URIC ACID

• Uric acid is the end product of purine metabolism.

• U.A is a chemical compound that is produced after the breakdown of purines in the body.

• U.C is excreted by kidney in large amount & intestinal tract in small amount.

· Purines:

• Purines are organic compounds found in various foods, such as red meat, organ meats, seafood, and certain vegetables.

URIC ACID METABOLISM & EXCRETION

• Uric acid metabolism and excretion involve a series of Steps in the body.

• The following steps in this process are:

• 1. Purine Metabolism:

  • Uric acid is produced as a byproduct of purine metabolism.

  • Purines are organic compounds found in certain foods and are also produced by the body itself.

  • When purines are broken down, they form uric acid.

• 2. Production of Uric Acid:

  • Purine nucleotides, which are building blocks of DNA and RNA, are metabolized into a compound called xanthine.

  • Xanthine is further broken down by the enzyme xanthine oxidase, resulting in the production of uric acid.

• 3. Uric Acid in the Bloodstream:

  • Uric acid enters the bloodstream and is transported throughout the body.

  • It is carried by proteins, mainly albumin, in the blood.

• 4. Uric Acid Filtered by the Kidneys:

  • The majority of uric acid is filtered by the kidneys, which act as the primary route for its excretion.

  • The glomeruli, tiny structures in the kidneys, filter uric acid from the blood into the urine.

• 5. Reabsorption and Secretion:

  • After filtration, some of the filtered uric acid is reabsorbed back into the bloodstream by the renal tubules.

  • Small amount is actively secreted into the tubules, enhancing its elimination.

• 6. Uric Acid in the Urine:

  • The excreted uric acid combines with other waste products and water to form urine. It is then eliminated from the body during urination.

• 7. Gastrointestinal Excretion:

  • A small portion of uric acid is excreted through the gastrointestinal tract. It is eliminated in the feces after being metabolized by gut bacteria.

CAUSES OF URIC ACID

• Some common type of uric acid causes are –

• a. Increased purine synthesis:

  • Person with genetic or metabolic factors that lead to excessive production of purines, which are broken down into uric acid.

• b. Dietary purine intake:

  • Consuming foods such as red meat, organ meats, seafood & certain vegetables can increase uric acid levels.

• c. Alcohol consumption:

  • Alcohol, particularly beer, can interfere with uric acid excretion and increase its production & cause hyperuricemia.

• d. Kidney dysfunction:

  • Reduced kidney function can impair the excretion of uric acid from the body.

• e. Medications:

  • Some medications can interfere with the excretion of uric acid, leading to its buildup in the body such as diuretics.

• f. Certain cancers:

  • Leukemia, lymphoma, and certain solid tumors can cause increased uric acid production due to rapid cell turnover and breakdown.

• g. Hypothyroidism:

  • Underactive thyroid function can contribute to hyperuricemia by reducing the excretion of uric acid.

RISK FACTOR FOR INCREASE U.A

• Some common factor include:

• a. Gender and age:

  • Men generally have higher uric acid levels than women.

  • However after menopause, women's uric acid levels may increase.

• b. Genetic factors:

  • Inherited genetic abnormalities can affect uric acid metabolism and contribute to hyperuricemia.

• c. Rapid weight loss or fasting:

  • These conditions can temporarily increase uric acid levels as the breakdown of body tissues releases purines.

• d. Metabolic syndrome:

  • Conditions such as –

  • Obesity

  • High blood pressure

  • *Insulin resistance

  • Dyslipidemia

• e. Diet:

  • High purine intake

  • High fructose intake

COMPLICATIONS

• The most common complications associated with hyperuricemia are:

• a. Gout:

  • Gout is a painful and inflammatory arthritis that occurs when uric acid crystals deposit in joints.

  • It may cause sudden and severe joint pain, swelling, redness & warmth.

  • Gout commonly affects the big toe but can also affect other joints like the ankles, knees, wrists, and fingers.

• b. Kidney Stones:

  • High levels of uric acid in the urine can lead to the formation of uric acid crystals, which can accumulate and form kidney stones.

• c. Kidney Disease:

  • Prolonged hyperuricemia can contribute to the development of chronic kidney disease.

  • Uric acid crystals can accumulate in the kidneys, leading to inflammation, damage to the renal tubules, and impaired kidney function.

• d. Cardiovascular Disease:

  • Elevated uric acid levels have been associated with an increased risk of developing cardiovascular diseases such as hypertension, coronary artery disease, & stroke.

• e. Joint Damage and Deformity:

  • Repeated gout attacks can cause progressive joint damage and deformity, lead to chronic joint pain, stiffness & reduced mobility.

• f. Tophi Formation:

  • Tophi are collections of uric acid crystals that can form under the skin, usually in cooler areas of the body like the fingers, elbows, and ears.

DIAGNOSIS

• Diagnosis of uric acid level typically involves a combination of medical history assessment, physical examination & laboratory tests.

• To diagnose uric acid levels, a blood test known as a "serum uric acid test" is typically performed

• 1. Medical History:

  • Your doctor will inquire about your symptoms, medical history & family history of gout or other related conditions.

  • They may ask about your diet, alcohol consumption, medications, and any recent illnesses or injuries.

• 2. Laboratory Tests:

  • Serum Uric Acid Test: A blood test performed to measure the level of uric acid in your blood.

  • Joint Fluid Analysis: If you have fluid buildup in a joint, the doctor may perform a joint aspiration, which involves removing a small sample of the joint fluid. The fluid is then examined under a microscope to check for the presence of urate crystalsc.

  • Kidney Function Tests: Since the kidneys play a crucial role in excreting uric acid, kidney function tests may be conducted to evaluate how well your kidneys are functioning. This may involve blood tests and urine tests.

• 3. Imaging Tests:

• It may include:

  • X-rays

  • Ultrasound

  • CT scan

• 4. Other Tests:

• These may include

  • Complete blood count (CBC)

  • Liver function tests

  • Lipid profile

  • Glucose levels

TREATMENT

• a. Dietary Changes:

  • Consuming a balanced diet that includes low-fat dairy products, complex carbohydrates, fruits, and vegetables.

  • Maintaining proper hydration by drinking an adequate amount of water is also important.

• b. Weight Management:

  • Losing weight if overweight or obese can help lower uric acid levels.

• c. Alcohol consumption:

  • Limiting alcohol consumption, especially beer, which is known to increase uric acid production.

• d. Regular Exercise:

  • Regular physical activity can aid in weight management and overall health.

  • It can also help lower uric acid levels and reduce the risk of gout attacks.

• e. Medications:

  • Medicine taken in hyperuricemia -

  • Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

  • Colchicine

  • Corticosteroids

  • Urate-Lowering Therapy.

NORMAL RANGE OF URIC ACID

Ø MALES : 3.4 – 7.0 mg/dl

Ø FEMALES : 2.5 – 6.0 mg/dl

• Mg/dl – milligrams per deciliter

• µmol/L - micromoles per liter

CLINICAL SIGNIFICANCE:

• a. Increased level seen in –

  • Gout

  • Arthritis

  • Impaired renal function

  • Starvation

• b. Decreased level seen in –

  • Wilson’s disease

  • Fanconis syndrome

  • Yellow atrophy of liver

About author

Himanshu Paneru is the founder and author of DOC NOTE MASTER,

a platform dedicated to sharing insightful articles on medical topics

and education. Currently pursuing a master’s degree in Medical

microbiology at Netaji subhash chandra bose sybharti medical

college Dehradun, Uttarakhand. Himanshu combines his academic

knowledge with a passion for writing.