Influence of hemolysis on routine clinical chemistry testing.

Author(s): Lippi G, Salvagno GL, Montagnana M, Brocco G, Guidi GC

Publication: Clin Chem Lab Med, 2006, Vol. 44, Page 311-6

PubMed ID: 16519604 PubMed Review Paper? No

Purpose of Paper

Conclusion of Paper

Studies

1. Study Purpose

   The purpose of this study was to determine the effects of hemolysis on the measurement of common clinical chemistry analytes. Hemolysis was achieved by subjecting whole blood to an overnight freeze-thaw cycle, mixing it with serum that was also frozen overnight (-70 degrees C), and subsequently using this mixture for serial dilution of fresh blood specimens. Resulting fresh serum specimens contained free hemoglobin levels between 0 and 20.6 g/L.

   Summary of Findings:

   As expected, subjecting whole blood to an overnight freeze-thaw cycle lowered white blood cell, platelet, and erythrocyte counts beyond the analytical sensitivity of the analyzer. Hemolysis interference with the measurement of clinical chemistry analytes was generally linear and led to overestimation of alanine amino transferase (ALT), creatinine, AST, creatine kinase (CK), iron, LDH, magnesium, potassium, lipase, phosphorus, and urea nitrogen and underestimation of albumin, alkaline phosphatase (ALP), chloride, gamma-glutamyltransferase (GGT), sodium, and uric acid. AST, chloride, LDH, sodium, and potassium levels were the most affected by free serum hemoglobin. Calcium, total bilirubin, and glucose showed no clinically significant changes in specimens containing added levels of free hemoglobin compared to those with no hemolysis.

   Biospecimens

   • Bodily Fluid - Blood
   • Bodily Fluid - Serum

   Preservative Types

   • None (Fresh)
   • Frozen

   Diagnoses:

   • Normal

   Platform:

   Analyte	Technology Platform
   Protein	Spectrophotometry
   Protein	Clinical chemistry/auto analyzer
   Small molecule	Clinical chemistry/auto analyzer
   Electrolyte/Metal	Clinical chemistry/auto analyzer
   Carbohydrate	Clinical chemistry/auto analyzer
   Protein	Hematology/ auto analyzer
   Cell count/volume	Hematology/ auto analyzer

   Pre-analytical Factors:

   Classification	Pre-analytical Factor	Value(s)
   Biospecimen Aliquots and Components	Biospecimen components	0 g/L serum hemoglobin 0.16 g/L serum hemoglobin 0.3 g/L serum hemoglobin 0.6 g/L serum hemoglobin 1.3 g/L serum hemoglobin 2.6 g/L serum hemoglobin 5.1 g/L serum hemoglobin 10.3 g/L serum hemoglobin 20.6 g/L serum hemoglobin
   Biospecimen Preservation	Type of fixation/preservation	Frozen None (fresh)
   Biospecimen Aliquots and Components	Hemolysis	Freeze/thaw-induced Hemolysate added No hemolysate added

   View more