Coombs Serum Validation

[johna]

For anyone who has changed from rabbit to monoclonal Coombs serum reagents I was wondering if you saw any need to validate the monoclonals? It seems pointless to me since they are basically generic equivalents and are quality controlled through daily reagent QC as well as the use of Coombs control cells. Any comments would be appreciated.

[adiescast]

We did not do a validation for the same reasons.

[Kochman]

Depending on the monoclonal reagent you are using, it could be different than the rabbit material you are used to. I would recommend doing some level of validation.

[luhubert]

I would run 20 tests in duplicate - you could do Screening Cell 2 on your QC twice every day for 20 days using Rabbit IgG on one tube and Monoclonal on the other. Keep the results in a validation folder to show anyone who asks. If the results are not the same in all 20 tests, you have to do at least 20 from the different one so that you end up with 20 alike. It really isn't very difficult and shows you didn't just "pop it in" without checking.

[Dawn]

According to a researcher who works for a leading BB reagent manufacturer, if you use the reagent according to the manufacturer's directions there is no need for validation, only QC must be done.

[Kochman]

Sorry, but checking with a researcher at a reagent manufacturing facility will not always give you the best regulatory answer.

The concept of validation is based on the fact that no two testing facilities are exactly alike. Validation is supposed to show that you can make the reagent work properly (meet performance specifications/expectations) in your own facility, with your own staff, your own instruments, your own adjunct reagents (for example - saline), following your SOPs, etc. I know that CAP expects you to validate and I assume JAHCO expects it, too.

It is difficult to give detailed guidance on validation when someone asks since, as stated above, every situation is different. In general, you should think about your extremes and test at each extreme. For example, if you know your "room temperature" varies between 18 and 25 C, you should test at 18 and at 25. If testing works at both extremes, it is presumed it will work in between. Likewise you should consider things like run/batch sizes (smallest and largest), incubator temperature variability/stability, size/volume and number of sample drops, etc. The list is too long to cover here and not all variables are applicable to each validation situation. That's why you should sit down and develop a validation plan first and then go about your testing.

In this specific case (validation of change to monoclonal anti-human globulin), consider doing parallel antibody screening and identification using the range of antibodies you normally see or "worst case" antibodies like anti-Fyb, anti-Jka and anti-Jkb. Also consider parallel DATs and weak D tests. If you do both hand washing and machine washing, test using both methods.

Hope this helps instead of scaring you.