Gout

What is Gout?

Gout, often referred to as the “disease of kings and king of diseases,” is one of the most common causes of long-term joint inflammation in the United States. This condition is the result of too much monosodium urate, a type of salt, accumulating in our tissues. Gout was first spotted by Hippocrates in ancient Greece and is now the most well-understood and manageable of all joint diseases.

Gout happens when excess urate salt builds up in body fluids outside of cells, leading to high levels of urate in the blood, or hyperuricemia. This typically occurs when there is more than 6.8 mg of urate per deciliter of blood, which is roughly 400 micromoles per liter. This is the maximum amount of urate that can be dissolved in blood.

Some of the effects of gout may include:

• Sudden and repeated inflammation of the joints, known as an acute gout flare.
• Long-term joint disease, known as chronic gouty arthropathy.
• The buildup of urate in the form of hard nodules, referred to as tophaceous deposits.
• Uric acid kidney stones.
• Long-term kidney disease.

What Causes Gout?

Gout is often caused by a combination of factors, such as genetic predisposition, other health conditions, and diet. In some rare cases, a single genetic defect may lead to gout, usually alongside other health problems. Regardless of the cause, the end result is high levels of uric acid in the blood, which can lead to gout in certain people.

Numerous genes are associated with gout, with some involved in the production of uric acid, and others involved in its re-absorption or excretion in the kidney. Some isolated genetic defects may also be present. About 73% of gout cases are heritable, and roughly half of all gout patients have a family history of the condition.

All humans, along with a handful of other species, lack an enzyme called uricase, which converts uric acid into a more soluble molecule. One side effect of this lack of uricase is a condition known as hyperuricemia, which is characterized by high levels of uric acid in the blood. Humans are the only known mammals that can develop gout naturally. Hyperuricemia can lead to gout, a condition involving the accumulation of uric acid crystals in joints, causing inflammation and pain.

Not everyone with high uric acid levels develop gout. Some other risk factors contribute to the onset, and these include age, sex, obesity, diet, alcohol consumption, use of certain medications, other diseases, and genetic predisposition.

Research has shown that certain lifestyle changes, including increased protein consumption and lack of physical activity, have led to a rise in gout cases. These changes highlight the complex relationship between modern lifestyle habits and the prevalence of gout.

Increasingly, diet is seen as an important factor in managing uric acid levels. Foods and drinks considered high risk for gout and hyperuricemia include seafood, organ meats, red meat, alcohol, sweetened drinks, and soda. Moreover, stress, recent surgery or trauma, and the use of certain drugs can trigger gout flare-ups.

On the bright side, certain dietary changes have been shown to lower uric acid levels and reduce the risk of gout. These include reducing intake of meat and seafood, increasing dairy consumption, following the DASH diet, ensuring adequate intake of vitamin C, and incorporating cherries into the diet.

Risk Factors and Frequency for Gout

Diagnosing gout depends on the specific criteria used. The usual diagnostic methods involve finding a particular kind of crystal in the joint fluid or spotting a certain kind of tissue build-up. Yet, because these methods can be impractical, other criteria have been used such as self-reporting, various medically-approved standards and more recently, the 2015 ACR/EULAR standards which are taken to be 92% effective.

Gender and life stage can play a role in the prevalence of gout. Men usually see more of the urate responsible for gout during puberty and that amount can increase with age. On the other hand, women usually have less urate in their systems but this changes after menopause when their levels can match those of men. This difference in urate levels likely influences the gender-based difference in the risk of getting gout.

The risk of getting gout can also change depending on your age, sex, and country. It’s generally found in 1% to 4% of the population, with a higher risk in men compared to women and an increase in risk as people get older. This is especially true in Western countries where the rate is usually 3% to 6% in men, 1% to 2% in women, with gout becoming more common as one gets older but stabilizing after age 70. In the United States, about 3.9% of adults were diagnosed with gout from 2007 to 2008, with the estimate ranging between 3 to 8 million people. Also, African-Americans were found to be more at risk than White-Americans, particularly African-American women, who are at a significantly higher risk in comparison to their White counterparts.

• In the USA, about 8.7% of people over 70 have gout.
• In Australia, about 7.9% of people over 70 have gout.
• In Sweden, about 7.4% of people over 70 have gout.
• In South Korea, about 1.9% of people over 70 have gout.

The cases of gout have been increasing over the years, particularly in older men. A study showed that this trend, which includes an increase of other related health conditions, has been observed in over 20 years. Likewise, in the UK, the prevalence of gout rose from 1.52% to 2.49% from 1997 to 2012.

Gout patients are also often seen to have other diseases or health conditions such as obesity, hypertension, kidney disease, diabetes, and hyperlipidemia. For example, a study observed that the prevalence of obesity, hypertension, and kidney disease was higher in gout patients compared to the general population. The risk of gout also increases with weight gain.

Diseases associated with gout include hypothyroidism, anemia, psoriasis, lung disease, osteoarthritis, and depression. It’s also associated with an increased risk for certain heart conditions and stroke. Moreover, gout is linked with an increased overall death rate, including specifically from heart disease, infection, and cancer.

The relationship between gout and dementia, including Parkinson’s disease, is still being studied. Some studies suggest a lower risk of dementia in people with gout, while others suggest an increased risk. The link between gout and the risk of developing Parkinson’s disease remains unclear, with studies showing different results.

Signs and Symptoms of Gout

• Asymptomatic hyperuricemia
• Acute gout attacks
• Intercritical period
• Chronic tophaceous gout

During the Asymptomatic Hyperuricemia stage, individuals have high uric acid levels in their blood but do not express any symptoms. Not all patients at this stage will develop gout. If an acute gout episode occurs, this stage ends.

The Acute Gout Attack stage is characterized by sudden, intense joint pain and swelling, often affecting only one joint. Most frequently, these attacks are in the lower extremities, with a particular focus on the first joint of the big toe. Sometimes, gout can affect multiple joints, which could lead to misdiagnosis. Joint pain usually resolves without intervention within 3 to 14 days, but as time goes on, these bouts can occur more often, become less severe, and implicate more joints.

• Sudden, extreme joint pain
• Swelling
• Pain peaking at 24 hours
• Occurrence often at night or early morning
• Additional symptoms may include fever, malaise, and fatigue

Being under stress, such as from a surgery, illness, or drastic dietary change, can trigger gout attacks. When a doctor examines a patient during a flare-up, they typically find the affected joint to be red, swollen, warm, and sensitive to touch.

Following an acute gout attack, patients enter an “Intercritical Gout” phase, where they do not experience any symptoms. However, despite the absence of visible signs, uric acid continues to build up and crystals continue to form in the joints.

The final stage is known as Chronic Tophaceous Gout. Persistent, untreated gout eventually causes this stage, where chalk-like nodules, known as tophi, form under the skin. These nodules are deposits of uric acid and might or might not drain. They are most commonly found around finger and toe joints, knees, and elbows. Overtime, tophaceous gout can cause extensive joint and bone damage, and cause severe deformities.

• Formation of chalk-like nodules
• Joint damage
• Bone destruction
• Severe deformities

It’s worth noting that the impacts of gout can be systemic, affecting not just joints but other parts of the body as well. Cases have been documented where uric acid crystals have been found in the cornea of the eye and even heart valves.

Testing for Gout

Identifying monosodium urate crystals in joint fluid is the primary way to diagnose gout. Doctors usually collect this fluid during a gout flare-up and examine it under specialized light microscopy. The fluid tends to look yellow and cloudy, filled with crystals and white blood cells, particularly neutrophils, which are a type of immune cell.

In septic arthritis, another joint condition, the joint fluid appears more yellow-green and also contains many white blood cells. However, it can be hard to tell the difference between gout and septic arthritis based on the number of white blood cells and neutrophils alone. The real difference can be detected by examining the fluid under a microscope, as well as by its glucose levels. It’s vital to remember that even if crystals are found in the fluid, this doesn’t automatically rule out septic arthritis, as both conditions can happen simultaneously.

A needle-shaped crystal structure under a microscope is a typical sign of gout. This test can confirm a gout diagnosis and help differentiate it from septic arthritis, Lyme disease, or pseudogout, which is caused by a different type of crystal.

Typically, during a gout attack, blood tests may show higher levels of white blood cells, erythrocyte sedimentation rate (a marker of inflammation), and C-reactive protein (another marker of inflammation). However, these are not specific to gout and cannot confirm the diagnosis or distinguish it from septic arthritis.

Around half of the patients experiencing a gout attack may not have elevated levels of uric acid in their blood. Measuring uric acid during an attack doesn’t help in the diagnosis of gout. High uric acid can hint towards gout, but it doesn’t confirm the diagnosis alone, as it can also be found in people without symptoms. The best time to measure uric acid levels in the blood is at least two weeks after a gout flare.

The amount of uric acid in urine can also be measured, especially in younger patients with undetermined reasons for high uric acid. This test helps distinguish whether the body is producing too much uric acid or isn’t getting rid of it efficiently, which can guide treatment.

While it’s not commonplace, ultrasound and dual-energy CT scans can be used to detect gout. On ultrasound, gout appears as an enhanced ring around the cartilage, also known as the double contour sign. Dual-energy CT scans can identify uric acid deposits by measuring their reaction to different X-ray lights. Both methods can aid in diagnosing gout with a fair amount of specificity and accuracy.

Treatment Options for Gout

Medical treatment of gout may include nonsteroidal anti-inflamatory drugs , colchine,and corticosteroids. Dietary modifications and maintaining a healthy weight.

What else can Gout be?

When dealing with a sudden attack of gout, the following conditions need to be ruled out by the doctor, as they can cause similar symptoms:

• Calcium pyrophosphate crystal deposition disease
• Basic calcium phosphate crystal disease
• Septic arthritis (a joint infection, which can also occur along with crystal arthritis)
• Osteoarthritis (OA)
• Psoriatic arthritis
• Cellulitis (a skin infection)
• Physical injury

For chronic gout, where hard lumps (called tophi) develop, the doctor may also consider these conditions as potential causes:

• Dactylitis (inflammation of a finger or toe)
• Rheumatoid arthritis
• Osteomyelitis (a bone infection)

What to expect with Gout

How gout affects a person can vary depending on their other health conditions. People with heart-related health problems typically have a higher risk of death. However, with the right treatment, most people living with gout can lead a normal life with minor follow-up health issues.

Individuals who start showing gout symptoms early in life usually have a more severe form of the disease. If they don’t make changes to their lifestyle, they’re likely to experience recurring bouts of gout.

Possible Complications When Diagnosed with Gout

Gout can lead to a variety of health concerns affecting different parts of the body:

Skeleton-related Complications:

• Tophi, which are deposits of uric acid crystals
• Deformation of the joints
• OA or Osteoarthritis, the wearing away of joint cartilage
• Loss of bone mass or Bone loss

Urinary System-related Complications:

• Urate nephropathy, when uric acid damages the kidneys
• Nephrolithiasis, another term for kidney stones

Eye-related Complications:

• Conjunctivitis, also known as pink eye
• Uveitis, inflammation that affects the middle part of the eye
• Scleritis, severe inflammation of the white outer coating of the eye

Preventing Gout

It’s important for patients to make changes to their lifestyle to help reduce the risk of experiencing bouts of gout and slow down the advancement of the condition. Here are some key things patients should know:

Making lifestyle changes is highly recommended for patients with gout. This can be things like losing weight, drinking less alcohol, and avoiding certain foods. While these changes can make a big difference and support medication treatments, they may not always be enough to completely control or reverse gout.

Gaining weight or carrying excess fat are both things that can increase someone’s risk of developing gout. For those who already have gout and are overweight, losing weight is probably a good idea. Losing weight can help lower the amount of uric acid in the blood (urate) and relieve gout symptoms.

The best kinds of diets for managing gout are ones which include a good amount of protein from plants and low-fat dairies. At the same time, patients should try to eat less food from animal sources that are high in purine like shellfish and red meat. Cutting back on fatty food and substituting simple sugars for complex carbohydrates (like whole grains) is also a good idea.

It’s recommended to either avoid or drastically cut back on sugar-laden juices, alcohol, and beverages that are high in high-fructose corn syrup.