2023 Volume 72 Issue 2 Pages 236-242
Platelet aggregation is an important laboratory finding because it affects blood counts. In this study, we evaluated two cases in which the platelet aggregation flag “PLT-clumps?”was undetectable on the device, despite the presence of markedly large platelet aggregates. In the same way as in the present case, we verified using heparin-treated blood the discrepancy between platelet aggregation images and “PLT-clumps?”. The results showed the same discrepancy of results as in the present case after 20 min of blood collection. A comparison between the results obtained 10 min after blood collection and those obtained 20 min after showed a predominant increase in the number of platelets in platelet aggregates in the latter. Therefore, we inferred that the cause of the discrepancy was the number of platelets in the platelet aggregates. It is then suggested that when the platelet aggregate diameter increased owing to an increase in the number of platelets in the platelet aggregate, the device did not recognize the platelet aggregates as platelets, and “PLT-clumps?” were undetectable. Therefore, the discrepancy between platelet aggregation images and “PLT-clumps?” may occur in the case of large platelet aggregates.
