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Lyme Disease
MAJOR
RECOMMENDATIONS -
Highlights of
Guidelines
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Since there is
currently no definitive test for
Lyme disease, laboratory results should not be used to
exclude an individual from treatment.
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Lyme disease is a clinical
diagnosis and tests should be used to support rather than
supersede the physician’s judgment.
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The early use of
antibiotics can prevent persistent, recurrent, and refractory
Lyme disease.
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The duration of
therapy should be guided by clinical response, rather than by
an arbitrary (i.e., 30 day) treatment course.
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The practice of
stopping antibiotics to allow for delayed recovery is not
recommended for persistent Lyme
disease. In these cases, it is reasonable to continue
treatment for several months after clinical and laboratory
abnormalities have begun to resolve and symptoms have
disappeared.
Diagnostic Concerns - The most important method for
preventing chronic Lyme
disease is recognition of the early manifestations of the
disease.
Atypical
Early Presentations
Early
Lyme disease classically
presents with a single erythema migrans (EM or "bull’s-eye")
rash. The EM rash may be absent in over 50% of
Lyme disease cases, however.
Patients should be made aware of the significance of a range of
rashes beyond the classic EM, including multiple, flat, raised,
or blistering rashes. Central clearing was absent in over half
of a series of EM rashes. Rashes can also mimic other common
presentations including a spider bite, ringworm, or cellulitis.
Physicians should
be aware that fewer than 50% of all
Lyme disease patients recall a tick bite. Early
Lyme disease should also be
considered in an evaluation of "off-season" onset when flu-like
symptoms, fever, and chills occur in the summer and fall. Early
recognition of atypical early Lyme
disease presentation is most likely to occur when the patient
has been educated on this topic.
New Chronic
Lyme Disease
Presentations
A detailed
history may be helpful for suggesting a diagnosis of chronic
Lyme disease. Headache,
stiff neck, sleep disturbance, and problems with memory and
concentration are findings frequently associated with neurologic
Lyme disease. Other clues to
Lyme disease have been
identified, although these have not been consistently present in
each patient: numbness and tingling, muscle twitching,
photosensitivity, hyperacusis, tinnitus, lightheadedness, and
depression.
Most patients
diagnosed with chronic Lyme
disease have an indolent onset and variable course. Neurologic
and rheumatologic symptoms are characteristic, and increased
severity of symptoms on wakening is common. Neuropsychiatric
symptoms alone are more often seen in chronic than acute
Lyme disease. Although many
studies have found that such clinical features are often not
unique to Lyme disease, the
striking association of musculoskeletal and neuropsychiatric
symptoms, the variability of these symptoms, and their recurrent
nature may support a diagnosis of the disease.
The
Limitations of Physical Findings
A comprehensive
physical examination should be performed, with special attention
to neurologic, rheumatologic, and cardiac symptoms associated
with Lyme disease.
Physical findings
are nonspecific and often normal, but arthritis, meningitis, and
Bell’s palsy may sometimes be noted. Available data suggest that
objective evidence alone is inadequate to make treatment
decisions, because a significant number of chronic
Lyme disease cases may occur
in symptomatic patients without objective features on
examination or confirmatory laboratory testing.
Factors other
than physical findings, such as a history of potential exposure,
known tick bites, rashes, or symptoms consistent with the
typical multisystem presentation of
Lyme disease, must also be considered in determining
whether an individual patient is a candidate for antibiotic
therapy.
Sensitivity
Limitations of Testing
Treatment
decisions should not be based routinely or exclusively on
laboratory findings. The two-tier diagnostic criteria, requiring
both a positive enzyme-linked immunosorbent assay (ELISA) and
western blot, lacks sensitivity and leaves a significant number
of individuals with Lyme
disease undiagnosed and untreated. These diagnostic criteria
were intended to improve the specificity of tests to aid in
identifying well-defined Lyme
disease cases for research studies. Though arbitrarily chosen,
these criteria have been used as rigid diagnostic benchmarks
that have prevented individuals with
Lyme disease from obtaining
treatment. Diagnosis of Lyme
disease by two-tier confirmation fails to detect up to 90% of
cases and does not distinguish between acute, chronic, or
resolved infection.
The Centers for
Disease Control and Prevention (CDC) considers a western blot
positive if at least 5 of 10 immunoglobulin G (IgG) bands or 2
of 3 immunoglobulin M (IgM) bands are positive. However, other
definitions for western blot confirmation have been proposed to
improve the test sensitivity. In fact, several studies showed
that sensitivity and specificity for both the IgM and IgG
western blot range from 92 to 96% when only two specific bands
are positive.
Lumbar puncture
has also been disappointing as a diagnostic test to rule out
concomitant central nervous system infection. In
Lyme disease, evaluation of
cerebrospinal fluid is unreliable for a diagnosis of
encephalopathy and neuropathy because of poor sensitivity. For
example, pleocytosis was present in only one of 27 patients
(sensitivity 3%) and with only seven cells. The antibody index
was positive (>1) in only one of 27 patients (sensitivity 3%).
An index is the ratio between Lyme
ELISA antibodies in the spinal fluid and
Lyme ELISA antibodies in the
serum. The proposed index of 1.3 would be expected to have even
worse sensitivity.
Several
additional tests for Lyme
disease have been evaluated. These include antigen capture,
urine antigen, and polymerase
chain reaction. Each has advantages and disadvantages in terms
of convenience, cost, assay standardization, availability, and
reliability. These tests remain an option to identify people at
high risk for persistent, recurrent, and refractory
Lyme disease but have not
been standardized.
Seronegative
Lyme Disease
A patient who has
tested seronegative may have a clinical presentation consistent
with Lyme disease,
especially if there is no evidence to indicate another illness.
Although many
individuals do not have confirmatory serologic tests,
surveillance studies show that these patients may have a similar
risk of developing persistent, recurrent, and refractory
Lyme disease compared with
the seropositive population.
Continued
Importance of Differential Diagnosis
The differential
diagnosis of Lyme disease
requires consideration of both infectious and noninfectious
etiologies. Among noninfectious causes are thyroid disease,
degenerative arthritis, metabolic disorders (vitamin B12
deficiency, diabetes), heavy metal toxicity, vasculitis, and
primary psychiatric disorders.
Infectious causes
can mimic certain aspects of the typical multisystem illness
seen in chronic Lyme
disease. These include viral syndromes, such as parvovirus B19
or West Nile virus infection, and bacterial mimics, such as
relapsing fever, syphilis, leptospirosis, and mycoplasma.
The clinical
features of chronic Lyme
disease can be indistinguishable from fibromyalgia and chronic
fatigue syndrome. These illnesses must be closely scrutinized
for the possibility of etiological Borrelia burgdorferi
infection.
Clinical
Judgment
Clinical judgment
remains necessary in the diagnosis of late
Lyme disease. A problem in
some studies that relied on objective evidence was that
treatment occurred too late, leaving the patient at risk for
persistent and refractory Lyme
disease.
As noted,
time-honored beliefs in objective findings and two-tier
serologic testing have not withstood close scrutiny.
Lyme disease should be
suspected in patients with newly acquired or chronic symptoms
(headaches, memory and concentration problems, and joint pain).
Management of patients diagnosed on the basis of clinical
judgment needs to be tested further in prospective trials, and
diagnostic reproducibility must be verified.
Testing for
Coinfection
Polymicrobial
infection is a new concern for individuals with
Lyme disease, and
coinfection is increasingly reported in critically ill
individuals. Although B. burgdorferi remains the most
common pathogen in tick-borne illnesses, coinfections including
Ehrlichia and Babesia strains are increasingly
noted in patients with Lyme
disease, particularly in those with chronic illness.
Bartonella is another organism that is carried by the same
ticks that are infected with B. burgdorferi, and
evidence suggests that it is a potential coinfecting agent in
Lyme disease.
Recent animal and
human studies suggest that Lyme
disease may be more severe and resistant to therapy in
coinfected patients. Thus, concurrent testing and treatment for
coinfection is mandatory in Lyme
disease patients.
Treatment
Considerations: Since
Lyme disease can become persistent, recurrent, and
refractory even in the face of antibiotic therapy, evaluation
and treatment must be prompt and aggressive.
Prompt Use of
Antibiotics- Although no well designed studies have
been carried out, the available data support the prompt use of
antibiotics to prevent chronic Lyme
disease. Antibiotic therapy may need to be initiated upon
suspicion of the diagnosis, even without definitive proof.
Neither the optimal antibiotic dose nor the duration of therapy
has been standardized, but limited data suggest a benefit from
increased dosages and longer treatment, comparable to the data
on tuberculosis and leprosy which are caused by similarly
slow-growing pathogens.
Choosing an
Antibiotic - In acute
Lyme disease, the choice of antibiotics should be
tailored to the individual and take into account the severity of
the disease as well as the patient’s age, ability to tolerate
side effects, clinical features, allergy profile, comorbidities,
prior exposure, epidemiologic setting, and cost.
Conversely,
persistent and refractory Lyme
disease treatment is more likely to include intravenous and/or
intramuscular antibiotics. The choices depend in part on the
patient’s response to antibiotic therapy and on the success of
antibiotics in treating other Lyme
disease patients.
Therapy usually
starts with oral antibiotics, and some experts recommend high
dosages. The choice of antibiotic therapy is guided by weighing
the greater activity of intravenous antibiotics in the central
nervous system against the lower cost and easy administration of
oral antibiotics for B. burgdorferi.
Oral
Antibiotic Options - For many
Lyme disease patients, there
is no clear advantage of parenteral therapy. Along with cost
considerations and pressure to treat patients with
Lyme disease with the least
intervention, there is growing interest in the use of oral
therapy.
First-line drug
therapies for Lyme disease
may include (in alphabetical order): oral amoxicillin,
azithromycin, cefuroxime, clarithromycin, doxycycline, and
tetracycline. These antibiotics have similar favorable results
in comparative trials of early Lyme
disease.
Intravenous
Antibiotic Options - It is common
practice to consider intravenous antibiotics upon failure of
oral medications in patients with persistent, recurrent, or
refractory Lyme disease, and
as the first line of therapy for certain conditions, (i.e.,
encephalitis, meningitis, optic neuritis, joint effusions, and
heart block).
Ideally, the
intravenous antibiotic should be selected on the basis of in
vitro sensitivity testing or clinical experience. Intravenous
antibiotics are also justified by concern for penetration into
the central nervous system.
Until recently,
ceftriaxone, cefotaxime, and penicillin were the only
intravenous antibiotics routinely studied for use in
Lyme disease. Intravenous
imipenem, azithromycin, and doxycycline have an adequate
antispirochetal spectrum of activity and may represent suitable
alternative therapies. However, the latter two drugs are often
considered for intravenous use only if they are not tolerated
orally.
Intramuscular
Antibiotic Options - Intramuscular
benzathine penicillin (1.2 to 2.4 million units per week) is
sometimes effective in patients who do not respond to oral and
intravenous antibiotics. If intramuscular benzathine penicillin
is used, long-term therapy may be necessary due to the low serum
concentration of this form of penicillin. Benzathine penicillin
has mainly been used in patients who have had multiple relapses
while receiving oral or intravenous antibiotic therapy or who
are intolerant of oral or intravenous antibiotics.
Combination
Antibiotic Treatment - Combination therapy
with two or more antibiotics is now increasingly used for
refractory Lyme disease and
has also been given as initial therapy for some chronic
presentations.
This approach is
already used for another tick-borne illness, babesiosis. Oral
amoxicillin, cefuroxime, or (more recently) cefdinir combined
with a macrolide (azithromycin or clarithromycin) are examples
of combination regimens that have proven successful in clinical
practice, although controlled clinical trials are lacking in
persistent, recurrent, and refractory
Lyme disease.
Combination
therapy in patients with Lyme
disease raises the risk of adverse events. This risk must be
weighed against the improved response to combination therapy in
Lyme disease patients
failing single agents.
Sequential
Treatment - Clinicians increasingly use the sequence of an
intravenous antibiotic followed by an oral or intramuscular
antibiotic. In two recent case series that employed combination
therapy and sequential therapy, most patients were successfully
treated. A logical and attractive sequence would be to use
intravenous therapy first (e.g., intravenous ceftriaxone), at
least until disease progression is arrested and then follow with
oral therapy for persistent and recurrent
Lyme disease.
Dosage -
Increasingly, clinicians recommend that certain drugs used for
Lyme disease be given at
higher daily doses: for example, 3,000–6,000 mg of amoxicillin,
300–400 mg doxycycline, and 500–600 mg of azithromycin. Some
clinicians prescribe antibiotics using blood levels to guide
higher doses. Close monitoring of complete blood counts and
chemistries are also required with this approach.
With higher
doses, there may be an increase in adverse events in general and
gastrointestinal problems in particular. Acidophilus has
reportedly reduced the incidence of Clostridium difficile
colitis and non-C. difficile antibiotic-related
diarrhea.
Serious adverse
effects of antibiotics, however, were less common than previous
estimates. In a recent clinical trial of chronic
Lyme disease, the overall
serious adverse event rate was 3% after three months of
antibiotics, including 1 month of intravenous antibiotics.
Clinicians who have experience with higher dose antibiotic
therapy must balance the benefit of higher drug levels achieved
with this therapy against the modest risk of gastrointestinal
and other side effects.
Duration of
Therapy - Because of the disappointing long-term outcome
with shorter courses of antibiotics, the practice of stopping
antibiotics to allow for a delayed recovery is no longer
recommended for patients with persistent, recurrent, and
refractory Lyme disease.
Reports show failure rates of 30–62% within 3 years of
short-course treatment using antibiotics thought to be effective
for Lyme disease. Conversely
for neurologic complications of
Lyme disease, doubling the length of intravenous
ceftriaxone treatment from 2 to 4 weeks improved the success
rate from 66 to 80%.
The management of
chronic Lyme disease must be
individualized, since patients will vary according to severity
of presentation and response to previous treatment.
Concurrent risk
factors (i.e., coinfections, previous treatment failures,
frequent relapses, neurologic involvement, or previous use of
corticosteroids) or evidence of unusually severe
Lyme disease should lead to
the initiation of prolonged and/or intravenous antibiotic
treatment. Physicians should always assess the patient’s
response to treatment before deciding on appropriate duration of
therapy (i.e., weeks versus months).
Empiric
Treatment - The importance of establishing the diagnosis of
Lyme disease is heightened
in light of increasing concern about antibiotic overuse. After
an appropriate history, physical examination, and laboratory
testing are completed, empiric antimicrobial therapy should be
initiated on the basis of clinical clues, the severity of the
patient’s acute illness, underlying disease, and the likelihood
of B. burgdorferi infection. The International
Lyme and Associated Diseases
Society (ILADS) working group recommends that empiric treatment
be considered routine for patients with a likely diagnosis of
Lyme disease.
Persistent
Lyme Disease
- Persistent Lyme
disease is more resistant to treatment and more likely to
produce a relapse. Although persistent
Lyme disease may resolve
without additional therapy, many experts believe that this
condition should be treated with repeated and prolonged
antibiotics. Physicians should extend the duration of
antibiotics to prevent or delay recurrent and refractory
Lyme disease.
Recurrent
Lyme Disease
- Despite previous antibiotic treatment,
Lyme disease has a
propensity for relapse and requires careful follow-up for years.
The data suggest that failure to eradicate the organism may be
the reason for a recurrence of symptoms. Early and aggressive
treatment with antibiotics is indicated for recurrent
Lyme disease. The ultimate
impact from retreating each episode of recurrent
Lyme disease is currently
unclear.
Refractory
Lyme Disease
Refractory
Lyme disease is a
devastating condition that usually affects patients with
persistent symptomatology and long-term disability. Prompt and
aggressive institution of antibiotic therapy may be essential to
prevent refractory disease. Increasing evidence shows that
antibiotics have a beneficial effect on the course of refractory
Lyme disease even in cases
where the patient is intolerant of antibiotics or when a
previous regimen has failed. Several months of therapy are often
required to produce clear evidence of improvement. During this
time, symptomatic treatment may be combined with antibiotic
treatment.
Treatment
Failure - When patients fail to respond or their conditions
deteriorate after initiation of empiric therapy, a number of
possibilities should be considered other than Jarisch-Herxheimer
reaction. These include adverse events that limit treatment,
allergic history to medication, inappropriate or inadequate
dosing regimen, compliance problems, incorrect medication,
immune sequelae, and sequestering of the organism (e.g., in the
central nervous system). An alternative diagnosis or coinfection
should also be considered.
Symptomatic
Treatment - Although there may be a potential role for
symptomatic treatment in chronic
Lyme disease, this approach has little support due to the
strong possibility of persistent infection. Owing to the
potential hazard of immunosuppression and the poor outcome in
one study, steroid therapy is not recommended. Surgical
synovectomy is associated with significant morbidity and does
not address neurologic presentations; it should be reserved for
knee pain failing antibiotic treatment. Intra-articular steroid
injection may be useful as a temporizing procedure in patients
with persistent knee pain but this runs the risk of masking
persistent infection.
Symptomatic
therapy (particularly anti-inflammatory medications, tricyclic
antidepressants, selective serotonin re-uptake inhibitors, and
hydroxychloroquine) may be useful in concert with antibiotics
and in individuals failing antibiotics.
Hyperbaric oxygen
therapy (HBOT) is under study but is not recommended for routine
therapeutic use. Other treatments, including cholestyramine (CSM),
antifungal therapy, and antiviral agents require further study.
Since patients
are becoming more interested in alternative therapies (e.g.,
traditional Chinese medicine, anti-oxidants, hyperthermia, bee
venom, naturopathy and homeopathy), physicians should be
prepared to address questions regarding these topics.
Fibromyalgia
- The outcome of treating fibromyalgia secondary to
Lyme disease with
nonantibiotic regimens has been poor. The most encouraging
clinical trial showed success in only one of 15 patients and
only modest improvement in 6 of 15 individuals with fibromyalgia
despite 2 years of treatment.
Antibiotic
therapy has been much more effective than supportive therapy in
symptomatic patients with fibromyalgia secondary to
Lyme disease.
Fibromyalgia
treatment alone without antibiotics raises the risk of
conversion to refractory chronic
Lyme disease and/or exacerbation of an undiagnosed
persistent infection and is not recommended. Increasingly,
clinicians do not feel comfortable treating fibromyalgia in
Lyme disease without
antibiotics.
Decision to
Stop Antibiotics
Several studies
of patients with Lyme
disease have recommended that antibiotics be discontinued after
30 days of treatment. Complicating the decision to stop
antibiotics is the fact that some patients present with disease
recurrence after the resolution of their initial
Lyme disease symptoms. This
is consistent with incomplete antibiotic therapy. Although the
optimal time to discontinue antibiotics is unknown, it appears
to be dependent on the extent of symptomatology, the patient’s
previous response to antibiotics, and the overall response to
therapy (see below).
Rather than an
arbitrary 30-day treatment course, the patient’s clinical
response should guide duration of therapy. Patients must
therefore be carefully evaluated for persistent infection before
a decision is made to withhold therapy.
The decision to
discontinue antibiotics should be made in consultation with the
patient and should take into account such factors as the
frequency and duration of persistent infection, frequency of
recurrence, probability of refractory
Lyme disease, gains with
antibiotics, the importance to the patient of discontinuing
antibiotics, and potential for careful follow-up.
The ideal
approach would be to continue therapy for
Lyme disease until the
Lyme spirochete is
eradicated. Unfortunately there is currently no test available
to determine this point. Therefore, the clinician must rely on
the factors outlined above to decide on the length of antibiotic
therapy for chronic Lyme
disease.
Alternative
Antibiotics
There is
compelling evidence that Lyme
disease can result in serious and potentially refractory
illness. Use of alternative antibiotics to treat early
Lyme disease with erythema
migrans is generally not indicated unless coinfection is
suspected.
The ILADS Working
Group believes that the risk of alternative antibiotics is
acceptable in selected Lyme
disease patients presenting with chronic
Lyme disease. Alternative
antibiotics include less commonly used oral antibiotics (cefixime,
cefdinir, metronidazole) and intravenous antibiotics (imipenem,
azithromycin). The role of alternative antibiotics in low-risk
patients is less certain and there is less consensus among the
guideline developers as to whether the potential benefits
outweigh the risks.
Therapy for
Coinfection
Therapy for
polymicrobial infection in Lyme
disease is a rapidly changing area of clinical practice.
Uncomplicated Lyme disease
may be managed without addressing coinfection by means of
standard oral or parenteral antibiotic therapy. Some but not all
experts recommend therapy for subclinical or chronic coinfection
with Ehrlichia, Babesia, or Bartonella
on the basis of their belief that responses are more prompt with
this approach.
The dose,
duration, and type of treatment for coinfections have not been
defined. Published reports of coinfection are limited to a small
number of patients treated in open-label, nonrandomized studies.
Doxycycline has been indicated for Ehrlichia. A
recently published randomized trial determined that treatment of
severe Babesia microti with the combination of
atovaquone and azithromycin was as effective as the use of
standard oral therapy with clindamycin and quinine.
The decision to use alternative antibiotics should be based on
the individual case, including a careful assessment of the
patient’s risk factors and personal preferences. Patients
managed in this way must be carefully selected and considered
reliable for follow-up. Further controlled studies are needed to
address the optimal antimicrobial agents for coinfections and
the optimal duration of therapy. |