What is Gout?
Gout is a common type of inflammatory joint disease characterized by the formation of uric acid crystals in the joints. Patients usually develop exquisite joint pain, swelling, and warmth – this most often occurs in the big toe.
Gout typically affects people with obesity and diabetes, but may also occur in individuals with cancer and blood cell disorders.
The condition is not life threatening but can lead to significant pain and disability if it is not recognized or treated early. Since gout is common and can affect quality of life, it is important to become educated about its causes, diagnosis, and treatment. By the end of this article, you will be able to answer the following important questions:
- What causes Gout?
- How common is Gout?
- What are the symptoms and signs of Gout?
- How is Gout diagnosed?
- How is Gout treated?
What causes Gout?
Gout is caused by the formation of uric acid crystals in the joint space, which promotes inflammation – warmth, redness, and pain. The most common form of gout is podagra, which is characterized by severe pain and inflammation of the big toe.
Gout can be caused by either the overproduction or under secretion of uric acid. This may be related to genetic and environmental factors. Common risk factors include:
- Family history of gout
- Cell or tissue breakdown – which may occur with cancer (e.g. leukemia) or blood cell disorders (e.g. hemolytic anemia)
- Kidney disease
- Medications – diuretics such as Hydrodiuril (hydrochlorothiazide) or Lasix (furosemide)
Diet is also a major contributor to the development of gout - foods commonly associated with this condition include:
- Red meat
- Soda containing sugar
- High-fructose corn syrup
Uric acid is a substance located inside our cells, people with cell and tissue breakdown have increasing levels of uric acid in circulation, thus, when uric acid enters the joint, it causes an inflammatory reaction leading to pain and swelling.
Our kidneys are responsible for eliminating uric acid from our bodies. When people have impaired kidney function, their kidneys have trouble getting rid of the uric acid. Eventually, uric acid finds itself in joint tissues and leads to inflammation and pain.
How common is Gout?
Gout is an exceedingly common inflammatory joint condition that affects approximately 4% of Americans. This is likely related to the obesity and diabetes epidemic in the United States.
The disease most commonly affects men between puberty and middle age. However, post-menopausal women also have a relatively high incidence of gout - studies indicate that hormones such as estrogen protect against gout development.
What are the symptoms and signs of Gout?
The most common symptoms of gout include:
- Joint pain and inflammation – this typically involves the big toe, but can also affect the knee or other small joints
- Joint swelling & warmth
- Redness of the joint
- Decreased joint mobility
Pain can be severe and debilitating. Very minor stimuli such as gentle contact with the inflamed joint can be excruciating – people may have trouble putting on socks or shoes.
Patients with high uric acid levels that do not receive treatment may develop tophaceous gout, which is characterized by the deposit of firm crystals in the elbows, tendons, and bursa.
How is Gout diagnosed?
The diagnosis of gout is suggested based on the patient’s symptoms and signs. However, the symptoms of gout can overlap with joint infection and other crystal-induced joint inflammation. All of these conditions can cause redness, warmth, swelling, and reduced mobility of the joint – they may also cause constitutional symptoms such as malaise and fever. High fever and severely reduced joint mobility is more suggestive of infection.
The definitive diagnosis of gout requires a procedure called arthrocentesis. During this procedure, your doctor will thoroughly clean the skin using an antiseptic solution such as Betadine (povidone-iodine) or ChloraPrep (chlorhexidine). They may spray a medication called ethyl chloride over the joint to numb the region.
After the joint is prepped, they will then enter the joint space using a needle and syringe. The syringe will be drawn to remove synovial (joint space) fluid - turbid or cloudy fluid is suggestive of gout. If frank pus is expressed from the joint space – infection is more likely. Your doctor will typically analyze the joint fluid for inflammatory cells, bacteria, and crystals. They also usually send the sample for a bacterial culture.
Crystal analysis involves checking the joint fluid under the microscope with polarized light – this helps determine the type of crystals. Uric acid crystals are typically needle-shaped. People with a condition called calcium pyrophosphate disease can also have joint inflammation and crystals on joint fluid analysis – but these crystals are usually rhomboid shaped – a key distinguishing feature between the two conditions.
Besides the aforementioned tests, your doctor will also likely obtain blood tests such as a comprehensive metabolic panel, complete blood count, inflammatory markers (ESR, CRP), and serum uric acid level. If your serum uric acid is elevated, they may also obtain a 24-hour urine collection and assess the urine for uric acid levels – this helps determine whether or not your kidneys are adequately getting rid of uric acid from the body. If the diagnosis of gout is not clear, your doctor may order blood tests to rule out rheumatoid arthritis, such as rheumatoid factor (RF) and anti-CCP.
Sometimes, you doctor will also recommend getting x-rays of the involved joints.
How is Gout treated?
The treatment of gout is multifaceted. Most people are encouraged to lose weight and reduce the amount of alcohol, red meat, and processed sugars they consume such as soda.
Acute gout flares typically require the use of non-steroidal anti-inflammatory drugs (NSAIDs) such as:
Occasionally, your doctor may recommend Colcrys (colchicine). If you cannot take NSAIDs or Colcrys, you may benefit from a short course of oral corticosteroids such as prednisone or Medrol (Solumedrol). Symptoms are usually very responsive to treatment and self-limited – meaning that they can resolve on their own within a couple of weeks.
The long-term treatment of gout typically involves a class of medications called xanthine oxidase inhibitors – these medications reduce the production of uric acid. The most commonly prescribed drugs in this class include:
Your doctor may also recommend Probenecid – a medication that increases uric acid excretion by the kidneys.
Gout Patient Summary:
- Gout is a common inflammatory joint condition caused by uric acid crystal deposit in the joints
- It most commonly affects middle-aged men with risk factors such as obesity, diabetes mellitus, and kidney disease – it may also occur in people with certain types of cancer or blood disorders
- The most common symptoms include pain, swelling, warmth, and decreased mobility in the joint - Patients can also develop malaise and low-grade fever.
- Gout is diagnosed by obtaining a fluid sample from the joint (arthrocentesis) and evaluating for the presence of uric acid crystals
- Treatment of gout flare usually includes the use of NSAIDs (eg, Indocin, Advil), Colcrys (colchicine), or Prednisone.
- Patients may require long-term treatment with Zyloprim (allopurinol) or Uloric (febuxostat). Sometimes your doctor will recommend probenecid.
- Hainer BL, Matheson E, Wilkes RT. Diagnosis, treatment, and prevention of gout. Am Fam Physician. 2014 Dec 15;90(12):831-6.
- Neogi T. Clinical practice. Gout. N Engl J Med. 2011 Feb 3;364(5):443-52.
The above information is an educational aid only. It is not intended as medical advice for individual conditions or treatments. Talk to your doctor, nurse or pharmacist before following any medical regimen to see if it is safe and effective for you.