The Basic Evaluation of Revohem™ APTT SLA in the Automated Blood Coagulation Analyzer CN™‐6000

• The Basic Evaluation of Revohem™ APTT SLA in the Automated Blood Coagulation Analyzer CN™‐6000

AUTHOR(S)

Daiki SHIMOMURA^*1, Aya KOUNO^*1, Tokio TAKATA^*1, Akimi TAKADA^*1,
Kaori UEDA^*2, Osamu KUMANO^*3, Masashi SHIMADA^*1 and Mikio KAMIOKA^*1

*1 Department of Laboratory Medicine, Tenri Hospital
*2 Osaka Branch, Sysmex Corporation
*3 HYPHEN BioMed, SAS

SUMMARY

The basic performance of the newly developed reagent Revohem™ APTT SLA (Sysmex Corporation, Kobe, Japan; hereinafter Rev, Sysmex) was evaluated. The results of within-run precision, between-day precision and on-board stability were good, and lot-to-lot variability was also acceptable. The reference interval established by 136 samples was a little lower than that of Thrombocheck APTTSLA (Sysmex; hereinafter TC) as the reference reagent. The coagulation factor sensitivity of Rev was higher than that of TC at lowactivity range in factor V, VIII, IX, X, and XII by in vitro examination using artificial deficient plasma. A comparison between Rev and TC obtained in vivo clinical samples was also performed. The clotting times of Rev were more prolonged than TC in factor VIII deficiency and inhibitor with less than 1%; it indicated that the sensitivity of Rev was higher in low activity of factor VIII. Although the clotting times of liver disease samples in Rev were shorter than TC, the ratio calculated from the mean of 35 normal samples was similar to that of TC. The clotting times of lupus anticoagulant (LA) samples in Rev were significantly longer than those of TC and the correlation against dilute Russell’s viper venom time (dRVVT) was good; it indicated that the sensitivity of Rev was higher. While the reactivity to unfractionated heparin examined in vitro spiked samples showed Rev had much higher reactivity than TC, the discrepancy became smaller in the examination of in vivo clinical heparin samples, and Rev showed about 1.2-fold value of TC in the heparin sample with more than 0.3 IU/mL. In the samples from patients taking direct oral anticoagulants (DOACs), the correlation between Rev and TC was good, and it was recognized that the clotting times were dependent on the drug concentrations. The correlations between APTT clotting times and drug concentrations in rivaroxaban, apixaban and edoxaban were poor. While the clotting times and ratios of Rev were lower than those of TC in argatroban samples, the reactivity to nafamostat mesylate was higher in Rev, Rev showed good repeatability and smaller lot-to-lot variability, and it was considered that the reagent was acceptable for data management. The data indicated that the sensitivity to LA and factor deficiency in low activity was high and it would be useful as a screening reagent. On the other hand, the sensitivity to some drugs was different from TC, especially for unfractionated heparin, and it was recognized that there was a discrepancy over 0.3 IU/mL concentration. It is important to obtain the data between current and new reagents and confirm the difference in clinical samples. It is also important to notify medical doctors of these data if necessary.

KEY WORDS

Activated Partial Thromboplastin Time (APTT), Synthetic Phospholipids, Ellagic Acid, CN-6000

NOTE(S)

This article represents users' experiences with Sysmex solutions. Details on the validated intended use can be found in the Sysmex instructions for use of the corresponding products.
The specifications, performances and functions described here may vary depending on the region or the country due to the regulatory affairs, legal matters, or local guidelines. For more details, please contact your local Sysmex office or distributor.
This article is translated and republished from the Sysmex Journal Web Vol.22 No.2, 2021. (Japanese)