Adjustment of lactate dehydrogenase concentration results according to the haemolysis index following in vitro haemolysis.

In the presence of haemolysis, the interpretation of the Lactate dehydrogenase (LDH) activity result is a major operational challenge for medical laboratories: if the origin is intravascular, then the measurement will reflect the clinical reality, but in extravascular haemolysis, the laboratory will be confronted with an artefactual increase leading to false-positive high results. The aim of our study was to evaluate the adjustment of LDH concentration results according to the haemolysis index (HI). After designed a mathematical model to correct the LDH measured as a function of the haemolysis index using a Cobas 8000 analyser (Roche diagnostics, Mannheim, Germany), LDH measurement of seventy-four duplicate samples were tested before and after exposure to extravascular haemolysis process.

Evaluation of total leukocytes count by flow cytometry with Beckman Coulter® DXH900 in the presence of platelet aggregates.

The Beckman Coulter® DXH900 uses the impedance method to measure the total leukocytes count. In presence of platelet aggregates, the device identifies the structural changes and associates an alarm with the leukocytes result. The aim of this study was to evaluate the influence of platelet aggregates using the principle of flow cytometry as a second assessment of the white blood cell count.

Study of haemolysis interference limit on serum potassium assay on Roche Cobas 8000 and evaluation of corrected potassium.

Roche Diagnostics decided a more restrictive haemolysis index (≤20 HI) for approval the release of serum potassium results. This study examined the risk of overestimating serum potassium results related to the HI according to the Ricos total error (±5.6%) and evaluated the approach of Martinez-Morillo and Alvarez to determine a corrected potassium.

Quality planning and control strategy for AQT90 flex Radiometer in point of care testing.

In the context of point of care testing (PoCT) and ISO 22870, internal quality control (IQC) is a crucial part of PoCT accreditation processes. Quality Control materials shall be periodically examined with a frequency that is based on the robustness of the analytical procedure and the risk of harm to the patient from an erroneous result. We propose to apply the statistical quality control (SQC) procedure to develop an individualized QC plan for AQT90 flex instrument used in PoCT.