NPNs: Uric Acid

Major Product of Purine Catabolism

Purine is made from

Pyrimidine

Formed from xanthine oxidase from liver and intestine

Uric acid exist as _________ urates in plasma

> 6.8 g of urate crystals may form

Organic Meat Legumes Plant

Confirms and Monitor Gout

diagnosis of Renal Calculi using Uric Acid uses what specimen

Uric acid can be used to monitor Uric Acid Nephropathy in cancer patient that undergoes chemotherapy

Uric Acid Crystals: Reference Value Male Female

Gout Increased Nuclear Metabolism Chronic Renal Disease Lesch Nyhan Syndrome

• Occurs in male between 3rd and 5th decade of life • Negative birefringence crystals in synovial fluid • acute inflammatory arthritis • can lead to nephrothiliasis

Seen in leukemia, Lymphoma, MM and PV, Hemolytic and Megaloblastic Anemia Treatment: Allupurinol

Decreased GFR and tubular secretion BUA >10 mg/dL

Inborn Error of Purine Metabolism

Orange sand diaper syndrome ; deficiency of HGPT (Hypoxanthine Guanin Phosphoribosyl Transferase

Seen in patient with Preeclampsia

Treatment for Hyperuricemia: Inhibits xanthine oxidase activity ; lowering UA in serum without affecting excretion in kidney

Treatment for Hyperuricemia: Drugs that lower the serum UA but increase excretion of UA in urine = Prone to uric acid stones if not maintained at Alk pH.

Treatment for Hyperuricemia: • Neither excretion nor production is affected • Alters phagocytic effect of leukocytes in uric acid crystals in tissues • used in symptomatic patients

• Fanconi Syndrome • Wilson’s disease • Hodgkin’s disease • Overtreatment of Allopurinol • Chemotherapy with azathioprine / 6-mercaptopurine • Liver Disease

Laboratory Methods for Uric Acid: Chemical Method that uses Principle: Redox Reaction

Laboratory Methods for Uric Acid: Product produced in Caraway Method / Phosphotungstic Acid Method