January 16, 2024

Newly identified biomarker could lead to simple blood test for rare autoimmune disease

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(Photo: Supplied)

A University of Alberta team has uncovered a universal biological marker for myasthenia gravis with the aim of developing a simple, fast and accessible diagnostic test for the rare autoimmune disease.

Affecting one in 5,000 people of all ages, but mostly women under 40 or men over 60, myasthenia gravis means “severe muscle weakness.” Patients may experience drooping eyelids, double vision, difficulty speaking, chewing, breathing and controlling their limbs, and in rare, severe cases the condition can be fatal.

In newly published research, the team used advanced proteomics techniques and discovered blood levels of the protein fibrinogen in myasthenia gravis patients at 1,000 times the level found in both healthy controls and patients who have rheumatoid arthritis, another autoimmune disorder.

“This is a serious disease where you see the patient getting worse in front of your eyes, so we want to have rapid and early diagnosis,” says principal investigator and neurologist Zaeem Siddiqi, who treats patients from Alberta and northern Canada.

Current blood tests for the disease assess one of three antibodies and can take several weeks to get results. Depending on the type of disease the tests may be negative in 15 to 50 per cent of patients who have myasthenia gravis but no antibodies. The symptoms of myasthenia gravis can be confused with other neurological conditions such as stroke or multiple sclerosis so, on average, an accurate diagnosis may take up to two years, Siddiqi says.

Read the full article on Folio