What happens to the brain during acute Lyme neuroborreliosis?

A group of researchers from Tulane National Primate Research Center in Louisiana injected live Borrelia spirochete into rhesus monkeys and discovered that inflammation plays a “causal role” in the pathogenesis of acute Lyme neuroborreliosis. Their findings were published recently in The American Journal of Pathology.

Borrelia spirochete are injected into monkeys' brains.

Borrelia spirochete are injected into monkeys’ brains.

Individuals diagnosed with Lyme neuroborreliosis typically suffer from headaches, fatigue, memory loss, learning disabilities, and depression. Clinical findings have included meningitis, cranial neuritis, radiculoneuritis, encephalopathy, encephalitis, encephalomyelitis, radiculitis, radiculoneuritis, mononeuropathies, plexopathies, and demyelinating neuropathies.

Dr. Mario T. Philipp and colleagues at the Tulane National Primate Research Center launched an investigation to examine the role of inflammation on the central nervous system of subjects infected with Borrelia burgdorferi (Bb). Rhesus monkeys were injected with live Bb spirochete. Several monkeys received a potent steroid prior to being injected with the spirochete, while another group was pretreated with a non-steroidal (NSAID) medicine.

The NSAID and control group experienced extensive neurologic damage. The cerebrospinal fluid revealed significantly elevated levels of IL-6, IL-8, chemokine ligand 2, and CXCL13 and pleocytosis in the monkeys, according to a study published in The American Journal of Pathology. Additional pathological changes included:

  1. Leptomeningitis (meningitis)
  2. Vasculitis (inflammation of blood vessels in the brain)
  3. Focal inflammation in the central nervous system
  4. Necrotizing focal myelitis in the cervical spinal cord
  5. Radiculitis (pain that radiates along the nerve due to inflammation on the nerve root at its connection to the spinal column)
  6. Neuritis (inflammation of the nerves)
  7. Demyelination in the spinal roots (erosion of the myelin sheath that normally protects nerve fibers)
  8. Inflammation with neurodegeneration in the dorsal root ganglia (Inflammation and progressive loss of structure or function of neurons in the dorsal root ganglia, or spinal ganglion. The dorsal root ganglion contains the cell bodies of sensory neurons that bring information from the periphery to the spinal cord.)
  9. Neuronal and satellite glial cell apoptosis
  10. Persistent abnormal F-wave chrono dispersions localized to the nerve roots, suggesting damage to axons or demyelination, that were similar to several inflammatory demyelinating peripheral neuropathic disorders, including Guillain-Barré. (Guillain-Barre syndrome is a rare disorder in which your body’s immune system attacks your nerves.)

However, there were no inflammation in the central nervous system of the monkeys that were pretreated with the potent steroid, dexamethasone. 

While the monkey study provides insight into the benefits steroids can play when inflammation is present, it’s also important for clinicians to keep in mind the risks steroids can pose to patients with Lyme disease, as steroids can weaken an already overtaxed immune system.

Clinicians should not prescribe steroids to patients suspected of having Lyme disease, based on this primate study. Unfortunately, pretreatment with the non-steroidal medicine was not effective. Researchers and clinicians must continue to search out ways to control the immune response to Lyme disease without exposing patients to steroids.

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Carolyn Hamilton
Carolyn Hamilton
2 years ago

Dear doctor Cameron, I was bitten by a black legged pacificus ixodes 9 years ago in the San Francisco Bay area when I went camping in the Santa Cruz mountains. After returning home I was sitting in a chair and felt an unusual tingling and then something rolling down my back I looked on the chair and saw a bloody Engorged tick print I went and looked in the mirror And saw A classic big bright red Bullseye rash. I had worked previously as a medical assistant I had seen one patient in the 8 years I worked for a group of 5 internal medicine doctors 1 patient came in and she had classic Bullseye rash on her calf my senior physician diagnosed immediately As a infected tick bite with Lyme Disease. Then prescribed antibiotics for the patient. So, I looked in a mirror and saw a huge bright red classic bullseye rash on my back shoulder blade. I called the primary care provider on my insurance card and explained that I had a bite/rash and wanted to have it looked at in case it was a Lyme infected tick bite. This physician refused to see me. I took myself to a large San Francisco hospital emergency department and the physician confirmed that I had an infected tick bite with Lyme Disease. Said that I needed antibiotics immediately. I was relieved because I remembered how one of my cousins in Utah had an undiagnosed tick bite with Lyme Disease and he had been very ill for 2 years. My Aunt called me and was very upset that my cousin had seen over 20 physicians and no diagnosis. He had suffered for the 2 years then finally diagnosed with positive Lyme Disease and was treated. This was around 1994. He’s fine now. So I knew that the faster I started antibiotics was the best thing to do. However, even though the physician who confirmed that I had Lyme infected bite and needed antibiotics immediately, he refused to prescribe any antibiotics for me. I went 2 years without treatment when I should have been started on antibiotics on day 2 of tick rolling off me. I found Dr. Stricker- ILADS right in San Francisco. He saw me and was upset that no one had treated me. He found two co infections; Rocky Mountain Spotted Fever and Babesia. He started me on variety… Read more »

Carolyn Hamilton
Carolyn Hamilton
2 years ago

Dr. Cameron, no I haven’t seen any other doctors along the way to rule out other illnesses. I’m confused as why you would ask, because I was perfectly healthy when I went camping 9 years ago when a tick attached to my back unknowingly. I didn’t know a thing about Lyme disease with two exceptions; the patient I had seen at work with a classic bullseye rash on her leg, (I never forgot the image of it) – and my cousin who had 2 years of undiagnosed Lyme Disease and his terrible symptoms of pain & extreme fatigue. Those two incidents were back in the late 1990’s. At that time the San Francisco Bay area had a lot of what they called “The Yuppie Syndrome” and “Chronic Fatigue” My guess is that people were infected with Borellia and didn’t know it. Physicians only recognized Lyme Disease if they saw bright red circles expanding outwards – as the CDC ruled the only way to diagnose Lyme Disease. Physicians didn’t know how to treat, test or diagnose unless they saw a Classic bullseye rash – my Bullseye lasted for exactly 10 days. So it was a confusing time, especially if a person couldn’t see a bullseye rash before it faded away or if they never had a rash to begin with, as you well know. So nine years ago I went camping for a short weekend then came home to San Francisco when the tick detached from my back shoulder blade and rolled down my back. I looked & saw an engorged bloody tick on my chair and because of the two earlier lessons I learned about “very basic” Lyme Disease I was able to put it together, although as you said; It WAS extremely unfortunate that the physician who was kind and knowledgeable ~ he knew that the Classic Bullseye Rash that he was looking at on my back was definitely an infected tick bite with Lyme Disease. He confirmed it in the hospital records and the CMA & CDC. I asked him multiple times why I wasn’t given the antibiotics that he himself said I needed immediately. His only answer was that he “wasn’t allowed to treat patients because he was only a n emergency department physician”. No, it makes no sense, he wouldn’t prescribe abx for Strept throat? Ear infections? I was so convinced from working in the San… Read more »

1 year ago

Have you ever read the following book from Stephen Bruhner(?): “Healing Lyme: Natural Healing of Lyme Borreliosis and the Coinfections Chlamydia and Spotted Fever Rickettsiosis, 2nd Edition”. The writer goes into really interesting and potent therapies for lyme, and the comment reviews on Amazon report very positive effects and full-on remissions from lyme through the therapies suggested in the book.

Fair warning, the book is a thick read, so you might need someone to go through the information for you and help you to digest it, what with your brain fog being still present. That said, many of the folks said that they could recuperate so much in one month on the protocol that they could study the book themselves(despite having heavy brain fog earlier) and do their own homework. Please check out the book, perhaps it might help you.


2 years ago


I am 44 years old, and had emergency neurosurgery in 2011 for hydrocephalus caused by aqueduct stenosis. I had been experiencing gradually worsening neurological symptoms for years, including severe headaches, visual disturbance and depression. I began experiencing the severe headaches in the years after I recall being bitten as an 11 year old child by a black legged tick in Spain. I developed the bulls eye reaction and high fever. I don’t recall being given more than a couple of days’ medication, presumably an antibiotic. My neurosurgeon explained that my aqueducts had ‘silted’ with scar tissue over many years, causing the hydrocephalus. Could my brain damage have been caused by untreated lymes?

Ellen Chiapperini
Ellen Chiapperini
2 years ago

Dr. Cameron:
I started January 1,2020 with severe chronic headaches on back, left side of head. After several tests and successful left carotid artery surgery for blockage in March, I began having neurological symptoms: mouth drooping to the right, weak muscle control of tongue, tongue going to left when I was asked to stick it out by neurologist, trouble chewing, and trouble concentrating. Those symptoms began about 10 days after carotid surgery. I have added symptoms in the last 4-6 weeks, of some difficulty swallowing, hoarseness in voice, and increased brain fog and forgetfulness. After a huge battery of tests the only thing positive was Lyme disease which was treated with 3 weeks of doxycycline, but I felt no differently. The neurologist still is trying to find the cause of ongoing symptoms.
Do you have any insight about Lyme and what is going on with me?

ilana drucker
ilana drucker
2 years ago

To what extent is disassociation due to chronic Lyme and/or Bartonella? I have an MRI showing non-specific white matters, a high result for basic myelin protein, postive Bart test, 2 + Lyme bands (39 and 41), and nearly 4 years of mostly psych symptoms, especially disassociation, depression, and panic. I’m receiving SOT treatment next week.