Original Article

Ann Lab Med 2015; 35(3): 341-347

Published online May 1, 2015

Copyright © Korean Society for Laboratory Medicine.

Scoring System for Detecting Spurious Hemolysis in Anticoagulated Blood Specimens

Gilsung Yoo, M.D., Juwon Kim, M.D., Young Uh, M.D., Kwang Ro Yoon, Ph.D., Soon Deok Park, Ph.D., and Kap Jun Yoon, M.D.

Department of Laboratory Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea

Correspondence to: Young Uh
Department of Laboratory Medicine, Yonsei University Wonju College of Medicine, 20 Ilsan-ro, Wonju 220-701, Korea
Tel: +82-33-741-1592
Fax: +82-33-731-0506

Received: August 18, 2014; Revised: September 17, 2014; Accepted: January 12, 2015

This is an Open Access article distributed under the terms of the Creative Commons Attribution Non-Commercial License ( which permits unrestricted non-commercial use, distribution, and reproduction in any medium, provided the original work is properly cited.


Background: The identification of in vitro hemolysis (IVH) using a hematology analyzer is challenging because centrifugation of the specimens cannot be performed for cell counts. In the present study, we aimed to develop a scoring system to help identify the presence of hemolysis in anticoagulated blood specimens.
Methods: Thirty-seven potassium EDTA anticoagulated blood specimens were obtained, and each specimen was divided into 3 aliquots (A, B, and C). Aliquots B and C were mechanically hemolyzed by aspirating 2 and 5 times, respectively, using a 27-gauge needle and then tested; aliquot A was analyzed immediately without any hemolysis. After the cells were counted, aliquots B and C were centrifuged and the supernatants were tested for the hemolytic index and lactate dehydrogenase levels.
Results: The 4 hematologic parameters were selected and scored from 0 to 3 as follows:<34.0, 34.0-36.2, 36.3-38.4, and ≥38.5 for mean cell hemoglobin concentration (MCHC, g/dL); <0.02, 0.02, 0.03, and ≥0.04 for red blood cell ghosts (1012/L); <0.13, 0.13-0.38, 0.39-1.30, and ≥1.31 for difference value (g/dL) of measured hemoglobin and calculated hemoglobin; and <0.26, 0.26-0.95, 0.96-3.34, and ≥3.35 for difference value (g/dL) of MCHC and cell hemoglobin concentration mean. The hemolysis score was calculated by adding all the scores from the 4 parameters. At the cutoff hemolysis score of 3, the IVH of aliquots B and C were detected as 64.9% and 91.9%, respectively.
Conclusions: The scoring system might provide effective screening for detecting spurious IVH.

Keywords: Hemolysis, Score, System, Anticoagulants, Analyzer