Babesia neurologic complications are more common than many clinicians realize. In their study “Neurologic Complications of Babesiosis,” the authors “sought to describe the type and frequency of neurologic complications of babesiosis in a group of hospitalized patients and assess risk factors that might predispose patients to neurologic complications.”
They examined the medical records of 163 patients admitted to Yale-New Haven Hospital in New Haven, Connecticut during January 2011 – October 2021 with laboratory-confirmed babesiosis. The patients either had Babesia parasites on their blood smear or amplification of B. microti DNA by PCR.
Babesia Neurologic Symptoms: Key Findings
“More than half of the 163 patients experienced more than one neurologic symptom during their hospital admissions,” wrote Locke and colleagues.
They found that neurologic symptoms were associated with high-grade parasitemia, renal failure, and history of diabetes mellitus.
The most frequent symptoms were:
- Headache
- Confusion/delirium
- Impaired consciousness
- Ataxia/gait disorder
- Vision impairment
Three patients were obtunded and one was stuporous. The patients with the highest parasitemia were more likely to be confused.
Severity of Babesia Neurologic Cases
Over half (59.5%) of the patients were admitted to the intensive care unit. Four died.
Ten patients reported transient vision changes. One of these patients was evaluated by an ophthalmologist because she reported seeing colored lights and shapes when she closed her eyes. The ophthalmologist exam was normal.
These findings align with other reports of autonomic and neurologic dysfunction in Babesia patients.
Recovery from Babesia Neurologic Complications
Patients with Babesia have been assumed by some to be asymptomatic after treatment. “Most patients had cleared or improved neurologic symptoms by the time of discharge,” wrote the authors.
“Clinicians working in endemic areas should recognize the range of symptoms associated with babesiosis, including neurologic,” they concluded.
The severity and duration of symptomatic cases of Babesia remains unknown, as Locke points out. “The duration of symptoms after discharge is unknown.”
This uncertainty is consistent with what we see in patients with persistent symptoms after treatment.
Note: The authors did not describe whether other tick-borne co-infections played a role in their patients’ illness. Nor did the authors describe the treatment for their patients.
Frequently Asked Questions
Can Babesia cause neurologic symptoms?
Yes. These complications affected over half of hospitalized patients in this study, including headache, confusion, impaired consciousness, and vision changes.
What are the most common neurologic symptoms?
The most frequent symptoms were headache, confusion/delirium, impaired consciousness, ataxia/gait disorder, and vision impairment.
Who is at higher risk for these complications?
Patients with high parasitemia, renal failure, and diabetes mellitus were more likely to develop neurologic symptoms.
Do neurologic symptoms go away after treatment?
Most patients improved by discharge, but the duration of symptoms after leaving the hospital is unknown.
How serious are babesia neurologic complications?
Very serious. Over 59% of patients in this study were admitted to the ICU, and four patients died.
References
- Locke S, et al. Neurologic Complications of Babesiosis, United States, 2011–2021. Emerging Infectious Diseases. June 2023.
