[Neurologic manifestations of primary Gougerot-Sjögren syndrome]

Primary Sjögren's syndrome is one of the commonest autoimmune connective tissue diseases. Neurological complications occur in about 20 p. 100 of primary Sjögren's syndrome patients. It most frequently involves the peripheral nervous system, predominantly sensorimotor and sensory polyneuropathy. Sensory neuronopathy and trigeminal nerve involvement are less frequent but quite suggestive of primary Sjögren's syndrome. Among central nervous system involvements, focal or multifocal lesions of the brain or the spinal cord are the most frequent. Diffuse encephalic involvement may present either as an aseptic meningoencephalitis or as a cognitive impairment. It is not clear whether psychiatric manifestations (mostly mood and personality disturbances) have an organic substratum or are the psychological consequence of the disability induced by a chronic disease such as Sjögren's syndrome. The response to corticosteroids or immunosuppressive therapy is unpredictable in neurological complications of primary Sjögren's syndrome. The pathophysiology of these complications remains unknown. Different mechanisms could be assumed depending on the neurological manifestations: vasculitis in polyneuropathies and multiple mononeuropathies, humoral and/or cellular mediated immune response against neurones in sensory neuronopathy. In central nervous system involvement, each of these mechanisms could occur.