Can Borrelia miyamotoi Cause Confusion and Encephalitis?
Confusion and facial numbness may occur with Borrelia miyamotoi
Neurologic symptoms may resemble stroke or Lyme neuroborreliosis
Diagnosis can be challenging when Lyme testing is inconclusive
A 73-year-old man was admitted to the hospital with a 16-day history of confusion and intermittent headaches. He was an avid gardener and reportedly had tick bites in the past but none that he noticed in the weeks prior to his symptoms.
His illness initially resembled a stroke and later appeared consistent with Lyme neuroborreliosis. The underlying diagnosis was Borrelia miyamotoi meningoencephalitis.
Borrelia miyamotoi Can Mimic Stroke
Initially, he developed “right-sided facial droop and associated numbness, confusion, and word-finding difficulties,” the authors write in the article “Borrelia miyamotoi Meningoencephalitis in an Immunocompetent Patient.”1
Neurologic symptoms included facial droop, facial numbness, confusion, excessive fatigue, and word-finding difficulties that initially raised concern for a stroke.
His symptoms, which had improved, were attributed to a mini-stroke.
“Over the next 2 weeks, he continued to feel numbness in his right face and developed worsening confusion, intermittent headaches, and excessive fatigue; he was afebrile throughout this time.”1
Positive Lyme Test but Negative Western Blot
The patient had a positive Lyme enzyme immunoassay (EIA) but a negative Western blot, a diagnostic pattern that prompted clinicians to consider another tick-borne illness. This finding is important because Borrelia miyamotoi infection can sometimes cross-react with Lyme screening tests.
He was “empirically treated with intravenous ceftriaxone for treatment of presumed Lyme meningoencephalitis, and his mental status rapidly improved,” the authors write.
READ MORE: What is Borrelia miyamotoi?
When repeat Lyme testing remained negative by Western blot, clinicians broadened the differential diagnosis to include Borrelia miyamotoi.
Borrelia miyamotoi Meningoencephalitis Diagnosis
The man ultimately tested positive for Borrelia miyamotoi.
The diagnosis explained his progressive neurologic symptoms, including confusion, headaches, facial numbness, and encephalopathy.
The authors emphasized that Borrelia miyamotoi disease should be considered in patients presenting with progressive neurologic symptoms, particularly when Lyme disease testing yields a positive screening test but a negative Western blot.
- “Our case therefore highlights the need to include B. miyamotoi disease in the differential diagnosis for any patient who presents with acute onset, progressive encephalopathy with culture-negative CSF in B. miyamotoi–endemic regions, not just those who are immunocompromised.”
- “Our case highlights the importance of considering B. miyamotoi in clinically suspicious cases of meningoencephalitis, including when B. burgdorferi EIA results are positive but the WB is negative.”
Neurologic Recovery Following Treatment
The man made a “nearly full neurological recovery with only residual intermittent right facial numbness” after anti-Borrelia antibiotic treatment.
This favorable outcome highlights the importance of recognizing Borrelia miyamotoi infection early, particularly when neurologic symptoms continue to worsen despite an unclear diagnosis.
Frequently Asked Questions
Can Borrelia miyamotoi cause confusion?
Yes. Borrelia miyamotoi can affect the central nervous system and may present with confusion, fatigue, headaches, and encephalopathy.
Can Borrelia miyamotoi cause encephalitis?
Although uncommon, Borrelia miyamotoi has been associated with meningoencephalitis and other neurologic complications.
Can Borrelia miyamotoi mimic Lyme disease?
Yes. Patients may have overlapping symptoms and can occasionally test positive on Lyme EIA screening while remaining negative on Lyme Western blot testing.
Can Borrelia miyamotoi mimic a stroke?
Neurologic symptoms such as facial numbness, facial weakness, confusion, and word-finding difficulty may initially resemble a stroke or transient ischemic attack.
Clinical Takeaway
In clinical practice, Borrelia miyamotoi may be overlooked when neurologic symptoms resemble stroke, viral encephalitis, or neurologic Lyme disease.
This case highlights the importance of considering Borrelia miyamotoi infection in patients with confusion, meningoencephalitis, facial numbness, fatigue, or other progressive neurologic symptoms following possible tick exposure.
Clinicians should consider Borrelia miyamotoi when Lyme screening tests are positive but Western blot testing is negative, particularly in patients with progressive neurologic symptoms.
Related Articles
Could Borrelia miyamotoi Infections Explain Persistent Symptoms in Lyme Disease Patients?
Doctors Face Challenges in Diagnosing Borrelia miyamotoi
Blood Smear Not Reliable in Diagnosing Borrelia miyamotoi Disease
Lyme Disease Symptoms Guide
References
- Gandhi S, Narasimhan S, Workineh A, Mamula M, Yoon J, Krause PJ, Farhadian SF. Borrelia miyamotoi meningoencephalitis in an immunocompetent patient. Open Forum Infect Dis. 2022;9(7):ofac295.
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
