[Spastic paraplegia in Sjögren's syndrome associated with mixed connective tissue disease (MCTD)--a case report]

A case of spastic paraplegia in Sjögren's syndrome associated with mixed connective tissue disease is reported. In this 49-year-old woman spastic gait and arthralgia developed at the age of 23 years and progressed chronically. On neurologic examination, supranuclear paresis of facial nerve was observed. Deep tendon reflexes were hyperactive in the jaw, upper and lower extremities. Serological tests showed that anti-nuclear, anti-RNP, and anti-SS-A antibodies were positive. Spinal fluid analysis showed that rate of de novo central nervous system (CNS) IgG synthesis was increased, and C3/C4 ratio was elevated. CT scans of the brain showed calcifications at bilateral basal ganglia, dentate nucleus and cerebellar vermis. An electroencephalogram revealed diffuse slowing, and 123I-IMP brain scans revealed decreased cerebral blood flow. MRI of brainstem and cervical cord were normal. These findings suggested that corticospinal tracts upper the brainstem were severely affected, and that there were multifocal latent lesions in the CNS. Mechanisms of the CNS involvement were supposed to be both autoimmune abnormality in the CNS, and vascular impairment.