Upper motor neuron syndrome associated with subclinical Sjögren's syndrome.

We present two patients with primary lateral sclerosis-like upper motor neuron disease accompanying subclinical Sjögren's syndrome. Both patients showed progressive spastic quadriparesis, but neither sensory involvement nor detrusor dysfunction was noted. Lower motor neuron signs were detected only in their late follow-up period. Although sicca symptom was nearly absent, salivary labial gland biopsy revealed marked sialoadenitis in both patients. They also displayed a constellation of findings that suggested an autoimmune etiology closely related to Sjögren's syndrome, including germinal center formation in one patient, and markedly elevated levels of anti-nuclear antibody with abnormal sialography in the other. Both patients showed significant neurological improvement after the initial course of intravenous immunoglobulin therapy. We suggest that the evidence for subclinical Sjögren's syndrome should be sought in patients presenting with selective upper motor neuron involvement.