Uric acid and its salts are end products of the purine metabolism.
With progressive renal insufficiency, there is retention in blood of
urea, creatinine and uric acid.
Elevate uric acid level may be indicative of renal insufficiency and is
commonly associated with gout1,5,6.Clinical diagnosis should not be made on a single test result; it should
integrate clinical and other laboratory data.
STORAGE AND STABILITY
All the components of the kit are stable until the expiration date on the
label when stored tightly closed at 2-8ºC, protected from light and
contaminations prevented during their use.
Do not use reagents over the expiration date.
Signs of reagent deterioration:
- Presence of particles and turbidity.
- Blank absorbance (A) at 520 nm ≥ 0,16.
ADDITIONAL EQUIPMENT
Spectrophotometer or colorimeter measuring at 520 nm.
- Matched cuvettes 1,0 cm light path.
- General laboratory equipment.
SAMPLES
Serum or plasma1: Stability 3-5 days at 2-8ºC or 6 months at –20ºC.
Urine (24 h)1: Stability 4 days at 15-25ºC, pH 8. Dilute sample 1/50
in distilled water. Mix. Multiply results by 50 (dilution factor); If urine
is cloudy; warm the specimen to 60ºC for 10 min to dissolve
precipitated urates and uric acid. Do not refrigerate.
QUALITY CONTROL
Control sera are recommended to monitor the performance of assay procedures:
SPINTROL H Normal and Pathologic (Ref. 1002120 and 1002210).
If control values are found outside the defined range, check the instrument,
reagents and calibrator for problems.
Each laboratory should establish its own Quality Control scheme and corrective
actions if controls do not meet the acceptable tolerances.
INTERFERENCES
No interferences were observed to bilirubin up to 170 µmol/L, hemoglobin
up to 130 mg/dL and ascorbic acid up to 570 µmol/L2.
A list of drugs and other interfering substances with uric acid determination
has been reported 3,4.
NOTES
URIC ACID CAL: Proceed carefully with this product because due its
nature it can get contaminated easily.
Calibration with the aqueous standard may cause a systematic error in
automatic procedures. In these cases, it is recommended to use a
serum Calibrator.
Use clean disposable pipette tips for its dispensation.
SPINREACT has instruction sheets for several automatic
analyzers. Instructions for many of them are available on request.
