[Neuroradiological manifestations of primary Sjögren's syndrome].
Primary Sjögren's syndrome (PSS) is considered as the most frequent connective tissue disease. Neurological complications may affect the peripheral nervous system and to a lesser extent the central nervous system. Neurological manifestations often precede or reveal SSP. Peripheral neuropathy is the most common and well-known neurological complication of PSS. Its frequency is about 20-30 percent of patients. Distal sensory or sensorimotor axonal neuropathy is the most frequent followed by sensory neuronopathy, the only neurological complication characteristic of SSP. Recently, several cases of motor neuron syndrome have been reported suggesting that it could be a neurological complication of SSP. CNS involvement consists of cerebral or spinal cord involvement and its frequency is debated. Cerebral dysfunction may be focal or multifocal according to the number and location of lesions. Its course may be acute, remittent or progressive. Cognitive dysfunction and psychiatric manifestations seem to be frequent in SSP but this needs to be confirmed by further studies. Spinal cord involvement consists of acute myelitis or progressive myelopathy. In CNS involvement, there is no correlation between clinical findings and results of CSF study or MRI which can be normal or disclose unspecific abnormalities. For all neurological complications, response to corticosteroids or immunosuppressive therapy is unpredictable. As neurological manifestations in SSP are miscellaneous, SSP diagnosis should be considered in any unexplained neurological setting because sicca syndrome is often mild or asymptomatic and immunological abnormalities or other extraglandular manifestations of PSS may be lacking.