Approximately 5–10 percent of people with sarcoidosis of other organs (e.g. lung) develop central nervous system involvement.

Visual problems may also be the result of papilledema (swelling of the optic disc) due to obstruction by granulomas of the normal cerebrospinal fluid (CSF) circulation.

Obstruction of the flow of cerebrospinal fluid, too, can cause headaches, visual symptoms (as mentioned above) and other features of raised intracranial pressure and hydrocephalus.

[1] Granulomas in the pituitary gland, which produces numerous hormones, is rare but leads to any of the symptoms of hypopituitarism: amenorrhoea (cessation of the menstrual cycle), diabetes insipidus (dehydration due to inability to concentrate the urine), hypothyroidism (decreased activity of the thyroid) or hypocortisolism (deficiency of cortisol).

[1] Psychiatric problems occur in 20 percent of cases; many different disorders have been reported, e.g. depression and psychosis.

[1] Other symptoms due to sarcoidosis of other organs may be uveitis (inflammation of the uveal layer in the eye), dyspnoea (shortness of breath), arthralgia (joint pains), lupus pernio (a red skin rash, usually of the face), erythema nodosum (red skin lumps, usually on the shins), and symptoms of liver involvement (jaundice) or heart involvement (heart failure).

Other investigations that may be performed in any of the symptoms mentioned above are computed tomography (CT) or magnetic resonance imaging (MRI) of the brain, lumbar puncture, electroencephalography (EEG) and evoked potential (EP) studies.

This now obsolete test had a high (85 percent) sensitivity, but required spleen tissue of a known sarcoidosis patient, some of which was injected into the skin of a suspected case.

[1] Lumbar puncture may demonstrate raised protein level, pleiocytosis (i.e. increased presence of both lymphocytes and neutrophil granulocytes) and oligoclonal bands.

If this is effective, the dose may gradually be reduced (although many patients need to remain on steroids long-term, frequently leading to side-effects such as diabetes or osteoporosis).

Methotrexate, hydroxychloroquine, cyclophosphamide, pentoxifylline, thalidomide and infliximab have been reported to be effective in small studies.

The disease is most prevalent in Northern European countries and the highest annual incidence of 60/100,000 is found in Sweden and Iceland.

In the United States sarcoidosis is more common in people of African descent than Caucasians, with annual incidence reported as 35.5 and 10.9/100,000, respectively.

[12] The American television personality and actress Karen Duffy wrote Model Patient: My Life As an Incurable Wise-Ass on her experiences with neurosarcoidosis.