Evidence of intrathecal immunoglobulin synthesis in stroke: a cohort study.

BACKGROUND Immune mechanisms are included in stroke pathophysiologic factors, but the frequency and role of intrathecal antibodies is unclear and diagnostic tests are not routinely performed on cerebrospinal fluid (CSF). OBJECTIVE To determine the frequency of intrathecal immunoglobulin synthesis in a well-characterized cohort of patients who experienced “noninflammatory”acute stroke. DESIGN Retrospective cohort study. SETTING University hospital neurology department. PATIENTS Patients (n=318) with stroke who were undergoing lumbar puncture during diagnostic workup and 79 control patients. RESULTS Cerebrospinal fluid–specific immunoglobulin(IgG, IgM, and IgA) synthesis was significantly(P.001) more frequent after stroke (24.8%) compared with the incidence in age- and sex-matched controls(2.5%). Furthermore, 31.3% of stroke patients demonstrated blood-brain barrier dysfunction and 18.1% displayed pleocytosis. CONCLUSION The strong association between CSF-specific immunoglobulin synthesis and stroke suggests a role in the development of cerebral ischemia and might constitute an immunologically defined stroke subgroup.