Welcome clotting researchers to the Haematex Newsletter - June 2019



THOUGHT WE WERE DONE WITH DOACs? NAH!


We are very grateful to Dr Emmanuel Favaloro for including our DOAC neutralizing agent in a recent RCPA-QAP survey and publishing the results. "Neutralising rivaroxaban induced interference in laboratory testing for lupus anticoagulant (LA): A comparative study using DOAC-Stop™ and Andexanet alfa" is now available in Thrombosis Research. It's free before July 20 via the link: https://authors.elsevier.com/a/1Z8tw_17tKTX09

This paper showed that "DOAC-Stop™ was able to neutralise the rivaroxaban effect, normalising LA screen times and ratios, LA confirm times and ratios and final LA screen/confirm ratios. With DOAC-Stop™, all participants in this study effectively identified the sample as LA negative, despite the wide variety of instruments, methodologies and reagents in use". The other agent was not quite as effective.

DOAC-Stop™ is widening its potential applications. "Clotting tests correlate better with DOAC concentrations when expressed as a "Correction Ratio": results before/after extraction with the DOAC-Stop™ reagent" is now in Thrombosis Research, vol.179:69-72. There will be a few posters on it and similar products at the ISTH meeting. We hope to see you there. A Victorian Pathology lab is the first in Australia to implement DOAC-Stop™ in AT and Lupus assays. Other labs are currently setting up. Great to have Australians behind Australian developed technology and products! Thank you!




FOR ANYONE STILL LIVING ON WARFARIN


In our Hornsby area magazine "Bush Telegraph", we found advertised a new book of recipes by a local author just for those on warfarin, available from: https://www.healthylivingwithwarfarin.com.au/
Any suggestions for a DOAC cookbook?




HOW ARE WE DOING? YOUR HONEST FEEDBACK


Tell us what you think of us and don't hold back! All submissions are anonymous and will be considered by us. We appreciate your time! https://www.surveymonkey.com/r/3MK3FWQ




RECOMMENDATIONS FOR FACTOR ASSAY MEASUREMENT (OSCA or chromogenics?)


We've brought it up a few times before, but now that new clotting factor concentrates (CFC) have come on the scene we found a recent article recommending chromogenic testing for FVIII and FIX over one stage clotting assays (OSCAs). It has emerged that the type of activator used in APTT tests in combination with the CFC may result in over or underestimation of the result. By using chromogenic assays, the variable of patient plasma components affecting the clot is removed. There are only two currently available chromogenic assays for FIX, one being the Biophen Chromogenic FIX kit, although the article suggests there is limited data on the performance of these assays, it does state the rFIXFc can only be correctly measured with the Biophen (of course available through Haematex).

The article also states that the National Haemophilia Foundation (of the USA) recommends chromogenic FVIII and FIX assays be made more widely available in coagulation laboratories.

"Laboratory assay measurement of modified clotting factor concentrates: a review of the literature and recommendations for practice". G.A.Young. J Thromb Haemostas.2019;17: https://doi.org/10.1111/jth.14394




REFERENCE LAB GUIDE
ANTI-THROMBOTIC DIAGNOSTICS


This reference lab guide is available for use in your laboratory. Produced by Hyphen BioMed and Haematex. Please click to download the image.