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Lyme Disease


The first symptom of Lyme Disease is a skin lesion. Known
as erythema chronicum migrans, or ECM, this usually begins
as a red discoloration (macule) or as an elevated round
spot (papule). The skin lesion usually appears on an
extremity or on the trunk, especially the thigh, buttock or
the under arm. This spot expands, often with central
clearing, to a diameter as large as 50 cm (c. 12 in.).
Approximately 25% of patients with Lyme Disease report
having been bitten at that site by a tiny tick 3 to 32 days
before onset of ECM. The lesion may be warm to touch. Soon
after onset nearly half the patients develop multiple
smaller lesions without hardened centers. ECM generally
lasts for a few weeks. Other types of lesions may
subsequently appear during resolution. Former skin lesions
may reappear faintly, sometimes before recurrent attacks of
arthritis. Lesions of the mucous membranes do not occur in
Lyme Disease.
The most common symptoms accompanying ECM, or preceding it
by a few days, may include malaise, fatigue, chills, fever,
headache and stiff neck. Less commonly, backache, muscle
aches (myalgias), nausea, vomiting, sore throat, swollen
lymph glands, and an enlarged spleen may also be present.
Most symptoms are characteristically intermittent and
changing, but malaise and fatigue may linger for weeks.
Arthritis is present in about half of the patients with
ECM, occurring within weeks to months following onset and
lasting as long as 2 years. Early in the illness, migratory
inflammation of many joints (polyarthritis) without joint
swelling may occur. Later, longer attacks of swelling and
pain in several large joints, especially the knees,
typically recur for several years. The knees commonly are
much more swollen than painful; they are often hot, but
rarely red. Baker's cysts (a cyst in the knee) may form and
Those symptoms accompanying ECM, especially malaise,
fatigue and low- grade fever, may also precede or accompany
recurrent attacks of arthritis. About 10% of patients
develop chronic knee involvement (i.e. unremittent for 6
months or longer).
Neurological abnormalities may develop in about 15% of
patients with Lyme Disease within weeks to months following
onset of ECM, often before arthritis occurs. These
abnormalities commonly last for months, and usually resolve
completely. They include: 

1. lymphocytic meningitis or meningoencephalitis 
2. jerky involuntary movements (chorea) 
3. failure of muscle coordination due to dysfunction of the
cerebellum (cerebellar ataxia) 
4. cranial neuritis including Bell's palsy (a form of
facial paralysis) 
5. motor and sensory radiculo-neuritis (symmetric weakness,
pain,strange sensations in the extremities, usually
occurring first inthe legs) 
6. injury to single nerves causing diminished nerve
response(mononeuritis multiplex) 
7. inflammation of the spinal cord (myelitis).
Abnormalities in the heart muscle (myocardium) occur in
approximately 8% of patients with Lyme Disease within weeks
of ECM. They may include fluctuating degrees of
atrioventricular block and, less commonly, inflammation of
the heart sack and heart muscle (myopericarditis) with
reduced blood volume ejected from the left ventricle and an
enlarged heart (cardiomegaly).
When Lyme Disease is contracted during pregnancy, the fetus
may or may not be adversely affected, or may contract
congenital Lyme Disease. In a study of nineteen pregnant
women with Lyme Disease, fourteen had normal pregnancies
and normal babies.
If Lyme Disease is contracted during pregnancy, possible
fetal abnormalities and premature birth can occur.
Etiology --------------------------------
Lyme Disease is caused by a spirochete bacterium (Borrelia
Burgdorferi) transmitted by a small tick called Ixodes
dammini. The spirochete is probably injected into the
victim's skin or bloodstream at the time of the insect
bite. After an incubation period of 3 to 32 days, the
organism migrates outward in the skin, is spread through
the lymphatic system or is disseminated by the blood to
different body organs or other skin sites.
Lyme Disease was first described in 1909 in European
medical journals. The first outbreak in the United States
occurred in the early 1970's in Old lyme, Connecticut. An
unusually high incidence of juvenile arthritis in the area
led scientists to investigate and identify the disorder. In
1981, Dr. Willy Burgdorfer identified the bacterial
spirochete organism (Borrelia Burgdorferi) which causes
this disorder.
Affected Population --------------------------------
Lyme Disease occurs in wooded areas with populations of
mice and deer which carry ticks, and can be contracted
during any season of the year.
Related Disorders --------------------------------
Rheumatoid Arthritis is a disorder similar in appearance to
Lyme Disease. However, the pain in rheumatoid arthritis is
usually more pronounced. Morning stiffness and symmetric
joint swelling more commonly occur in rheumatoid arthritis,
and knotty lumps under the skin may be present over bony
prominences. Bony decalcification which can be prominent in
Rheumatoid Arthritis is detected on X-rays.
Brachial Neuritis, also known as Parsonnage-Turner
Syndrome, is a common inflammation of a group of nerves
that supply the arm, forearm, and hand (brachial plexus).
It is characterized by severe neck pain in the area above
the collarbone (supraclavicular) that may radiate down the
arm and into the hand. There also may be weakness and
numbness (hyperesthesia) of the fingers and hands. Although
many cases have no apparent cause, this syndrome may occur
following an immunization (tetanus or diptheria), surgery,
or infection with Lyme Disease. 

Therapies: Standard --------------------------------
For adults with Lyme Disease the antibiotic tetracycline is
the drug of choice. Penicillin V and erythromycin have also
been used. In children penicillin V is recommended rather
than tetracycline. Penicillin V is now recommended for
neurological abnormalities. It is not yet clear whether
antibiotic treatment is helpful later in the illness when
arthritis is the most predominant symptom. Treatment should
be started as soon as the rash appears, even before the
Enzyme Linked Immunoabsorbent Assay (ELISA) test is
completed. Results of this test may be inaccurate if
patients have had antibiotics soon after contracting Lyme
Disease, or in those who have weakened immune systems.
If Lyme Disease is contracted during pregnancy, careful
monitoring by physicians is highly recommended to avoid
possible fetal abnormalities and/or complications.
For tense knee joints due to increased fluid flowing in the
joint spaces (effusions), the use of crutches is often
helpful. Aspiration of fluid and injection of a
corticosteroid may be beneficial. If the patient with Lyme
disease has marked functional limitation, excision of the
membrane lining the joint (synovectomy) may be performed
for chronic (6 months or more despite therapy) knee
effusions, but spontaneous remission can occur after more
than a year of continuous knee involvement.
When Lyme Disease is contracted during pregnancy, treatment
with penicillin should begin immediately to avoid the
possibility of fetal abnormalities.
In 1989 a new Lyme Disease antibody test, manufactured by
Cambridge Biosciences Corp., was approved by the FDA. This
test is being used by local laboratories throughout the
nation, making tests more available to the general
population. However, it is 97% specific for antibodies to
Lyme disease when compared to Western blot tests, but it
cannot identify the live bacteria in patients who have not
yet developed the antibodies.
Therapies: Investigational --------------------------------
Researchers are trying to develop a test that will identify
the Lyme Disease bacteria in patients who have not yet
developed the antibodies. This would enable doctors to
diagnose Lyme Disease very early in the course of the



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