Patients present with one or more erythematous, swollen and painful joints with restricted movement. The big toe is frequently involved (podagra). Other commonly involved joints include the instep, ankle, knee and wrist joints. The attacks are sudden and typically last up to 8 to12 hours. Systemic involvement is rare and may be indicated by the presence of fever.
A detailed history and physical examination is often sufficient to form a diagnosis.
The imaging techniques that currently have a role in the imaging of gout include conventional radiography, ultrasound, computed tomography, dual energy computed tomography, magnetic resonance imaging and nuclear medicine .
Axial gouty arthropathy should be included in the differential diagnosis of chronic low back pain, mainly when several risk factors for gout are present . The presence of tophi is diagnostic. In other cases, a diagnosis can be based on physical examination and confirmed by lab tests.
Gout, whilst in principle considered to be well understood and simple to treat, often presents diagnostic and management challenges, with evidence to suggest that it is often inadequately treated and poor compliance is a major issue .
Treatment of gout is mainly the use of nonsteroidal anti-inflammatory drugs, corticosteroids and colchicine. Colchicine is a potent anti-inflammatory drug that has a narrow therapeutic index. Indicated for treating gout and familial mediterranean fever, it inhibits mitosis by interfering with microtubule formation and arresting cell division . Analgesics may be prescribed to relieve pain. For prophylaxis, xanthine oxidase inhibitors like Allopurinol and Febuxostat may be given.
Obese patients must be encouraged to reduce weight and to start light, regular exercise. Diet should be low in foods which have a high purine content.
The natural course of gout has 4 stages. First is asymptomatic hyperuricemia which mostly occurs near puberty in males and after menopause in females. After a few years, the second stage, acute gouty arthritis, occurs. This stage is characterized by sudden, excruciating pain, usually in just one joint; 50% occur in the first metatarsophalengeal joint . Eventually other joints become involved. This stage, if left untreated, may last for a few weeks after which gradual resolution occurs, called the asymptomatic intercritical stage.
Now the prognosis varies. The patient may have a second gout attack and progress to the fourth stage called chronic tophaceous gout. Or in some patients, the disease may completely resolve. Overall, with appropriate treatment, gout has a good prognosis.
Patients with gout have as much as 1000 times more uric acid in the body as unaffected individuals do and are almost twice (1.97 times) as likely to develop renal stones as healthy individuals are . They also are prone to develop metabolic syndrome which increases chances of diabetes. Other complications include urate nephropathy due to tophi production in the kidneys resulting in pyelonephritis, recurrent fractures, secondary infections and nerve damage.
The heritability of serum urate levels is estimated at 63% . Gout tends to run in families and several genes have been implicated like URAT1, GLUT9, ABCG2.
Although genetic factors have been strongly associated with hyperuricemia, environmental and other state-of-health factors are responsible for the majority of the gout burden in developed countries . Consumption of fructose-rich foods and beverages is associated with an increased risk of gout in both men and women . Other factors include anemia, obesity, renal insufficiency, cancer and hypertension.
Gout has a high prevalence and is estimated to affect 1-2% population of the United States, and is becoming more common .
It is more common in males.
Gout is more common in some races and rare in others. It is more common in African-Americans than in Whites.
Gout is marked by transient attacks of acute arthritis initiated by crystallization of urates within and about joints. It occurs either due to one of two pathways.
Uric acid is the end product of purine metabolism. One of the pathways involved in purine metabolism is called the salvage pathway in which the enzyme hypoxanthine guanine phosphoribosyl transferase (HGPRT) plays an important role. If this enzyme is deficient, it may lead to increased production of uric acid by the de novo pathway, resulting in gout.
Plasma levels of uric acid are kept within normal range by the four-part excretion system (filtration, reabsorption, secretion and post-secretory reabsorption) of the kidneys. 90% of the filtered urate is reabsorbed by the action of URAT1 gene. Decreased filtration and underexcretion is the primary cause behind gout.
Central to the pathogenesis of the arthritis is precipitation of monosodium nitrate (MSU) crystals into the joints . The synovium is edematous, congested and filled with an inflammatory infiltrate.
Tophi are the pathognomonic hallmark of gout. They are large aggregates of urate crystals surrounded by inflammatory cells and they may occur in joint cavities, articular cartilage, tendons, ligaments, even inside kidneys and skin. This subtype occurs due to repetitive precipitation of urate crystals in acute attacks.
Gout can be prevented by taking a balanced diet which is particularly low in high protein sources such as liver, kidney or sardines, and by avoiding drinks with high sugar content. Lifestyle modifications such as a regular 30 minute walk and weight control can also help.
Gout is defined as an arthritic condition resulting from the deposition of monosodium urate (MSU) crystals in and/or around joints, following long-standing hyperuricemia . It is a very common condition in both developing and developed countries, but fortunately, it can be easily managed.
Gout is a painful inflammatory condition that can affect a variety of joints, causes significant distress and is associated with a number of comorbidities.
Several genetic and environmental factors play a role in causing this disease. Whatever the underlying etiology, gout is primarily due to increased levels of uric acid in blood.
Symptoms include swelling, redness and pain in joints. The most commonly involved joint is of the big toe. Gradually, more joints become involved such as the rest of the toes, instep, ankle, knee, hip, wrist and elbow. In some cases, joints of the vertebrae also become involved.
Treatment includes dietery modifications, lifestyle changes, weight reduction and analgesic and anti-inflammatory medications. Gout can easily be managed.