An observational study of inflammation in the central nervous system in patients with bipolar disorder.

OBJECTIVES: The potential influence of infections and immunological changes on the aetiology and pathogenesis of bipolar disorder (BD) has been discussed. Our aim was to detect intrathecal specific antibody synthesis against the neurotropic infectious agents that have previously been linked to BD. METHODS: Paired cerebrospinal fluid (CSF) and serum samples from 40 patients with BD were analysed using the enzyme-linked immunosorbent assay to detect the concentration of antibodies against the following neurotropic infectious pathogens: Toxoplasma gondii (T. gondii), herpes simplex virus (HSV) types 1 and 2, cytomegalovirus (CMV), and Epstein-Barr virus (EBV). The specific antibody index (AI) was calculated, and an AI > 1.4 was considered to be evidence of intrathecal specific antibody synthesis. Twenty-six patients with pseudotumour cerebri served as controls. RESULTS: Eight out of 40 patients with BD displayed specific intrathecal antibody synthesis against at least one of the tested neurotropic agents compared to only one patient in the control group (p = 0.061, not significant). Of these eight patients with BD, no significant prevalence of any particular neurotropic pathogen was evident. Five out of 40 patients with BD showed oligoclonal bands in the CSF, suggestive of a chronic immune reaction in the central nervous system (CNS). CONCLUSIONS: We found evidence for increased production of antibody in the CSF of individuals with BD. However, the trend for polyspecific intrathecal antibody synthesis, as well as the presence of oligoclonal bands, might indicate activation of the intrathecal humoral immune system in a subgroup of patients with BD, as it is known to be associated with autoimmune disorders of the CNS.

Impaired functioning in euthymic patients with bipolar disorder--HSV-1 as a predictor.

There is a possible association between infectious agents and psychiatric disorders. Previous studies in the US provided evidence for cognitive impairment correlated with Herpes simplex virus type 1 (HSV-1) infection. For a replication study in Europe we chosed individuals diagnosed with bipolar disorder to analyse the correlation with HSV-1 infection. Antibody prevalence was analyzed by using solid phase immunoassay techniques. Cognitive functioning was tested with the Repeatable Battery for the Assessment of Neuropsychological Status (RBANS) Form A, the Trail Making Test A&B, and two subtests from the WAIS III: the Letter Number Sequencing Task and the subtest on information. History and psychopathology was assessed using structured interviews and validated rating scales (SCID, HRSD-21, YMRS, PANSS). Additionally, we investigated social functioning and quality of life using self-assessment-scales (SAS, LQLP). Prevalence rates of antibodies against diverse infectious agents did not differ significantly between patients and controls. We found a significant correlation between cognitive impairment in patients with bipolar disorder and the prevalence of antibodies directed against HSV-1. Cognitive functions were significantly impaired including language, attention, and immediate memory. The results of this study confirm previous findings suggesting that HSV-1 affects cognitive functions in patients with bipolar disorder. This may also result in more impaired functioning, less quality of life and difficulties in social adjustment.