The Diagnostic Value of Ubiquitin C‐Terminal Hydrolase L1 (UCH-L1) and Progranulin (PGRN) Markers Compared to Some of the Traditional Laboratory Markers in Spinal Cord Injury: A Case-Control Study

Background: Spinal cord injury (SCI) is considered one of the most functionally and clinically devastating traumatic neurological injuries, and there is still a need to have blood biomarkers that can be used to aid in early evaluation and enhance diagnostic distinction. Ubiquitin C-Terminal Hydrolase L1 (UCH-L1) is a neurogenic injury marker and progranulin (PGRN) is an inflammatory, cell survival, and neural repair molecule. Objective: The objective of the study was to assess the diagnostic usefulness of both UCH-L1 and PGRN in patients with spinal cord injury, and compare them with a healthy control group, and their correlation with common clinical and laboratory markers. Methods: The study was conducted using a case-control design and included 120 participants: 60 patients with spinal cord injury and 60 controls. UCH-L1 and PGRN were measured by ELISA, along with a number of routine laboratory variables. Medians and interquartile ranges were used to present the data, the Mann-Whitney U test for comparisons between the two groups, and ROC analysis to assess diagnostic performance, with a statistical significance level of   <0.05. Results: No statistically significant differences were observed between the two groups regarding age and body mass index (p=0.07 and p=0.087, respectively), supporting the similarity of baseline characteristics. In contrast, patients showed marked increases in CK, LDH, CRP, WBC, and glucose, along with a significant decrease in Hb, all with high statistical significance (p<0.001). PGRN was also significantly elevated in patients compared to controls (203.76 vs. 113.8, p<0.001), as was UCH-L1 (86.4 vs. 39.7, p<0.001). The severity distribution showed that 78.3% of cases were in the severe category. In the correlation analysis, a strong positive correlation was observed between UCH-L1 and CK (rho = 0.900, p = 0.04), while the relationship between PGRN and CRP was marginally significant (rho = 0.890, p = 0.05). The ROC analysis showed that PGRN had the highest discriminatory power (AUC=0.99, sensitivity 0.93, specificity 1.00, at a cutoff of 158.1), followed by LDH (AUC=0.97) and then UCH-L1 (AUC=0.957), with WBC, CRP, and CK also performing well. Conclusions: The analysis shows a unique blood profile of spinal cord injury that is a combination of neuropathic injury, inflammatory, and tissue damage markers. PGRN was the most promising exploratory biomarker to differentiate between patients and healthy controls in this sample, and UCH-L1 was found to have high diagnostic value that is more directly related to the neuropathic injury component. The findings indicate that a multi-marker diagnostic method can be more practical compared to the use of a single marker, especially in the initial evaluation of cases.