Effects of hemolysis interferences on routine biochemistry parameters

Hemolysis is still the most common reason for rejecting samples, while reobtaining a new sample is an important problem. The aim of this study was to investigate the effects of hemolysis in different hemolysis levels for mostly used biochemical parameters to prevent unnecessary rejections.

Sixteen healthy volunteers were enrolled in the study. Four hemolysis levels were constituted according to hemoglobin concentrations and they were divided into five groups: Group I: 0-0.10 g/L, Group II:0.10-0.50 g/L, Group III: 0.51-1.00 g/L, Group IV: 1.01-2.50 g/L, Group V: 2.51-4.50 g/L. Lysis was achieved by mechanical trauma.

Hemolysis interference affected lactate dehydrogenase (LD) and aspartate aminotransferase (AST) almost at undetectable hemolysis by visual inspection (plasma hemoglobin < 0.5 g/L). Clinically meaningful variations of potassium and total bilirubin were observed in moderately hemolyzed samples (hemoglobin > 1 g/L). Alanine aminotransferase (ALT), cholesterol, gamma glutamyltransferase (GGT), and inorganic phosphate (P) concentrations were not interfered up to severely hemolyzed levels (hemoglobin: 2.5-4.5 g/L). Albumin, alkaline phosphatase (ALP), amylase, chloride, HDL-cholesterol, creatine kinase (CK), glucose, magnesium, total protein, triglycerides, unsaturated iron binding capacity (UIBC) and uric acid differences were statistically significant, but remained within the CLIA limits.

To avoid preanalytical visual inspection for hemolysis detection, improper sample rejection, and/or rerun because of hemolysis, it is recommended in this study that, routine determination of plasma or serum free hemoglobin concentrations is important. For the analytes interfered with hemolysis, new samples have to be requested.