1. DR. ABDULRAHMAN AL-AJLAN
Uric acid
DR. ABDULRAHMAN AL-AJLAN

2. Uric acid
Acid is a waste product that results from normal body processes and is also found in some foods. Normally, the kidneys eliminate uric acid from the body in urine.
A build up of uric acid in the body may cause kidney stones, kidney damage, or a form of arthritis called gout. This may occur when the body produces too much uric acid or when the kidneys cannot eliminate uric acid adequately.
Medication and diet changes can reduce the amount of uric acid in the body.

3. Gout
Gout is an inflammatory joint disease that causes acute pain and swelling. It is a form of arthritis that develops when uric acid crystals form in and around the joints; commonly affecting the big toe joint (this symptom is called podagra).
Gout causes warmth, pain, swelling, redness, and extreme tenderness of the affected joint, and it may cause chills and fever. Gout may involve other joints of the feet, ankles, knees, wrists, fingers, and elbows.

4. Inherited factors (genes) may play a role in a person's risk for developing high uric acid levels. Gout can seem to flare up without specific cause or can be brought on by factors such as being overweight, eating meats and seafood that are high in chemicals called purines, taking certain medications (especially aspirin and diuretics), and drinking too much alcohol.
Symptoms of gout usually begin suddenly, often at night, and the pain may be severe. Chronic gout may cause painless nodules (tophi) to develop under the skin. Without treatment, gout attacks tend to recur and may cause severe damage to joints, tendons, and other tissues. Gout usually can be successfully treated with medication.

5. Tophi
Tophi are chalky, gritty accumulations of uric acid crystals that build up in the soft tissue of a gouty joint, often occurring in the elbow or the joints of fingers or toes. Tophi develop if gout is not treated for an extended period of time, redness, and warmth (inflammation).
Progressive crippling and destruction of cartilage and bone is possible. Care and
advances in the early treatment of gout have made this stage of gout uncommon.

6. Kidney stones
Kidney stones (renal calculi or nephrolithiasis) are pieces of minerals that form in the kidneys. They are usually painless while they remain in the kidney, but they can cause severe pain as they break loose and travel through narrow tubes (ureters) to exit the body during urination.
Symptoms of a kidney stone include severe pain on one side of the back. Other symptoms include blood in the urine (hematuria), painful or frequent urination (dysuria), and nausea and vomiting.

7. A kidney stone is usually treated by increasing fluid intake and taking medications to relieve pain until the stone has passed. This typically occurs within a few days. If the stone seems unlikely to pass on its own or is causing severe pain, treatment options include a shock wave treatment (lithotripsy), which can break up a large stone into smaller pieces that are easier to pass, or rarely, surgery.

8. There are four different types of kidney stones, and they can be as small as grains of sand or as large as a golf ball. Kidney stones occur most often in adults and are rare in children.

9. Normal
Normal values of blood uric acid may vary from lab to lab.
Uric acid in blood
Men:
3.5–7.2 milligrams per deciliter (mg/dL)
Women:
2.6–6.0 mg/dL
Children:
2.0–5.5 mg/dL

10. Greater-than-normal values
Higher-than-normal levels of uric acid in the blood do not necessarily mean that you have gout. Your symptoms and other medical information will be considered along with the results of your uric acid blood test.
Increased levels of uric acid in the blood indicate an increased risk for developing gout. Also, if a joint (often the big toe) is acutely swollen and painful, increased levels of blood uric acid strongly suggest that gout is present.

11. High levels of uric acid may indicate that kidney disease or kidney damage is preventing the removal of uric acid from the blood.
Increased levels of uric acid can also be caused by the increased breakdown of body cells that occurs with some types of cancer (including leukemia, lymphoma, and multiple myeloma) or cancer treatments, hemolytic anemia, sickle cell anemia, or heart failure. Other conditions that can increase uric acid levels in the blood include alcohol dependence, preeclampsia, liver disease (such as cirrhosis), lipid disorders (such as hyperlipidemia), obesity, psoriasis, hypothyroidism, and low blood levels of parathyroid hormone.

12. Starvation, malnutrition, or lead poisoning can also increase the amount of uric acid in the blood.
High levels of blood uric acid may also indicate a rare inherited chromosomal disorder called Lesch- Nyhan syndrome, which is characterized by high levels of uric acid in the blood and urine, delayed growth, mental retardation, and sometimes self- destructive behavior.
 diet can also cause low levels of uric acid in the blood.
Some people lose more uric acid through the urine, resulting in low levels of uric acid in the blood.

13. What Affects the Test
Many medications may increase the level of uric acid in the blood. These include diuretics, theophylline (such as Theo-dur, Theo-X, Theochron), aspirin (in low doses), and some medications used to treat tuberculosis.
Excessive use of alcohol, starvation, a high-protein diet, stress, or strenuous exercise can raise the level of uric acid in the blood.
Many medications may decrease the level of uric acid in the blood. These include aspirin (in high doses), corticosteroids, probenecid (Benemid, Probalan), and allopurinol (Aloprim, Zyloprim).

14. The vitamin niacin, high doses of vitamin C, caffeine, and a substance found in chocolate and tea (theobromine) can cause uric acid levels to be inaccurately high.
Rough handling, contamination, or inadequate refrigeration of the blood sample can cause inaccurate test results.

15. What To Think About
Uric acid may also be measured in urine. If your blood uric acid level is high, a 24- hour urine collection may help determine whether your body is producing too much uric acid or your kidneys are not excreting enough of it. For more information, see the medical test Uric Acid in Urine.

16. A high level of uric acid in the blood does not always mean that a person with a painful joint has gout. Testing the fluid taken from an affected joint for the presence of uric acid crystals is the only sure method to diagnose gout. For more information, see the medical test
Joint Fluid Analysis.

17. Uric acid blood levels vary from day to day
Uric acid blood levels vary from day to day. The level is usually higher in the morning and lower in the evening.
Increasing levels of blood uric acid in a pregnant woman, even if the levels remain within the normal range, may help diagnose preeclampsia.