Zvonimir Lević

Uric acid levels in sera from patients with multiple sclerosis

Abstract The levels of uric acid (UA), a natural peroxynitrite scavenger, were measured in sera from 240 patients with multiple sclerosis (MS) and 104 sex- and age-matched control patients with other neurological diseases (OND). The mean serum UA concentration was lower in the MS than in the OND group, but the difference did not reach the level of statistical significance (P=0.068). However, the mean serum UA level from patients with active MS (202.6+67.1 μmol/l) was significantly lower than that in inactive MS patients (226.5+78.6 μmol/l; P=0.046) and OND controls (P=0.007). We found a significant inverse correlation of serum UA concentration with female gender (P=0.0001), disease activity (P=0.012) and duration (P=0.017), and a trend towards an inverse correlation with disability as assessed by EDSS score, which did not reach statistical significance (P=0.067). Finally, multivariate linear regression analyses showed that UA concentration was independently correlated with gender (P=0.0001), disease activity (P=0.014) and duration of the disease (P=0.043) in MS patients. These findings suggest that serum UA might serve as a possible marker of disease activity in MS. They also provide support to the potential beneficial therapeutic effect of radical-scavenging substances in MS.

Interleukin-12 and tumor necrosis factor-α levels in cerebrospinal fluid of multiple sclerosis patients

Concentrations of interleukin (IL)-12 and tumor necrosis factor-alpha (TNF-alpha) in cerebrospinal fluid (CSF) were measured in patients with multiple sclerosis (MS) and control patients with non-inflammatory neurological diseases (NIND) by an enzyme-linked immunosorbent assay. TNF-alpha was detectable in the CSF of 60% of the patients with active MS, none of those with inactive MS and 29% of patients with NIND. CSF concentrations of TNF-alpha correlated with the degree of disability in MS patients (P < 0.05). Detectable levels of IL-12 were found in 10% of the MS CSF samples and 18% of NIND CSF samples. There was a significant relationship between CSF concentrations of IL-12 and those of TNF-alpha in MS patients (P < 0.05); no relationship was observed between the presence of IL-12 and disease activity or severity. These findings further stress the involvement of T helper 1 type-response within the central nervous system in MS.

A 44-month clinical-brain MRI follow-up in a patient with B12 deficiency

We report a 51-year-old woman with vitamin B12 deficiency who presented with slight megaloblastic anemia and severe neurologic deficits associated with multiple focal and confluent T2-weighted white matter hyperintensities on brain MRI. Forty-four months after initiation of hydroxocobalamin therapy, there was clinical improvement and striking reduction in the MRI abnormalities. B12 deficiency should be considered in the differential diagnosis of neurologic disorders associated with multiple areas of white matter hyperintensities on T2-weighted brain MRI.

Nitric oxide metabolites and interleukin‐6 in cerebrospinal fluid from multiple sclerosis patients

Interleukin‐6 (IL‐6) and nitric oxide (NO) are implicated in the pathology of multiple sclerosis (MS). We have investigated the levels of these mediators in the cerebrospinal fluid (CSF) from 50 patients with MS and 23 control subjects. Mean CSF IL‐6 level was higher in the total MS group in comparison with controls, but not significantly, whilst the difference between patients with stable MS and controls reached the level of statistical significance. Mean CSF nitrite/nitrate level was significantly higher in the total MS group compared with the control group, as well as in active MS patients versus controls. There was significant difference neither in the mean CSF IL‐6 nor in nitrite/nitrate levels between active and stable MS patients. Interestingly, we observed a significant negative correlation between IL‐6 and nitrite/nitrate levels in the CSF in the total MS group. Such a trend existed in both subgroups with active and stable MS, but without reaching the level of statistical significance. Our data further support the involvement of IL‐6 and NO in ongoing pathological processes in MS, suggesting their potential interplay within the central nervous system in this disease.

Prevalence of multiple sclerosis in Belgrade, Yugoslavia.

Objectives – To estimate the distribution of multiple sclerosis in the Belgrade population. Methods– All persons who were affected and/or died from multiple sclerosis (Posers criteria), with residence in the Belgrade region had been collected from January 1, 1985 to December 31, 1996. Prevalence was adjusted by direct method, using world population. Results– From 1985 to 1996, 823 patients were suffering from multiple sclerosis. Sex ratio was 1:1.9. The mean age at onset was 32.2±9.8 years. A relapsing–remitting course of multiple sclerosis was reported in 50.7% patients, secondary progressive in 36.4% patients, and primary progressive in 12.9% patients. On December 31, 1996, age‐adjusted prevalence of multiple sclerosis in Belgrade was 41.5/100,000, 28.2/100,000 for males, and 54.1/100,000 for females. During the period studied, statistically highly significant increasing trend of multiple sclerosis prevalence was observed (P=0.0001). Conclusions– According to findings presented in this study, Belgrade is an area with high prevalence of multiple sclerosis.

Serum interleukin-12 levels in patients with multiple sclerosis

Increasing body of evidence which suggests a crucial role for interleukin (IL)-12 in modulating immune responses in multiple sclerosis (MS) prompted us to analyze IL-12 in serum from MS patients. We measured the sera concentrations of IL-12, tumor necrosis factor (TNF)-alpha and transforming growth factor-beta1, in 21 MS patients and 13 patients with non-inflammatory nervous diseases. In clinically active MS, serum levels of IL-12 were detectable in 53% and TNF-alpha in 40% of patients. None of the patients with clinically inactive MS had detectable IL-12 and TNF-alpha sera levels. Analysis of serum concentrations of all three cytokines revealed no significant differences between MS patients and controls. These findings provide further evidence that both IL-12 and TNF-alpha might have an active role in immunopathogenesis of MS.

Survival of Multiple Sclerosis Patients in the Belgrade Population

The aim of this study was to estimate survival rates of multiple sclerosis (MS) patients in the Belgrade population, Yugoslavia, and furthermore, to determine the prognostic value of some demographic and clinical variables for survival. The cumulative survival probability was calculated by the Kaplan-Meier method. The prognostic value of different variables was assessed by univariate and multivariate analyses using the Cox regression model. In the Belgrade population, the cumulative 25-year survival probability of MS patients and the mean survival time from MS onset were 73.2% and 38 years, respectively. The univariate analysis showed that survival was significantly related to sex, age at onset, course of disease and monoregional initial symptoms. A multivariate model demonstrated that a relapsing-remitting course of MS and monoregional onset were predictors of a better prognosis. The presence of motor symptoms at the onset was found to be an independent predictor of a poorer outcome of MS.

Raised cerebrospinal fluid nitrite and nitrate levels in patients with multiple sclerosis: no correlation with disease activity

A growing body of evidence implicates excessive generation of nitric oxide (NO) within the central nervous system (CNS) in multiple sclerosis (MS). The aim of our study is to analyse nitrite and nitrate as end products of NO in the cerebrospinal fluid (CSF) from MS patients and correlate the concentrations with clinical characteristics of the disease. CSF nitrite and nitrate concentrations were measured after reduction of nitrate, by Griess reaction, in 105 MS patients, 27 patients with non-inflammatory neurological disorders (NIND) and 13 individuals without neurological disorder (Co). Mean CSF nitrite and nitrate concentrations were significantly higher in patients with MS and NIND compared with the Co patients (9.44 and 8.68, respectively, versus 6.85 μM; P=0.0001 and P=0.031, respectively). There was no significant correlation between CSF nitrite and nitrate concentrations and activity, phase, severity and duration of MS. Our data are in agreement with the results of previous studies which have demonstrated raised concentrations of CSF NO metabolites in MS patients, providing further evidence for NO involvement in MS. The lack of correlation between NO metabolites and disease activity speaks in favour of the possible dual role of NO, as both immunoregulatory and proinflammatory molecule, in the pathogenesis of MS.

Primary progressive multiple sclerosis: clinical and paraclinical characteristics with application of the new diagnostic criteria.

The aim of our study was to analyse clinical and paraclinical characteristics of patients with multiple sclerosis (MS) with previous diagnosis of primary‐progressive (PP) MS according to the Posers criteria and further investigate if they fulfil the McDonalds diagnostic criteria for this disorder. A total of 561 MS patients were registered in the database at the Institute of Neurology, Belgrade, from 1 January 1997 to 31 December 2000 and 63 of them (11.2%) with previous diagnosis of PPMS were analysed retrospectively. Male/female ratio was 1.3:1 and mean age at onset 33.2 years. Most frequent at onset were pyramidal (in 73% of patients) and sensory symptoms (in 41% of patients); 74.6% of patients had greater than or equal to nine brain magnetic resonance imaging (MRI) lesions. Intrathecal oligoclonal immunoglobulin G (IgG) was detected in 96.7% and prolonged visual evoked potentials (VEP) P100 latency in 82.4% of patients. Of the total study group of 561 patients, 10.2% fulfilled the recently recommended McDonalds diagnostic criteria for the diagnosis of PPMS. Our findings further support the significance of the brain/spinal cord MRI, cerebrospinal fluid and VEP findings for precise diagnostic assessment in patients with suspected PP form of MS.

CNS tumours : oligoclonal immunoglobulin D in cerebrospinal fluid and serum

Oligoclonal immunoglobulin D bands were detected by isoelectric focusing in 7 out of 25 unconcentrated cerebrospinal fluid (CSF) samples obtained from patients with tumours of the central nervous system (CNS). The tumours were confirmed by clinical and histological findings. Two patients with CNS malignancy had intrathecal synthesis of oligoclonal bands both IgD and IgG. Four patients with a variety of CNS tumours had a systemic IgD immune response but no oligoclonal IgG bands. One patient with the most malignant tumour histology had a systemic IgD response as well as local synthesis of IgG. The study reveals several new aspects regarding CNS tumours: they are immunologically active and are capable of invoking oligoclonal immunoglobulin production both within the CNS and systemically. Multiple immunoglobulin activation can be found in malignant CNS tumours, and systemic IgD production may occur independently from IgG synthesis and may represent an immune response to a neoantigen produced in the CNS compartment.