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Description
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Gouty arthritis (acute joint inflammation) is caused by
uric acid (urate) crystals that are deposited in joint
tissue.
The tendency to develop gout and an elevated blood urate
level (hyperuricaemia) is often inherited.
Gout can be caused by excess alcohol use, high blood
pressure, medication, and kidney problems. However it is a
myth that all gout sufferers drink alcohol.
Attacks of gout can be precipitated by injury, fever,
dehydration, overeating, certain foods, alcohol ingestion,
and surgery.
Gout is diagnosed by the presence of urate crystals in
joint fluid and soft tissues.
Treating an acute attack of gout differs from treatment
of hyperuricaemia.
What is gout?
Gout is a metabolic disorder that may be inherited. It is
characterised by recurrent acute joint inflammation (gouty
arthritis) in the extremities, caused by crystals that are
deposited in and around the joints. These crystals come from
body fluids that contain markedly high concentrations of
uric acid (urate), a waste product of digestion that is
normally excreted in urine.
Symptoms include heat, red and shiny ski n, and extreme
tenderness and pain in the affected joints. It tends to
affect the peripheral joints, most often those in the big
toe, but can also affect the knees, elbows, thumbs or
fingers.
The arthritis may become chronic and cause joint
deformity. Tophi – small, hard lumps of urate deposits – may
also form around the ankles, hands, tips of the elbows and
earlobes. The tophi may erupt, causing a discharge.
Collection of urate crystals in the kidneys can lead to
kidney stones.
Not all persons with high urate levels in their blood (hyperuricaemia)
develop gout, but the greater the degree and duration of
hyperuricaemia, the greater the risk of crystal deposition
and acute gout attacks. Gout is a common disease and one of
the oldest in medical literature. One of the oldest drugs in
therapeutics, colchicine, is used for the symptoms of gout.
What causes gout?
Urate is normally steadily excreted with the urine. In some
people the mechanism to excrete the uric acid is defective.
These people are known as under-excretors, and constitute
the majority of gout sufferers. This is aggravated by
certain medications, especially diuretics and kidney
disease. It occurs commonly in the setting of people with
heart disease, obesity and diabetes.
Hyperuricaemia may also be caused by blood conditions
such as lymphoma, leukaemia and haemolytic anaemia (where
blood cells are destroyed), and by other cancers or
psoriasis. In this situation the problem is over-production
and the patients are called over-producers.
If urate levels in the blood rise too high (hyperuricaemia)
the urate starts to crystallise as needle-like crystals in
the joint fluid (synovial fluid) and joint lining (synovial
lining). It forms deposits where the temperature is lower,
as it is in the extremities, particularly around the big
toe.
Some foods may contribute to high blood levels of urate.
Marked rises in urate often follow overindulgence in rich
foods, especially if alcoholic beverages are also consumed.
In most cases. alcohol does not contain uric acid, but makes
the liver produce more from the body’s own supply.
Urate can also form small, plate-like crystals in the
kidneys, where they may aggregate to form gravel or stones.
Intense joint inflammation occurs when white blood cells
engulf the crystals.
In order for this to occur there is often a precipitating
event. Known precipitating factors for gout attacks include
acute infection, emotional upset, the use of diuretic drugs
such as Furosemide or Lasix, surgery and trauma. In fact any
“change” in the daily routine of a patient can precipitate
an attack. This includes a food or alcohol binge. But even a
new reducing diet can aggravate the onset of an attack.
What are the symptoms?
Acute gouty arthritis
- Sudden onset of intense pain in a joint, typically
the big toe, sometimes also the ankle, knee, elbow or
wrist.
- The onset can be almost immediate or over minutes to
hours.
- Swelling, inflammation and a feeling that the joint
is very hot.
- Tense, warm, shiny red or purplish overlying skin.
- Occasionally, in extreme cases, chills and fever.
Although gout is probably inborn, the first attack of
gouty arthritis usually does not appear until middle age,
mainly in men. The first few attacks may come (often at
night) and go without apparent reason, but are often
precipitated by the factors above. The symptoms usually
settle down within days. With prompt treatment, the pain and
inflammation can be brought under control quickly, although
attacks can recur if the underlying problem, a high urate
level, is not treated. Later untreated attacks may persist
for weeks.
Chronic joint symptoms
- Asymptomatic intervals tend to become shorter as the
disease progresses. Attacks start to occur more
frequently and may start to develop in more than one
joint and in unusual sites including knees, hands and
elbows.
- Joints can become permanently deformed as a result
of erosion by the crystals, so that hands and feet lose
their mobility. In rare cases, the shoulder, chest
joints or neck vertebrae may be involved.
Tophi
- When gout has been present for a longer period,
urate deposits called tophi develop. They appear as
small, hard lumps around ankles, hands, the tips of the
elbows, earlobes and even around the vocal chords and
the spinal chord.
- Eventually they can cause pain or stiffness.
- They can also protrude and finally erupt, causing a
discharge of chalky material containing urate crystals.
- Neglected tophi cause damage to the underlying bone
and joints and are an absolute indication to treat the
underlying condition and not just the symptoms of the
attacks.
Prevalence
Gout occurs mainly in middle-aged men, who represent 90 of
all gout sufferers. Often they are obese and suffer from
high blood pressure (hypertension). The remainder are
usually post-menopausal women; gout is rare in children.
Course
Generally, because gout is such a painful affliction, people
seek help and receive treatment. If the diagnosis is made
early, current therapy can permit a normal life. However, if
treatment is not followed or urate levels remain high, the
disease can eventually cause serious joint afflictions and
kidney problems.
For those with advanced disease, it is possible to
correct joint structure to a degree. Tophi can be resolved,
joint function improved, and kidney problems stopped.
About 10 to 20% of gout sufferers develop kidney stones.
These may lead to obstruction and infection, which may
damage kidney tissue. Many people with gout have high blood
pressure. This condition can also damage the kidneys. In
these cases, progressive destruction of kidney tissue may
lead to further problems with urate excretion, which further
raises urate levels.
When gout appears before the age of 30 it tends to be
more severe.
Risk factors
- Genetic predisposition for an abnormality in
handling urate accounts for approximately half of all
cases. A family history of gout can be a risk factor.
- Male sex in middle age
- High blood pressure
- Drugs: thiazide diuretics, aspirin, tuberculosis
medication (pyrazinamide and ethambutol)
- Obesity or excessive weight gain, especially in
youth
- Moderate to heavy alcohol intake
- Abnormal kidney function
- A Western lifestyle
- Underlying diseases with a high turnover of cells
(cancers – especially blood cancers and haemolytic
anaemia)
The following conditions can trigger gout:
- Recent surgery
- Dehydration
- Joint injury
- Excessive dining
- Heavy alcohol intake
- Stress
- Change in diet
- Certain foods such as red meat and rich foods.
When to see a doctor
Call your doctor if:
- Joint pain develops suddenly, especially when there
has been no physical injury and if the pain is
associated with redness and extreme tenderness.
- Joint pain recurs or lasts more than a few days,
especially when associated with chills or fever
(rheumatoid arthritis needs to be excluded).
- When, in known gout, symptoms become more severe or
side effects of medication (allopurinol or colchicine)
occur.
- When any severe colicky back pains develop and
radiate into the groin – this may be caused by a kidney
stone.
- If you are developing lumps (tophi).
- If attacks are more frequent or if they are
affecting different or multiple joints.
- If the attacks are frequent and not settling and /
or tophi are developing, consider asking your doctor
regarding a specialist.
Visit preparation
It is important that the doctor gets the relevant history of
the episode. All medication taken should be known by name
and dosage, as some drugs can cause a gout attack. If gout
has been present for a while, old X-rays related to the
illness may be useful in follow-up.
Diagnosis
- You should see a doctor for any kind of joint pain
to get an accurate diagnosis.
- The history is important and can lead to a diagnosis
by itself. Gout usually presents in one joint at a time,
while other arthritic conditions, such as systemic lupus
and rheumatoid arthritis, usually involves multiple
joints simultaneously.
- A thorough examination can confirm the suspicion of
gout.
- Blood tests may support the diagnosis by showing
high urate levels, but these levels are also sometimes
elevated in the absence of gout. Equally, the uric acid
in the blood may be normal in some cases of acute gout.
The diagnosis is a clinical one in many cases, made from
the history and the examination and special tests may be
normal.
- A definite diagnosis can be made if the
needle-shaped urate crystals are found in tissue or
joint fluid. A small part of suspected tissue (for
example, one of the tophi) is biopsied (removed) under
local anaesthetic. Alternatively, a sample of fluid is
removed from the affected joint, which can be quite
painful, but provides useful information. The material
is examined under the microscope to look for crystals. A
special polarised light microscopy technique is used to
see the crystals.
- X-rays can show punched-out lesions in the bone just
underneath the cartilage of the joint, commonly in the
joint of the big toe. Tophi may also be seen on X-rays.
How is it treated?
General
When you seek treatment for an acute gout attack, your
doctor’s main treatment objectives will be:
- Termination of the acute attack and relief of pain
- Prevention of recurrent attacks (if they are
frequent) by daily prophylactic use of medication
- Prevention of further deposition of urate crystals
and resolution of existing tophi (achieved by lowering
the urate levels in body fluids)
A preventative maintenance programme should be followed
to avert the erosion of bone and joint cartilage, and kidney
damage. Underlying obesity, high blood pressure and high
cholesterol levels should be controlled.
Home
When you wake up with an acute episode, ibuprofen or any
other anti-inflammatory drug in the home pharmacy might
help.
- Rest and elevate the inflamed joint to ease some
discomfort.
- Ice-pack applications can help reduce pain and
decrease inflammation.
- Paracetamol and codeine are not very effective, and
aspirin might make the condition worse because it
prevents excretion of urate by the kidneys.
- Consult a doctor the next morning or, if the pain is
excruciating, go to an emergency department.
- During an acute attack or when under treatment by a
doctor, drink fluids abundantly to combat dehydration,
increase fluid in the kidneys and dilute urate in the
urine.
Medication
In many cases, prompt treatment with appropriate drugs
solves the problem permanently. However, since recurring
attacks are possible, chronic sufferers may have to remain
on low-level drug therapy for extended periods, sometimes
for life.
Acute attacks
- Colchicine: There is usually a dramatic response to
oral colchicine. Joint pain generally begins to subside
after 12 hours of treatment and is gone within 36 to 48
hours. Colchicine may have unfavourable interactions
with antidepressants, tranquillisers or antihistamines;
it is contra-indicated in pregnancy because of the risk
of birth defects.
- Nonsteroidal anti-inflammatory drugs: Ibuprofen (Brufen),
indomethacin (Indocid), naproxen (Naprosyn), piroxicam
and sulindac are effective in acute attacks of
established gout. These drugs should be taken with food,
as they can erode the lining of the stomach. Of note is
that stomach ulcers can develop irrespective of the
route of administration of anti-inflammatory drugs.
Therefore a stomach ulcer can still develop if an
injection or even topical route is used. Care should be
taken in elderly people, especially those with kidney
problems. Newer drugs called COXIBS can be used
especially when there is concern regarding stomach ulcer
problems.
- Corticosteroids: This group, which includes
prednisone, consists of powerful anti-inflammatory
agents that can be used in the treatment of acute gout.
The drugs can be administered orally or injected
directly into the inflamed joint. Corticosteroids can be
prescribed to patients who have accompanying kidney,
liver, or gastrointestinal problems. Long-term chronic
use of corticosteroids is discouraged because of serious
long-term side effects. However, they remain very useful
for severe and resistant cases.
Chronic elevated blood urate levels
- Drugs that block urate production: Allopurinol
reduces urate formation. It is very useful in the
management of repeated episodes of urate kidney stones.
However, there is a risk of side effects that include a
rash, liver damage, mild gastrointestinal problems,
decreased numbers of white blood cells, drowsiness and
disorientation. Allopurinol can interact with other
medications, especially anticoagulants and diuretics.
- Absolute compliance is required when taking
allopurinol. Erratic use will increase gout attacks.
Even stopping for a day might bring on an attack. Once
on the drug, it is usually “forever” as stopping the
drug will simply restart the cycle of increasing
attacks.
- Urinary alkalinisers: Sodium bicarbonate and
trisodium citrate can be used with great success to
prevent kidney stones. These medications do not treat
the actual gout itself.
Important: Drugs that lower the urate concentration
should only be started after the acute symptoms have settled
down completely. If started when the attack is still active,
or even if there is mild residual heat in the joint, these
medications can worsen an acute attack. If the person is
already taking these drugs and has a breakthrough attack,
then the advice is to continue the allopurinol. DO NOT STOP
IT. Rather treat the attack but maintain the allopurinol.
The allopurinol should only be stopped if the attack becomes
resistant and will not settle down.
An increased dose of urate-lowering medications can
precipitate gout attacks in some people. In these cases, low
doses of colchicine or anti-inflammatory can be given to
prevent the development of acute gout.
Surgery
- Withdrawal of fluid from the affected joint (arthrocentesis)
may help, and often corticosteroids can be injected into
the joint space at the same time. (In addition, the most
reliable way of making an accurate diagnosis is to
examine the aspirated fluid under the microscope.)
- Surgical removal of tophi is occasionally done, but
MUST be accompanied by medical treatment or they will
simply re-grow.
- Extracorporal lithotrypsy can help destroy large
kidney stones. During this procedure, shock waves are
transmitted through the body and focussed on the kidney
stone. The stone is cracked up into small pieces that
can be passed normally in the urine. It might be
necessary to remove the stones in an operation if this
fails.
Prevention
- Avoid certain protein-rich foods that can lead to
decreased urate excretion: organ meats (liver, brains
and kidneys), shellfish, fatty fish, asparagus, spinach
and most dried beans. Some people find particular foods
which affect them as individuals. These should be
avoided in that instance.
- Increase your fluid intake – this is very important
to decrease the possibility of urate crystal formation
in the kidney tracts.
- Avoid alcohol, as it retards elimination of urate.
- If you are obese, control your body weight.
If you are a man and gouty arthritis runs in your family,
these preventative measures are particularly important.
Blood and urine tests during routine check-ups will alert
your doctor to a potential for gout attacks. He or she may
prescribe drugs to reduce the body's production of urate and
to encourage the excretion of excess urate. It is a
treatable disease.
Reviewed by Dr David Gotlieb, rheumatologist, MBChB
FCP(SA).
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