Can Anaplasmosis Affect the Brain? Neurologic Symptoms and Recovery
Anaplasmosis can rarely affect the brain
Confusion, memory loss, and other neurologic symptoms may occur
Most patients improve with prompt doxycycline treatment
Anaplasmosis can rarely affect the brain, causing confusion, aphasia, memory loss, and, in exceptional cases, bleeding around the brain. Although most people with anaplasmosis develop fever, chills, headache, and muscle aches, central nervous system involvement has been reported. This case illustrates how neurologic anaplasmosis can present and what recovery may look like.
In this episode of the Inside Lyme Podcast, I discuss the case of a 64-year-old woman who developed central nervous system involvement from anaplasmosis, highlighting the importance of early recognition and prompt treatment.
The case was first described by Mullholand and colleagues in the British Medical Journal in a paper entitled “Central nervous system involvement of anaplasmosis.”1
Can anaplasmosis affect the brain?
A 64-year-old woman was hospitalized with a 24-hour history of confusion and lethargy. The following morning, her lethargy had worsened, and she developed subjective fever, mild headache, nausea, vomiting, and increasing confusion, according to the authors.
Her physical examination revealed aphasia, memory loss involving the previous 24 hours, and an engorged tick behind her knee.
Brain imaging demonstrated leptomeningeal enhancement and bilateral frontal lobe subarachnoid hemorrhage (SAH), indicating rare central nervous system involvement.
What is leptomeningeal enhancement?
The leptomeninges are the two innermost membranes that surround the brain and spinal cord. Leptomeningeal enhancement on MRI indicates inflammation or irritation of these tissues and may occur with infectious meningitis, viral or bacterial infections, autoimmune disorders, vasculitis, sarcoidosis, trauma, or metastatic cancer.1
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Diagnosing neurologic anaplasmosis
The patient’s serum PCR test for Anaplasma phagocytophilum was positive, confirming the diagnosis. A spinal tap was not performed. PCR testing is generally most useful during the early stages of illness before antibiotic treatment is started.
The authors noted that symptoms of anaplasmosis may develop as early as 24 hours after transmission, although the incubation period is typically longer in most patients. Neurologic involvement is uncommon and is reported more frequently in Lyme disease and ehrlichiosis than in anaplasmosis.
Testing for Lyme disease and other tick-borne co-infections was negative. However, the authors acknowledged that these tests may be negative early in the course of illness before an antibody response has developed.
Clinical perspective: In my practice, patients with suspected tick-borne illness often have Lyme disease or another tick-borne co-infection. Because ticks can transmit more than one pathogen during a single bite, it is important to consider the possibility of co-infections when patients present with compatible symptoms. Early testing may be negative, so clinical judgment remains important.
Treatment for anaplasmosis
The woman was treated with doxycycline and discharged home.
However, she was hospitalized again six weeks later because of persistent headache, word-finding difficulty, memory loss, and generalized fatigue.
Repeat MRI and MRA demonstrated increased FLAIR hyperintensity and hypointensity involving the bilateral frontal, parietal, and occipital lobes, findings consistent with subarachnoid hemorrhage and persistent left middle cerebral artery anterior division vasospasm.
She was discharged without additional antibiotic treatment, and speech therapy was arranged.
Three months later, the patient had experienced marked improvement and returned to her cognitive baseline.
Long-term effects and recovery from anaplasmosis
Most patients with anaplasmosis improve with appropriate doxycycline treatment. However, recovery may not always be immediate, particularly when the illness is severe or neurologic complications are present.
In this unusual case, the patient experienced persistent headache, word-finding difficulty, memory loss, and generalized fatigue for several weeks after her initial hospitalization. Despite subarachnoid hemorrhage and cerebral vasospasm, she gradually improved and returned to her cognitive baseline approximately three months later.
Persistent fatigue, headache, brain fog, cognitive slowing, and word-finding difficulty may be reported during recovery. These symptoms do not necessarily indicate that the infection remains active, but they warrant continued clinical evaluation, particularly when symptoms are severe, progressive, or accompanied by new neurologic findings.
Frequently Asked Questions
Can anaplasmosis affect the brain?
Yes. Neurologic involvement is uncommon, but anaplasmosis has been associated with confusion, altered mental status, aphasia, memory loss, meningitis-like findings, and other central nervous system complications.
Can anaplasmosis cause neurological symptoms?
Yes. Reported neurological symptoms include confusion, lethargy, aphasia, memory loss, headache, word-finding difficulty, brain fog, and cognitive slowing. Severe complications are rare but may include meningeal inflammation, cerebral vasospasm, or bleeding around the brain.
What are the long-term effects of anaplasmosis in humans?
Most patients recover with treatment, but fatigue, headache, weakness, brain fog, word-finding difficulty, and other cognitive symptoms may continue for weeks or months in some individuals. Persistent or worsening symptoms should be evaluated for complications, co-infections, or another diagnosis.
How long does recovery from anaplasmosis take?
Recovery time varies depending on the severity of the illness, how quickly treatment begins, and whether complications develop. Some patients improve rapidly with doxycycline, while others may experience lingering fatigue or cognitive symptoms for several weeks or months.
Can Lyme disease or another tick-borne infection occur with anaplasmosis?
Yes. The same ticks that transmit anaplasmosis may also transmit Lyme disease, babesiosis, or other tick-borne infections. Early laboratory testing may be negative, so clinicians should consider co-infections when symptoms, exposure history, or the clinical course suggest another tick-borne illness.
How is neurologic anaplasmosis treated?
Doxycycline is the standard treatment for anaplasmosis and should generally be started promptly when the infection is strongly suspected. Patients with severe neurologic symptoms may require hospitalization, brain imaging, and additional supportive care.
Clinical Takeaway
Although neurologic complications of anaplasmosis are uncommon, the infection should be considered in patients who develop acute confusion, memory loss, aphasia, severe headache, or other neurologic symptoms following possible tick exposure.
Lyme disease and other tick-borne co-infections may also need to be considered, particularly when symptoms overlap or testing is performed early in the illness.
Although neurologic anaplasmosis is rare, prompt recognition, consideration of co-infections, and early doxycycline treatment offer the best chance for full neurologic recovery.
Related Articles
Other tick-borne infections can also produce neurologic or systemic symptoms. Learn more:
Lyme disease co-infections
Neurological Lyme disease symptoms
Babesia symptoms and treatment
Ehrlichiosis symptoms and treatment
This case is also discussed in an episode of the Inside Lyme Podcast, where I review the clinical presentation, diagnosis, treatment, and recovery.
References:
- Mullholand JB, Tolman N, De Obaldia A, et al. Central nervous system involvement of anaplasmosis. BMJ Case Reports CP. 2021;14:e243665.
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
Is there any indication of how long the woman had been on doxy?
The authors did not indicate how long she was treated. They did state that Anaplasmosis is typically treated for 10 days.
Hi Dr Cameron,how do you treat anaplasmosis,and other lyme infections,im in the UK, they are in complete denial of lyme over here.Do you use anti biotics only or a combination of things.thanks
I typically use oral doxycycline. I use Rifampin as a backup. I use other treatments if I suspect other tick borne infections. I have needed to use IV antibiotics on some occasions for tick borne illnesses.
My mother showed signs of rapid deterioration (confusion, disorientation) after she notice a tick attachment on the back of her neck 4 years ago. I got no help locally so I took her to a larger hospital and in the testing an abnormal result in spinal fluid and one Dr. had a suspicion that Lyme disease was the culprit. She was treated with Rocephin For 60 days. She responded immediately to the antibiotics and in 60 days was nearly back to normal. Now, years later I am seeing some confusion and dizziness set in. How can I find out if this is a Lyme relapse or true dementia starting?
I advise my patients to work with a neurologist and a doctor experienced in treating Lyme disease. Keep fighting for your mother.