What is Lyme Disease?
Lyme disease (LD) is a multi-system bacterial infection caused by a the spirochete Borrelia burgdorferi (Bb). The pathogen was named in honor of the discoverer and a founding board member of the Lyme Disease Foundation, Willy Burgdorfer, PhD, MD (hon).
Research has proven that the bacterium that causes Lyme disease has been in the U.S. for over 100 years.
These spirochetes are maintained in nature in the bodies of wild animals and is transmitted from one animal to another through the bite of an infective tick. Humans and pets are incidental hosts to ticks.
The body does not maintain a natural immunity to the disease. Thus, a person can be reinfected with the disease on subsequent tick bites.
The causative agent, Borrelia burgdorferi, is a type of spirochete. Spirochetes are long, thin, spiral-shaped bacteria. Other spirochetes include the causative agents of syphilis, relapsing fever, and gum disease.
The bacterium is thousands of times larger than a virus. However, it still requires a powerful microscope to see one. Roughly 1,500 Bb must be laid end to end to equal one inch. About 100,000 of Bb laid side to side would equal one inch.
When Bb was first discovered in 1982 it was thought that there was just one strain. Since then, about 100 U.S. and 300 worldwide strains of the bacterium have been discovered.
In the mid-1990's genospecies were formed to group the many variations into subcategories.
" Borrelia burgdorferi sensu lato" is name given to the overall category. In North America there is just one genospecies variant - Bb sensu stricto. In Europe there are three categories Bb sensu stricto, B. garinii, and B. afzelii. Asia has B. garinii and B. afzelii. Japan has B. japonica and B. miyamoto. These groups are evolving as new research discoveries occur.
A new pathogen causing Lyme or "Lyme-like" disease has been reported. While not culturable, it has been named B. lonestari sp.
The bacterium is able to move around the body through the bloodstream and between tissue. It can also invade tissue, replicate, and leave the cell - destroying the cell as it emerges. Sometimes, as the bacterium emerges, the cell wall collapses around the bacterium, forming a "cloaking device". This action may aid the bacteria's ability to hide from the immune system response.
are the Symptoms of Lyme Disease?
LD symptoms can imitate other diseases and can be misdiagnosed.
EARLY LOCALIZED DISEASE
Signs and symptoms of Early Local Lyme Disease often starts with flu-like feelings of headache, stiff neck, fever, muscle aches, and fatigue. About 60% of light-skinned patients notice a unique enlarging rash, referred to as erythema migrans (EM), days to weeks after the bite. On dark-skinned people, this rash resembles a bruise.
The rash may appear within a day of the bite or as late as a month later. This rash may start as a small, reddish bump about one-half inch in diameter. It may be slightly raised or flat. It soon expands outward, often leaving a clearing (normal flesh color) in the center. It can enlarge to the size of a thumb-print or cover a persons back.
To be considered local disease the rash must be at the tick bite site with no other major organ system involvement. A rash occurring at other than the bite site in an indication of Disseminated Lyme Disease.
Don't confuse a local reaction to a tick bite, with signs of infection. A small inflamed skin bump or discoloration that develops within hours of a bite and over the next day or two is not likely to be due to infection - but rather a local reaction to the disruption of the skin.
DISSEMINATED LYME DISEASE
Some people do not notice these early indicators of infection. Early manifestations usually disappear, and disseminated (other organ system involvement) infection may occur. General symptoms alone do not indicate Lyme disease.
Profound fatigue, severe headache, fever(s), severe muscle aches/pain.
Nerve conduction defects (weakness/paralysis of limbs, loss of reflexes, tingling sensations of the extremities - peripheral neuropathy), severe headaches, stiff neck, meningitis, cranial nerve involvement (e.g. change in smell/taste; difficulty chewing, swallowing, or speaking; hoarseness or vocal cord problems; facial paralysis - Bell's palsy; dizziness/fainting; drooping shoulders; inability to turn head; light or sound sensitivity; change in hearing; deviation of eyeball [wandering or lazy eye], drooping eyelid), stroke, abnormal brain waves or seizures, sleep disorders, cognitive changes (memory problems, difficulty in word finding, confusion, decreased concentration, problems with numbers) and, behavioral changes (depression, personality changes).
Other psychiatric manifestations that have been reported in the scientific literature include: panic attacks; disorientation; hallucinations; extreme agitation; impulsive violence, manic, or obsessive behavior; paranoia; schiziphrenic-like states, dementia, and eating disorders. Several patients have committed suicide.
Vision changes, including blindness, retinal damage, optic atrophy, red eye, conjunctivitis, "spots" before eyes, inflammation of various parts of the eye, pain, double vision.
Rash not at the bite site (EM) - This skin discoloration varies in size and shape; usually has rings of varying shades, but can be uniformly discolored; may be hot to the touch or itch; ranges in color from reddish to purple to bruised-looking; and can be necrotic (crusty/oozy). The rash may develop a bull's-eye rash or target look. The shape my be circular, oval, triangular, or a long-thin ragged line.
Other disseminated skin problems include:
which is a benign nodule or tumor, and
acrodermatitis chronica atrophicans (ACA) which is discoloration/degeneration usually of the hands or feet.
HEART and BLOOD VESSELS
Irregular beats, heart block, myocarditis, chest pain, vasculitis.
Pain - intermittent or chronic, usually not symmetrical; sometimes swelling; TMJ-like pain in jaw.
Mild liver function abnormalities.
Difficulty breathing, pneumonia.
Pain, inflammation, cramps, loss of tone.
Nausea, vomiting, diarrhea, loss of appetite, anorexia.
Miscarriage, premature birth, stillbirth, and neonatal deaths (rare). Congenital LD has been described in medical literature.
It is possible for the bacterium to pass from mother to fetus across the placenta, resulting in congenitally acquired LD. A link between LD and adverse outcomes in pregnancy is under investigation. However, most studies show that mothers who are promptly diagnosed and treated appear to have perfectly normal babies.
Nursing women with LD often call to ask us whether they should continue nursing. There has been no proved cases of transmission through human milk. There is research that demonstrates that Bb can be found in the colostrum of infected cows and mice. Animals studies have demonstrated that ingestion of Bb can result in infection. Some physicians recommend nursing mothers discard breast milk during active infection. Breast feeding can resume after treatment is completed and the woman becomes symptom-free. The decision to do so should be discussed with your physician.
is Lyme Disease Diagnosed?
There is no test that can determine if a patient is infected with the LD bacterium and then demonstrate that the patient has become bacterium-free. Therefore, LD is clinical diagnosis, based on signs and symptoms, with the patients travel history to endemic areas and test results being additional pieces of information in the complete picture. No test can "rule-out" Lyme disease.
INDIRECT TESTS (Antibody Tests)
Antibodies are the immune system's response to "fight off" infection. Tests strive to be both sensitive (detecting any LD antibodies) and specific (detecting just LD antibodies).
tests occur due to defects in test sensitivity; too low an antibody level
to detect (e.g. they are bound to the bacteria, with too few free-floating;
the patient taking antibiotics or other drugs; naturally low antibody
production); the bacterium has changed, limiting recognition by the immune
system; or bacterial strain variations.
False positive tests occur due to test failure or cross-reacting antibodies (e.g. syphilis, periodontal disease, ANA or RF).
Types of Tests
EIA, IFA) - These tests measure the level of Bb antibodies in fluid. Laboratories
use different detection criteria, cut-off points, types of measurements,
Western blot - This test produces bands indicating the immune system's reactivity to Bb. Laboratories differ in their interpretation and reporting of these bands.
C6 Lyme Peptide ELISA - identifies antibodies to a consistent surface protein that is present on every known strain of the Lyme disease bacteria, Borrelia burgdorferi (Bb). The C6LPE is more sensitive for diagnosing all stages of Lyme disease, including those patients with late stage Lyme disease.
DIRECT DETECTION TESTS
- These tests detect a unique Bb protein in fluid (e.g. urine) of patients.
This may be useful for detecting LD in patients taking antibiotics or
during symptom flare-up.
Polymerase chain reaction (PCR) - This test multiplies the number of Bb DNA to a detectable measurable level.
Culturing - Growing the bacterium in culture is difficult and can take months.
Staining - Staining of tissue is time consuming and has low yield. The problem is that in Lyme disease there are too few of the Lyme spirochete in the body, and could result in the biopsy having no bacteria.
is Lyme Disease Treated?
Treatment varies and depends on how early a diagnosis is made and the organ system(s) involved. No definitive treatment regimens have been determined, and failures occur with all protocols.
Oral antibiotics may be sufficient for early stages of non-disseminated infection.
Long-standing or Disseminated Lyme Disease responds best to one or several courses of either oral or intravenous antibiotics.
Physicians and researchers agree that it is unethical not to treat people with demonstrated, persisting infection. Therefore, some people receive retreatment or longer treatment.
(Reprinted with the permission of the Lyme Disease Foundation)