Neurosarcoidosis is a form of sarcoidosis. It is a long-term (chronic) disease of the central nervous system, which encompasses the brain, spinal cord and optic nerve, and is characterized by inflammation within one or more of those areas. This inflammation can cause the destruction of the coating (myelin) that surrounds and protects nerve fibers (axons). As a result, the damage disrupts the normal flow of messages (nerve impulses) from the central nervous system, causing a reduction or loss of body function.
Neurosarcoidosis most commonly affects the cranial and facial nerves, the hypothalamus area of the brain, and the pituitary gland.
Symptoms of neurosarcoidosis can vary depending on the areas that are affected and can be similar to those of multiple sclerosis (MS).
If the condition is affecting the pituitary gland, symptoms may include:
- Changes in menstrual periods
- Excessive thirst
- Excessive urination
If the condition is affecting the brain or cranial nerves, symptoms may include:
- Confusion, disorientation
- Hearing loss
- Dizziness, vertigo, or abnormal sensations of movement
- Vision problems, such as double vision
- Facial palsy, which is characterized by weakness or drooping of the facial muscles
- Loss of sense of smell
- Loss of sense of taste, abnormal tastes
- Psychiatric disturbances
- Speech impairment
If the condition is affecting peripheral nerves, this can cause symptoms such as:
- Muscle weakness
- Numbness or tingling sensations
- Loss of movement
Causes and Risk Factors
The cause of neurosarcoidosis is unknown. Some factors thought to contribute to risk include infections, immune system disorders and genetics. It usually develops in people between the ages of 20 and 40. It is most common among Swedish and African-American people, although it can occur in anyone.
Patients with a history of sarcoidosis are at an increased risk of developing the condition.
If the patient has a history of sarcoidosis followed by nerve issues, it is highly likely they have developed neurosarcoidosis. Diagnosis of the condition begins with a detailed medical history and neurological examination. Neurosarcoidosis can have symptoms similar to those of other nervous system disorders such as diabetes insipidus, hypopituitarism, optic neuritis, meningitis and certain tumors, so diagnostic tests help rule out other causes and confirm a diagnosis.
These tests may include a magnetic resonance imaging (MRI) scan of the brain and spinal cord as well as a lumbar puncture, also known as a spinal tap. Chest x-rays may be ordered to see if signs of sarcoidosis are present in the lungs. Other tests may include a nerve biopsy of the affected area to confirm the diagnosis.
There is no cure for neurosarcoidosis. Treatment of the condition occurs when patients are experiencing severe or progressive symptoms. Corticosteroids may be given to shorten and lessen the severity of the symptoms by reducing the inflammation. Symptoms of neurosarcoidosis can affect a patient's daily life and physical and occupational therapy may be used to manage symptoms and help patients adjust to living and working situations. Physical aids such as braces or a cane may also be needed.
For some patients, pain management may be needed.
Choosing the right treatment requires careful consideration of the risks and benefits, along with close collaboration with an experienced neurologist with experience in treating the disease, such as those at the Cedars-Sinai's Department of Neurology.