The neuropsychiatric disorder in systemic lupus erythematosus: evidence for both vascular and immune mechanisms

As part of a prospective survey of systemic lupus erythematosus (SLE) a detailed collaborative study of the clinical, psychiatric, and laboratory features in 15 patients with nonfocal neuropsychiatric disease has been undertaken. In addition to conventional clinical and psychometric evaluation, electroencephalograph, and cerebrospinal fluid analysis, the study included the assessment of cerebral blood flow with oxygen-15 brain scans and serological testing for the presence of antineuronal and lymphocytotoxic antibodies. Of the 15 patients 12 had psychiatric manifestations, while 13 had various neurological abnormalities. All except 2 episodes of cerebral disease were transient. Striking abnormalities in cerebral blood flow and metabolism were seen in 12 patients, even in the presence of subtle clinical features. Sequential scans showed that improvement in clinical features was accompanied by a reversal of scan abnormalities. All sera contained brain-reactive antibody, either antineuronal IgG antibody (13) or lymphocytotoxic IgM antibody (12) or both (10), though there was an inconsistent association between clinical features and antibody titre. It is suggested that transient disturbances of cerebral vascular function in SLE might allow brain-reactive antibodies from the circulation access to cerebral tissue. In this way the nature of the neuropsychiatric abnormalities would depend on both vascular and immunopathogenic mechanisms.