Thrombophilia/lupus sample handling

[Auntie-D]

I am looking for the official Nice document that referws to doing a long slow spin and a second spin for Lupus samples, rather than a fast spin and microfilter.

 

Where I am now working is acting as a regional reference centre for thrombophilia and lupus testing but isn't handling the samples according to current guidelines. I know the documentation saying not to use microfilters is out there but I cannot find it And the coagulation supervisor will argue black is white rather than be 'wrong'...

 

Can anyone help?

[Auntie-D]

Found it in the Antiphospholipid guidelines

 

Preparation of plasma samples

Blood should be collected into 0·109 mol/l trisodium citrate.

Platelet contamination should be avoided by double

centrifugation at 2000 g for 15 min at 15–22°C. This

should yield plasma with a platelet count of <10 9 109/l.

Plasma filtration through 0·2 lm filters is not recommended

as this may generate microparticles (Favaloro,

2007). Ultracentrifugation (>5000 g) as the second centrifugation

step is not recommended for the same reasons (Sletnes

et al, 1992). Samples should not be repeatedly thawed

and refrozen. Preliminary routine coagulation tests are helpful

in eliminating undiagnosed coagulopathies and anticoagulant

treatment.

 

 

Semin Thromb Hemost 2005; 31(1): 49-58
DOI: 10.1055/s-2005-863805

 

Copyright © 2005 by Thieme Medical Publishers, Inc., 333 Seventh Avenue, New York, NY 10001, USA.

Multilaboratory Testing of Thrombophilia: Current and Past Practice in Australasia as Assessed through the Royal College of Pathologists of Australasia Quality Assurance Program for Hematology

Emmanuel J. Favaloro^{1 ,2} , Roslyn Bonar² , John Sioufi² , Michael Wheeler² , Joyce Low² , Margaret Aboud² , Elizabeth Duncan² , Julian Smith² , Tom Exner² , John Lloyd² , Katherine Marsden²  (on behalf of the RCPA QAP in Haematology) 

[SMILLER]

Yeah.  We do a spin.  Remove plasma.  Spin that, then aliquot the top of that and freeze.  The point being to avoid having too many lipid-laden platelets in the final aliquot.  Frozen platelets get smushed and are going to dump alot of lipids into the plasma.  Not good for a lipid dependent assay.

 

When we got new centrifuges a few years ago, we did document that this method produces platelet-poor plasma.

 

Scott