[Histonet] New antibody diluent

[Terri Braud]

CAP specifically addresses Scott's question in the checklist (see below, copied from the Checklist)
ANP.22780
Laboratories confirm assay performance when conditions change that may affect performance.
NOTE: A change in antibody clone requires full revalidation/verification of the assay (equivalent to initial analytic validation/verification - see ANP.22750).
Laboratories must confirm assay performance with at least when an existing validated/verified assay has changed in any of the following ways: antibody dilution, antibody vendor (same clone), or the incubation or retrieval times (same method).

So, according to CAP, each antibody with the new diluent would have to confirm with at least two known positive and two known negative cases.
What a pain! (IMHO)

Terri L. Braud, HT(ASCP)
Anatomic Pathology Supervisor
HNL Labs, Holy Redeemer Hospital
1648 Huntingdon Pike
Meadowbrook, PA 19046
ph: 215-938-3689
fax: 215-938-3874
Care, Comfort, and Heal

   3. Re: Antibody diluent (Lindrud, Scott)

Message: 3
Date: Thu, 25 Mar 2021 12:30:25 +0000
From: "Lindrud, Scott" <Scott.Lindrud at carrishealth.com>
Subject: Re: [Histonet] Antibody diluent

What is everyone's take on what needs to be done from a verification/validation standpoint if you switch diluents for your concentrated antibodies?  The CAP summary of recommendations on the validation IHC antibodies doesn't specifically mention the changing of diluent as one of the variables.
If I change the diluent on my ER and Her2 concentrates, do I need to do a complete re-validation or just a quick verification using a few positive and negative cases?  I'm not really liking the idea of a complete re-validation!
Thanks for any info!
Scott
Scott A. Lindrud, MLSCM(ASCP)CTCM  | Histopathology Technical Specalist/Cytotechnologist
P: 320-231-4520
F: 320-231-4503
scott.lindrud at carrishealth.com

Rice Memorial Hospital
301 Becker Ave SW
Willmar, MN 56201