Welcome clotting experts to the Haematex Newsletter-August 2016

TIRED OF POKEMON?


Lupus anticoagulant (LA) testing- people are doing it all over the place. The new kit on the block is the Hyphen HEMOCLOT LA-S (#CK090K) and corresponding LA-C (#CK091K). These are dilute Russell's Viper Venom Tests for the more specific detection of LA, the former being the screen and the latter is the confirm reagent. These CE-marked reagents provide reliable results for LA even in patients on warfarin and DOACS. (See for example; Depreter B, Devreese K. Dilute Russell's viper venom time reagents in lupus aanticoagulant testing: a well-considered choice. Clin.Chem.Lab.Med. 2016 aop. Please note that we agree with these researchers results on specificity but not necessarily on LA sensitivity).

To complement these reagents is a new LA Control Plasma Set #SC081K (set of weak and strong positives 2 x 6 x 0.5ml). For Control 1(weak LA), the mean normalised ratio is in the range of 1.25-1.50 and C2 (strong LA) is 1.8-2.4 on STA-R analysers (different results could be obtained when used with kits other than the HEMOCLOT LA-S AND LA-C). These kits are straight out of production and pricing is yet to come but certain to be more economical than current popular reagents.

Note that Hyphen also have platelet poor normal plasma ideal for mixing tests in 5ml vials. Biophen Normal Plasma 5 (8 x 5ml vials, ref 223605).


ONE FOR THE HAEMOPHILIA CENTRES…


For detecting anti FVIII antibodies in acquired haemophilia, a newly published study from the Hanover Medical School showed that Factor VIII (FVIII) binding IgG detected by ELISA could be an alternative to the Nijmegen-modified Bethesda assay (NBA). This is the diagnostic reference standard for detecting neutralizing autoantibodies against FVIII, but is technically inconvenient. It is also not ideal for quantifying the complex type 2 inhibitors seen in acquired hemophilia, and suffers from high inter-laboratory variability.

The Hanover study validated the use of the ZYMUTEST Anti VIII IgG ELISA kit as a tool for detecting anti-FVIII IgG autoantibodies and diagnosing Aquired Hemophilia A (AHA). AHA is a severe bleeding disorder that requires fast and accurate diagnosis as it occurs often unexpectedly in previously healthy men and women of every age.

This assay is probably easier to perform, less difficult to interpret and less expensive than the NBA under most circumstances. Therefore, this assay may be an alternative tool to diagnose AHA. Anti-FVIII IgG as quantified by the ELISA may also provide useful prognostic information. (Werwitzke S. et al. Diagnostic and prognostic value of factor VIII binding antibodies in acquired hemophilia A: data from the GTH-AH 01/2010 study. J Thromb Haemost. 2016 May;14(5):940-7)

ZYMUTEST Anti VIII IgG MonoStrip IgG - #RK039A (kit of 32 tests)


and…ONE FOR THE ARACHNOPHOBES


Arachidonic Acid is not scary but is an omega-3 fatty acid widely used as an aggregating reagent for use in platelet aggregation studies in human plasma. When added to normal PRP, it induces thromboxane A2 generation and granule release leading to the first platelet shape change. It is considered a strong agonist.

The Hyphen reagent for platelet aggregation assay using Arachidonic Acid was recently improved in order to offer an optimized quantitative gradation between patient presenting a low platelet aggregation and those with a normal one. Only the new formulation will now be available, the reference number and the kit presentation will remain the same (#AG003K, 3 x 0.5 mL).


CREATIVE NEW HAEMATEX PRODUCT RANGE


Always with an ear to the ground to create interesting specialised coagulation products such as DOAC-test, we are constantly revising our product range to cater to what your lab needs. From collagen to DOAC tests, have a look at our current selection (attached) and you might find exactly what you've been looking for and at a great price!