What is labyrinthitis?
Labyrinthitis is a condition that causes sudden dizziness, balance problems with difficulty walking, often accompanied by nausea and vomiting. The term "labyrinthitis" is commonly used to refer to diseases that affect a part of the ear known as the labyrinth.
The labyrinth’s main function is to help maintain balance. It connects to the brain through a nerve called the vestibulocochlear nerve. These anatomical structures (labyrinth, nerve, and brain) can be affected by different diseases of varying severity, causing similar symptoms.
The labyrinth is present in both ears and functions jointly—alteration in just one ear is enough to trigger the characteristic symptoms. The common belief among patients that dizziness is always caused by labyrinthitis can lead to diagnostic errors with serious consequences. The clinical symptoms of labyrinthitis can be confused with other labyrinth disorders and sometimes with neurological diseases such as a stroke.
Symptoms
The term labyrinthitis is currently a topic of debate among doctors. Some refer to labyrinthitis as vestibular neuritis, believing it to be swelling or inflammation of the nerve that connects the labyrinth to the brain.
Some physicians consider vestibular neuritis to be clinically different from labyrinthitis, with the latter presenting not only dizziness, imbalance, nausea, and vomiting but also hearing changes. Thus, it is called vestibular neuritis when hearing is not affected and labyrinthitis when it is.
Labyrinthitis symptoms appear abruptly, are intense at the onset—especially during the first two days—and generally improve progressively over a few days or weeks. The symptoms can be disabling, sometimes requiring hospitalization for symptomatic treatment. In other cases, patients are hospitalized due to diagnostic uncertainty, to rule out neurological causes of dizziness.
The main symptoms include:
- vertigo: intense dizziness with the false sensation of spinning, as if the environment or the patient is rotating
- dizziness: a feeling of imbalance or instability, as if the person is staggering and has difficulty walking normally
- nausea and vomiting: mainly due to intense vertigo
- hearing loss and tinnitus: in some cases, the condition may cause temporary hearing changes
It is very important to remember that the signs and symptoms of labyrinthitis can be confused with neurological diseases such as a stroke, which requires early diagnosis to avoid sequelae or even death.
Some warning signs may indicate serious causes of dizziness. These signs and symptoms should prompt the patient to seek emergency care immediately. Symptoms such as inability to stand or walk, severe headache or neck pain, motor incoordination with difficulty holding objects, double or blurred vision, drowsiness, or altered consciousness may indicate serious neurological causes.
We must also remember that elderly patients with risk factors for cerebrovascular disease—such as high blood pressure, diabetes, high cholesterol, and smoking—have an increased risk of stroke.
Causes
The cause of labyrinthitis or vestibular neuritis remains uncertain among doctors. The most accepted theory today is that it is an inflammation of the nerve and/or labyrinth that occurs during or after viral infections. Only half of patients recall having infectious symptoms in their medical history. Reports of various viral infections, such as respiratory viruses and herpes zoster (chickenpox virus), can cause inflammation of the nerve and labyrinth.
Diagnosis
Labyrinthitis is often diagnosed in the emergency room. Due to the intensity of symptoms, some patients seek emergency care for their first evaluation. Given the diagnostic difficulty, the attending physician should follow defined protocols for dizziness care and, if uncertain, request a specialist evaluation.
The specialists who assess patients with dizziness are otolaryngologists and neurologists. A detailed medical history and focused clinical examination are the main tools for accurate diagnosis.
To reach a correct diagnosis, the physician should follow these steps:
- medical history: the doctor should ask about the onset of symptoms, recurrence in the past, duration of symptoms, associated symptoms, past medical history, medication use, and any changes in dosage
- physical examination: the clinical exam should focus on specific findings in patients with dizziness such as balance problems, difficulty walking, hearing changes, tinnitus, and eye abnormalities (eye exams provide important information about labyrinth function). The presence of nystagmus (involuntary eye movements) should be carefully evaluated, as well as eye alignment and motor coordination
- additional tests: when labyrinthitis is clinically diagnosed, emergency tests are often unnecessary. Treatment can begin, and further investigation can be done later in a specialist’s office
If a neurological cause of dizziness, such as a stroke, is suspected, imaging tests are essential (brain MRI and MR angiography are considered the most important). Further investigation in the specialist’s office—either otolaryngologist or neurologist—may include tests such as audiometry, video head impulse test, and otoneurological examination, among others.
Treatment
Treatment for labyrinthitis or vestibular neuritis includes addressing infections related to the clinical condition, such as herpes zoster when present. It also involves treating nerve inflammation, dizziness symptoms, and nausea and vomiting. The use of corticosteroids helps reduce nerve inflammation. Antiviral therapy may treat viruses associated with labyrinthitis. Vestibular rehabilitation is a type of physical therapy for the labyrinth. Empirical treatments have limited randomized studies confirming their effectiveness.
Prevention
Preventing complications includes staying well hydrated and avoiding excessive alcohol and caffeine intake. The risk of falls is very high, so patients should avoid sudden movements, move slowly, and ask for help if feeling unsteady. Additionally, they should not drive while experiencing dizziness, avoid climbing stairs or high places, and refrain from extreme sports.
References
Labirintite | Biblioteca Virtual em Saúde MS
Tontura e vertigem - Ministério da Saúde