Relationship of uric acid and lactate levels and neutrophil to lymphocyte ratio (NLR) with Expanded Disability Status Scale (EDSS) in Syrian multiple sclerosis

Background: Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease that affects the central nervous system (CNS). It is a multifactorial disease in which genetic and environmental factors interact to increase the risk of the formation of inflammatory lesions leading to oligodendrocytes damage and gradual demyelination. Expanded Disability Status Scale (EDSS) was used to evaluate the motor disability caused by MS, and it ranges from 0 to 10. MS is accompanied by an increase in oxidative compounds, especially peroxynitrite, in the brain, an imbalance in energy metabolism in nerve cells, and the infiltration of immune cells that stimulate the inflammatory state leading to the formation of demyelinating plaques in the central nervous system. Therefore, This study aimed primarily to investigate the levels of uric acid, lactate, and neutrophil to lymphocyte ratio (NLR) due to their direct association with the pathogenetic mechanism associated with MS, and the possibility of suggesting them as new parameters in the approach to determine the development and severity of multiple sclerosis. Methods: This case-control study included 80 Syrian individuals of both sexes divided into two groups: patients with multiple sclerosis group (n=40) and control group (n=40) matched in age and sex to the patients group. Uric acid and lactate levels were measured by an enzymatic colorimetric method using the Roche Cobas Uric acid kit (Roche, Germany) and Roche Cobas Lactate kit (Roche, Germany), respectively, while a complete blood count of the samples was performed using ADVIA 2120i Siemens device and the NLR was calculated. The statistical analysis was conducted using SPSS version 25 (SPSS Inc., Chicago, IL, USA). Values were presented as mean ± standard deviation. A P-value < 0.05 was considered to indicate statistical significance. Results: Uric acid levels in MS group were lower than their levels in the control group (P=0.0002), while lactate levels and NLR in MS group were higher than those in the control group (P=0.0001). This study also found that uric acid levels in patients with EDSS>3 were lower than in patients with EDSS≤3 (P=0.0001), while NLR in patients with EDSS>3 was higher than in patients with EDSS≤3 (P=0.0001). Uric acid levels in MS patients undergoing disease attack were lower than in MS patients under remission (P=0.0001), while lactate levels and NLR were higher in MS patients undergoing disease attack than in MS patients under remission (P=0.0001). Conclusions: Our findings indicated that uric acid levels decreased in MS patients, in contrast to lactate levels and NLR, which increased in those patients. These results also showed a relationship between these parameters and MS status expressed by the EDSS score, and the presence or absence of MS attack. Based on our findings, blood levels of uric acid and lactate and NLR are related to MS and can be proposed as new parameters in the approach to determine the development and severity of multiple sclerosis.