Brain fog and memory loss: Not Lyme

Let me say at the outset: this entry is primarily defensive. But I also think it is necessary that my readers understand that I not just a "Lyme MD." Unlike a specialist,(Lyme medicine is not a speciality) I was trained as a generalist. For me that has meant that I have the ability to look at the whole person: all the various systems in the body and their inter-relations. I recently spoke with an opthomologist who jokingly said: "I only specialize on cataract surgery of the left eye." As a generalists, I view my patients through a broader, more integrative model. I think this also creates an open mind set, more adaptive to paradigm changes such as those created with new ways of thinking about Lyme disease. It is interesting to note that LLMDs from the most part come from primary care disciplines, family medicine and internal medicine. Physicians who have specialized, infectious disease and rheumatology are much less open minded. I suspect it is their DNA- so to speak.


Every symptom seen in chronic Lyme patients can also be seen in a wide array of other medical syndromes. It is when multi-system symptoms converge in a single individual that Lyme becomes the primary suspect. Brain fog and memory loss are perhaps one of the most common symptoms seen in chronic Lyme patients. One should always consider that it is not always the case that Lyme is the imitator; sometimes the table is turned- it is another illness which is masquerading as Lyme.

In what follows, I will provide a brief over view of some of the causes of brain fog and cognitve changes in patients which are not due to Lyme disease.

Cognitive deficits are frequently seen with alcohol and substance abuse. A chronic, late stage alcoholic may have a dementia called Korsakofs syndrome, associated with "confabulation." Psychiatric disorders including: depression, anxiety, bipolar disorder and attention deficit disorder may cause the same symptoms. These symptoms can be caused by sleep apnea- which is extremely common- both central and obstructive. Other sleep disorders may include restless leg syndrome and narcolepsy. Non-Lyme autoimmune causes may include: gluten sensitivity, lupus(cerebritis),vasculiltis, MS and others.

Non-Lyme neurodegenerative causes may include: early onset Alzheimer's disease, Parkinson's disease with Lewy body dementia, fronto-temporal dementia and others. Prions, mutated proteins may cause severe cognitive problems, the best known example is mad cow disease(BSE). Brain tumors- either primary or metastatic need to be considered. Neurological disease can also be the result of "paraneoplastic" syndromes. For example, a patient might have lung cancer and the cancer might provoke the development of peculiar auto-antibodies such as anti-Hu or anti-Ro, which cause inflammation of brain tissue. Other infections need to be considered. These include: syphilis, chronic fungal meningitis, viral encephalitis such as Herpes and many others, brain abscess with a variety of microbes including parasites.

Injury needs to be considered. Patients may have a slow bleed around the brain- a subdural hematoma. Patients may have a post-concussion syndrome. The injury may be psycho-physiologic as in PTSD. Low grade atypical seizures can cause these symptoms and need to be considered. Metabolic causes of change in mental status are always a concern. Patients can have fluctuations in blood sugar. My first medicine patient when I was a 3rd year medical student had an insulinoma, an unusual tumor of the pancreas which would secrete insulin at unexpected times. The low blood sugars would have significant brain/cognitive effects. This syndrome(hypoglycemia) is more likely in diabetics, especially those on insulin and certain oral medicines. Vitamin B12 deficiency is a notorious cause of mental status changes as is hypothyroidism.
Systemic infections, especially in the elderly, like pneumonia or a urinary tract infection can cause significant changes in mentation. Low oxygen levels seen in patients with chronic lung disease, congestive heart failure, blood clots to the lungs and others disorders can cause dramatic mental status change. Toxic exposure to a wide range of brain toxins can precipitate cognitive changes. Belladonna like drugs- anti-cholinergics, are a good example. Heavy metals like lead and mercury are very toxic to the central nervous system. Multiple medications from a wide range of classes as well as toxic drug interactions can cause these problems.

Many patients with changes in mental status suffer with the most common disease in America, atherosclerosis. Both clogged arteries and high blood pressure can cause tiny strokes in multiple regions of the brain ultimately leading to memory changes.
This syndrome is much more common in diabetics.

Genetic factors have been identified which are associated with various forms of dementia and neurodegenerative disorders. This of course includes Alheimer's disease.

Perhaps there is a phenomenon of mild forgetfulness associated with aging. I was taught this in medical training. Perhaps it is because I am of that certain age that I am dubious of this explanation unless all other causes have been ruled out.

There is evidence that persons with active minds, those who are engaged in work, problem solving or do puzzles, may preserve cognitive abilities.

This list is not meant to be exhaustive but illustrative. Lyme docs have been criticized as being hammers who see everything as nails-(Lyme).
Those of us who treat Lyme spent many years learning general medicine before we ever became involved in Lyme diagnosis and treatment. We have not abandoned that foundation of knowledge.

I have written this piece, like most of my others, off the top of my head, so please excuse any spelling errors.

A similar list could be constructed for every other symptoms commonly seen in Lyme patients,including: fatigue, muscle pain, joint pain, numbness and tingling, sweats- fevers and chills, headache, dizziness and many more. I would be happy to do this if there is an interest.

I am a family doctor. I see a wide range of patients in my office everyday with a multitude of medical diagnoses. I do not diagnose everyone with Lyme disease as some have suggested. However, I do believe that the Lyme pandemic/epidemic is real. I do find many patients with symptoms, signs and ancillary diagnostic tests which point in that direction.

When I was a medical intern, almost 30 years ago, at DC General Hospital, I remember something a very bright senior medical resident once said. "Every time I get an interesting, exciting case- it always turns out to be tainted by alcoholism."
I will admit, to some extent, that statement reflects my current view of Lyme disease. Nonetheless, my first priority is to practice solid, standard medicine and then put the pieces of the puzzle together to the best of my abilities.