Belgian researchers say measuring neurofilaments could help to confirm the presence of amyotrophic lateral sclerosis (ALS) more quickly.

Currently, ALS can be difficult to definitively diagnose, especially at its onset. Researchers at the Flanders Interuniversity Institute for Biotechnology in Belgium noted in a news announcement that ALS often takes a year to diagnose — a critically long time for a disease with a life expectancy of just two to five years after first symptoms are seen.

Flanders Interuniversity Institute researchers, along with colleagues at the University of Jena in Germany, now say that measuring a patient’s neurofilaments could help to confirm an ALS diagnosis.

In the research news announcement, Philip Van Damme, professor at Flanders Interuniversity Institute and one of the researchers involved in the study, said, “Despite the severity of the disease, an ALS diagnosis relies heavily on the physician’s clinical acuity. The typical disease progression of ALS, with the loss of strength extending from one body region to another, allows a definite diagnosis. In the early stages of the disease, diagnosis is difficult. Consequently, the average time between the first symptoms and diagnosis is approximately one year. Better tests are needed for a faster ALS diagnosis, which we hope to achieve with this test.”

Researchers explained that neurofilaments are “structural proteins in the cytoskeleton, which are present in high concentrations in motor neurons. It has been known for a long time that the lumbar fluid in ALS patients contains a higher concentration of neurofilaments, perhaps because they are released from sick motor neurons.”

Koen Poesen, professor at the University of Leuven in Belgium, said, “We have demonstrated that a certain type of neurofilament (pNfH, phosphorylated neurofilament heavy) in particular increases sharply in the lumbar fluid of ALS patients. This is even true when compared to patients presenting loss of strength symptoms due to other conditions (known as ALS mimics). The test meets all the requirements for use as a reliable diagnostic test. However, it requires an epidural because we can still only reliably measure the neurofilaments in the lumbar fluid.”