Cerebrospinal fluid biomarkers of white matter injury and astrogliosis are associated with the severity and surgical outcome of degenerative cervical spondylotic myelopathy

Peripheral blood RNA biomarkers can predict lesion severity in degenerative cervical myelopathy

JOURNAL/nrgr/04.03/01300535-202506000-00027/figure1/v/2024-08-05T133530Z/r/image-tiff Degenerative cervical myelopathy is a common cause of spinal cord injury, with longer symptom duration and higher myelopathy severity indicating a worse prognosis. While numerous studies have investigated serological biomarkers for acute spinal cord injury, few studies have explored such biomarkers for diagnosing degenerative cervical myelopathy. This study involved 30 patients with degenerative cervical myelopathy (51.3 ± 7.3 years old, 12 women and 18 men), seven healthy controls (25.7 ± 1.7 years old, one woman and six men), and nine patients with cervical spondylotic radiculopathy (51.9 ± 8.6 years old, three women and six men). Analysis of blood samples from the three groups showed clear differences in transcriptomic characteristics. Enrichment analysis identified 128 differentially expressed genes that were enriched in patients with neurological disabilities. Using least absolute shrinkage and selection operator analysis, we constructed a five-gene model (TBCD, TPM2, PNKD, EIF4G2, and AP5Z1) to diagnose degenerative cervical myelopathy with an accuracy of 93.5%. One-gene models (TCAP and SDHA) identified mild and severe degenerative cervical myelopathy with accuracies of 83.3% and 76.7%, respectively. Signatures of two immune cell types (memory B cells and memory-activated CD4+ T cells) predicted levels of lesions in degenerative cervical myelopathy with 80% accuracy. Our results suggest that peripheral blood RNA biomarkers could be used to predict lesion severity in degenerative cervical myelopathy.

Fluid biomarkers for cervical spondylotic myelopathy

INTRODUCTION

There is a scarcity of literature exploring fluid-based biomarkers that have the potential to provide deeper insights into the cellular mechanisms underlying cervical spondylotic myelopathy (CSM) symptom presentation and postoperative recovery. This systematic review synthesized the literature on invasive, fluid-based biomarkers and their clinical significance with CSM.

MATERIALS AND METHODS

A comprehensive search strategy was developed for concepts of biomarkers and CSM. Retrieved results underwent title, abstract, and full-text screening with inclusion criteria being original research including animal or human subjects affected by CSM/compression myelopathy that investigated the relationship between a fluid-based biomarker and CSM. Risk-of-bias was reported using the OHAT Risk of Bias Rating Tool.

RESULTS

The search strategy resulted in 191 unique manuscripts, with 20 meeting the predetermined inclusion/exclusion criteria, included in final analysis. Of these, 15 (75.0%) were human studies, two (10.0%) were animal studies, and three studies (15.0%) included both human and animal subjects. Across human studies, the fluid utilized for biomarker assessment was blood, (N = 8, 44.4%), cerebrospinal fluid (CSF) (N = 9, 50.0%), and both blood and CSF (N = 1, 5.6%). The three most common biomarkers assessed across human studies were NSE (N = 4, 22.2%), S100b (N = 4, 22.2%), and pNF-H (N = 4, 22.2%). Risk of bias due to inadequate comparison groups was present in three human studies (16.7%) and two animal studies (40%).

CONCLUSIONS

This comprehensive systematic review identified several associations between blood and CSF-based neural, glial, and inflammatory biomarkers and CSM. However, the vast heterogeneity across studies renders it difficult to draw definitive conclusions. Future research within larger, prospective patient cohorts is needed to fully elucidate the utility these biomarkers may hold in the clinical evaluation of patients with CSM.

Noninvasive Skin Autofluorescence of Advanced Glycation End Products in Patients with Degenerative Cervical Myelopathy

OBJECTIVE

To clarify the association between skin autofluorescence of advanced glycation end products (AGEs) and clinical outcomes and pain in patients with degenerative cervical myelopathy (DCM).

METHODS

Consecutive patients with DCM were prospectively enrolled. AGEs assessed by skin autofluorescence (the AGE score) were examined at the middle fingertip in eligible patients. Patients were divided into lower AGE score (AGE-L) and higher AGE score (AGE-H) groups based on a cutoff AGE score of 0.54. Demographic data, laboratory data, maximum spinal cord compression, clinical outcomes, such as European Quality of Life-5 Dimensions, Neck Disability Index, and Japanese Orthopaedic Association score, and Numerical Rating Scale (NRS) score for neck, arm, hand, leg, and foot pain were compared between the two groups. Multiple linear regression analysis was performed to assess the association between the AGE score and the NRS score for pain in the lower limbs.

RESULTS

Of the 263 patients, 93 were included in this study (41 with the AGE-L group and 52 with the AGE-H group). Demographic data, laboratory data, maximum spinal cord compression, and clinical outcomes were comparable between the two groups. The AGE-H group had significantly higher NRS scores for leg and foot pain than the AGE-L group. Multiple linear regression analysis revealed that higher AGE scores were significantly associated with more severe pain in the lower limbs in patients with DCM.

CONCLUSIONS

Noninvasive skin autofluorescence of AGEs may be a useful biomarker for pain symptoms in the lower limbs in patients with DCM.

Application of Short T1 Inversion Recovery Sequence in Increased Signal Intensity Following Cervical Spondylotic Myelopathy

OBJECTIVES

To compare magnetic resonance (MR) short T1 inversion recovery (STIR) sequence with MR T2-weighted (T2W) sequence for detecting increased signal intensity (ISI) and assessing outcomes of ISI in cervical spondylotic myelopathy (CSM).

METHODS

Data of patients with CSM who showed ISI on MR imaging and had undergone cervical spine surgery were retrospectively reviewed. STIR and T2W images were examined to assess signal intensity ratio (SIR), length and grading of the ISI, maximal spinal cord compression, canal narrowing ratio, and ligamentum flavum hypertrophy. The patients were divided into good and poor groups based on their outcomes. χ2 tests and variance analysis were used to assess intergroup differences. Univariate and multivariate logistic regression analyses were performed to identify risk factors for poor outcomes, and receiver operating characteristic curves were plotted to detect prognostic effects.

RESULTS

SIR and ISI lengths were significantly different between the STIR and T2 images. In the univariate logistic regression analysis, age, diabetes, SIRT2, SIRSTIR, and ISISTIR grading were significant factors. Accordingly, in the multivariate logistic regression analysis, age, diabetes, SIRT2, and SIRSTIR were included in the model. Among patients with diabetes, we observed a significant difference between SIRT2 and SIRSTIR.

CONCLUSIONS

The STIR sequence demonstrated superior capability to the T2W sequence in detecting ISI; however, there was no obvious difference in predicted outcomes. STIR sequence has a better prognostic value than T2W sequence in patients with diabetes who have CSM. ISI grading based on the STIR sequence may be a clinically valuable indicator.

A future blood test for acute traumatic spinal cord injury

Acute spinal cord injury (SCI) requires prompt diagnosis and intervention to minimize the risk of permanent neurologic deficit. Presently, SCI diagnosis and interventional planning rely on magnetic resonance imaging (MRI), which is not always available or feasible for severely injured patients. Detection of disease-specific biomarkers in biofluids via liquid biopsy may provide a more accessible and objective means of evaluating patients with suspected SCI. Cell-free DNA, which has been used for diagnosing and monitoring oncologic disease, may detect damage to spinal cord neurons via tissue-specific methylation patterns. Other types of biomarkers, including proteins and RNA species, have also been found to reflect neuronal injury and may be included as part of a multi-analyte assay to improve liquid biopsy performance. The feasibility of implementing liquid biopsy into current practices of SCI management is supported by the relative ease of blood sample collection as well as recent advancements in droplet digital polymerase chain reaction technology. In this review, we detail the current landscape of biofluid biomarkers for acute SCI and propose a framework for the incorporation of a putative blood test into the clinical management of SCI.