double determination of phenotype

[dboutin]

I wonder if it is mandatory to make a phenotype determination twice on two separate draw in order to consider it confirmed.

Is somebody know ? If yes, which standard or regulation requires that ?

Thanks

[galvania]

It is mandatory in France - not that that helps much for the States!

[dboutin]

Thank you, Merci,

Savez-vous quelle norme ou réglement européen rend cette pratique obligatoire ?

Do you know which european standard or regulations that makes it mandatory ?

Thanks, Merci.

[dcross]

In Australia, we phenotype donors on two separate donations before considering the phenotype confirmed. We follow the Code of Europe but, I have checked, and this requirement is not form the Code of Europe (12th ed).

I am not sure where we derived this practice from but I believe it to be necessary as mistakes in phenotyping do happen.

David

[galvania]

Thank you, Merci,

Savez-vous quelle norme ou réglement européen rend cette pratique obligatoire ?

Do you know which european standard or regulations that makes it mandatory ?

Thanks, Merci.

Yes - it's the Arrêté du 26 Avril 2002 modifiant l'arrêté du 26 novembre 1999 relatif à la bonne exécution des analyses de biologie médicale, section 2.2.1-

"Une réalisation du phénotypage RH-KEL 1 comporte obligatoirement l'utilisation des réactifs anti-RH2, anti-RH3, anti-RH4, anti-RH5, anti-KEL 1 et du (des) réactif(s) témoin(s) adéquat(s). Il est recommandé d'utiliser des réactifs d'origine monoclonale.

..Sa définition est fonction des conditions techniques:

-si les opérations....sont strictement réalisées dans des conditions d'automation et d'informatisation décrites à l'article IV.....une détermination repose sur une seule réalisation executée à l'aide d'un lot de réactifs et par un technicien;

-dans tous les autres cas, une détermination repose sur deux réalisations executées pas deux techniciens différents. La saisie manuelle des résultats doit aussi passer par une double saisie effectuée par deux personnes différentes.

...Un phénotypage...valide est réalisé sur deux prélèvements différents à raison d'une détermination par prélèvement."

The other part of this document that is relevant is Annexe D III

"La validation analytique repose sur:

-résultats conformes des CQI;

-absence d'ambiguïté réactionelle avec chaque réactif;

.........

-absence de discordance entre deux réalisations;........."

Sorry this is all in French, it's a direct quote. In translation (for anyone who's interested) the relevant text is the decree of 26th April.....relative to the correct carrying out of biomedical analyses.

The carrying out of a phenotype for Rh and Kell has to include anti-C, c, E, e and K as well as adequate control reagents. It is recommended to use monoclonal reagents.

How the phenotype is carried out depends on the technical conditions:

If the phenotype, including all the operations relative to verification and registration of samples..are carried out according to the guidelines laid out in Article IV Automation and IT (this is a very long, complicated document that lays down strict guidelines for working with Automates - Anna) then the determination of a phenotype can be carried out on a single sample with one lot of reagents and by one single technician;

-in all other cases, a determination requires 2 determinations carried out by 2 different technicians. Manual reading must also be carried out by two different technicians.

A valid Rh/K phenotype is carried out on 2 different samples, with one test being carried out on each sample.

Then, from Annexe D III -

The validation of the test requires:

-correct Quality control results

-Clear positive or negative results with each reagent

......

-There must be no discrepancy between the two determinations.....

Phew!! Hope that helps

[dboutin]

In Australia, we phenotype donors on two separate donations before considering the phenotype confirmed. We follow the Code of Europe but, I have checked, and this requirement is not form the Code of Europe (12th ed).

I am not sure where we derived this practice from but I believe it to be necessary as mistakes in phenotyping do happen.

David

Thanks ! dboutin:)

[dboutin]

Yes - it's the Arrêté du 26 Avril 2002 modifiant l'arrêté du 26 novembre 1999 relatif à la bonne exécution des analyses de biologie médicale, section 2.2.1-

"Une réalisation du phénotypage RH-KEL 1 comporte obligatoirement l'utilisation des réactifs anti-RH2, anti-RH3, anti-RH4, anti-RH5, anti-KEL 1 et du (des) réactif(s) témoin(s) adéquat(s). Il est recommandé d'utiliser des réactifs d'origine monoclonale.

..Sa définition est fonction des conditions techniques:

-si les opérations....sont strictement réalisées dans des conditions d'automation et d'informatisation décrites à l'article IV.....une détermination repose sur une seule réalisation executée à l'aide d'un lot de réactifs et par un technicien;

-dans tous les autres cas, une détermination repose sur deux réalisations executées pas deux techniciens différents. La saisie manuelle des résultats doit aussi passer par une double saisie effectuée par deux personnes différentes.

...Un phénotypage...valide est réalisé sur deux prélèvements différents à raison d'une détermination par prélèvement."

The other part of this document that is relevant is Annexe D III

"La validation analytique repose sur:

-résultats conformes des CQI;

-absence d'ambiguïté réactionelle avec chaque réactif;

.........

-absence de discordance entre deux réalisations;........."

Sorry this is all in French, it's a direct quote. In translation (for anyone who's interested) the relevant text is the decree of 26th April.....relative to the correct carrying out of biomedical analyses.

The carrying out of a phenotype for Rh and Kell has to include anti-C, c, E, e and K as well as adequate control reagents. It is recommended to use monoclonal reagents.

How the phenotype is carried out depends on the technical conditions:

If the phenotype, including all the operations relative to verification and registration of samples..are carried out according to the guidelines laid out in Article IV Automation and IT (this is a very long, complicated document that lays down strict guidelines for working with Automates - Anna) then the determination of a phenotype can be carried out on a single sample with one lot of reagents and by one single technician;

-in all other cases, a determination requires 2 determinations carried out by 2 different technicians. Manual reading must also be carried out by two different technicians.

A valid Rh/K phenotype is carried out on 2 different samples, with one test being carried out on each sample.

Then, from Annexe D III -

The validation of the test requires:

-correct Quality control results

-Clear positive or negative results with each reagent

......

-There must be no discrepancy between the two determinations.....

Phew!! Hope that helps

Thanks for your time and yes it helped a lot. dboutin

[dcross]

Yes - it's the Arrêté du 26 Avril 2002 modifiant l'arrêté du 26 novembre 1999 relatif à la bonne exécution des analyses de biologie médicale, section 2.2.1-...

Is this from a Council of Europe document? If so, which one?

David

[galvania]

Is this from a Council of Europe document? If so, which one?

No. In Europe, each member country is supposed to use the council of europe recommendations to produce individual guidelines or proscriptions for their own country. The Council of Europe Guidelines are a sort of minimal requirement. In France, there is a specific government body that then produces these decrees which have legal status; the extract I quoted is one of these. A similar system exists in Italy, but I could not find a requirement to carry out a double determination for the Rh phenotype.

I have also found the relevant passage in the UK guidelines, which might be a bit more relevant - and in English!!.

'Annexe 4 - General specifications for laboratory test procedures

A4.2 Additional Rh and k phenotyping and other extended phenotyping

...Red cell components should only be labelled with confirmed extended phenotypes. A confirmed phenotype is one where the typing has been carried out in duplicate on the current donation or once on the current donation and is in agreement with historic data from previous donations.....'

[OPUS104]

Dumb Question from me here. Are we talking for immediate transfusion in a hospital....or permenant donor record in a donor center......or "this unit only" record in a donor center?

[dboutin]

Dumb Question from me here. Are we talking for immediate transfusion in a hospital....or permenant donor record in a donor center......or "this unit only" record in a donor center?

My question was originally for a donnor record ? dboutin

[Malcolm Needs ☆]

My question was originally for a donnor record ? dboutin

For donors in the UK, we type each time they donate (unless the grouping reagent is incredibly rare), but where the donor has been genotyped, a confirmation a second time is sufficient for the rest of their "donation" lives (if you see what I mean).

:)