Polymorphous exudates and atypical mononuclear cells in the cerebrospinal fluid of patients with Sjögren's syndrome.

Central nervous system (CNS) complications of Sjögren's syndrome are now well recognized. To determine if any of the pathologic changes in the CNS in patients with Sjögren's syndrome were reflected in the cellular composition of cerebrospinal fluid (CSF), we examined the CSF of 14 patients with Sjögren's syndrome and neurologic symptoms and compared the differential cell counts in those cases with those of 14 control patients with similar neurologic symptoms. Patients with Sjögren's syndrome had polymorphous (mixed) inflammatory exudates in CSF, composed predominantly of lymphocytes, but including variable numbers of plasma cells, neutrophils and erythrocytes. In addition, the CSF of all patients with Sjögren's syndrome contained large, atypical, morphologically distinct mononuclear cells. The mean percentage of these cells in the CSF of patients with Sjögren's syndrome (8.3 +/- 1.9) was significantly higher (p less than 0.001) than that observed in the control patients (0.7 +/- 0.2). These results suggest that involvement by Sjögren's syndrome may be suspected by noting a polymorphous exudate containing characteristic atypical mononuclear cells in CSF obtained by lumbar puncture.