Uric Acid, Blood

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Uric Acid, Blood

Synonym/acronym: Urate.

Common use

To monitor uric acid levels during treatment for gout and evaluation of tissue destruction, liver damage, renal function, and monitor the effectiveness of therapeutic interventions.


Serum (1 mL) collected in a gold-, red-, or red/gray-top tube. Plasma (1 mL) collected in a green-top (heparin) tube is also acceptable. Note: Rasburicase will rapidly decrease uric acid in specimens left at room temperature. If patients are receiving this medication, collect the blood sample in a prechilled green-top (heparin) tube and transport in an ice slurry.

Normal findings

(Method: Spectrophotometry)
AgeConventional UnitsSI Units (Conventional Units × 0.059)
1–30 d
 Male1.3–4.9 mg/dL0.08–0.29 mmol/L
 Female1.4–6.2 mg/dL0.08–0.37 mmol/L
1–3 mo
 Male1.4–5.3 mg/dL0.08–0.31 mmol/L
 Female1.4–5.8 mg/dL0.08–0.34 mmol/L
4–12 mo
 Male1.5–6.4 mg/dL0.09–0.38 mmol/L
 Female1.4–6.2 mg/dL0.08–0.37 mmol/L
1–3 yr
 Male & female1.8–5 mg/dL0.11–0.3 mmol/L
4–6 yr
 Male & female2.2–4.7 mg/dL0.13–0.28 mmol/L
7–9 yr
 Male & female2–5 mg/dL0.12–0.3 mmol/L
10–12 yr
 Male & female2.3–5.9 mg/dL0.14–0.35 mmol/L
13–15 yr
 Male3.1–7 mg/dL0.18–0.41 mmol/L
 Female2.3–6.4 mg/dL0.14–0.38 mmol/L
16–18 yr
 Male2.1–7.6 mg/dL0.12–0.45 mmol/L
 Female2.4–6.6 mg/dL0.14–0.39 mmol/L
19 yr–Adult
 Male4–8 mg/dL0.24—0.47 mmol/L
 Female2.5–7 mg/dL0.15–0.41 mmol/L
Adult older than 60 yr
 Male4.2–8.2 mg/dL0.25–0.48 mmol/L
 Female3.5–7.3 mg/dL0.21–0.43 mmol/L
Therapeutic target for patients with gout: Less than 6 mg/dL (SI: Less than 0.4 mmol/L).


Uric acid is the end product of purine metabolism. Purines are important constituents of nucleic acids; purine turnover occurs continuously in the body, producing substantial amounts of uric acid even in the absence of purine intake from dietary sources such as organ meats (e.g., liver, thymus gland and/or pancreas [sweetbreads], kidney), legumes, and yeasts. Uric acid is filtered, absorbed, and secreted by the kidneys and is a common constituent of urine. Serum urate levels are affected by the amount of uric acid produced and by the efficiency of renal excretion. Values can vary based on diet, gender, body size, level of exercise, level of stress, and regularity in consumption of alcohol. Elevated uric acid levels can indicate conditions of critical cellular injury or destruction; hyperuricemia has an association with hypertension, hypertriglyceridemia, obesity, myocardial infarct, renal disease, and diabetes. Rasburicase is a medication used in the treatment and prevention of acute hyperuricemia related to tumor lysis syndrome in children and for leukemias and lymphomas related to the toxic effects of chemotherapy. Rasburicase is a recombinant form of uricase oxidase, an enzyme that converts uric acid to allantoin, a much more soluble and effectively excreted substance than uric acid.

This procedure is contraindicated for



  • Assist in the diagnosis of gout when there is a family history (autosomal dominant genetic disorder) or signs and symptoms of gout, indicated by elevated uric acid levels
  • Determine the cause of known or suspected renal calculi
  • Evaluate the extent of tissue destruction in infection, starvation, excessive exercise, malignancies, chemotherapy, or radiation therapy
  • Evaluate possible liver damage in eclampsia, indicated by elevated uric acid levels
  • Monitor the effects of drugs known to alter uric acid levels, either as a side effect or as a therapeutic effect

Potential diagnosis

Increased in

  • Conditions that result in high cellular turnover release nucleic acids into circulation, which are converted to uric acid by the liver.

  • Acute tissue destruction as a result of starvation or excessive exercise (related to cellular destruction)
  • Alcoholism
  • Chemotherapy and radiation therapy (related to high cellular turnover)
  • Chronic lead toxicity (cellular destruction related to hemolysis)
  • Congestive heart failure (related to cellular destruction)
  • Diabetes (decreased renal excretion results in increased blood levels)
  • Down syndrome
  • Eclampsia
  • Excessive dietary purines (purines are nucleic acid bases converted to uric acid by the liver)
  • Glucose-6-phosphate dehydrogenase deficiency (cellular destruction related to hemolysis)
  • Gout (usually related to excess dietary intake)
  • Hyperparathyroidism
  • Hypertension (related to effects on renal excretion)
  • Hypoparathyroidism (related to disturbances in calcium and phosphorus homeostasis)
  • Lactic acidosis (cellular destruction related to shock)
  • Lead poisoning (cellular destruction related to hemolysis)
  • Lesch-Nyhan syndrome (related to disorder of uric acid metabolism)
  • Multiple myeloma (related to high cell turnover)
  • Pernicious anemia (cellular destruction related to hemolysis)
  • Polycystic kidney disease (related to decreased renal excretion, which results in increased blood levels)
  • Polycythemia (related to increased cellular destruction)
  • Psoriasis
  • Sickle cell anemia (cellular destruction related to hemolysis)
  • Tumors (related to high cell turnover)
  • Type III hyperlipidemia

Decreased in

    Fanconi’s syndrome (related to increased renal excretion) Low-purine diet (related to insufficient nutrients for liver to synthesize uric acid) Severe liver disease (uric acid synthesis occurs in the liver) Wilson’s disease (affects normal liver function and is related to impaired tubular absorption)

Critical findings

  • Adults
  • Greater than 13 mg/dL (SI: Greater than 0.8 mmol/L)
  • Children
  • Greater than 12 mg/dL (SI: Greater than 0.7 mmol/L)
  • Note and immediately report to the health-care provider (HCP) any critically increased or decreased values and related symptoms especially fluid imbalance.

  • It is essential that a critical finding be communicated immediately to the requesting health-care provider (HCP). A listing of these findings varies among facilities.

  • Timely notification of a critical finding for lab or diagnostic studies is a role expectation of the professional nurse. Notification processes will vary among facilities. Upon receipt of the critical value the information should be read back to the caller to verify accuracy. Most policies require immediate notification of the primary HCP, Hospitalist, or on-call HCP. Reported information includes the patient’s name, unique identifiers, critical value, name of the person giving the report, and name of the person receiving the report. Documentation of notification should be made in the medical record with the name of the HCP notified, time and date of notification, and any orders received. Any delay in a timely report of a critical finding may require completion of a notification form with review by Risk Management.

  • Symptoms of acute renal dysfunction and/or failure associated with hyperuricemia include altered mental status, nausea and vomiting, fluid overload, pericarditis, and seizures. Prophylactic measures against the development of hyperuricemia should be undertaken before initiation of chemotherapy. Possible interventions include discontinuing medications that increase serum urate levels or produce acidic urine (e.g., thiazides and salicylates); administration of fluids with sodium bicarbonate as an additive to IV solutions to promote hydration and alkalinization of the urine to a pH greater than 7; administration of allopurinol 1 to 2 days before chemotherapy; monitoring of serum electrolyte, uric acid, phosphorus, calcium, and creatinine levels; and monitoring for ureteral obstruction by urate calculi using computed tomography or ultrasound studies. Possible interventions for advanced renal insufficiency and subsequent renal failure may include peritoneal dialysis or hemodialysis.

Interfering factors

  • Drugs and substances that may increase uric acid levels include acetylsalicylic acid (low doses), aldatense, aminothiadiazole, anabolic steroids, antineoplastic agents, atenolol, azathioprine, azathymine, azauridine, chlorambucil, chlorthalidone, cisplatin, corn oil, cyclosporine, cyclothiazide, cytarabine, diapamide, diuretics, ethacrynic acid, ethambutol, ethoxzolamide, flumethiazide, hydrochlorothiazide, hydroflumethiazide, ibufenac, ibuprofen, levarterenol, mefruside, mercaptopurine, methicillin, methotrexate, methoxyflurane, methyclothiazide, mitomycin, morinamide, polythiazide, prednisone, pyrazinamide, quinethazone, salicylate, spironolactone, tacrolimus, theophylline, thiazide diuretics, thioguanine, thiotepa, triamterene, trichlormethiazide, vincristine, and warfarin.
  • Drugs that may decrease uric acid levels include allopurinol, aspirin (high doses), azathioprine, benzbromaron, benziodarone, canola oil, chlorothiazide (given IV), chlorpromazine, chlorprothixene, cinchophen, clofibrate, corticosteroids, corticotropin, coumarin, dicumarol, enalapril, fenofibrate, flufenamic acid, guaifenesin, iodipamide, iodopyracet, iopanoic acid, ipodate, lisinopril, mefenamic acid, mersalyl, methotrexate, oxyphenbutazone, phenindione, phenolsulfonphthalein, probenecid, radiographic agents, rasburicase, seclazone, sulfinpyrazone, and verapamil.
  • Rasburicase will rapidly decrease uric acid in specimens left at room temperature. Specimens must be collected in prechilled tubes, transported in an ice slurry, and tested within 4 hr of collection.

Nursing Implications and Procedure

Potential nursing problems

ProblemSigns & SymptomsInterventions
Fluid volume (Related to decreased glomerial filtration or the resence of the diuretic stage of renal disease)Overload: edema, shortness of breath, increased weight, ascites, rales, rhonchi, and diluted laboratory values. Deficit: decreased urinary output, fatigue, sunken eyes, dark urine, decreased blood pressure, increased heart rate, and altered mental statusManage underlying cause of fluid alteration; record accurate intake and output; monitor urine characteristics and respiratory status; establish baseline assessment data; collaborate to adjust oral and IV fluids to provide optimal hydration status
Confusion (Related to an alteration in fluid and electrolytes, hepatic disease, renal disease)Disorganized thinking, restlessness, irritability, altered concentration and attention span, changeable mental function over the day, hallucinationsTreat the medical condition; correlate confusion with the need to reverse altered electrolytes; evaluate medications; prevent falls and injury through appropriate use of postural support, bed alarm, or restraints; consider pharmacological interventions; record accurate intake and output to assess fluid status
Electrolytes (Related to compromised excretion; renal function)Increased BUN, increased creatinine; decreased sodium, increased urine specific gravity; increased potassium; decreased sodium; decreased calcium; increased magnesium; increased phosphorus; altered uric acidMonitor laboratory values; administer appropriate IV infusions and medications to correct altered electrolytes as ordered; collaborate with physician in consideration of dialysis as appropriate to maintain homeostasis; monitor uric acid levels
Nutrition (Related to altered taste, decreased food intake, nausea, vomiting)Poor nutrition with inadequate caloric intake; progressive weight loss; decreasing muscle mass; thin, weak, and apathetic; poor skin turgor with breakdown; difficulty healing; anemic; decreased respiratory and cardiac statusAssess nutritional requirements; seek a consult with the registered dietician; use a calorie count; correlate baseline nutritional intake with medical status; consider individual and cultural food preferences; collaborate with physician, pharmacist, and clinical dietician in consideration of enteral and parenteral nutrition


  • Positively identify the patient using at least two unique identifiers before providing care, treatment, or services.
  • Patient Teaching: Inform the patient this test can assist in diagnosing gout and assessing kidney function.
  • Obtain a history of the patient’s complaints, including a list of known allergens, especially allergies or sensitivities to latex. Especially note pain and edema in joints and great toe (caused by precipitation of sodium urates), headache, fatigue, decreased urinary output, and hypertension.
  • Obtain a history of the patient’s genitourinary, hepatobiliary, and musculoskeletal systems; symptoms; and results of previously performed laboratory tests and diagnostic and surgical procedures.
  • Obtain a list of the patient’s current medications, including herbs, nutritional supplements, and nutraceuticals (see Effects of Natural Products on Laboratory Values online at DavisPlus).
  • Review the procedure with the patient. Inform the patient that specimen collection takes approximately 5 to 10 min. Address concerns about pain and explain that there may be some discomfort during the venipuncture.
  • Sensitivity to social and cultural issues, as well as concern for modesty, is important in providing psychological support before, during, and after the procedure.
  • Note that there are no food, fluid, or medication restrictions unless by medical direction.


  • Potential complications: N/A
  • Avoid the use of equipment containing latex if the patient has a history of allergic reaction to latex.
  • Instruct the patient to cooperate fully and to follow directions. Direct the patient to breathe normally and to avoid unnecessary movement.
  • Observe standard precautions, and follow the general guidelines in Patient Preparation and Specimen Collection. Positively identify the patient, and label the appropriate specimen container with the corresponding patient demographics, initials of the person collecting the specimen, date, and time of collection. Perform a venipuncture.
  • Remove the needle and apply direct pressure with dry gauze to stop bleeding. Observe/assess venipuncture site for bleeding or hematoma formation and secure gauze with adhesive bandage.
  • Promptly transport the specimen to the laboratory for processing and analysis.


  • Inform the patient that a report of the results will be made available to the requesting health-care provider (HCP), who will discuss the results with the patient.
  • Nutritional Considerations: Increased uric acid levels may be associated with the formation of kidney stones. Educate the patient, if appropriate, on the importance of drinking a sufficient amount of water when kidney stones are suspected.
  • Nutritional Considerations: Increased uric acid levels may be associated with gout. Nutritional therapy may be appropriate for some patients identified as having gout. Educate the patient that foods high in oxalic acid include caffeinated beverages, raw blackberries, gooseberries and plums, whole-wheat bread, beets, carrots, beans, rhubarb, spinach, dry cocoa, and Ovaltine. Foods high in purines include organ meats, which should be restricted. In other cases, the requesting HCP may not prescribe a low-purine or purine-restricted diet for treatment of gout because medications can control the condition easily and effectively.
  • Recognize anxiety related to test results. Discuss the implications of abnormal test results on the patient’s lifestyle. Provide teaching and information regarding the clinical implications of the test results, as appropriate.
  • Reinforce information given by the patient’s HCP regarding further testing, treatment, or referral to another HCP. Answer any questions or address any concerns voiced by the patient or family.
  • Depending on the results of this procedure, additional testing may be performed to evaluate or monitor progression of the disease process and determine the need for a change in therapy. Evaluate test results in relation to the patient’s symptoms and other tests performed.
  • Patient Education

    • Discuss lifestyle alterations that may improve health.
    • Provide written and verbal information on the anatomy and physiology of the disease process.
  • Expected Patient Outcomes

    • Knowledge
    • States understanding of the importance of recognizing and reporting disease signs and symptoms to HCP
    • Verbalizes food selections that are appropriate to health maintenance
    • Skills
    • Demonstrates proficiency in performing and recording daily weight
    • Demonstrates proficiency in self-administration of medication for gout after meals as appropriate
    • Attitude
    • Expresses willingness to make necessary lifestyle changes to improve health management
    • Complies with the recommended therapeutic plan of care

Related Monographs

  • Related tests include arthroscopy, biopsy bone marrow, calcium, calculus kidney stone panel, cholesterol, collagen cross-linked telopeptide, CBC, CBC RBC count, CBC RBC indices, CBC RBC morphology, creatinine, creatinine clearance, gastrin stimulation, G6PD, lactic acid, lead, PTH, parathyroid scan, phosphorus, sickle cell screen, synovial fluid analysis, UA, US abdomen, and uric acid urine.
  • Refer to the Genitourinary, Hepatobiliary, and Musculoskeletal systems tables at the end of the book for related tests by body system.
Handbook of Laboratory and Diagnostic Tests, © 2013 Farlex and Partners