Blood-cerebrospinal fluid barrier impairment as indicator for an immune process in schizophrenia

An impairment of the blood-cerebrospinal fluid barrier (BCB) has repeatedly been described in schizophrenic patients. A BCB impairment can be due to vascular leakage during an inflammatory process, or to neuroleptic treatment. The soluble intercellular adhesion molecule-1 (sICAM-1) has been demonstrated to be a reliable marker for an inflammatory process causing an BCB impairment. To clarify the basis of a BCB impairment in schizophrenic patients, we measured the sICAM-1 levels in CSF of 40 schizophrenic patients. High concentrations of sICAM-1 were found to be related to high concentrations of albumin, IgG and total protein in CSF. A BCB impairment was associated with high levels of sICAM-1. Our data indicate an inflammatory mechanism of BCB impairment in schizophrenics and should enrich the discussion on an expanded immunological diagnosis in schizophrenia.