Unexplained Stroke: Look for Lyme Disease
Lyme disease should be considered in patients with unexplained stroke—especially when standard risk factors are absent.
Moreno Legast and colleagues describe the case of an 83-year-old man in whom Lyme neuroborreliosis was strongly suspected as the cause of stroke.
Stroke Without a Clear Cause
The patient presented with right-sided weakness and speech difficulties that developed over 24 hours.
Brain imaging revealed ischemic lesions, but there was no evidence of:
- Hypertension
- Large vessel disease
- Cardiac embolic source
This prompted further investigation into less common causes.
A Clue: Antiphospholipid Antibodies
The patient tested positive for a lupus anticoagulant—an antibody sometimes associated with clotting disorders and infections.
Antiphospholipid antibodies have been reported in Lyme disease.
This finding led clinicians to expand the diagnostic workup.
Lyme Disease Confirmed
Serologic testing for Lyme disease (ELISA and Western blot) was positive.
Further history revealed multiple prior tick bites and a history of paresthesias years earlier—suggestive of earlier neurologic involvement.
A spinal tap showed:
- Elevated protein
- Increased CSF/serum Lyme IgG antibody index
- No pleocytosis
The findings were consistent with possible Lyme neuroborreliosis.
Treatment and Outcome
The patient was treated with intravenous ceftriaxone for 14 days.
Antiphospholipid antibodies normalized within 6 weeks.
He improved clinically but was left with residual right arm weakness.
This highlights the potential for long-term neurologic sequelae.
Why This Case Matters
This case illustrates several important points:
- Lyme disease can present without rash or classic early symptoms
- Neurologic Lyme may precede stroke by months or years
- Standard stroke evaluations may miss infectious causes
Failure to consider Lyme disease may delay diagnosis and treatment.
Clinical Takeaway
In patients with unexplained stroke—particularly without traditional vascular risk factors—Lyme disease should be included in the differential diagnosis. Early recognition may improve outcomes and prevent further neurologic damage.
Dr. Daniel Cameron, MD, MPH
Lyme disease clinician with over 30 years of experience and past president of ILADS.
Symptoms • Testing • Coinfections • Recovery • Pediatric • Prevention
I used to take out around 10-20 ticks off of my head, every “weekend” in Old Saybrook/Old Lyme, CT, when I was the age of 10-16. Although, I’ve been active (sports) all my life, I have also Been sick all my life and no professional one knew why. I suffer from headaches/migraines all my life and no professional one knew why. I was finally diagnosed with Chronic Lyme in 1996. Treated with plaquenil and doxycycline.
As of 2016, I am on disability due to a stroke/endarterectomy, and no professional one knows why. What a life!,,
Have you looked a second time at whether retreatment or treatment of a co-infection might help?
I had just turned 40 and was having a hard year after losing someone close to me. I started to get I’ll. Headaches at first then migraine. Many time I found myself in hospital for a few days. No doctor had a clue but I got better and went home. At Christmas that same year I had a stroke. With much therapy I was able to go home. In the new year i still didn’t feel well but i thought i was depressed because of the stroke. Around April i went to see an eye doctor because I thought the stroke had weekend by sight. She sent me straight back to the doctor in the hospital the next day. He was able to reassure me that I was fine. This was confusing for me because I didn’t feel fine. 3 weeks later I went back to the same eye doctor who called an ambulance and had me taken to a specialist eye hospital. I then spent nearly 3 weeks in intensive care while I was tested for all number of things. My brain was swollen putting pressure on my eyes. Couldn’t move of the bed for weeks and for a few weeks after that I was in a wheelchair. Then they told me that they believed it to be limes disease. I am left feeling very week quickly and have trouble remembering stupid things and some rather important things but that was 7 years ago and I am still here.
How frustrating. I am glad you are still there.