Correlation between neuropathic pain and serum lysophosphatidic acid and s100 beta protein levels in patients with spinal cord injury

Objective: In this study, we aimed to evaluate relation between neuropatic pain with serum lysophosphaditic acid (LPA) and S100B protein levels and detect its utility as a biomarker in patients with traumatic spinal cord injury (SCI). Materials and Methods: We included total of 177 patients with traumatic spinal cord injury to the study. Demographical data of the patient group were recorded. Physical examinations of the patients were performed via using ASIA evlauation form. DN4 scale was used for evaluation of neuropathic pain of the included patients. The patients were divided into two groups as patients with neuropathic pain (n=101) and without neuropathic pain (n=76). Intensity of neurological pain symptomes (burning, tingeling, numbness, pricking, chill sensation, itching, blunt pain, paroxismal pain, superficial pain, deep pain and unpleasentness) was evaluated by VAS. Life quality level of the patients were evlauated with SF-36 form, depression level with Beck Depression Scale (BDS), functional independence level with Functional Independence Measure (FIM), functional ambulation level with WISCI, and spacity with Modified Ashwrth Scale. Blood samples were taken from the patients for measuring serum LPA and S100B protein level. Serum LPA and S100B measurements were performed via using Bioassay Technology Laboratory Human S100B and Lysophosphatidic Acid Elisa kits. For evaluation of LPA and S100B protein levels, concommitant hematological and biochemistrical parameters which are being used for routine assesment of the patients were ordered and results were recorded. Data were evaluated with SPSS 22.0 package program. For all the results, p value of <0.05 considered statistically significant. Results: In our study including two patient group as with nerophatic pain (n=101) and without neuropathic pain (n=76), no significant demographical difference were detected between groups except BMI. Mean RMI level was significantly higher in patients with neuropathic pain. There was no statistically significant difference between groups regarding injury time or ethiology, neurological condition and injured spinal area. General body pain, emotional role disability, mental health, and liveliness subparameters of SF-36 form were significantly lower in patient group with neuropathic pain. BDS was significantly higher in patient group with neuropathic pain. Patients were evaluated for functional independency level and no significant difference detected FIM total motor scor between the groups. When ambulation levels were evaluated, no significant difference between groups regarding WISCI level was detected. When relations of serum LPA and S100B levels with age and BMI of the patients, significant negative correlation with age and BMI was detected. Relations of serum LPA and S100B protein levels with biochemistircal and hematological parameters were investigated and statsitcally significant negative correlation with trigliceride and glucose levels and positive correlation with HDL levels were detected. When relations of serum LPA and S100B were evaluated, significant positive correlation was detected. No significant difference was detected when comparing serum LPA and S100B values between SCI patients with and without neuropathic pain. When correlations between serum LPA and S100B levels with DN4 scale used for evaluating neuropathic pain in patients were investigated, no significant correlation was detected. Neuropathic pain symptomes and serum LPA and S100B values were compared and no significant correlation was found. Conclusion: There was no significant relation in comparison of neuropathic pain with LPA and S100B protein levels in patients with SCI. To our knowledge, since there was no other study investigating relations of neuropathic pain with serum LPA and S100B levels in patients with SCI, further research in this area is required. We believe that, CSF (Cerebrospinal Fluid) sampling may reveal more accurate results when investigating relations between neuropathic pain and biomarkers in patients with SCI.