Lyme Facts
Did you know that Lyme disease is the most common vector-borne
disease in the United States and has reached epidemic proportions??
Basic Lyme Disease Info
Basic
Information about Lyme Disease
Source:
(International Lyme and Associated Diseases Society, Maryland, U.S.)
www.ILADS.org
Updated 4/15/06
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Lyme disease
is transmitted by the bite of a tick, and the disease is
prevalent across the United States and throughout the world.
Ticks know no borders and respect no boundaries. A patient's
county of residence does not accurately reflect his or her Lyme
disease risk because people travel, pets travel, and ticks
travel. This creates a dynamic situation with many opportunities
for exposure to Lyme disease for each individual.
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Lyme disease
is a clinical diagnosis. The disease is caused by a
spiral-shaped bacteria (spirochete) called Borrelia
burgdorferi. The Lyme spirochete can cause infection of
multiple organs and produce a wide range of symptoms. Case
reports in the medical literature document the protean
manifestations of Lyme disease, and familiarity with its varied
presentations is key to recognizing disseminated disease..
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Fewer than 50% of patients with Lyme disease recall a
tick bite. In some studies this number is as low as 15% in
culture-proven infection with the Lyme spirochete.
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Fewer than 50% of patients with Lyme disease recall any
rash. Although the erythema migrans (EM) or “bull’s-eye” rash is
considered classic, it is not the most common dermatologic
manifestation of early-localized Lyme infection. Atypical forms
of this rash are seen far more commonly. It is important to know
that the EM rash is pathognomonic of Lyme disease and requires
no further verification prior to starting an appropriate course
of antibiotic therapy.
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The Centers for Disease Control and Prevention (CDC)
surveillance criteria for Lyme disease were devised to track
a narrow band of cases for epidemiologic purposes. As stated on
the CDC website, the surveillance criteria were never
intended to be used as diagnostic criteria, nor were they meant
to define the entire scope of Lyme disease.
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The ELISA screening test is unreliable. The test
misses 35% of culture proven Lyme disease (only 65%
sensitivity) and is unacceptable as the first step of a two-step
screening protocol. By definition, a screening test should have
at least 95% sensitivity.
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Of patients
with acute culture-proven Lyme disease, 20–30% remain
seronegative on serial Western Blot sampling.
Antibody titers also appear to decline over time; thus while the
Western Blot may remain positive for months, it may not always
be sensitive enough to detect chronic infection with the Lyme
spirochete. For “epidemiological purposes” the CDC eliminated
from the Western Blot analysis the reading of bands 31 and 34.
These bands are so specific to Borrelia burgdorferi that
they were chosen for vaccine development. Since a vaccine for
Lyme disease is currently unavailable, however, a positive 31 or
34 band is highly indicative of Borrelia burgdorferi
exposure. Yet these bands are not reported in commercial Lyme
tests.
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When used as part of a diagnostic evaluation for Lyme disease,
the Western Blot should be performed by a laboratory that
reads and reports all of the bands related to Borrelia
burgdorferi. Laboratories that use FDA approved kits (for
instance, the Mardx Marblot®) are restricted from reporting all
of the bands, as they must abide by the rules of the
manufacturer. These rules are set up in accordance with the CDCs
surveillance criteria and increase the risk of false-negative
results. The commercial kits may be useful for surveillance
purposes, but they offer too little information to be useful in
patient management.
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There are 5 subspecies of Borrelia burgdorferi, over
100 strains in the US, and 300 strains worldwide. This
diversity is thought to contribute to the antigenic variability
of the spirochete and its ability to evade the immune system and
antibiotic therapy, leading to chronic infection.
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Testing for Babesia, Anaplasma, Ehrlichia
and Bartonella (other tick-transmitted organisms) should
be performed. The presence of co-infection with these
organisms points to probable infection with the Lyme spirochete
as well. If these coinfections are left untreated, their
continued presence increases morbidity and prevents
successful treatment of Lyme disease.
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A preponderance of evidence indicates that active ongoing
spirochetal infection with or without other tick-borne
coinfections is the cause of the persistent symptoms in
chronic Lyme disease.
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There has never been a study demonstrating that 30 days of
antibiotic treatment cures chronic Lyme disease. However
there is a plethora of documentation in the US and European
medical literature demonstrating by histology and culture
techniques that short courses of antibiotic treatment fail to
eradicate the Lyme spirochete. Short treatment courses have
resulted in upwards of a 40% relapse rate, especially if
treatment is delayed.
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Most cases of chronic Lyme disease require an extended course of
antibiotic therapy to achieve symptomatic relief. The return of
symptoms and evidence of the continued presence of Borrelia
burgdorferi indicates the need for further treatment. The
very real consequences of untreated chronic persistent Lyme
infection far outweigh the potential consequences of
long-term antibiotic therapy.
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Many patients with chronic Lyme disease require treatment for
1–4 years, or until the patient is symptom-free. Relapses occur
and maintenance antibiotics may be required. There are no tests
currently available to prove that the organism is eradicated or
that the patient with chronic Lyme disease is cured.
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Like syphilis in the 19th century, Lyme disease has been called
the great imitator and should be considered in the
differential diagnosis of rheumatologic and neurologic
conditions, as well as chronic fatigue syndrome, fibromyalgia,
somatization disorder and any difficult-to-diagnose multi-system
illness.
Disclaimer: The foregoing information is for educational
purposes only. It is not intended to replace or supersede
patient care by a healthcare provider. If an individual suspects the
presence of a tick-borne illness, that individual should consult a
healthcare provider who is familiar with the diagnosis and treatment
of tick-borne diseases.
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