What is Gout, what are its clinical features and treatment?
Gout is a disease characterised by recurrent attacks of acute pain and swelling first affecting only single joint, mostly metatarso-phalangeal joint of big toe, later becoming polyarticular.It is caused by elevated levels of uric acid in the blood which crystalize and deposited in the joints & surrounding tissues.
Gout
Other names: Acute Gout; Chronic Gout; Gouty Arthritis; Gouty Tophi.
Gout is a disease usually characterised by recurrent attacks of single joint, mostly metatarso-phalangeal joint of big toe, later becoming polyarticular. Although primary gout is the inborn defect of purine metabolism. It is caused by elevated levels of uric acid in the blood which crystallize and deposited in joints & surrounding tissues.
Acute gout is a painful condition typically affects one joint.
Chronic gout is repeated episodes of pain and inflammation, which may involve more than one joint.Aetiology or Causes of Gout :
1. Hereditary Factors: Primary gout is a hereditary disorder. A family history of the disease is seen in 50-80% of cases.
2. Age: The disease is uncommon before the age of 40.
3. Sex: Gout rarely occurs in females.
4. Diet: Previously it was believed that too much intake of foods high in purines was the primary cause of gout. This view is obsolete now a days though some evidence of acute attack may be induced by high intake of purine in the diet.
5. Secondary gout: may occur as a complication of haematological disorders like Polycythaemia and Myelofibrosis & secondary to chlorthiazide group of drugs.Precipitating Factors of Gout :
• Over intake of alcohol
• Idiosyncrasy to certain food
• Secondary to injury
• Excessive aggressive exercise and
• Surgical operations.Pathophysiology of Gout :
Gout is a disorder of purine metabolism and occurs when uric acid crystallises in the form of mono sodium urate, precipitating in joints, on tendons and in the surrounding tissues. The deposits in cartilage and bone lead to absorption of bone and give rise to cysts like appearance or punched-out areas seen in radiographs. There is an inflammatory reaction in the synovial membrane. As disease advances the articular cartilage becomes eroded and thinned. Urates are deposited in the subchondral bone and synovial membrane. Finally the changes of osteoarthritis appear.Clinical Features of gout :
Acute form of gout :
• Big toe is the first joint to be affected in more than 90% of cases.
• Onset is sudden
• Patient commonly awakened through the night by excruciating pain;
• Joint becomes red, swollen, hot and tender;
• Neighbouring veins are distended;
• Appearance of the joint may suggest a pyogenic infection with local cellulites. Gout should always be borne in mind when these symptoms appear for the first time in a middle aged male.
• Pyrexia, sweating, loss of appetite, castigation and scanty highly coloured urine are common symptoms of acute form of gout.
• Blood examination may show a polymorph, leucocytosis and raised ESR.
• After few days the pain decreases.
• Skin over the affected joint becomes scaly & itchy.
• In early stage of the disease the attacks occur at long intervals.
• Between two attacks patient is free from symptoms and radiological examination shows no changes in the affected joint.
• During the acute attack the plasma uric acid is raised, which may return to normal between attacks.
Normal value of plasma uric acid in the male is 2-6mg/100ml. In females it is slightly lower.
Chronic form of gout :
• In case of chronic form of gout attacks occur more often and are of longer duration.
• Finally a stage is reached where relief between the attacks are incomplete and there is persistent pain and stiffness with deformity of the affected joint.
• The arthritis becomes polyarticular, the ankles, hands, and wrists being first affected, then the knees, elbows, shoulders and hips.
• Tophi begin to appear in the periarticular tissues and cartilages of the ears. These consist of deposits of urates of chalky consistency.Complications of Gout :
The complications of gout are as follows:
• In late stages signs of progressive renal failure may appear.
• Urine examination may show proteins, casts, and red blood cells.
• Excessive excretion of urates may lead to calculus formation and attack of renal colic.
• Atherosclerosis and hypertension may complicate the picture and death occurs from coronary thrombosis or cerebral thrombosis.
• In chronic gout the plasma uric acid is continuously high.Diagnosis of Gout :
• Diagnosis is made by a proper history of acute recurring attacks of arthritis with complete remission, usually occurring in a male between 30-50years of age.
• A family history of gout is frequently present.
• In early cases the plasma uric acid may be normal between two attacks.
• Radiological examination is negative.
• In later stages a high plasma uric acid combined with typical radiological findings will clinch the diagnosis.Treatment of Gout :
Acute attacks : In acute attack of gout following medicines are given-
Take non steroidal anti-inflammatory drugs (NSAIDs) such as Ibuprofen Naproxen or Indomethacin as soon as your symptoms begin. Talk to your health care provider about the correct dose. You will need stronger doses for a few days.
Colchicines : is quite effective drug for controlling acute attack of gout but it may cause severe gastro-intestinal upset.
Phenylbutazone: is more effective and drug of choice in the doses of 600mg/day in divided doses for 2-3 days, then reduced to 300mg until subsides.
Corticosteroids : is given in cases which fail to respond phenyl butanone.
Indomethacin : is also effective but it can cause severe headache and gastro intestinal symptoms.
Chronic gout :
Uricosuric agents : Prolonged intake of drugs-
• Increase the excretion of uric acid decrease the number of acute attacks
• A lowering of the blood uric acid
• A decrease in the size of tophi with
• Decrease the incidence of renal damage.
The drug of choice is Probenecid in the dose of 0.5gm 3-4 times daily,
Sulphinpyrazone in the doses of 200-400mg/day.
Salicylates antagonise the action of uricosuric drugs.
Allopurinol : It inhibits the enzyme xanthenes oxidase which converts xanthenes and hypoxanthine to uric acid. Thus serum uric acid level fails and the excretion of its precursors is increased. Serum uric acid can be reduced to normal by a dose of 300mg per day. Allopurinol has no toxic affect, only mild rashes are common.
Special indications for allopurinol are as follows :
1. Severe tophaceous gout,
2. Gout not controlled by uricosuric drugs
3. Intolerance of uricosuric drugs
4. where there is excessive overproduction of uric acid
5. History of repeated uric acid stone production
6. Gout with advanced impairment of renal function and
7. Uric acid nephropathy
Diet : Dietary restrictions are no longer of prime importance in the treatment of gout except in the presence of obesity where diet restriction should be imposed. It has been observed in some patient that attacks of gout are precipitated by consuming certain wines, spirits, or foods rich in purine (sweetbreads, liver, kidney, brain, heart, small fatty fish, fish roe, meat extracts etc.).
Other measures :
In case of damaged or deformed joints the physio-therapeutic measures should be applied. When Tophi becomes large or have ulcerated through skin, they should be removed surgically.Diet and lifestyle :
To prevent the gout following in measures are followed-
• Avoid alcohol/wines.
• Avoid purine rich foods to eat like Anchovies, Sardines, oils, Herring, Organ meat(liver, kidney, sweetbreads),legumes(dried beans & peas), gravies, mushrooms, spinach, asparagus, cauliflower, consommé and baking or brewer' yeast.
• Limit meat intake in each meal
• Avoid fatty food like salad dressings, ice cream and fried foods.
• Eat enough carbohydrates.
• Quick weight loss may cause uric acid kidney stones to form so if you are loosing weight, loose it slowly.Prognosis of gout:
Prognosis of disease is good. By proper treatment of acute attacks lead to live a normal life. Acute form of gout may progress to chronic form of gout.Prevention of gout:
The disease itself may not be preventable, but avoid things that trigger your symptoms. Limit alcohol intake and follow a low purine diet.
Some diet and lifestyle changes may help prevent gouty attacks:
• Avoid alcohol
• Reduce how many purine-rich foods you eat, especially anchovies, sardines, oils, herring, organ meat (liver, kidney, and sweetbreads), legumes (dried beans and peas), gravies, mushrooms, spinach, asparagus, cauliflower, consommé, and baking or brewer's yeast.
• Limit how much meat you eat at each meal.
• Avoid fatty foods such as salad dressings, ice cream, and fried foods.
• Eat enough carbohydrates
• If you are losing weight, lose it slowly. Quick weight loss may cause uric acid kidney stones to form. Differential diagnosis of gout :
• Septic arthritis
• Pseudo-gout
• Rheumatoid arthritis
Gouty Tophi when not located in a joint can be mistaken for Basal cell carcinoma or other neoplasm.