Diagnostic and prognostic power of CSF Tau in amyotrophic lateral sclerosis

Journal of Neurology - Amyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease that still lacks reliable diagnostic biomarkers. This study aims to evaluate the diagnostic and...     

CSF markers in amyotrophic lateral sclerosis

Amyotrophic lateral sclerosis (ALS, 'Lou Gehrig disease') is the most common, progressive, neurodegenerative, motor neuron disease, causing damage to upper and lower motor neurons, leading to paralysis and death within 3-5 years. Majority of ALS cases are sporadic ALS (SALS) and only 5-10 % of cases are familial ALS (FALS). Pathogenesis of ALS is complicated and still unclear, including genetic, glutamate excitotoxicity, oxidative stress, mitochondrial dysfunction, neurofilament accumulation, impaired trophic support, altered glial function, viral infection, immune imbalance and impairment of the blood-brain, blood-spinal cord and blood-cerebrospinal fluid barriers (BBB/BSCB/BCSFB). The CSF analysis is still one of the basic laboratory tools and might reflect pathophysiological alterations in the course of the disease and could provide an insight into disease pathomechanisms. The most important aim of its analysis is evaluation of blood-CSF barrier, which is altered in 46 % of ALS patients. The CSF biomarkers may give insight into ALS pathophysiology and may be useful for early, presymptomatic diagnosis, therapeutic monitoring and the development of new therapeutic strategies. This review summarizes the general concepts of biomarkers in CSF of ALS patients and their potential usefulness in further research.     

Ensuring continued progress in biomarkers for amyotrophic lateral sclerosis

Multiple candidate biomarkers for amyotrophic lateral sclerosis (ALS) have emerged across a range of platforms. Replication of results, however, has been absent in all but a few cases, and the range of control samples has been limited. If progress toward clinical translation is to continue, the specific biomarker needs of ALS, which differ from those of other neurodegenerative disorders, as well as the challenges inherent to longitudinal ALS biomarker cohorts, must be understood. Appropriate application of multimodal approaches, international collaboration, presymptomatic studies, and biomarker integration into future therapeutic trials are among the essential priorities going forward. Muscle Nerve 51 : 14–18, 2015     

肌萎缩侧索硬化症脑脊液中生物标记物研究进展

肌萎缩侧索硬化症是一种慢性进展性疾病,目前病因及发病机制不明,尚无有效的生物标志物协助疾病诊断、判断疾病进展及预后。生物标记物研究通过对病理生理机制的探索可以加深对疾病的理解,有助于疾病诊断、分类、药效学检测,及识别新的药物靶点,为新疗法实施提供方向。 [引用格式:国际神经病学神经外科学杂志, 2021, 48(4): 392-395.]     

Diagnostic-prognostic value and electrophysiological correlates of CSF biomarkers of neurodegeneration and neuroinflammation in amyotrophic lateral sclerosis

Journal of Neurology - Neurofilament light chain protein (NfL) is currently the most accurate cerebrospinal fluid (CSF) biomarker in amyotrophic lateral sclerosis (ALS) in terms of both diagnostic...     

Neurofilament levels as biomarkers in asymptomatic and symptomatic familial amyotrophic lateral sclerosis

Neurofilaments are elevated in the cerebrospinal fluid (CSF) and serum of amyotrophic lateral sclerosis (ALS) patients. However, timing of this increase is unknown. To characterize the premanifest disease phase, we performed a cross‐sectional study on asymptomatic (n = 12) and symptomatic (n = 64) ALS mutation carriers and family controls (n = 19). Neurofilaments NF‐L (neurofilament–light chain) and pNF‐H (phosphorylated neurofilament–heavy chain) are normal before symptom onset and increased by at least an order of magnitude at early symptom onset in CSF (pNF‐H) or serum and CSF (NF‐L). Thus, blood and CSF neurofilament levels are linked to the symptomatic phase of ALS and might serve as objective markers of structural damage to the nervous system. ANN NEUROL 2016;79:152–158     

Sequence variants in human neurofilament proteins: Absence of linkage to familial amyotrophic lateral sclerosis

Neurofilaments, assembled from NF-L (68 Kd), NF-M (95 Kd), and NF-H (115 kd), are the most abundatn structural components in large myelinated axons, particularly those of motor neurons. Aberrant neurofilament accumulation in cell bodies and axons of motor neurons is a prominent pathological feature of several motor neuron diseases, including sporadic and familial amyotrophic lateral sclerosis (ALS). Transgenic methods have proved in mice that mutation in or increased expression of neurofilament subunits can be primary causes of motor neuron disease that mimics the neurofilamentous pathology often reported in human disease. To examine whether mutation in neurofilament subunits causes or predisposes to ALS, we used single-strand conformation polymorphism coupled with DNA sequencing to search for mutations in the entirety of the human NF-L, NF-M, and NF-H genes from 100 familial ALS patients known not to carry mutations in superoxide dismutase 1 (SOD1), as well as from 75 sporadic ALS patients. Six polypeptide sequence variants were identified in rod and tail domains of NF-L, NF-M, or NF-H. However, all were found at comparable frequency in DNAs from normal individuals and no variant cosegregated with familial disease. Two deletions found previously in NF-H genes of sporadic ALS patients were not seen in this group of familial or sporadic ALS patiens.     

The diagnostic interval in amyotrophic lateral sclerosis

We studied whether there are any parameters that influence the period between onset of symptoms and confirmation of diagnosis in 117 patients with ALS (65 male, 52 female). The mean age of diagnosis was 57 years for men and 59 years for women. Bulbar-onset patients were older at diagnosis than limb-onset patients both men and women. Patients with bulbar-onset appeared to be more frequent in women (33:19). Contrariwise, limb-onset patients were more frequently male (43:22). The time to confirmation was much shorter with symptoms of bulbar-onset (10.5 months in male, 9.8 months in female) than for those with limb-onset (13.7 months in male, 14.8 months in female) in male, respectively, female ALS patients. The diagnosis of ALS was established in all cases by neurologists in our study.     

Cerebrospinal fluid (CSF) findings in amyotrophic lateral sclerosis

Summary The cerebrospinal fluid (CSF) was examined in 90 amyotrophic lateral sclerosis (ALS) patients and in 50 age-matched normal controls. Total protein concentration was significantly higher in ALS patients than in normal controls. CSF IgG and albumin, quantitatively determined by single radial immunodiffusion, were significantly increased in ALS. No difference in serum concentrations was observed between ALS patients and normal controls. On isoelectric focusing a clear-cut fingerprint pattern was observed in 11 of 12 cases. These findings support the hypothesis that blood-brain barrier damage occurs in ALS. The finding of a higher mononuclear cell count in young ALS patients is briefly discussed in the light of the hypothesis that an exogenous agent might be of some relevance in pathogenesis. An alteration of at least one of the CSF parameters considered was found in 45.5% of ALS cases.

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Zusammenfassung In 90 Fällen von amyotrophischer Lateralsklerose und bei 50 auch im Alter entsprechenden Kontrollen wurde der Liquor untersucht. Der Eiweißgehalt war bei den Patienten mit ALS signifikant höher als bei den Kontrollen. Die Albuminfraktion und das IgG, die mit Immunodiffusionsmethoden quantitativ bestimmt wurden, waren bei der ALS im Liquor signifikant erhöht, während sie sich im Serum gleich wie bei den Kontrollfällen verhielten. Bei der isoelektrischen Fokusierung ließ sich ein eindeutiges Finger-print-pattern in elf von zwölf Fällen beobachten. Diese Befunde sprechen dafür, daß bei der ALS eine Störung der Blut-Hirnschranke vorliegt. Es wird kurz auf die Beobachtung einer vermehrten Zahl mononukleärer Zellen bei jungen Patienten mit ALS eingegangen und im besonderen die Frage diskutiert, in wieweit ein exogenes Agents in der Pathogenese eine Rolle spielen könnte. Mindestens eines der obern erwähnten Parameter war bei 45% aller ALS Fälle im Liquor verändert.

     

Discovery and verification of amyotrophic lateral sclerosis biomarkers by proteomics

Recent studies using mass spectrometry have discovered candidate biomarkers for amyotrophic lateral sclerosis (ALS). However, those studies utilized small numbers of ALS and control subjects. Additional studies using larger subject cohorts are required to verify these candidate biomarkers. Cerebrospinal fluid (CSF) samples from 100 patients with ALS, 100 disease control, and 41 healthy control subjects were examined by mass spectrometry. Sixty‐one mass spectral peaks exhibited altered levels between ALS and controls. Mass peaks for cystatin C and transthyretin were reduced in ALS, whereas mass peaks for posttranslational modified transthyretin and C‐reactive protein (CRP) were increased. CRP levels were 5.84 ± 1.01 ng/ml for controls and 11.24 ± 1.52 ng/ml for ALS subjects, as determined by enzyme‐linked immunoassay. This study verified prior mass spectrometry results for cystatin C and transthyretin in ALS. CRP levels were increased in the CSF of ALS patients, and cystatin C level correlated with survival in patients with limb‐onset disease. Our biomarker panel predicted ALS with an overall accuracy of 82%. Muscle Nerve 42: 104–111, 2010     

Muscle ultrasonography: a diagnostic tool for amyotrophic lateral sclerosis

ObjectiveIn a prospective study we tested whether muscle ultrasonography can differentiate between amyotrophic lateral sclerosis (ALS) and mimics. Furthermore, we assessed the ability of ultrasonography to identify subclinical lower motor neuron involvement.MethodsIn 59 patients, suspected for adult onset motor neuron disease, ultrasound scans were made of 12 different muscle groups. Echo intensity was determined and each muscle was screened for fasciculations. Ultrasonography was considered diagnostic for ALS when echo intensity was 1.5 SD above normal in at least two muscles and fasciculations were present in at least four muscles.ResultsUltrasonography differentiated between ALS and mimics with 96% sensitivity and 84% specificity. In the 27 ALS patients, ultrasonography detected 15 regions with lower motor neuron involvement that were negative using either clinical examination or needle EMG.ConclusionsMuscle ultrasound can differentiate between amyotrophic lateral sclerosis and mimics with high sensitivity and specificity, and is a sensitive tool to screen for regional lower motor neuron involvement.SignificanceMuscle ultrasonography is a promising tool in the diagnostic work up of ALS.     

ITIH4 and Gpx3 are potential biomarkers for amyotrophic lateral sclerosis

The diagnosis of amyotrophic lateral sclerosis (ALS) is difficult due to lack of definitive biomarkers. Our aim was to identify characteristic serum protein patterns that could provide candidate biomarkers for ALS. We divided mutant superoxide dismutase-1 (SOD1)^H46R rats into three groups based on disease progression: pre-symptom (90 days), onset, and end-stage. After separation of serum proteins using two-dimensional electrophoresis, we selected clear protein spots and identified two candidate proteins—inter-alpha-trypsin inhibitor heavy chain H4 (ITIH4) and glutathione peroxidase 3 (Gpx3). The 120 kDa ITIH4 increased at the onset of the disease and the 85 kDa ITIH4, a cleaved form, at the end-stage in the sera of the SOD1^H46R rats. Expression of the 85 kDa ITIH4 was substantial in ALS compared with controls or patients with muscular dystrophy, Alzheimer diseases, or Parkinson diseases. The Gpx3 protein levels in the sera of SOD1^H46R rats were upregulated pre-symptom and gradually decreased as the disease progressed. The Gpx3 protein levels were lower in the sera of the patients with ALS than in other diseases. These results indicate that ITIH4 and Gpx3 are potential biomarkers for ALS.     

Evaluation of arterial blood gas parameters as prognostic markers in amyotrophic lateral sclerosis

Background

Forced vital capacity (FVC) remains difficult to determine for some patients suffering from amyotrophic lateral sclerosis (ALS) due to the rapid progression of the disease. Arterial blood gas (ABG) parameters could represent a valuable alternative. The aim of this study was therefore to evaluate the correlation between ABG parameters and FVC, along with the prognostic ability of ABG parameters, in a large cohort of ALS patients.

Methods

ALS patients (n=302) with FVC and ABG parameters available at diagnosis were included. Correlations between ABG parameters and FVC were evaluated. Cox regression was then carried out to determine the association of each parameter (ABG and clinical data) with survival. Finally, receiver operating characteristic (ROC) curves were built to predict the survival of ALS.

Results

Bicarbonates (HCO₃⁻), oxygen partial pressure (pO₂), carbon dioxide partial pressure (pCO₂), base excess (BE), oxygen saturation and oxyhemoglobin were significantly correlated with FVC both in patients with spinal or bulbar onset. Univariate Cox regression showed that HCO₃⁻ and BE were associated with survival but only in spinal forms. ABG parameters predicted the survival of ALS with a similar performance to FVC, HCO₃⁻ being the parameter with the highest area under the curve.

Conclusions

Our results suggest that there is an interest in conducting a longitudinal evaluation throughout disease progression to confirm the equal performances of FVC and ABG. This study highlights the benefits of performing ABG analysis that could be used as an interesting alternative to FVC when spirometry cannot be performed.     

Serum neurofilament light chain cut-off definition for clinical diagnosis and prognosis of amyotrophic lateral sclerosis

Background

The neurofilament light chain (NfL) assay is gradually becoming an essential diagnostic tool for the diagnosis of many neurological diseases including amyotrophic lateral sclerosis (ALS). Different methods for the determination of this biomarker in serum have been developed in recent years.

Methods

We measured blood NfL in 429 patients referred to the tertiary ALS center of Montpellier, France using two different ultrasensitive methods (Ella™ and Simoa™) and we compared the clinical performances of these two approaches. We also converted NfL values into age and body mass index-adjusted Z-scores to assess cut-off values of this biomarker in this clinical context.

Results

We show comparable diagnostic and prognostic performance of Ella™ and Simoa™ technologies in ALS, with specificities and sensitivities exceeding 80% for both. We propose cut-off values for serum NfL in this clinical context, thus enabling the routine clinical use of this biomarker.

Conclusion

The use of NfL in routine clinical practice will help predict survival and improve diagnostic accuracy by distinguishing ALS from other neurological diseases and motor neuron disease mimics.