Skip to content

    Stroke Health Center

    Font Size

    Blood Test May Help Spot Stroke

    In Study, Blood Test Identified 98% of People Who'd Had Ischemic Stroke
    WebMD Health News
    Reviewed by Laura J. Martin, MD

    Sept. 29, 2011 (San Diego) -- A new blood test shows promise for helping to detect stroke.

    In a preliminary study of 152 people, the test correctly identified 98% of those who had had an ischemic stroke and 86% of those who hadn't had one. Ischemic stroke is the most common type of stroke. It occurs when a clot blocks blood flow in the brain.

    The test measures levels of a brain chemical called glutamate. When blood flow to the brain is impaired, glutamate is rapidly released into the bloodstream, says researcher Kerstin Bettermann, MD, PhD, associate professor of neurology at Penn State College of Medicine in Hershey.

    The findings were presented here at the annual meeting of the American Neurological Association.

    Imaging Scans Used to Diagnose Stroke

    Each year, more than 750,000 Americans have a stroke. About 80% are ischemic strokes. The rest are hemorrhagic stroke, caused by bleeding in the brain.

    Currently, there is no blood test for detecting stroke, although several groups are developing them.

    When a person arrives at the hospital emergency room with stroke symptoms, a CT or MRI scan of the head is used to help doctors determine if a stroke is in progress and if the person is a candidate for clot-busting drugs.

    But a CT scan doesn't always produce a clear enough image of what is going on in the brain, Bettermann tells WebMD. "An MRI is what is needed, but not all medical centers have them. And some patients can’t have an MRI -- if they have a pacemaker or are claustrophobic, for example."

    That's where the blood test comes in, which Bettermann estimates would only cost about $20.

    It wouldn't replace imaging tests and doctor exams, she says, but used as an add-on to standard tests, it would improve diagnosis.

    Glutamate Levels Rise in Stroke Patients

    The new study included 50 people with ischemic stroke and 102 people without stroke. In the group without stroke, 48 people had stroke risk factors such as diabetes or high blood pressure but no history of stroke, 28 people had stroke-like symptoms such as weakness on one side of the body but were not having a stroke, and 26 were healthy.

    Today on WebMD

    brain illustration stroke
    Know these 5 signs.
    brain scans
    Test your stroke smarts.
    woman with migraine
    Is there a link?
    brain scan
    Get the facts.
    brain scans
    woman with migraine
    brain scan
    senior man stretching pre workout
    Floor level view of therapist helping stroke patie
    concerned woman
    Lowering Cholesterol Slideshow