Effects of Spectral Interfering Substances on Light Transmission Platelet Aggregation Using Infrared Based...

This study aims to investigate the nature and extent of hemolyzed, icteric, or lipemic (HIL) interference on platelet aggregation (PA) using the TA-8 V aggregometer (Diagnostica Stago, Asnière sur Seine) equipped with a near infrared light source outside the typical absorbance range of HIL.

Platelet-Rich-Plasma (PRP) samples were spiked with substances mimicking HIL interference: red blood cell hemolysate (RBCH; 0.3-20 g/L of hemoglobin), bilirubin (15-400 mg/L), and a fat emulsion (Intralipid 20%: 0.5-3 g/L). Maximal intensity (MaxInt) and velocity (Vel) were recorded in the basal state and in response to ADP 5 μmol/L and collagen 2 μg/mL. RBCH solution was treated with apyrase 0.1 U/mL.

Spontaneous aggregation appeared above 0.6 g/L RBCH and significantly intensified with increased RBCH concentrations. The addition of apyrase to RBCH prevented spontaneous aggregation regardless of the RBCH concentration and led to reduced interindividual variability. In response to ADP and collagen, MaxInt and Vel significantly decreased as apyrase-treated RBCH concentrations increased. MaxInt and Vel in response to ADP or collagen were not affected by increasing concentrations of bilirubin. The presence of lipids significantly increases MaxInt in response to ADP or collagen starting at 0.5 g/L.

Our findings suggest that PA testing using the TA-8 V instrument is not significantly impacted by icterus and hyperlipidemia within the specified ranges in healthy individuals. However, it is crucial to reject grossly hemolysed samples (exceeding 0.6 g/L) to avoid interference with ADP released from red blood cells. Further research is needed to confirm these results in patients with platelet dysfunction.