Gout – Diagnosis, Symptoms, and Treatment

What is Gout?

Gout is an inflammatory disease of the joints that result from crystals of Uric acid forming within them.  Patients usually develop recurrent episodes of 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, blood cell disorders, and a genetic predisposition for the disease.

Gout 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.

What Causes Gout?

Gout is caused by the formation of uric acid crystals in the joint space. These crystals promote inflammation leading the immune system to attack the joint and the crystals within it.  The most common form of gout is podagra, which is characterized by severe pain and inflammation of the big toe.

The uric acid crystals that lead to gout are caused by either the overproduction or reduced elimination of uric acid.  This is most often related to multiple genetic and environmental factors. There are several medical conditions can also play a major role.  Common risk factors include:

• Family history of gout
• Cell or tissue breakdown – which may occur in cancer (e.g. leukemia) or blood cell disorders (e.g. hemolytic anemia)
• Obesity
• Diabetes
• 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
• Seafood
• Alcohol
• Soda containing sugar
• High-fructose corn syrup

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. 

Even in patients with normal kidney function uric acid can accumulate. This substance is a major component of all cells, the breakdown of cells can also lead to massive amounts of uric acid accumulation and the development of gout. This is how conditions such as cancer, leukemia, and the breakdown of blood cells can lead to gout. 

How Common is Gout?

Gout is a relatively common condition and is thought to affect around 4% of the US population, around 8.3 million individuals. It is far more common in individuals with other healthcare conditions such as diabetes and obesity. Gout is most common in men between puberty and middle age. In women gout is more common in those who are passed the age of puberty as estrogen protects against the development of gout. 

Signs and Symptoms

Gout generally begins with mild discomfort and pain in one of the joints, most commonly a joint within the large toe. These symptoms rapidly progress to severe pain, swelling, and warmth in the joint. These symptoms are often significant enough to limit mobility. In summary the most common symptoms are:

• 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

The pain with gout 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 and preforming basic daily tasks around the house or at work.

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. These “topha” do not result in the same levels of pain as classic gout but can limit rage of motion in the affected joints.

Diagnosis

The diagnosis of gout is often suspected based on the signs and symptoms alone.  However, the symptoms of gout can overlap with joint infection and other crystal-induced joint inflammation syndromes. All of these conditions can cause redness, warmth, swelling, and reduced mobility of the joint – they may also cause other symptoms such as malaise and fever.  High fever and severely reduced joint mobility is more suggestive of infection which requires treatment with antibiotics.

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.  A small amount of synovial (joint space) fluid will be removed - 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 (CMP), complete blood count (CBC), 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, your doctor will also recommend getting x-rays of the involved joints to rule out fractures and other injuries that can lead to joint pain and inflammation.

Gout Medication and Treatment

Gout treatment is focused around prevention. Losing weight and reducing the intake of alcohol, red meat, and processed sugar can dramatically reduce the risk of gout flares. 

The prevention of gout can be enhanced by medications, this most commonly 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:

• Zyloprim (allopurinol)
• Uloric (febuxostat)

Your doctor may also recommend Probenecid – a medication that increases uric acid excretion by the kidneys.

Even with prevention it is possible for symptoms of gout to appear. This is known as a gout flare and is typically managed with non-steroidal anti-inflammatory drugs (NSAIDs) such as:

• Indocin (indomethacin)
• Advil (ibuprofen)
• Naprosyn (naproxen)
• Celebrex (celecoxib)

Occasionally, your doctor may recommend Colcrys (colchicine) which works to reduce the inflammation that results from uric acid crystals. This medication has significant side effects and is generally used only in more severe cases. 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.

 

References:

1. Hainer BL, Matheson E, Wilkes RT. Diagnosis, treatment, and prevention of gout. Am Fam Physician. 2014 Dec 15;90(12):831-6. - https://www.ncbi.nlm.nih.gov/pubmed/25591183
2. Neogi T. Clinical practice. Gout. N Engl J Med. 2011 Feb 3;364(5):443-52. - https://www.ncbi.nlm.nih.gov/pubmed/21288096