Endogenous event-related potentials in patients with primary Sjögren's syndrome without central nervous system involvement.

OBJECTIVES: Endogenous cognitive event-related potentials (CERPs) reflect higher-level processing of sensory information and can be used to evaluate cognitive functions. The aim of this paper was to determine whether there are any abnormalities in the electrophysiological parameters of CERPs in patients with primary Sjögren's syndrome (pSS) but without symptoms of central nervous system (CNS) involvement or mental disorder. The analysis of CERP parameters was then correlated with the clinical status of the patients and with some of the immunological parameters in the patient group. METHOD: Thirty consecutive patients with pSS (29 females, one male) were included in the study. All the patients underwent CERP examination. RESULTS: There was a significant prolongation of the latency of P300 and N200 potentials in patients with pSS. Abnormalities in electrophysiological parameters of CERPs correlated with the duration of the disease, salivary gland abnormalities, and elevated erythrocyte sedimentation rate (ESR) values. Patients with coexisting chronic fatigue syndrome (CFS) had larger P300 amplitudes. There were no statistically significant changes in the electrophysiological parameters of CERPs in patients with pSS dependent on the presence of peripheral nervous system (PNS) lesions, skin changes, arthritis, abnormalities in white blood cells and the immune system or the levels of blood lipids. CONCLUSIONS: The results of the study suggest the presence of a minor cognitive dysfunction in patients with pSS without symptoms of CNS involvement or mental disorder. Cognitive dysfunction correlated with the disease duration time and the severity of inflammatory changes (salivary gland abnormalities and inflammatory markers in the blood). Further and larger longitudinal studies are necessary for confirmation of this correlation.

Diffusion tensor imaging findings in the multiple sclerosis patients and their relationships to various aspects of disability.

BACKGROUND: The aim of the study was to assess microstructural changes within strategic brain regions in multiple sclerosis (MS) patients, using diffusion tensor imaging (DTI), with regard to various aspects of disability. MATERIAL AND METHODS: The study comprised 50 patients with relapsing-remitting MS (37 women, 13 men, mean age 36.4 yrs) and 27 age- and sex-matched controls. Using DTI, fractional anisotropy (FA) and apparent diffusion coefficient (ADC) values were obtained within corpus callosum (CC), both thalami (TH) and middle cerebellar peduncles (MCP). Disability was assessed using Expanded Disability Status Scale (EDSS), MS Functional Composite (MSFC), Symbol Digit Modalities Test (SDMT) and Fatigue Severity Scale (FSS). DTI indices were compared between the patients and controls and in the MS group - referred to disability measures. RESULTS: Significant decrease in FA and increase in ADC within CC and both TH were found in MS patients compared to the controls. DTI indices within CC and TH correlated significantly with SDMT score, and within TH and MCP - with MSFC manual dexterity measure. CONCLUSIONS: Changes in DTI measures in normal appearing white and grey matter in the MS patients indicate subtle alterations of the tissue integrity. An occult damage to the strategic brain regions may contribute to various aspects of disability due to MS.