Biomarkers are objective measures that scientists, researchers, and doctors can use to understand what is going on in your body. For example, your blood pressure can tell doctors about your health; your complete blood count can signify if something is “off.” Researchers from the University of Alberta recently identified a novel and universal biomarker that could be used to diagnose myasthenia gravis.
Fibrinogen: A Puzzle Piece
Gillian Rutherford reports in Folio that the University of Alberta team, headed by principal investigator Zaeem Siddiqi, sought out to improve the diagnostic process for this rare condition. Currently, pursuing a myasthenia gravis diagnosis is difficult. Muscle weakness is characteristic of many conditions and there are no myasthenia gravis-specific tests. Instead, patients must undergo EMGs, blood tests, and other exams prior to getting a diagnosis; some doctors even recommend starting treatment, with the diagnosis being confirmed if/when the patient responds.
Additionally, blood tests often underdiagnose myasthenia gravis. Some individuals with myasthenia gravis don’t develop antibodies. As a result, blood tests may show a false negative in anywhere from 15-50% of individuals. Identifying this biomarker could potentially improve the diagnostic process and get answers to patients more quickly.
The research team began by collecting blood samples from 79 individuals. Of these, 31 had myasthenia gravis, 18 had rheumatoid arthritis, and 30 were healthy. In research published in Scientific Reports, the investigators detail how they used proteomic analysis and antibody-based testing to evaluate blood proteins. They found that people with myasthenia gravis had fibrinogen levels that were 1,000x higher than the other two groups. These findings were replicated even in blind samples and analyses. Learn more about fibrinogen here.
As it stands, fibrinogen could stand as a biomarker for myasthenia gravis, as well as treatment response. But it is important to note that researchers are still unclear as to how and why increased fibrinogen might play a role in myasthenia gravis, or if these results are replicable in larger patient populations. More research is underway to confirm.
About Myasthenia Gravis (MG)
Grave muscle weakness: when you unpack what “myasthenia gravis” really means, you see that this rare autoimmune neuromuscular disorder is aptly named.
Myasthenia gravis occurs when the body’s antibodies mistakenly attack certain muscle receptors that receive nerve impulses. This makes it more difficult for the muscles to read nerve signals, so the muscles weaken and don’t respond as well. This condition normally manifests in adulthood, although symptoms may appear at any age. Symptoms may include:
- Muscle weakness and fatigue in the skeletal muscles (arms, legs, eyes, mouth, throat)
- Double vision
- Drooping eyelids
- Speech impairments, such as slurred speech or a weak, hoarse, and/or nasally voice
- Difficulty chewing and/or swallowing (dysphagia)
- Aspiration
- Changed gait
- Neck or limb weakness
Symptoms often worsen with activity and improve with rest. Treatments like plasmapheresis, thymus gland removal, or steroids may also improve symptoms. However, some individuals remain refractory to treatment options. 10% of patients also develop life-threatening respiratory complications, requiring additional respiratory support.
