The presenting symptoms and signs of sarcoidosis are quite variable. In ten to twenty percent of cases, this disorder is discovered incidentally in asymptomatic patients on a routine chest x-ray. Typically, sarcoidosis patients present with constitutional symptoms such as fatigue, malaise, fever, anorexia, and weight loss. Twenty to forty percent of patients have an acute or subacute presentation with symptoms developing over weeks. The vast majority (40-70%) of patients have an insidious, chronic presentation which develops over months. Signs of the disease include: lymphadenopathy, pulmonary infiltrates, ocular lesions, and skin lesions. Because the lung is the most commonly affected organ, most patients have some respiratory problems including chest pain, cough and dyspnea. Ninety percent of patients have an abnormal chest x-ray during their course. Fifty percent of patients have permanent lung abnormalities.

Approximately five percent of patients with systemic sarcoidosis have the variant which affects the nervous system termed "neurosarcoidosis" (4-6). However, only half of these patients have neurologic symptoms (6). Neurosarcoidosis can affect practically any part of the central or peripheral nervous system (7). However, it has a predilection for the base of the brain (3). When intracranial, it tends to involve the cranial nerves, meninges, optic chiasm, hypothalamus, and pituitary (4,6,8). It can also involve the parenchyma of the brain and ependymal lining, and rarely present as a mass lesion worrisome for a tumor (9). Signs of intracranial involvement include: headache, lethargy, polydipsia, polyuria, hydrocephalus, seizures, decreased visual acuity, papilledema, and optic atrophy (3).

Of the cranial nerves, the facial (seventh) is the most commonly affected and usually presents as a transient unilateral lower motor neuron deficit (3). The triad of chronic uveitits, parotitis, and facial nerve involvement is fairly common and has been termed "Uveoparotid Syndrome" (3). The optic nerve is the second most commonly involved cranial nerve, occurring in 5% of the cases of neurosarcoidosis. Symptoms of optic nerve involvement include blurred vision, field defects, blindness, and pupillary abnormalities. An exam of the optic disk may reveal edema of the optic disk, optic neuritis or optic atrophy. The glossopharyngeal and vagus nerves are the next most commonly involved cranial nerves and their involvement can cause hoarseness or palate dysfunction. With involvement of the eighth cranial nerve, patients have changes in their hearing.

When the meninges are involved patients present with an aseptic or tuberculous meningitis which may be recurrent (3).

Seizures are present in 5-25% of patients with neurosarcoidosis. Jacksonian, psychomotor, and myoclonic variants have been documented with grand mal predominating. Unfortunately, presence of seizures portends a bad outcome. Those with seizures are more likely to have a progressive, relapsing course than others with neurosarcoidosis. In one study the five patients who dies of the disease rather than of another cause all had seizures. Seventy five per cent of those with seizures failed to respond well to steroids.

Psychological manifestations of neurosarcoidosis may include apathy, lack of judgment or memory loss. Agitation, hallucination, and other symptoms can also occur.

Sarcoidosis can also invade the spinal cord and cause a myelopathy(10-14). Also, peripheral neuropathy of one or more nerves occurs in 6 to 18% of patients with neurosarcoidosis (6,15). It can affect motor or sensory nerves and be detected by EMG studies (7).