of the study. Patients won’t need to attend any special clinics or have any special tests, most of the information will be collected from their medical notes and scans.
We will publish our results in clinical and medical journals, to help with future clinical studies and guidelines on management NOE with particular benefit for the elderly.
Summary of Results
Necrotising Otitis Externa (NOE for short) is a severe ear infection that causes bad ear pain and hearing loss. Older people are particularly at risk of getting NOE, but it can also affect those with diabetes or a poor immune system. There are no national or international guidelines for how to diagnose or treat NOE and management is thought to vary across the UK. There is very limited research on this serious infection.The IONOE study is a UK based study that took place between 2021 and 2025, involved 23 sites in England, Scotland and Wales and enrolled 343 patients. The aim of the study was to identify risk factors for NOE, which scans and surgical samples are the best way to diagnose this infection, and which type and dose of antibiotics work best. Patients were invited to take place in the study if they had a scan of their head to investigate a clinical suspicion of NOE. Information on patients’ symptoms, test results, treatments received and outcome was then collected over follow-up for a year. The study was ‘observational.’ This means that all patients were treated according to the advice of local clinicians, with different doctors trying different things – the study did not tell clinicians what treatment to give the patients. The study team simply collected information from medical notes and telephone calls with patients.
Analysis of the study data is ongoing. Initial analysis shows that 74% (193/262) of enrolled patients with a severe infection of the external auditory canal (the tube running from the outer ear to the eardrum) had a diagnosis of NOE from study start to the end. There were no clear differences in the demographics, symptoms or blood tests of patients with NOE compared to those with severe otitis externa (SOE), except that NOE patients were more likely to have cranial nerves (nerves in the skull) affected. The bacterium Pseudomonas aeruginosa was the most common organism isolated in both NOE and SOE cases (68.9% vs. 53.1%). Almost all patients with NOE and SOE received antipseudomonal antibiotics (99.5% vs. 96.6%), although more NOE patients received intravenous antimicrobial therapy (91.7% vs. 66.1%) and for longer duration (median 20.0 [IQR 9.0-43.0] vs. 10.0 [IQR 5.0-15.0] days) than patients with SOE. 4.7% of NOE patients and 1.7% of SOE patients received medication to treat fungal infection. Mortality was higher in patients with NOE (11.9%) compared to those with SOE (5.8%). 5.7% (11/193) of NOE patients experienced a relapse in their infection during the one-year follow-up. Further analysis is ongoing to assess scan findings and the relationship between treatment and outcomes.
Our data highlights the high levels of mortality and relapse associated with NOE and the need for future interventional studies to identify the best treatment for this neglected condition. Our data will allow greater understanding of this uncommon infection, inform the development of guidelines for the diagnosis and management of NOE and the design of future trials to identify the best way to treat NOE. The final results of the IONOE study will be published in an open access medical journal so that they are freely accessible to all.
Research on Necrotising Otitis Externa (NOE) at the University of Oxford has been supported by input from patients and their families with lived experience of this ear infection, and their voices can be heard via this link:
https://eur03.safelinks.protection.outlook.com/?url=https%3A%2F%2Ftrack.pstmrk.it%2F3ts%2Fwww.expmedndm.ox.ac.uk%252Fresearch%252Fbone-infection%252FBoneInfection%252FSTUDIES%252Fionoe%2FNBTI%2FGtjCAQ%2FAQ%2F3bcec4e5-31a0-400e-b6ec-ccdb58ed2393%2F1%2FamOatzFz6B&data=05%7C02%7Capprovals%40hra.nhs.uk%7C30fd501cd82e46c2cef908de580adbea%7C8e1f0acad87d4f20939e36243d574267%7C0%7C0%7C639045000847940895%7CUnknown%7CTWFpbGZsb3d8eyJFbXB0eU1hcGkiOnRydWUsIlYiOiIwLjAuMDAwMCIsIlAiOiJXaW4zMiIsIkFOIjoiTWFpbCIsIldUIjoyfQ%3D%3D%7C0%7C%7C%7C&sdata=3kEmYs6bVC42UBOBK0RuQBMAMmhq5VypzaSe0Ot0ALw%3D&reserved=0
We would like to thank all patients who took part in the IONOE study and those who have supported the NOE programme at the University of Oxford for their support.
The IONOE study was performed by the University of Oxford and funded by the Dunhill Medical Trust, Antibiotic Research UK, University of Oxford, The Mason Medical Research Foundation and a Kathleen Harper award from the BMA Foundation. The researchers have no competing interests to declare.
REC name
Scotland A: Adults with Incapacity only
REC reference
22/SS/0019
Date of REC Opinion
6 May 2022
REC opinion
Favourable Opinion