NEUROSARCOIDOSIS

Sarcoidosis can occur in almost any organ. In 5 to 15% of patients with sarcoidosis, the disease occurs somewhere in the nervous system. This is called neurosarcoidosis.

The information on this page has been compiled with the help of sarcoidosis specialist Dr D. Kidd, Consultant Neurologist.

Download the Leaflet:

Sarcoidosis and the Nervous System

Cranial Neuropathy

Half of all patients with neurosarcoidosis have a simple cranial neuropathy such as a weakness of one half of the face. Sometimes other nerves are affected causing problems with hearing, numbness of the face, weakness of the tongue, difficulty swallowing or double vision. Patients with cranial neuropathies respond well and quickly to steroids and the condition usually fully resolves itself.

Other Forms of Neurosarcoidosis

Of the remaining half of patients, two thirds have leptomeningitis, one quarter pachymeningitis and the remainder the vasculitic form. These cases are much more serious and require urgent evaluation and treatment:

1. Leptomeningitis. In this process the inner lining of the brain becomes inflamed and the inflammation speeds quickly in to the brain which itself swells up. This can cause a multitude of symptoms, depending mostly on the site of entry and the severity of the inflammation. Most patients develop headache, drowsiness, slowness of thinking and then other features such as weakness or numbness, balance, visual and hearing problems. The MRI scan is always abnormal, and the spinal fluid shows inflammatory cells.
2. Pachymeningitis. The outer lining of the brain or spinal cord becomes inflamed. This causes headaches and focal neurological signs such as weakness or numbness down one side, and occasionally seizures. Patients have abnormal brain scans and occasionally can be diagnosed with brain tumours incorrectly because of what is shown on the scan.
3. Vasculitis. This is the least common form of neurosarcoidosis and is caused by inflammation within the blood vessels of the brain. The blood vessels can become blocked, and small areas of inflammation can be seen on the surface of the brain on MRI scans. Sometimes how vasculituis appears on a scan can be misinterpreted as strokes or multiple sclerosis. Occasionally the blood vessels can become narrowed and misshapen.

Diagnosis can usually be made after blood and spinal fluid tests and an MRI scan, but occasionally a biopsy of the brain or spinal cord is necessary.

Treatment is with a high dose of steroids, suppression of the immune system with chemotherapy, and immunotherapy drugs such as an infliximab. Treatment is needed for at least 5 years. Most patients respond well to this medication, but they need to be monitored carefully and most importantly by a neurologist with experience of the disease. This should be within a multidisciplinary team consisting of respiratory physicians, rheumatologists, endocrinologists, immunologists and specialist nurses.

Peripheral Neuropathies

When the peripheral nervous system (bodily nerves) is involved, a condition known as peripheral neuropathy may develop. This occurs in around 10% of patients, and causes numbness and occasionally weakness of the hands and feet. It tends to be painless and mild and does not worsen.

Some patients can have a severe problem known as acute demyelinating polyradiculoneuropathy, which develops at the onset of the systemic disease, but this improves with treatment. Some develop mononeuropathies when only one nerve is affected, for example in the hand.

Vasculitic neuropathy is a rarer and more severe condition which always deteriorates quickly and so requires urgent treatment.

Small Fibre Neuropathy

Small fibre neuropathy is common; patients complain of burning feet and occasionally also in the hands. In most patients the condition is irritating but not deteriorating but in some it can be very severe and painful. Treatment is always helpful; anti-neuralgia medications (such as Gabapentin and Duloxetine) work well and those with very severe pain respond to infliximab.

Polymyositis and Muscle Pain

When muscle is affected it may be painful and cause weakness – this is known as polymyositis. It may also be a slowly deteriorating problem with muscle wasting and cause no pain. The polymyositis form responds to treatment, but the rare wasting form does not. Muscle involvement occurs in only 5% of cases.

Techniques to Understand your Condition

If your symptoms suggest neurosarcoidosis your doctor will refer you to a neurologist. This doctor will map neurological signs and symptoms. A physical examination is always part of a consultation with a neurologist. If necessary, they will also arrange any additional tests such as EEC (Electro Encephalo Gram) and MRI (Magnetic Resonance Image).

Early Diagnosis

The effectiveness of treatment in severe forms of neurosarcoidosis can be improved considerably by early and aggressive treatments given after investigation in specialist centres. Patients need to ensure that their treating Doctors understand neurosarcoidosis sufficiently. SarcoidosisUK can help them find the units providing expert care.

Outlook

The earlier the treatment is given and the stronger the treatment used for the circumstance, the more likely it is that patients will respond well and recover reasonable neurological function. Some patients suffer damage to the nervous system which cannot be corrected, but many others do improve. Thankfully nowadays neurosarcoidosis is rarely a fatal disease.

Page last updated: January 2023.

Neurosarcoidosis Videos

Dr Tarunya Arun – Neurosarcoidosis

For Sarcoidosis Awareness Month 2024, we reached out to Dr Tarunya Arun, Consultant Neurologist at the University Hospitals Coventry and Warwickshire to create this short video for us, thank you!

She discusses neurosarcoidosis, some of the challenges with diagnosis and management, and looks at managing some of the wider aspects of this multi-system condition.