WHAT
IS LYME DISEASE?
Lyme disease is a
world-wide infectious disease caused by microscopic bacteria carried by
tiny ticks.
 |
B.
burgdorferi, a spiral bacteria that
causes Lyme Disease, seen through a microscope. |
HOW
IS LYME TRANSMITTED?
There are several
species of deer ticks across the US that become infected with the spiral
bacterium Borrelia burgdorferi. Unsuspecting humans and animals
walking through woodlands and brushy areas may be bitten by a tick and
never know it. The tiny ticks, some the size of poppy seeds, may stay
on your body for hours to days. The tick engorges itself with blood. If
infected, the spirochete is transmitted to the bloodstream of the person
or animal during the bite.
WHAT
IF I SUSPECT EXPOSURE?
Early recognition
is important. If you find a tiny tick attached to your skin, if you were
in a known tick-infested area, or if you have symptoms described herein,
see your physician.
WHAT
ARE THE SYMPTOMS?
A characteristic
red bulls-eye rash (EM) at the site of the bite is present in less than
40% of patients. The rash may appear within days to weeks after the bite,
but could be hidden in hairline or underarms.
 |
EM
RASH — Rashes from other bacteria in the tick may show up immediately.
Typically the rash from Lyme bacteria appears days or weeks after
the bite. |
Some patients report
flu-like symptoms, fever, aches, fatigue, neck stiffness, jaw discomfort,
muscle pain and stiffness, swollen glands, and red eyes. Symptoms may
appear, disappear and reappear at various times.
Nervous system abnormalities
include memory loss and partial facial paralysis (Bell's palsy). Migratory
joint pains, and pains in the tendons, muscles and bones may occur later
in the disease. Arthritic symptoms, if present, usually affect the large
joints like the knees.
HOW
IS LYME DISEASE DIAGN0SED?
Lyme disease is a
clinical diagnosis, This means that the physician makes the diagnosis
using your clinical history and symptoms. If a physician observes an EM
rash, a diagnosis of Lyme disease will be made. If a rash is not seen
by a physician, laboratory tests are often needed to help with the diagnosis.
CAN
TICKS BE TESTED?
Not all ticks are
infected with the spiral bacterium B. burgdorferi. If the tick
was saved, it can be identified and tested. Our laboratory tests ticks
for the presence of the Lyme bacteria using a test called PCR. We can
also test ticks for Babesia microti and Babesia WA-1, Ehrlichia,
and Bartonella henselae. These diseases are also carried by ticks.
 |
From
left to right: Larvae, Nymph, Female, Male Tick
Tick in Nymph stage is the size of a poppy seed. |
ARE
THERE OTHER TICK-BORNE DISEASES?
The same tick that
carries the bacteria that causes Lyme Disease, can also transmit other
illnesses. The most common are Babesiosis, Ehrlichiosis, and Bartonella
henselae. It is estimated that up to 20% of the ticks with Lyme disease
may have one of these other diseases. Babesiosis is like malaria, with
the symptoms of acute disease being fever, chills, vomiting and fatigue.
It is usually self-limiting, except in patients who have undergone splenectomy.
There are two forms of Ehrlichiosis: HGE (Human Granulocytic Ehrlichiosis)
and HME (Human Monocytic Ehrlichiosis). HGE is primarily on the East coast,
upper Midwest and California. HME is primarily in the Southeast, lower
Midwest and Southwest. These acute diseases may have symptoms of fever,
chills, vomiting and fatigue and require prompt antibiotics. Subclinical
forms of these diseases may be present in patients with Lyme disease.
WHAT
TESTS ARE AVAILABLE?
A variety of tests
is available. Many doctors who are unfamiliar with Lyme disease may just
use the Lyme test available in their local laboratory. In many cases this
is the Lyme ELISA or IFA, often called "Titer Test.”
These tests measure a patient's antibody, IgM and/or IgG, in response
to exposure to the Lyme bacteria. By today's standards, these tests are
not very sensitive. IGeneX, Inc. will only perform the ELISA test when
Western Blots are ordered in conjunction.
The Western Blot
tests (IgG and/or IgM) are much more sensitive and specific than the above
ELISA tests. With the Western blot, the laboratory can visualize the exact
antibodies you are making to the Lyme bacteria. In some cases the laboratory
may be able to say that your “picture of Lyme antibodies” is
consistent with early disease or with persistent/ recurrent disease. Not
all patients have antibodies at all times when tested. Antibodies are
more commonly detected within the first year after infection, although
re-infection may cause a significant rebirth of antibodies. At most, only
70% of patients have antibodies early, and the presence of antibodies
alone does not make a disease diagnosis.
The Lyme Dot
Blot Assay (LDA) looks for the presence of pieces of the Lyme bacteria
in urine. The LDA has been useful in some patients with clinical symptoms
and clinical history consistent with Lyme disease, who consistently test
negative with antibody tests for Lyme disease.
The PCR (Polymerase
Chain Reaction) test detects the presence of the DNA of
the Lyme bacteria. PCR tests have more sensitivity early in the disease
before patients have received antibiotics. The best specimen to test has
not been defined. The test is usually performed on whole blood, serum,
urine, CSF, or miscellaneous fluids/tissues.
WHICH
TEST IS BEST?
Lyme Disease is very
complicated to diagnose because:
- Lyme bacteria are
not always detectable in the whole blood, even in active disease. The
bacteria like to hide.
- Every patient responds
differently to an infection.
- Antibodies may only
be present for a short time.
For patients with clinical
symptoms of Lyme Disease who test negative by the IgG or IgM Western Blot,
the Whole Blood PCR or the LDA/Multiplex PCR Panel on urine may be appropriate.
There are physician-developed antibiotic protocols to enhance the sensitivity
of the LDA. In addition, there seems to be increased sensitivity of this
test during the start of menses.
Lyme Disease Tests
IgG/IgM and IgM Antibody
Serology
IgG Western Blot and IgM Western Blot
Lyme Dot Blot Assay (LDA)
Reverse Western Blot (Confirmation test for LDA)
Multiplex PCR for urine, whole blood, serum, CSF, miscellaneous (ex: Skin
biopsy, breast milk, semen)
In
addition to Lyme Disease, a co-infection may be suspected for Babesiosis,
Ehrlichiosis, or Bartonella. We offer tests for these other tick-borne illnesses.
The tests are IFA (fluorescent antibody) or direct tests by PCR. In the
case of Babesia, FISH (fluorescent in situ hybridization) is also available.
The FISH test detects the ribosomal RNA of the Babesia parasites directly
on air-dried blood smears. This test is highly specific for Babesia, unlike
the standard test, the geimsa stain smear, which cannot differentiate between
malaria parasites and Babesia.
Babesiosis Tests
B. Microti and/or
WA-1 IgG/IgM Antibody
Babesia and/or
Babesia WA-1 PCR
Babesia FISH
(RNA)
Ehrlichiosis Tests
Human Granulocytic
Ehrlichia IgG/IgM Antibody
Human Granulocytic
Ehrlichia PCR
Human Monocytic
Ehrlichia IgG/IgM AntibodyHuman Monocytic Ehrlichia PCR
Bartonella Tests
Bartonella henselae
PCR with Whole Blood
TICK
TESTING IS ALSO AVAILABLE FOR
Lyme, Babesia
microti, Babesia WA-1, Ehrlichia, and Bartonella
henselea by PCR.
Patients with neurological
symptoms of Lyme disease may need to have a spinal tap in order to study
“the blood of the brain,” the CSF (cerebral spinal fluid). These
patients may have negative blood and urine tests and show positive results
with CSF. The Western blot, LDA, and PCR can be performed on CSF.
WHAT
IS THE TREATMENT?
It is reported that
Lyme disease can be treated success fully with antibiotics if caught early
in the infection. Prevention is the best cure for re-infection. Patients
whose disease is caught later often need to be on antibiotics for longer
periods of time. There is controversy between physicians as to how long
and what is the best mode of treatment. Ehrlichiosis is often treated with
many of the same antibiotics used for Lyme disease. The best treatment for
Babesia is still being explored. Many physicians believe that they
need to treat the Babesiosis before treating Lyme disease to achieve clinical
success.
CAN
LYME DISEASE BE PREVENTED?
Wear long sleeve shirts
and long pants when going into tick country. Light colors are best —
ticks can be seen easier. Tuck pants into socks and spray the clothes with
a known tick repellent. After being in a tick area, check skin and all hair
areas completely. Promptly remove all ticks after being in an area known
to harbor Lyme ticks. Check pets carefully: they are a source of entry for
ticks into the house. Deer hunters need to spend extra time checking their
gear before bringing it into autos and home.
HOW
DO YOU REMOVE A TICK?
- Use tweezers or
forceps.
- Grasp the tick mouthparts
close to the skin.
- Avoid squeezing
the tick which may spread infected body fluids.
- Pull the tick straight
out. Do not twist. Do not attempt to burn the tick.
- Save the tick (you
may want to have it tested for B. burgdorferi or other infectious agents)
- Wash your hands
with soap and water.
- Apply antiseptic
to bite site.
JULY 2002
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