Neurologic Complications of Babesia
Babesia may affect more than red blood cells
Neurologic symptoms were common in hospitalized patients
Higher parasitemia may increase symptom severity
In their study, “Neurologic Complications of Babesiosis,” the authors sought to describe the type and frequency of neurologic complications in hospitalized patients with babesiosis and assess risk factors that might predispose patients to neurologic complications.1
Locke and colleagues examined the medical records of 163 patients admitted to Yale-New Haven Hospital in New Haven, Connecticut between January 2011 and October 2021 with laboratory-confirmed babesiosis. The patients either had Babesia parasites on blood smear or amplification of B. microti DNA by PCR.
More than half of the 163 patients experienced one or more neurologic symptoms during hospitalization. Neurologic symptoms were associated with high-grade parasitemia, renal failure, and diabetes mellitus.1
What neurological symptoms occurred with Babesia?
The most frequent symptoms were headache, confusion or delirium, impaired consciousness, ataxia or gait disorder, and vision impairment. Three patients were obtunded and one patient was stuporous.
Patients with the highest parasitemia levels were more likely to experience confusion.1
Ten patients reported transient vision changes. One patient was evaluated by an ophthalmologist after seeing colored lights and shapes when closing her eyes despite having a normal ophthalmologic examination.
How severe were these neurologic complications?
Over half (59.5%) of the patients were admitted to the intensive care unit and four patients died.1
These findings suggest neurologic complications may be more common in severe babesiosis than previously appreciated.
Patients with Babesia are sometimes assumed to be asymptomatic after treatment. However, most patients had cleared or improved neurologic symptoms by discharge, leaving open questions regarding long-term recovery.1
The severity and duration of symptomatic cases remain uncertain. As Locke points out, “The duration of symptoms after discharge is unknown.”1
Notably, the authors did not describe whether other tick-borne illnesses contributed to symptoms, nor did they describe treatment approaches for their patients.
Because symptoms such as dizziness, gait problems, confusion, and visual changes overlap with other tick-borne illnesses, clinicians evaluating persistent symptoms may also review related conditions involving Babesia, coinfections, and neurologic Lyme disease.
Why might Babesia affect the nervous system?
The study did not establish why neurologic complications occur. However, patients with higher parasitemia levels and greater illness severity were more likely to develop symptoms, suggesting that infection burden and systemic illness may contribute.1
Frequently Asked Questions
Can Babesia cause neurological symptoms?
Yes. Reported symptoms included confusion, delirium, headache, gait abnormalities, impaired consciousness, and visual symptoms.1
What neurological symptoms are most common with Babesia?
Headache, confusion, altered mental status, gait problems, and vision changes were among the most commonly reported neurologic findings.
Can Babesia affect vision?
Yes. Some patients reported transient vision changes, including seeing lights or shapes, despite normal ophthalmologic examinations.1
What is cerebral babesiosis?
Cerebral babesiosis generally refers to severe neurologic involvement associated with Babesia infection, though definitions vary and this study evaluated a broad spectrum of neurologic complications rather than isolated cerebral disease.
Clinical Takeaway
Babesia neurological symptoms may be more common than previously appreciated in severe disease.
Confusion, gait changes, altered consciousness, and visual symptoms should prompt clinicians to consider neurologic complications in patients with significant babesiosis.
Related Articles
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Wide range of Babesia symptoms and presentations
Autonomic dysfunction and neurologic symptoms
Mechanisms of persistent symptoms
References
- Locke S, et al. Neurologic Complications of Babesiosis, United States, 2011–2021. Emerging Infectious Diseases. 2023;29(6).
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
