Gout

Edited by Daniel Guss, MD, MBA 

 

Summary

Gout is a painful arthritic condition that can affect any joint or even soft tissues such as tendons, but commonly involves the joint at the base of the great toe (see Figure 1). Gout occurs when uric acid (normally present in the blood) crystallizes in the lining of the involved joint. These uric acid crystals cause an intense inflammatory reaction that often creates marked pain and swelling. Risk factors for gout include elevated blood uric acid levels, potentiated by a diet high in red meat, seafood, or alcohol. Initial treatment is aimed at decreasing symptoms and may include the use of medications designed to decrease inflammation, rest, and ice. Long-term management is oriented towards preventing recurrent attacks and limiting the long-term effects that gout may have on the involved joint.

Figure 1: “The Gout” by James Gilray 1799

Clinical Presentation

Gout describes a medical condition in which crystals deposit themselves in various tissues in the human body. These crystals are made of a substance called uric acid, a substance normally found in human metabolism as we break down the various chemicals that make up DNA. Uric acid is normally dissolved in our blood and excreted in our urine, but when its concentration gets too high or in patients prone to gout, it can crystallize out of the blood and deposit into joints, tendons, or other issues.

Patients often report a relatively sudden onset of severe symptoms including pain, swelling, and redness. Gout may involve almost any joint in the body, but in about 75% of first attacks, it affects the joint at the base of the big toe (Podagra). Less commonly it can also affect the ankle. We know that certain individuals are more susceptible to attacks of gout:

• Elevated blood uric acid levels. Approximately 10-20% of people with high blood uric acid levels will eventually have a gout attack
• A prior history of gout is perhaps the biggest risk factor for future attacks
• Intake of foods high in protein (increased intake of purines, a component of DNA). These foods include: red meat, fatty fish (tuna, salmon, mackerel, herring, and sardines), and seafood (shrimps, prawns, scallops, and lobster)
• Alcohol intake may precipitate a gout attack
• Kidney problems may increase the risk of an attack of gout because about 70% of the uric acid in the blood is eventually excreted through the kidneys. If the kidneys are not working optimally, the uric acid level in the blood will tend to rise
• Obesity
• Diabetes (elevated blood sugar)

Not all patients with gout have a high uric acid, though many do, and therefore the diagnosis of gout is often based on a patient’s symptoms. The diagnosis of gout is confirmed by removing fluid from the affected joint (“tapping” or “aspirating” the joint) and looking at it under the microscope. Elongated rods of uric acid crystals will be seen when viewed under the microscope with polarized light.

Imaging Studies

X-rays are likely to be normal, except after multiple attacks or if there are other problems in the joint, such as hallux rigidus (arthritis) in the great toe. In patients who have suffered from gout over a long period of time, crystal collections (called “tophi”) may reach a size where they can be seen on x-rays or may show bone erosions around the joint characteristic of gout. X-rays can be helpful to rule out other conditions that may cause similar symptoms, such as fractures, severe osteoarthritis, Charcot arthropathy, infection, or pseudogout (another type of crystal that can also deposit in joints). MRI is usually not indicated in making the diagnosis of gout.

Treatment

The initial treatment of a gout attack is aimed at reducing the pain, which can be quite severe. After the initial symptoms have been resolved, long-term management of gout focuses on minimizing the risk of future attacks of gout.

Initial Treatment

• Anti-inflammatory medications (NSAIDs): NSAIDs are the primary treatment of an acute attack of gout. NSAIDs help blunt the intense inflammatory response the uric acid crystals created in the joint lining. Anti-inflammatory medications can start decreasing symptoms within a few hours. Patients may experience stomach discomfort and, in many instances, anti-inflammatory medications should be combined with a medication that helps “protect” the stomach. In patients that have had serious stomach problems, such as ulcers or bleeding, NSAIDs should not be given and another treatment option should be considered.
• Oral corticosteroid medications: Oral steroids, such as prednisone, can also help decrease the inflammation in the involved joint. These can be quite effective, but have potential side effects that should be discussed with your treating provider.
• Colchicine: This medication can be effective if taken within 12 hours of the attack. Some people develop diarrhea or nausea as a side effect.
• Steroid injection in the joint: Injecting steroids directly in the joint may have some benefit. In addition, removing fluid at the time of the injection may allow the diagnosis of gout to be confirmed. While frequently used to diminish symptoms in other forms of arthritis, the evidence to support injecting steroids into a joint during a gout attack is limited.
• Ice: Ice applied to the joint for 10-15 minutes at a time may help improve the acute pain associated with a gout attack. It is unclear if applying heat to the involved area is a good idea. Applying heat will increase the blood flow to the area and may aggravate symptoms. It has been suggested, however, that increasing the temperature to the area may decrease the formation of crystals in the joint.
• Elevating the involved joint: Elevating the involved extremity (ex. propping your foot up on a pillow) may help symptoms by decreasing the swelling.
• Drinking lots of water: It is thought that drinking lots of fluid will help dilute the uric acid crystals and thereby decrease the chance of more crystals forming in the joint. In addition, increase fluid intake may encourage the excretion of uric acid in the urine.

Long-Term Management of Gout

A variety of treatment approaches have been recommended to minimize the risk of recurrent gout attacks including:

• Allopurinol: This medication decreases uric acid level in the bloodstream (by inhibiting an enzyme that produces uric acid called xanthine oxidase). It is commonly used and generally safe. It should NEVER be taken with Azathiorine (Imuran), however, because a potentially fatal reaction can occur.
• Low Fat, Low Protein Diet: Purines are commonly found in beef and seafood, whose breakdown leads to uric acid. Therefore, decreasing the intake of these foods will tend to decrease uric acid levels in the blood and lessen the risk of future gout attacks.
• Avoid Alcohol: Alcohol consumption can precipitate gout attacks and should be minimized in those prone to gout.
• Avoid high sugar soft-drinks: Many soft-drinks that contain high fructose syrup can increase blood uric acid levels, thereby making gout flares more likely.
• Surgical Resection of Gouty Tophi: Occasionally, the collection of uric acid will form lumps (gouty tophi) in the lining of the involved joints. In rare instances, these lumps can become large enough that they will need to be removed surgically.

 

Edited on March 7, 2017

Previously Edited by Michael Salamon, MD

mf/ 7.3.18