Spinal Fluid Protein Levels Useful In ALS Diagnosis

Cancer can be diagnosed with a biopsy, brain changes that point to multiple sclerosis can be seen on an MRI scan, and the course of many muscle disorders can be tracked by blood levels of the enzyme creatine kinase.

But amyotrophic lateral sclerosis (ALS) doesn’t have these clear biological markers (“biomarkers”) of disease, which are useful not only to diagnose a condition but as indicators of whether or not a treatment is working.

Neurologist Merit Cudkowicz, an MDA research grantee at Massachusetts General Hospital, and Robert Brown, who directs the MDA/ALS Center at MGH, were part of a multi-institutional group that recently identified three spinal fluid proteins for which levels are lower than normal in ALS. The team published its results online Feb. 15 in Neurology.

These three proteins — cystatin C, VGF (not VEGF) and a third identified so far only by its weight — were lower in concentration in the ALS patients’ spinal fluid samples than in samples from unaffected study participants.

“Ultimately, we want to initiate treatments for ALS as early as possible,” Cudkowicz said. “Finding biomarkers that can assist physicians with diagnosis would be beneficial. Biomarkers are also important to help understand disease mechanisms and potential treatment pathway targets, and could also potentially help expedite clinical trials by providing ... outcome measures,” she said, adding that the results need to be replicated by others and in larger sample sizes.