CNS Infections Effect on the Inner Ear

Study Overview
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Brief Summary
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Study on patients with CNS infections.

Detailed Description
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Aims and objectives: The present proposal aims to improve the outcome from central nervous system infections (CNS) by improving the understanding of when and why patients develop hearing loss and other neurological sequelae. The investigators will elucidate the temporal development and restitution of a sensorineural hearing loss and will clarify if any therapeutic window exists, where sequelae can be limited. Also the investigators will investigate if communication between cochlea and cerebrospinal fluid is a window to the intracranial pressure. Background: CNS infections remain diseases with high mortality and morbidity. Among survivors from bacterial meningitis, 30 % suffer hearing loss or deafness arising from injury to the inner ear - the cochlea. From previous work it is known that brain inflammation, brain edema and subsequent pressure changes can be transduced to the inner ear due to communication between the cochlea and cerebrospinal fluid (CSF). The viability of cochlear hair cells can evaluated by non-invasive measurement of otoacoustic (OAE) emissions which are low-intensity sounds from the cochlea (OAE). Methods and materials: The investigators will perform repeated measurements of OAE and Wide Band tympanometry (WBT) in all patients admitted with suspicion of a CNS infection. OAE and WBT will be compared to intracranial pressure (ICP) measured during lumbar puncture as well as clinical-, biochemical- and imaging data. An age-matched control group will be included. At discharge and at follow-up patients will receive a neurological, vestibulare examination, cognitive test and a regular hearing test. Expected outcome and perspectives: From repeated measures during a course of disease, the investigators will elucidate the development of a hearing loss and clarify if any therapeutic window exists, where sequelae can be limited. This is also an opportunity to assess OAE as a non-invasive measure of intracranial pressure which is believed to be among the clinical complications responsible for a poor outcome.

Official Title
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CNS Infections Effect on the Inner Ear

Conditions
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CNS Infection, Inner Ear Hearing Loss, Vestibular Abnormality, Inner Ear Inflammation, Hearing Loss, Sensorineural

Intervention / Treatment
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* Diagnostic Test: Vestibular function
* Diagnostic Test: OAE/WBT
* Diagnostic Test: Biomarker
* Diagnostic Test: MOCA, eGOS
* Diagnostic Test: Audiometry


Participation Criteria
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Eligibility Criteria
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Inclusion Criteria: Patients with a CNS infection admitted to the hospital. Exclusion Criteria: Patients with known hearing loss

Ages Eligible for Study
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Minimum Age: 18 Years
Maximum Age: 70 Years

Sexes Eligible for Study
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All

Accepts Healthy Volunteers
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Accepts Healthy Volunteers

Study Plan
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How is the study designed?
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Arms and Interventions

| Participant Group/Arm | Intervention/Treatment |
| --- | --- |
| Cohort with CNS infections<br>Otoacoustic emissions (OAE), Wide Band Tympanometry (WBT), Vestibular function tests. Audiometry. MOCA, eGOS are cognitive tests. Biomarker is a protein found in the inner ear examined in the cerebral fluid. | Diagnostic Test: Vestibular function<br>* Vhit, Caloric test<br>Diagnostic Test: OAE/WBT<br>* Oto acoustic emissions Wide Band Tympanometry<br>Diagnostic Test: Biomarker<br>* Biomarker examination<br>Diagnostic Test: MOCA, eGOS<br>* Cognitive tests<br>Diagnostic Test: Audiometry<br>* Hearing test<br>|
| OAE/WBT control: Healthy individuals<br>Otoacoustic emissions in normal position with head. Otoacoustic emission in different head positions. | Diagnostic Test: OAE/WBT<br>* Oto acoustic emissions Wide Band Tympanometry<br>|
| OAE/WBT control: Systemic infection<br>Otoacoustic emission during admission | Diagnostic Test: OAE/WBT<br>* Oto acoustic emissions Wide Band Tympanometry<br>|
| OAE/WBT control: ICP changes<br>Otoacoustic emission on patients without an CNS infection before and after elective lumbare puncture with measurement of intracranial pressure (ICP). | Diagnostic Test: OAE/WBT<br>* Oto acoustic emissions Wide Band Tympanometry<br>|
| Biomarker control<br>Inner ear biomarkers in patients without CNS infection. Inner ear fluid examination from patients that underwent elective cochlea implantation. | Diagnostic Test: Biomarker<br>* Biomarker examination<br>|

What is the study measuring?
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Primary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Cochlear damage | Assess the frequency and timely evolution of sensorineural hearing loss by using OAE/WBT and audiometry. | Day1-90 | 

Secondary Outcome Measures

| Outcome Measure | Measure Description | Time Frame |
| --- | --- | --- |
| Vestibular function loss | Assess the frequency of vestibular function loss by using VHit and Caloic tests. | Day 1-90 | 
| Identifying biochemical markers in CSF during a CNS infection | Identify biomarkers, such as Cochlin, in CSF and assess their ability to predict sequelae. | Day 1-90 | 
| Cognitive impairment | Assess the frequency and serverity of cognitive impariment by using MOCA scores. | Day 90 |