Lyme arthritis is caused by a bacterium transmitted by tick bites.
While the skin, the central nervous system, the heart, the eye
and other organs may be the target of infection, in Lyme arthritis,
joints are the exclusive target in most cases. However, there
may be a history of skin involvement in the form of erythema migrans,
an expanding red skin rash at the site of the tick bite.
In rare instances, untreated cases of Lyme arthritis may progress
to central nervous system involvement.
common is it?
Only a minority of children with arthritis have Lyme Arthritis.
However, Lyme arthritis is probably the most frequent arthritis
occurring after bacterial infection in children and adolescents
in Europe. It rarely occurs before the age of four and is mainly
a disease of school children.
It occurs in all areas of Europe. However, it is most prevalent
in Middle Europe and southern Scandinavia around the Baltic Sea.
Transmission depends on the bite of infected ticks active from
April to October, but depending on environmental temperature and
humidity, Lyme arthritis may start at any time during the year,
due to the long and varying times between the tick-bite and the
onset of joint swelling.
are the causes of the disease?
The cause of the disease is the bacterium Borrelium burgdorferi
transmitted via tick bites. Most ticks are not infected and most
tick-bites do not result in infection. Most infections, if apparent
as erythema migrans, do not progress to later stages of the disease,
including Lyme arthritis.
This is the case especially if early stages, including erythema
migrans, have been treated with antibiotics. Although Lyme borreliosis,
in the form of erythema migrans, may occur in up to one in 1000
children each year, the occurrence of Lyme arthritis, the late
manifestation of the disease, is a rare event.
Lyme arthritis is an infectious disease and not inherited. In
addition, chronic Lyme arthritis has been associated with certain
genetic markers, suggesting an inherited predisposition to developing
the disease, but the precise mechanisms are not known.
has my child got this disease? Can it be prevented?
In European regions where ticks are roaming, it is difficult to
prevent kids from acquiring a tick. However, most of the time,
the causative organism Borrelia burgdorferi is not transmitted
immediately after the tick-bite, but only several hours and up
to one and a half days later, when the bacterium has reached the
salivary glands of the tick and is excreted with saliva into the
Ticks attach to their hosts for three to five days feeding on
the host’s blood. When children are screened every evening
in the summer for attached ticks and when these ticks are removed
immediately, transmission of Borrelia burgdorferi is very unlikely.
Preventive treatment with antibiotics after a tick bite is not
However, when the early manifestation erythema migrans occurs,
it should be treated with antibiotics. This treatment will stop
further proliferation of the bacterium and prevent Lyme arthritis.
In the USA, a vaccine against a single strain of Borrelia burgdoferi
has been developed, but was withdrawn from the market for economic
reasons. This vaccine is not useful in Europe due to strain variations.
Although it is an infectious disease, it is not contagious, since
the bacterium must be transported by the tick.
are the main symptoms?
The main symptoms of Lyme arthritis are swelling with effusion
and limitation of movement in affected joint(s). Often the huge
amount of swelling is accompanied by little or no joint pain.
The joint most frequently affected is the knee joint, however,
other large joints and even small joints may be affected. Rarely,
the knee may not be involved at all. Two thirds of cases present
as monarthritis of the knee joint. More than 95 % of cases take
an oligoarticular course (four or less joints), often with a knee
joint as the only remaining inflamed joint after some time. Lyme
arthritis occurs as episodic arthritis in two thirds of cases.
This means that arthritis disappears by itself after several days
to a few weeks and, after an interval without any symptoms, the
arthritis returns in the same joint(s).
The frequency and duration of episodes of joint inflammation usually
decreases with time, but may increase and arthritis may become
chronic in the end. However, rarely, there are also cases with
chronic arthritis from the beginning (duration of arthritis for
three months or longer).
the disease the same in every child?
No. The disease may be acute (i.e. there is a single episode of
arthritis), episodic, chronic (of long duration).
the disease in children different from the disease in adults?
The disease in adults and children is similar. However, children
may have a higher frequency of arthritis than adults. In contrast,
the younger the child, the more rapid the course and the better
the chance of successful antibiotic treatment.
is it diagnosed?
Whenever there is newly appearing arthritis without a known cause,
Lyme arthritis should be considered. The clinical suspicion is
confirmed by laboratory investigation including blood tests and,
in some instances, tests on synovial fluid (joints fluid).
In blood, antibodies against Borrelia burgdorferi may be found
by a test called enzyme immunoassay. If there are IgG-antibodies
to Borrelia burgdorferi found by enzyme immunoassay, a confirmatory
test called Immunoblot or Western blot has to be performed. If
this result confirms the enzyme immunassay findings, Lyme disease
can be confirmed.
The diagnosis may also be confirmed by analysis of synovial fluid,
in which the gene of the bacterium Borrelia burgdorferi may be
found by a technique called polymerase chain reaction. This laboratory
test is difficult to perform and few laboratories are able to
generate valuable results.
Lyme arthritis should be diagnosed by the pediatrician or in a
pediatric hospital. However, if treatment fails, a pediatric specialist
should be involved in the further management of the child.
is the importance of tests?
Apart from serological values, usually inflammatory values are
taken and blood chemistry tests are done. In addition, other infectious
causes of arthritis may be considered and tested by appropriate
Once Lyme arthritis has been confirmed by laboratory values, including
enzyme immunoassay and immuno-blot, it is not useful to repeat
these tests, as they do not indicate response to antibiotic treatment.
These tests may remain highly positive for years in spite of successful
it be treated or cured?
Since Lyme arthritis is an infectious bacterial disease, it can
be treated with antibiotics. More than 80% of patients with Lyme
arthritis are cured after one or two treatments with antibiotics.
In the remaining 10–20% further antibiotic treatment usually
does not cure the disease and anti-rheumatic treatment is necessary.
are the treatments?
Lyme arthritis may be treated by oral antibiotics for four weeks
or intravenous antibiotics for at least two weeks. Since compliance
may be a problem with amoxicilline or doxycycline, intravenous
treatment with ceftriaxon or cefotaxime may be more advantageous.
are the side effects of drug therapy?
Side effects may occur, including diarrhoea, or allergic reactions.
However, most side effects are rare and minor.
long should treatment last for?
After antibiotic treatment has been completed, it is recommended
to wait six weeks before concluding that treatment might not have
cured the disease in the presence of ongoing arthritis.
If this is the case, another antibiotic treatment may be added.
When, six weeks after the completion of the second antibiotic
treatment there is still arthritis, anti-rheumatic drugs should
about unconventional and complementary therapies?
When antibiotic treatment fails, parents may be inclined to try
unconventional remedies as in other rheumatic diseases. There
is no evidence of their efficacy.
kind of periodic check-ups are necessary?
The only useful check-up is examination of the joints. The longer
the period of remission, the less chance there is of a relapse.
long will the disease last for?
More than 80 % of cases disappear after one or two antibiotic
treatments. In the remaining cases, arthritis will disappear over
a course of months to years. Eventually the disease will stop
is the long-term prognosis (predicted course and outcome) of the
After treatment with antibiotics, in most cases the disease will
go away without leaving any consequences. There are individual
cases in whom definite joint damage has occurred, including limited
range of motion and premature osteoarthritis.
it possible to recover completely?
Yes. More than 95% of patients will recover completely.
could the diseases affect the child and family’s daily life?
Due to pain and limitation of motion, the child may have difficulty
in participating in some sporting activities. In most patients
the disease is mild and problems are minor and transient.
For a limited period of time the child might get a suspension
for school sports, indicating that the student should decide on
which activities to take part in.
The child or adolescent should decide on this matter. If the child
takes part in a regular planned programme in a sports club, it
might be advantageous to diminish the requirements of this programme,
or to adapt the requirements.
The diet should be balanced and contain enough proteins, calcium
and vitamins for the growing child. Dietary changes do not affect
the course of the disease.
climate influence the course of the disease?
Although ticks need a warm and humid climate, once the infection
has reached the joints the course of the disease is not influenced
by climatic variations.
the child be vaccinated?
There are no restrictions concerning vaccinations. The success
of vaccination is not affected by the disease, or by antibiotic
treatment. Currently, there is no vaccine against Lyme borreliosis