Sarcoidosis is a condition characterised by inflammatory changes in multiple organs, but predominantly in the lungs and lymph glands. It causes formation of abnormal masses of inflammatory tissues called as granuloma in the affected organs. Over a period of time, these nodules or granulomas alter the normal functioning and structure of the affected organs. When sarcoidosis happens in the nervous system it is known as neurosarcoidosis. Let us see the symptoms, causes, diagnosis and treatment of the disease.
What is Neurosarcoidosis?
Neurosarcoidosis is a condition where sarcoidosis affects the nervous system, i.e. there is inflammation in the brain, spinal cord and other areas of the nervous system. This condition can affect any part of the nerve supply including the facial nerves and other nerves that control the eyes, hearing, taste and smell. It can also affect the spinal cord which over a period of time can lead to weakness in the upper and lower extremities, discomfort while walking and loss of control over the bladder. It may also affect parts of the brain which are involved in regulation of body function. This in turn can result in sleep issues, temperature fluctuation and stress. Peripheral nerve involvement can lead to sensory loss and weakness in the muscles. In certain cases, it can also affect the pituitary glands. It is also known as sarcoidosis of the nervous system.
Symptoms of Neurosarcoidosis
The symptoms of neurosarcoidosis depend on the area being affected and the extent of involvement. The most common symptoms are as follows:
Symptoms of Neurosarcoidosis with involvement of the pituitary glands:
- Change in menstrual cycle
- Fatigue and excessive tiredness
- Increased urination
- Increased thirst.
Symptoms of Neurosarcoidosis with involvement of parts of the brain and cranial nerves:
- Decreased hearing
- Disorientation and confusion
- Dizziness and vertigo
- Dementia or memory impairment
- Abnormal sensation of movement
- Visual impairment with double vision in some cases
- Facial muscle weakness with drooping
- Loss of sense of smell and taste
- Speech abnormalities
- Psychiatric issues.
Symptoms of Neurosarcoidosis with involvement of the peripheral nerves:
- Restricted movement of any body part
- Abnormal sensation of numbness in any body part
- Weakness or any body part.
Epidemiology of Neurosarcoidosis
Neurosarcoidosis is more common among the age group of 20 to 40 years and more frequent in women than in men. It has been seen that this condition is about 10 to 17 times more frequent in African – American than in Caucasians. It is also more common in people of Scandinavian, German, Irish and Puerto Rican origin. Studies have shown than more 10,000 people in USA have been diagnosed with sarcoidosis.
Prognosis of Neurosarcoidosis
While in some cases the symptoms of Neurosarcoidosis resolves by itself in 4 to 6 months, in certain cases the symptoms last for a long period of time and can even last for a lifetime. Neurosarcoidosis can also lead to permanent disability and even death if left untreated.
Causes of Neurosarcoidosis
The exact cause of sarcoidosis is not known. A large number of studies are being carried out to determine the exact cause of sarcoidosis. The most accepted theory at present is that it is an autoimmune condition caused by suppression of the immune system and abnormal response of the immune system to unknown stimuli. Neurosarcoidosis is caused when symptoms of sarcoidosis spread the nervous system.
Complications of Neurosarcoidosis
The complications vary based on the part of the nervous supply affected by neurosarcoidosis. If left untreated it can lead to permanent loss of neurological function in the area supplied by the nerves affected. In very rare cases, the brain stem may get affected, which can be life threatening.
Diagnosis of Neurosarcoidosis
Neurosarcoidosis is diagnosed by an experienced neurologist based on known history of sarcoidosis and presence of nerve related symptoms. Neurosarcoidosis may be misdiagnosed with other neurological conditions as the symptoms mimics other symptoms associated with hypopituitarism, meningitis, optic neuritis, diabetes insipidus, certain tumors etc. In very rare cases, there may be neurological symptoms without the lungs or other organs being affected. A detailed case history along with clinical examination is done.
In neurosarcoidosis, blood works are often not very helpful. A lumber puncture may be considered to evaluate signs of inflammation. In has been noted that the angiotensin-converting enzyme level found in the cerebrospinal fluid (CSF) is often above the normal limits in patients with neurosarcoidosis. However, this cannot be used as a reliable test. Other investigative studies include MRI of the brain, chest x-ray for determining the signs of sarcoidosis in the lungs and nerve biopsy of the affected nerve. In some cases, EMG may be done for studying the nerve function. Other investigative studies include HRCT scan, pulmonary function breathing test, chest x-ray and bronchoscopy.
How is Neurosarcoidosis Treated?
Neurosarcoidosis or sarcoidosis does not have a definitive treatment. Management involves treatment for symptomatic relief. Oral medications such as corticosteroids and prednisone are prescribed to reduce pain and inflammation. Other medications include methotrexate and plaquenil. Hormone replacement therapy may be considered for supressing the immune system. Physical therapy is advised for improvement of movement. In Neurosarcoidosis patients with difficult walking and other balance and gait issues, a brace, cane, or a walker is provided. Psychiatric disorder and memory impairment are treated with anti-depressants, assistance and other safety measures. Alternate medication such as acupuncture can also be helpful in management of the symptoms of Neurosarcoidosis.
Prevention of Neurosarcoidosis
The only preventive measure that can be taken to avoid occurrence of neurosarcoidosis, is treating sarcoidosis at the right time. Aggressive treatment of sarcoidosis at the right time helps in strengthening the immune system which in turn will help in preventing progression of the disease into the nerves, and this reduce the chances of neurological complications. It is advised to seek medical help immediately, if neurological symptoms such as sudden loss of sensation, body function or movement are noticed in presence of sarcoidosis. Other preventative measures include:
- Regular health check ups
- Maintaining a balanced diet and following a healthy diet which includes a variety of fruits and vegetables.
- Staying adequately hydrated.
- Getting adequate amount of sleep
- Regular exercising and management of weight
- Avoid smoking.
Neurosarcoidosis is a complication of sarcoidosis where the inflammatory symptoms affect the nervous system. It can affect the brain, spinal cord, any part of the nervous system and even the pituitary gland in certain cases. It can affect the facial nerve and alter the sensation of taste, smell and facial expression. When it affects the spinal cord, it can lead to difficulty while walking, weakness in extremities etc. It can also affect the normal functioning of various regulating factors. In extreme cases, it can even lead to permanent disability. A permanent treatment for neurosarcoidosis has not yet been discovered. Hence, a large number of studies are being carried to understand this condition better and also to develop a treatment method.