salicylate in serum/plasma
Indications
- evaluation of salicylate toxicity
Reference interval
Principle
SALICYLATE IN SERUM & PLASMA, DUPONT'S ACA IV
The salicylate (SAL) method for the ACA is a modification of the Trinder colorimetric technique.
Under acidic conditions, ferric nitrate forms a complex with salicylate in the SAL-2 measuring pack. The absorbance at 510 nm due to the complex formed in proportional to the salicylate concentration in the serum. The SAL-1 pack provides a serum- reagent blank at the same wavelength
H+ Salicylate + Fe(NO3)3 ---------------> Salicylate-Fe3+ complex (non-absorbing at 510 nm) (absorbs at 510 nm)
SALICYLATE IN SERUM, KODAK EKTACHEM 700 ANALYZER
The Kodak Ektachem Clinical Chemistry Slide (SALI) is a dry, multilayered, self-contained analytical element coated on a transparent polyester support.
A 10 uL drop of sample is deposited on the slide & is evenly distributed by the spreading layer. Salicylate in the sample is oxidatively decarboxylated to catechol. Catechol is oxidized by tyrosinase to o-quinone, which couples with MBTH to produce a dye. The amount of dye is proportional to the concentration of salicylate in the sample. The intensity of the dye is measured by reflectance spectrophotometry.
Salicylate Salicylate + NADH Hydroxylase Catechol + CO2 + H+ + O2 --------------> + NAD+ + H2O
Tyrosinase Catechol + MBTH + O2 -------------> Red Dye Complex
Salicylate Salicylate + NADH Hydroxylase Catechol + CO2 + H+ + O2 --------------> + NAD+ + H2O
Tyrosinase Catechol + MBTH + O2 -------------> Red Dye Complex
Clinical significance
See salicylate for adverse effects & toxicity (overdose).
Salicylate belongs to a class of analgesic, antipyretic & anti- inflammatory drugs that include aspirin. Treatment is primarily directed at correction of the acid-base, electrolyte, and water abnormalities. Excretion of the drug by the kidneys can be increased by administration of sodium bicarbonate solutions intravenously. In some cases exchange transfusion or hemodialysis is required to remove salicylate more quickly.
In patients on chronic therapy, small dose changes may produce disproportionate changes in serum levels. Steady-state concentrations for an individual patient on chronic salicylate therapy are not adequately predicted from nomograms or standard dose schedules. In salicylate poisoning the following symptoms may occur: initial alkalosis followed by acidosis in the blood, ketosis & possible elevated plasma glucose. Glucose should be measured when levels of salicylate over 24 mg/dL are detected.
Specimen
SALICYLATE IN SERUM & PLASMA, DUPONT'S ACA IV
Patient Preparation: No special patient preparation is required.
- Serum: Serum is the specimen of choice. Serum should be collected in a red top vacutainer by venipuncture. Serum should be separated from the red cells after centrifugation & hemolyzed specimens should be avoided. Serum samples can be stored at room temperature for several hours, & frozen at -20 C samples are stable for at least 1 (one) year.
- Plasma: Plasma specimens are also acceptable. Plasma should be collected in a green top vacutainer containing sodium heparin by venipuncture. The effects of other anticoagulants on the test have not been evaluated. Specimen can be stored at room temperature for several hours & frozen at -20 C for 1 (one) year.
Minimum sample size 0.6 mL: with an optimum size of 1.5 mL or larger.
SALICYLATE IN SERUM, KODAK EKTACHEM 700 ANALYZER
Patient Preparation: No special patient preparation is required.
For serum preparation: Collect whole blood & allow to clot according to manufacturer's instructions. Specimens are collected in a red top vacutainer by venipuncture & should be separated immediately from the cells & analyze as soon as possible.
Special Precautions:
Tube stoppers in contact with blood can be a source of contamination in toxicology/therapeutic drug monitoring. Testing based upon the NCCLS Guidelines has indicated that specimens collected in red- or pink-stoppered Terumo Venoject blood collection tubes should not be used with this salicylate method.
If not analyzed immediately, refrigerate the specimen at 2 to 8 degrees C. Freeze the specimens for long-term storage or shipment.
Minimum sample size 0.5 mL: with an optimum size of 1.0 mL or larger.
More general terms
More specific terms
Additional terms
Component of
References
- ↑ Kaplan, L., & Pesce, A., Clinical Chemistry:theory, analysis, & correlation, C. V. Mosby Co., St. Louis, MO., 1984, pp. 1384.
- ↑ Tietz, N., Fundamentals of Clinical Chemistry, 3rd edition W. B. Saunders Co., Philadelphia, 1987, pp. 897.
- ↑ Tietz, N., Textbook of Clinical Chemistry, W. B. Saunders Co., Philadelphia, 1986, pp. 1725.
- ↑ ACA IV Discrete Clinical Analyzer Instrument Manual, Volume 1:Operation, DuPont Company, Wilmington, Delaware, 1984.
- ↑ ACA IV Discrete Clinical Analyzer Instrument Manual, Volume 3:Chemistry, DuPont Company, Wilmington, Delaware, 1984.
- ↑ Kodak Ektachem Package Inserts, Kodak Clinical Products, Rochester, New York, 1991.
- ↑ Clinical Significance of Tests Available on the DuPont Automatic Clinical Analyzer, DuPont Company, Wilmington Delaware, p. 73.
- ↑ Kodak Ektachem 700 Clinical Analyzer Operator's Manual, Kodak Clinical Products, Rochester, New York.
- ↑ Kodak Ektachem 700 Training Manual, Kodak Clinical Products, Rochester, New York.
- ↑ Collection Containers for Specimens for Toxicological Analysis, Order Code H31-P, National Committee for Clinical Laboratory Standards, Vol 6(4), pp. 121-129, 1986.
- ↑ Tietz, N. W.: Fundamentals of Clinical Chemistry, W. B. Saunders Co., Philadelphia, PA, pp. 897-898, 1987.
- ↑ Young, D. S.: Effects of Drugs on Clinical Laboratory Tests, Washington, D. C.; AACC Press, 1990.
- ↑ Mayo Clinic: Salicylate, Serum http://www.mayomedicallaboratories.com/test-catalog/Clinical+and+Interpretive/8480
- ↑ Salicylate Laboratory Test Directory ARUP: http://www.aruplab.com/guides/ug/tests/0090251.jsp