Gout
This patient information about
gout from MD Consult, give some important details about a disease that affects
many middle-aged men in Kenya.
What Is Gout?
Gout is a type
of arthritis (inflammation of the joints) that mostly affects men age 40 and
older. It is nearly always associated with chronic hyperuricemia, a
long-lasting, abnormally high concentration of uric acid in the blood. The
process leading to gout begins with the metabolism of purines,
nitrogen-containing compounds, that are important for energy. Purines can be
divided into two types, endogenous and exogenous. Endogenous purines are
synthesized within the nuclei of cells in the human body itself, whereas the exogenous
purines are obtained from foods. All mammals, except humans, possess an enzyme
called uricase that breaks purines down into a very soluble product called
allantoin. Humans, however, lack this enzyme, and the end point of their purine
metabolism is uric acid, a useless substance that can build up in tissues in the
body if it is not adequately eliminated in urine.
Uric acid is produced in the liver and enters the bloodstream. Most uric acid
eventually passes through the kidneys and is excreted in the urine; the rest is
disposed of in the intestines, where it is processed and oxidized by bacteria.
Normally these processes keep the concentration of uric acid in the blood plasma
(the liquid part of the blood) below 6.8 milligrams per deciliter (6.8 mg/dL).
Under certain circumstances, however, the body produces too much uric acid or
excretes too little. This results in higher levels and increased concentrations
of uric acid in the blood, and hyperuricemia develops. At normal body
temperature and below, uric acid concentrations increase; as they approach 7 mg/dL,
the blood becomes supersaturated, and needlelike crystals of a salt called
monosodium urate (MSU) form. In time, as MSU crystals accumulate, they cause
inflammation and pain, symptoms typical of gout.
Effects of Hyperuricemia
High levels of
uric acid are basically associated with four conditions, which can occur
independently but may develop one after the other if gout is untreated: acute
gouty arthritis, chronic tophaceous gout, uric acid nephrolithiasis (a form of
kidney stone), and, possibly, uric acid nephropathy (kidney disease).
Acute Gouty Arthritis. Acute gouty arthritis
is the stage at which the first symptoms of gout appear.
Chronic Tophaceous Gout. After several
years, persistent gout can produce tophi, which are solid deposits of MSU
crystals that form in the joints and elsewhere in the body (hence the term
chronic tophaceous gout). Without anti-hyperuricemia treatment, tophi develop on
average about 10 years after the onset of the disease although their first
appearance can range from three to 42 years. Bones, cartilage, tendons, soft
tissue, and membranes containing synovial fluid (the lubricating fluid
surrounding joints) can all harbor tophi. Common locations include the helix of
the outer ear (the curved ridge along the edge of the ear), the fingers, hands,
forearms, knees, and feet, and the olecranon bursa (a sac at the elbow joint
filled with synovial fluid). In some cases, tophi break through the skin and
appear as white or yellowish-white, chalky nodules. (They have been described as
looking like "crabs eyes.") In rare cases, they can settle in regions
around the heart and spine. Today, drug therapy has reduced the prevalence of
chronic tophaceous gout to as little as 3%, although certain groups, such as
transplant patients receiving cyclosporine, still face a high risk of developing
tophi.
Uric Acid Nephrolithiasis (Kidney Stones). Uric
acid nephrolithiasis occurs when kidney stones form from uric acid. Uric acid
and other kidney stones are present in 10% to 25% of patients with primary gout,
a prevalence more than 1000 times that of the general population. In secondary
gout, the reported incidence reaches 42%. Uric acid stones can also form in the
absence of gout or hyperuricemia. Not all of the kidney stones in patients with
gout are composed of uric acid; some are composed of calcium oxalate, calcium
phosphate, or those substances combined with uric acid. Kidney stones can be
extraordinarily painful and can cause infection and kidney failure if untreated.
Chronic Uric Acid Interstitial Nephropathy. Chronic
uric acid interstitial nephropathy occurs when crystals slowly form in the
structures and tubes that carry fluid from the kidney. It is reversible and not
likely to injure the kidneys. (Sudden overproduction of uric acid, however, can
occasionally block the kidneys and cause them to fail. This most often occurs in
conjunction with chemotherapy for leukemia or lymphoma and can also occur after
heat stress from vigorous exercise, following epileptic seizures, and after
corticosteroid therapy for severe allergic reactions.)
What Causes Gout?
Gout is
classified as either primary (the most common type) or secondary, depending on
the cause of the associated hyperuricemia. In both types of gout, between 70%
and 95% of hyperuricemia cases are the result of underexcretion of uric acid,
rather than uric acid overproduction.
Primary Gout
More than 99%
of primary gout cases are referred to as idiopathic, meaning that the cause of
the hyperuricemia cannot be determined. They are most likely due to a
combination of hormonal and genetic factors that cause metabolic abnormalities
resulting in overproduction of uric acid or reduced excretion of uric acid. The
remaining 1% of primary gout cases are traceable to either of two rare inherited
enzyme defects that affect purine synthesis in the cells.
Secondary Gout
In secondary
gout, hyperuricemia is caused by drug therapy or by medical conditions other
than an inborn metabolic disorder that increase uric acid concentration.
Medications. The list of drugs that cause
hyperuricemia is long. They include thiazide diuretics (the "water
pills" used to control hypertension), pyrazinamide (used to treat
tuberculosis), and the immunosuppressive drug cyclosporine (given to transplant
recipients to prevent organ rejection). Low doses of aspirin decrease uric acid
excretion and increase the chance for hyperuricemia; this is a particular
problem for older people with heart disease who would benefit from baby aspirin.
High doses have the opposite effect, however.
Kidney Problems. Renal (meaning kidney)
insufficiency is the impaired ability of the kidneys to eliminate waste
products, including uric acid, which then build up in the blood. It is one of
the major risk factors for gout in older people. Hyperuricemia occurs in between
30% and 85% of people who have kidney transplants and who receive
immunosuppressive and diuretic drugs.
Other Medical Conditions. A number of
diseases, including leukemia, lymphoma, and psoriasis, can cause gout. Over
exposure to lead can cause gout.
Alcohol Use. Alcohol use increases
uric acid levels in three ways: by providing an additional dietary source of
purines (the compounds from which uric acid is formed), by intensifying the
body's production of uric acid, and by interfering with the kidneys' ability to
excrete uric acid.
Purine-Rich Diet. A purine-rich diet rarely
causes hyperuricemia, although it may precipitate an attack in some people with
existing gout. [For a list of purine-rich foods, see What Lifestyle
Measures Can Help Prevent Gout? below.]
What Are The Symptoms Of Gout?
Gout is often
divided into four symptomatic stages: asymptomatic hyperuricemia, acute gouty
arthritis, intercritical gout, and chronic tophaceous gout. Gout symptoms can be
precipitated by stress, infection, joint injury, weight loss, surgery, certain
kinds of drug treatment, overindulgence in alcohol or purine-rich foods, or even
something as seemingly inconsequential as a long walk that one was not
sufficiently physically fit to undertake. They tend to occur more in the spring,
with the peak in April. Severe illnesses and drug treatments are probably the
most significant triggers; in fact, 20% to 86% of patients with gout experienced
a recurrence when they are hospitalized.
Asymptomatic Hyperuricemia
Asymptomatic
hyperuricemia, in which MSU slowly builds up, always precedes gout and is
considered the first stage of the disorder. It can last, however, for an average
of 30 years. Hyperuricemia also does not inevitably lead to gout. In fact, less
than 20% of the hyperuricemic population develops the full-blown arthritic
disease.
Acute Gouty Arthritis
Acute gouty
arthritis is the stage at which the first symptoms of gout appear. Sometimes
gout is heralded by brief twinges of pain (petit attacks) in an affected joint,
which can precede the actual full-blown condition by several years.
MSU crystals begin to form at normal body temperature when concentrations reach
7 mg/dL. They can form at lower concentrations, however, at lower body
temperatures, which occur in areas farther from the heart; this explains why
gout tends to favor joints in fingers and toes first. Symptoms usually begin as
a sudden, severe, and unexpected arthritic attack affecting a single joint in
one of the lower limbs, a condition known as monoarticular gout. The joint of
the big toe is the site of about half of all first gout attacks, a specific
condition called podagra. The site is often medically referred to as the big
toe's metatarsophalangeal (MTP) joint, the point where one of the long five
bones of the foot meets the first digit of a toe.
The joints of the foot, ankle, knee, wrist, elbow, and hand are other frequently
affected sites. In such cases the condition is known as polyarticular gout. More
than one joint is affected in 10% to 20% of first attacks. The pain usually
occurs in joints on one side of the body and it is usually, although not always,
in the lower extremities. People with polyarticular gout are more likely to have
a more gradual onset of pain and a longer delay between attacks. They are also
more likely to experience a low-grade fever, loss of appetite, and a general
feeling of poor health.
The primary symptom, which usually takes eight to 12 hours to develop, is
severe, sometimes crushing pain at and around the joint. In many cases the
attack occurs late at night or early in the morning and announces itself by
waking the sufferer. Some patients describe it as resembling a dislocated bone
and one writer described it as "like walking on my eyeballs." Chills
and mild fever may follow. The area can be so tender that walking and even the
weight of bed sheets can be unbearable. Swelling may extend beyond the joint,
indicating fluid build-up within. The skin over the affected area is often red,
shiny, and tense. After a few days it may start to peel. An untreated attack
will typically peak 24 to 48 hours after the initial appearance of symptoms, and
subside after five to seven days, although it can last only hours to several
weeks.
Intercritical Gout
Intercritical
gout is the term used to describe the periods between attacks. The first attack
is usually followed by a complete remission of symptoms, but in untreated cases
most people can expect a recurrence. One study found that 62% of subjects
experienced at least one further attack within a year. At the end of two years
78% and after 10 years 93% of patients experienced a recurrence of gout.
Symptoms of Chronic Tophaceous Gout
When gout
remains untreated, the intercritical periods typically become shorter and
shorter, and the attacks, although sometimes less intense, can last longer. Gout
may eventually affect several joints, including those that may have been free of
symptoms at the first appearance of the disorder. In rare cases, the shoulders,
hips, or spine are affected. Over the long term, about 10 to 20 years, in
untreated gout the intercritical periods dwindle until gout becomes a chronic
disorder characterized by constant low-grade pain and mild or acute inflammation
in several joints. Persistent gout, moreover, can destroy cartilage and bone,
causing irreversible joint deformities and loss of motion.
Symptoms of Tophi. Tophi, the solid, knobby
MSU crystal deposits that form during this process are generally painless
themselves, but they often cause pain and stiffness in an affected joint and can
erode cartilage and bone, ultimately destroying the joint. Large tophi under the
skin of the hands and feet can give rise to extreme deformities.
How Serious Is Gout?
Left untreated,
gout can develop into a painful and disabling chronic disorder. Tophi are
capable of growing to the size of handballs and can destroy bone and cartilage
in the joints, similar to the process in rheumatoid arthritis. If they lodge in
the spine, they can cause serious damage including compression, although this is
a very rare event. In extreme cases, joint destruction results in complete
disability. But now, after several decades of research into the causes of gout
and the development of drugs for controlling hyperuricemia, gout rarely poses a
long-term threat to health if properly treated. Still, it remains a source of
short-term pain and incapacity for thousands of Americans. Kidney stones occur
in between 10% and 40% of gout patients, and can occur at any time after the
development of hyperuricemia. Although the stones are usually composed of uric
acid, they may also be mixed with other materials. About 25% of patients with
chronic hyperuricemia develop progressive kidney disease, which, in some cases,
ends in kidney failure. Many experts believe, however, that chronic
hyperuricemia is unlikely to be a common cause of kidney disease, and that, in
most cases, the kidney abnormalities come first and cause high concentrations of
uric acid. Gout also accompanies and can be exacerbated by other serious
conditions that are associated with kidney and heart disease including diabetes,
obesity, unhealthy cholesterol levels, insulin resistance, and high blood
pressure. Hyperuricemia has also been associated with a higher risk of death
from heart and circulatory diseases, although it is unknown whether
hyperuricemia is a risk factor independent of the high-risk conditions it often
accompanies.
What Are The Risk Factors For Gout?
Risk factors
are attributes or activities associated with a greater-than-normal likelihood of
developing a particular disorder. Sometimes a causal connection between the
attribute or activity and the disorder can be established, but at other times
there is simply a statistical correlation. The risk factors for gout, of which
there are several, are identical to those for hyperuricemia.
Prevalence
Gout is one of
the most common types of arthritis. In the United States there were an estimated
2.2 million cases of self-reported gout in 1986, and a 1991 publication noted
that Americans lost an estimated 37 million working days a year to gout. It is
estimated that approximately 15 of every 1,000 American males between 35 and 45
years of age have gout and some experts believe that one in 100 men may be at
risk for it. It is very uncommon in less developed countries and in 1952 it was
said to be unknown in China, Japan, the tropics, and rare among African
Americans. The prevalence of gout not only in America but in other developed
countries has, however, been rising in recent decades, possibly because of
dietary and lifestyle changes, greater use of medications that cause
hyperuricemia, and aging populations.
Gender and Age Differences
Among children,
the levels of uric acid in both girls and boys are low, (on average 3 to 4 mg/dL).
Except for rare inherited genetic disorders that cause hyperuricemia, gout in
children is almost unheard of. In males, levels rise substantially at puberty,
with the result that the level exceeds 7 mg/dL (considered to indicate
hyperuricemia) in about 5% to 8% of American men. Gout typically strikes only
after 20 to 40 years of persistent hyperuricemia, so men usually experience
their first attack between the ages of 30 and 50 years old. Men over 40 years
old account for about 90% of the population affected by gout. Less than 5% of
patients with gout are female. The female hormone estrogen appears to facilitate
uric acid excretion by the kidneys, so levels in women remain essentially stable
until menopause, after which they approach male levels. Premenopausal women are
thus much less likely than men of the same age to be hyperuricemic. Women are
more likely to experience gout between the ages of 50 and 70.
Family History
A fairly
substantial proportion of patients with gout (10% to 20%) has a family history
of the arthritic condition.
Other Risk Factors
Obesity.
Researchers report a clear link between body weight and uric acid levels;
obesity may be an especially important risk factor for gout in men. In one
Japanese study, overweight people had between 2 and 3.4 times the incidence of
hyperuricemia as those of normal or low weights.
Hypertension. Hypertension (high blood
pressure) is found in 25% to 50% of patients with gout, but whether it causes
hyperuricemia is uncertain.
Alcohol Use. Alcohol use is associated with
gout and in one study, it was the only notable risk factor for women with gout.
How Is Gout Diagnosed?
Standard
diagnostic tools for gout may include a medical history and physical
examination, a blood test for hyperuricemia, and urine sample. For a definitive
diagnosis of gout, a sample of synovial fluid from the affected joint is
required, which is examined for signs of the characteristic crystals. X-rays can
provide helpful information in some cases.
Ruling Out Other Disorders
As part of the
diagnostic process other disorders that resemble gout symptoms or cause
hyperuricemia should be ruled out. In general, it is easy to distinguish acute
gout that occurs in one joint from other arthritic conditions; the two disorders
that may confuse this diagnosis are pseudogout and septic arthritis, a
potentially life-threatening condition. Chronic gout can often resemble
rheumatoid arthritis.
Pseudogout. Pseudogout is a condition most
likely to be confused with gout. It is caused by deposits of calcium
pyrophosphate dihydrate crystals in and around the joints. Though pseudogout
resembles gout in some ways, the first attack typically strikes the knee rather
than the joint of the big toe, and at least two-thirds of cases affects more
than one joint. The symptoms of pseudogout also appear more slowly than those of
gout, taking days rather than hours to develop. In addition pseudogout is more
likely to occur in the autumn while gout attacks are most common in the spring.
Septic Arthritis. Septic arthritis is a
bacterial infection that can cause inflamed joints, chills, and spiking fever.
The severity of the fever and a high white-blood cell count in the joint fluid
helps differentiate septic arthritis from gout, but at times it is difficult to
tell the conditions apart. A correct diagnosis is critical. It is essential to
administer potent antibiotics to treat septic arthritis.
Rheumatoid Arthritis. Rheumatoid arthritis
can cause distortion in the joints of the fingers, inflammation, and pain that
may mimic gout. A proper diagnosis can be made with a detailed medical history,
laboratory tests, and identification of MSU crystals.
Other Causes of Arthritic Pain. The symptoms
of gout can resemble those of many other disorders, including acute rheumatic
fever, traumatic arthritis, osteoarthritis, serious skin infections, hallux
rigidus (painful stiffness in the first joint of the big toe), and Reiter's
syndrome (a disorder characterized by arthritis, urethritis, and
conjunctivitis). Many of these disorders can be present at the same time as
gout. [ See Box ]
Other Causes of Hyperuricemia. Binge
drinking, fasting, lead toxicity, leukemia, certain uncommon anemias, multiple
myeloma, and lymphomas are also uncommon causes of high uric acid
concentrations.
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OTHER
DISEASES WHICH CAUSE FEVER WITH JOINT AND MUSCLE PAIN
Osteoarthritis.
Infectious Arthritis. Lyme disease, septic arthritis, bacterial
endocarditis, mycobacterial and fungal arthritis, viral arthritis
Postinfectious or Reactive Arthritis. Enteric infection, Reiter's
syndrome, rheumatic fever, inflammatory bowel disease
Rheumatoid Arthritis . (including Still's Disease, also called
Juvenile Rheumatoid Arthritis)
Systemic Rheumatic Illness. Systemic vasculitis, systemic lupus
erythematosus, scleroderma
Fibromyalgia.
Other Diseases . Chronic fatigue syndrome, hepatitis C, familial
Mediterranean fever, cancers, AIDS, leukemia, Whipple's disease,
dermatomyositis, Behcet's disease, Henoch-Schonlein purpura, Kawasaki's
disease, erythema nodosum, erythema multiforme, pyoderma gangrenosum,
pustular psoriasis
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Medical History and Physical Examination
Determining
which joints are affected in a patient suspected of having gout is an obvious
first step in any diagnosis. A physician is more likely to suspect gout as the
cause of an acute attack of arthritis if it first appears in the first joint of
the big toe than if arthritis attacked, for example, a shoulder or hip. The
examiner also needs to determine whether the onset of pain and swelling was
rapid, as symptoms that take days or weeks rather than hours to develop probably
indicate a disorder other than gout. Another possible indicator of gout is
previous damage to an affected joint, because gout often arises in injured
joints.
Blood Test
A blood test is
usually given, although some experts argue that it isn't necessary, given what
is now known about the variability of uric acid levels in people with gout. Uric
acid levels in the blood during an attack of gout do not necessarily mirror
levels before the attack, and in fact can lie within or below the normal range.
Even if hyperuricemia is present, it is very common in the population and does
not necessarily indicate the presence of gout. A low level of uric acid in the
blood however, makes a diagnosis of gout much less probable, and a very high
level increases the likelihood of gout.
24-Hour Urine Sample
It is sometimes
helpful to gauge the amount of uric acid excreted by the patient over the course
of 24 hours, particularly if the patient is young and has pronounced
hyperuricemia that might be related to a metabolic disorder. If the amount
exceeds a particular value, further tests for an enzyme defect or other
identifiable cause of gout arising from uric acid overproduction are justified.
Greater-than-normal amounts of uric acid in the urine also indicate that the
patient faces a greater risk of developing uric acid kidney stones, and can
guide the physician in his or her choice of drug therapy for chronic gout. The
urine is collected during an intercritical period, after the patient has been
placed on a purine-reduced diet. The patient is also asked to temporarily stop
using alcohol and any medications that can interfere with the test. On the first
day of the test, the urine passed by the patient on waking up in the morning is
discarded, but for the next 24 hours the patient collects all of his or her
urine in a special container. The test concludes the next morning with the
patient urinating into the container right after waking up. The container is
then delivered to the patient's physician or sent directly to the laboratory.
Examination of Synovial Fluid
Examination of
synovial fluid is the most accurate method for diagnosing gout; it may even be
helpful in detecting gout during intercritical periods. The synovial fluid is
the lubricating liquid that fills the synovium, the membrane that surrounds a
joint and creates a protective sac. In addition to cushioning joints, this fluid
supplies nutrients and oxygen to cartilage, the slippery tissue that coats the
ends of bones. The procedure for taking a sample of synovial fluid from an
affected joint is called aspiration. A needle attached to a syringe is inserted
into the joint and suction is used to draw the fluid into the syringe. Local
anesthesia is avoided because it can reduce the effectiveness of aspiration, but
normally the procedure is only mildly uncomfortable. Following the procedure
there can be some minor discomfort in the area where the needle was inserted,
but it usually dissipates quickly. Aspiration can cause infection, though this
occurs in less than 0.1% of patients. After the sample is taken, it is sent to a
laboratory, where a microscope is used to look for monosodium urate (MSU)
crystals, which can be detected with polarized light. The laboratory can also
test the sample for infection (always a possibility in cases of gout). Another
benefit of aspiration is that it sometimes eases a patient's symptoms by
reducing swelling and pressure on the tissue surrounding the joint.
X-Rays
For the most
part, x-rays do not reveal any abnormalities during the early stages of gout,
and their usefulness where gout is concerned lies in assessing the progress of
the disorder in its chronic phase and in identifying other health problems whose
symptoms may resemble those of gout. Tophi can be seen on x-rays before they
become apparent on physical examination.
Trial of Colchicine
Until recently
a standard diagnostic test was administering a trial of the traditional antigout
drug colchicine. Improvement in the patient's condition after taking the drug is
an indication of gout. There are limitations, however, to this approach.
Colchicine often has distressing side effects including nausea, vomiting,
diarrhea, and abdominal cramps when taken orally. In any event, its
attractiveness as a diagnostic tool is limited because it can also relieve
symptoms in other arthritic conditions, including pseudogout.
How Is Gout Treated?
General Guidelines
Acute attacks
of gout and long-term treatment of gout and its associated hyperuricemia require
different approaches. All phases are treated mainly with drugs. There are also
specific treatment regimes for conditions associated with gout, including uric
acid nephropathy and uric acid nephrolithiasis.
Treatments for Asymptomatic Hyperuricemia. Because
asymptomatic hyperuricemia usually does not lead to gout or other health
problems, and would have to be treated with drugs that present certain risks and
can be expensive, treatment to prevent a first attack of gout in hyperuricemic
patients is considered inadvisable. In unusual circumstances, for example when
very high uric acid levels threaten the kidney, treatment may be justified.
Treatment of Acute Gouty Arthritis. Drug
treatments for acute attacks of gout are aimed at relieving pain and reducing
inflammation. Powerful forms of nonsteroidal anti-inflammatory drugs (NSAIDs)
are the drugs of choice for an acute attack. Colchicine or corticosteroids may
also be used. Rest, applying cold, and protecting the affected joint with a
splint can also promote recovery. Acute attacks respond best to immediate
treatment. After the first attack, some physicians advise their patients to keep
a supply of medications on hand so that self-medication can begin at the first
sign of symptoms of a second acute attack.
Treatment for Intercritical Period and Tophaceous Gout.
During the period between gout attacks, patients are advised to avoid foods
high in purines and to maintain a healthy weight. Patients should also avoid
alcohol and reduce any stress. Many patients do not require medications. Usually
preventive drug therapy is used only if there are two or three attacks that
occur within a year. Some physicians prescribe low-dose NSAIDs or colchicine to
prevent recurrent attacks. Increasing the dose when a patient believes an attack
is pending can often abort it. These are simply anti-inflammatory drugs,
however, and have no effect on hyperuricemia.
The goals of antihyperuricemic therapy are to reduce uric acid levels to normal,
decrease the frequency of attacks, and to dissolve monosodium urate (MSU)
crystals and tophi. Allopurinol and drugs known as uricosurics, which include
probenecid and sulfinpyrazone, are available for these purposes and are all very
effective. Which drug to prescribe depends on individual conditions. [ See
Specific Drugs for Long-Term Treatment, below.] When and if to prescribe
them at all, however, is not entirely clear. Some physicians do not prescribe
them if hyperuricemia is mild or until a patient has had two attacks. Others
prescribe them immediately after a single attack. It should be noted that any of
these drugs can actually precipitate acute gout symptoms and so should not be
used until symptoms have subsided, and then the patient should start with small
doses that gradually increase. Colchicine or an immediate-acting NSAID, such as
naprosyn, should be given during the initial months of therapy to prevent
symptom attacks. Most of the time, antihyperuricemic therapy means taking a drug
routinely throughout life, which many people find difficult to adhere to. In
rare cases, surgery is used to treat the effects of chronic gout.
Specific Drugs Used for Acute Attacks
Nonsteroidal
Anti-Inflammatory Drugs (NSAIDs ). Nonsteroidal
anti-inflammatory drugs (NSAIDs) block prostaglandins, the substances that
dilate blood vessels and cause inflammation and pain. They are taken orally at
their highest safe dosage as long as symptoms persist and for three or four days
after. There are dozens of NSAIDs. Indomethacin (Indocin) in doses up to 200 mg
a day is the usual choice for gout. The first dose of indomethacin usually
begins to act against the pain and inflammation of gout within 24 hours, and
often much sooner. Ibuprofen, naproxen, sulindac, or others are good
alternatives particularly for elderly patients who might experience confusion or
bizarre sensations with indomethacin [ see below ]. (Aspirin is also an
NSAID, but in low doses is associated with a higher risk for gout and should be
avoided.)
All NSAIDs are capable of damaging the mucous layer and causing ulcers and
gastrointestinal (GI) bleeding. One study indicated that taking NSAIDs for only
six months posed a risk for symptomatic ulcers that was greater than 1%. Regular
use of even over-the-counter NSAIDs may be hazardous for anyone. They also
appear to delay the emptying of the stomach, which may interfere with the
actions of other RA drugs. The elderly, in any case, are at special risk.
Younger nonsmoking adults adapt better to NSAIDs. Bleeding and ulcers can occur
at any time, with or without symptoms. The risk for bleeding is continuous as
long as a patient is on these drugs and may even persist as long as a year after
the drug is discontinued. One study ranked the sixteen most commonly used NSAIDs
according to risk for ulcers and bleeding. Those at lowest risk were nabumetone
(Relafen), etodolac (Lodine), salsalate, and sulindac (Clinoril). At medium risk
were diclofenac (Voltaren), ibuprofen (Motrin, Advil, Nuprin, Rufen), naproxen
(Aleve, Naprosyn, Naprelan, Anaprox), and tolmetin (Tolectin). Drugs within this
group, however, vary in risk. Studies show, for example, that short-term use of
naproxen is twice as likely as ibuprofen to be associated with hospitalization
from GI bleeding. Although ketoprofen (Actron, Orudis KT) was considered a
medium-risk drug, another study reported that even one week of taking the drug
at low doses causes significant GI injury. The highest risk for GI bleeding were
flurbiprofen (Ansaid), piroxicam (Feldene), fenoprofen, indomethacin (Indocin),
meclofenamate (Meclomen), and oxaprozin. Others not compared in this analysis
were diflunisal (Dolobid) and ketorolac (Toradol).
A gel containing ibuprofen can be applied to sore joints and may pose less risk
for gastrointestinal side effects. The drug omeprazole (Prilosec), known as a
proton-pump inhibitor, may both heal and help prevent NSAID-related ulcers.
Misoprostol (Cytotec) is also commonly used to prevent NSAID-induced ulcers; in
one study, a combination of the NSAID diclofenac and misoprostol (Arthrotec)
resulted in 65% to 80% fewer ulcers than in patients who took NSAIDs alone. Side
effects of misoprostol include diarrhea, cramps, and gas. Common antacids, or H2
blockers, such as ranitidine (Zantac), cimetidine (Tagamet), famotidine (Pepcid),
and nizatidine (Axid), reduce symptoms caused by gas but do not keep NSAIDs from
causing ulcers. In fact, such drugs may pose a danger by masking symptoms of
developing ulcers.
Other side effects of NSAIDs include dizziness, ringing in the ear, headache,
and skin rash. Depression has also been noted. Kidney abnormalities have been
reported in people taking NSAIDs, which resolves when the drugs are withdrawn.
NSAIDs may also increase blood pressure, particularly in those on medications to
reduce hypertension. Piroxicam (Feldene), naproxen (Aleve), and indomethacin (Indocin)
appear to pose the greatest risks for high blood pressure. (Sulindac has the
smallest effect.) People with hypertension, severe vascular disease, kidney, or
liver problems, and those taking diuretics must be closely monitored if they
need to take NSAIDs. Any sudden weight gain or swelling should be reported to a
physician. Because NSAIDs reduce the clotting of the blood, anyone undergoing
surgery should stop taking the medication a week before the operation. Diabetics
taking oral hypoglycemics may need to adjust the dosage if they also need to
take NSAIDs because of possible harmful interactions between the drugs. Alcohol
abuse may increase the risks for bleeding.
Colchicine. Colchicine, a derivative of the
autumn crocus (also called the meadow saffron), has been used against gout for
centuries. It is highly effective though no longer the first drug of choice
because of its frequent and unpleasant side effects. The oral regimen requires
doses every hour until the patient either improves or side effects develop;
improvement should be evident by the tenth dose. Although oral colchicine
usually eliminates the pain of an acute attack within 48 hours, it is unsuitable
for many patients because of nausea, vomiting, diarrhea, or abdominal cramps
after taking the drug. Cimetidine (Tagamet) and the antibiotic erythromycin can
intensify the gastrointestinal side effects of colchicine. Overdose can be
fatal. Intravenous administration of colchicine relieves episodes of gout
without gastrointestinal effects and for a time, physicians hoped it could be
used routinely. The intravenous route has some serious side effects, however,
and poses an increased risk for injury to the kidney, liver, central nervous
system, and bone marrow. The drug, in general, is not appropriate for patients
with kidney, liver, or bone marrow disorders. It can also effect fertility.
Corticosteroids. The corticosteroids, known
commonly as steroids, are used only when patients cannot tolerate other
anti-inflammatory drugs or they are ineffective. They include triamcinolone
(administered by injection) and prednisone (taken orally). Corticotropin (ACTH),
a drug that converts to a steroid, is another option. A single intravenous dose
is usually sufficient, and some physicians believe it is the most rapid and
reliable method for terminating an attack. If only one joint is affected, an
injection may be administered directly to the site. Oral doses are usually given
for seven to 10 days to prevent a rebound attack, which can occur after a
corticosteroid injection. Colchicine is sometimes given two or three times daily
along with the steroid and for several days after discontinuing it. These drugs
should only be administered for short periods and not used for long-term
treatment.
COX-2 Inhibitors. Celecoxib (Celebrex) and
rofecoxib (Vioxx) are new drugs known as COX-2 (cyclooxygenase-2) inhibitors,
the so-called super-aspirins. Standard NSAIDs block two prostaglandin-producing
enzymes called cyclooxygenase 1 and 2 (COX-1 and 2). The new drugs block COX-2,
which is responsible for most inflammatory effects, but not COX-1, which
normally protects the stomach. Short-term studies comparing them to a number of
NSAIDs, are indicating that they may be as effective and less harmful to the GI
tract than NSAIDs. It is not yet known if they are safe and effective for gout
or other chronic conditions.
Specific Drugs for Long-Term Treatment
Long-term
treatment of hyperuricemia is recommended for tophi prevention and when the
patient has suffered several acute attacks of gout over a number of years, when
the attacks are unusually severe or affect more than one joint, or when
hyperuricemia is caused by an identifiable inborn metabolic deficiency. A number
of effective agents are available. Before starting one of these drugs, any acute
attack should be completely controlled and the joints should not be inflamed;
some physicians prefer to wait about a month after an attack before starting a
prevention program. Urine tests should be performed to determine if the patient
is an under- or over-excreter of uric acid. The uricosuric drugs probenecid or
sulfinpyrazone enhance uric acid excretion and so are appropriate when gout is
caused by under-excretion of uric acid, which occurs in about 80% of cases.
Normal kidney function is essential for taking these drugs. Allopurinol inhibits
uric acid production and is useful for those who overproduce uric acid, who have
kidney disorders, or who have kidney stones.
Uricosuric Drugs. Probenecid (Benemid,
Parbenem, Probalan) and sulfinpyrazone (Anturane) are uricosurics, which are
drugs that prevent the kidney from reabsorbing uric acid and so increase the
amount excreted in the urine. Uricosuric drugs are usually the choice for
patients under 60 years old who have normal diets and kidney function and have
no risk of kidney stones. Uricosuric drug candidates should also produce no more
than 700 to 800 mg of uric acid in urine over a 24-hour period. These drugs may
actually intensify gout symptoms if they are not started until acute attacks
have stopped. The initial doses should be low and then gradually built up.
Adding low-dose colchicine or an NSAID may help prevent gout attacks. Probenecid
is taken twice to three times a day and sulfinpyrazone begins at twice a day and
increases to three or four times daily. The possible side effects of these two
drugs include skin rashes, gastrointestinal problems, anemia, and kidney stone
formation. Sufficient fluid intake is important to help reduce acidity and so
prevent uric acid kidney stones. To reduce the urine acidity as quickly as
possible, patients may also be given sodium bicarbonate supplemented by
acetazolamide. NSAIDs, particularly aspirin, as well as other salicylate drugs,
interfere with these drugs and reduce effectiveness, so they should be avoided;
patients who require minor pain relief should take acetaminophen (Tylenol and
others). Uricosurics also interact with many other drugs, and a patient should
be sure to inform the physician of any medications they are taking. A uricosuric
combined with allopurinol is occasionally effective in cases where using just
one drug is not. Probenecid combined with colchicine is more effective than
probenecid alone, but patients respond differently to this regimen depending on
the dosage balance, so it needs to be carefully individualized.
Allopurinol. Allopurinol (Lopurin, Zyloprim)
blocks uric acid production and is the drug most often used in long-term
treatment for older patients and those who are over-producers of uric acid
(levels of excreted uric acid are over 800 mg during a 14-hour period). It is
also considered the drug of choice for patients with impaired kidney function, a
history of kidney stones, and for tophaceous gout. Allopurinol is taken orally
only once a day in doses of 100 mg to 600 mg, depending on the patient's
response to treatment. The drug's side effects, experienced by 3% to 5% of
patients, include skin rashes, leukopenia (a reduction in the number of white
blood cells), thrombocytopenia (a reduction in the number of platelets),
diarrhea, headache, and fever. It may also increase the risk for cataracts. When
it is first used, allopurinol can trigger further attacks of gout, and thus
during the first months (or longer) of therapy the patient is also given a NSAID
or colchicine to forestall that possibility. Some patients experience an
allergic reaction to allopurinol, which can be fatal in rare cases. Such
individuals may be able to build up their tolerance for the drug by undergoing a
desensitization process. Even if a first attempt at desensitization fails, one
case study suggested that subsequent attempts may still be successful.
Colchicine and NSAIDs. Low doses of NSAIDs
or colchicine are used to prevent gout attacks in patients who are starting
anti-hyperuricemic therapies. For patients who cannot take either allopurinol or
a uricosuric, low daily doses of oral colchicine provide a possible alternative
treatment for hyperuricemia, although not among patients with kidney or liver
disease.
Surgery
Surgery is
sometimes used to remove large tophi that are draining, infected, or interfering
with the movement of joints. Several other surgical procedures are available for
relieving pain in and improving the function of affected joints. It is sometimes
necessary to replace joints.
Treatment for Pseudogout
There is no
cure for pseudogout, but there are treatments to relieve the pain and
inflammation and reduce the frequency of attacks. NSAIDs are effective for
treating inflammation and pain from pseudogout. For acute attacks in large
joints, fluid aspiration alone or with steroids may help. Intravenous colchicine
is also helpful but may be toxic. Pseudogout is a progressive disorder that can
destroy joints, and joint replacement may be required.
Treatment of Kidney Disorders Related to Gout
Uric
Acid Nephropathy. Uric acid nephropathy is common in chemotherapy
patients. In such cases it is preventable if they are adequately hydrated and
given allopurinol before chemotherapy begins. Treatment has reduced the death
rate in cases of uric acid nephropathy from about 50% to close to zero.
Uric Acid Nephrolithiasis. Uric acid stones
are dissolved by giving the patient allopurinol to reduce the concentration of
uric acid in his or her urine. The patient also takes oral sodium bicarbonate or
acetazolamide (Diamox) to alkalinize the urine. Drinking at least 10 to 12
eight-ounce glasses of water and other nonalcoholic beverages every day is
important as well. [For more information see Kidney Stones. ]
What Lifestyle Measures Can Help Prevent Gout?
Avoiding Excessive Energy Demands
Any activities
that increase energy demands also increase metabolism or purines that produce
uric acid. Avoiding stress and staying healthy are important for preventing
attacks.
Dietary Recomendations
Avoid
Foods Containing Purines. Because uric acid levels are only minimally
affected by diet, dietary therapy does not play a large role in the prevention
of gout. Still, people who have suffered an attack of gout may benefit from
reducing their intake of purine-rich foods if they habitually eat unusually
large quantities of such foods. They include beer and other alcoholic beverages,
anchovies, sardines (in oil), fish roes, herring, yeast, organ meats (eg, liver,
kidneys, sweetbreads), legumes (eg, dried beans, peas, and soybeans), meat
extracts, consommé, gravies, mushrooms, spinach, asparagus, and cauliflower.
Any meat, fish, or poultry has moderate amounts of purines.
Protein Restriction. Diets high in protein,
particularly animal protein, increase uric acid. Although few studies have been
conducted and none have determined the value of reducing protein, one study of
gout patients suggested that eating tofu, which is made from soy and is a source
of complete protein, may be a better choice than meats.
Possibly Helpful Foods and Supplements. Dark
berries and cherries may contain chemicals that lower uric acid and reduce
inflammation. Vitamin C and folic acid supplements may also have some benefits.
(Vitamin A may increase the risk for gout attacks.)
Maintain Healthy Weight
A supervised
weight-loss program may be a very effective way to reduce uric acid levels if
the patient is overweight. Crash dieting, on the other hand, is
counterproductive because it can increase uric acid levels and can cause an
acute attack.
Maintain Fluids
Drinking plenty
of water and other nonalcoholic beverages helps remove MSU crystals from the
body. Some researchers are studying the anti-inflammatory properties of green
tea, which might have some benefit for gout. It should be noted, a Japanese
study reported a higher association between gout and tea drinking (although the
study did not describe the type of tea).
Avoid Alcohol
Alcohol should
be avoided, since it promotes purine metabolism and uric acid production; it
also may reduce excretion of uric acid. Heavy drinking, especially binge
drinking of beer or distilled spirits, should especially be avoided.
Avoid Joint Injury
People with
gout should also attempt to identify and avoid activities that cause repetitive
joint trauma, such as wearing tight shoes.
Prevention during Travel
Travel is an
example of an activity that increases the risk for gout; it not only places
increased demands on the patient, but eating and drinking patterns may change.
Before traveling, patients should discuss preventive measures with their
physicians. The doctor may prescribe a prednisone tablet to be taken immediately
at the first sign of a gout attack; in most cases this stops the episode.
Where Else Can Help Be Obtained For Gout?
The Arthritis Foundation, 1330 Peachtree St., Atlanta GA 30309.
Call(800-283-7800) or on the Internet (http://www.arthritis.org/
)
This is an excellent source for many types of services. The foundation funds
research and provide brochures, video tapes, exercise programs, physician
referrals, and local chapters.
The National Institute of Arthritis and Musculoskeletal and Skin Diseases (NIAMS),
One AMS Circle, Bethesda MD 20892-3675. Call (301-495-4484) or on the Internet (http://www.nih.gov/niams/
)
American Academy of Orthopedic Surgeons, PO Box 2058, Des Plaines, IL 60017.
This organization will send information on arthritis by sending a self-addressed
stamped business envelope. Be sure to designate "Arthritis" on the
outside envelope.
Aids for Arthritis, Inc., (Call 609-654-6918).
Enrichments. Call (800-323-5547) or on the Internet (www.sammonspreston.com
)
Both companies offer supportive devices and products for people with arthritis.
Call for catalogs.
The above information from MD
Consult,
with permission.