As we finally move to automated gel, is there any reason to keep doing auto controls with panels? Can we just run a DAT instead? If you do this do you routinely charge for the DAT?

ProVue (and I assume VISION) has two different panel tests that you can order.  You can elect to run a panel A, panel B or panel C with or without an auto control.

30 minutes ago, Mabel Adams said:

If you do this do you routinely charge for the DAT?

It stands to reason that if your medical director determined that this would be the route to go and it became your standard protocol for antibody identification testing that you would charge for it.

I've always thought that we did an auto control instead of a DAT because it was more like the screen (in the old days) or ID testing we were doing--just add one more tube and put in patient cells and plasma and voila.  It seems like the DAT is really what we want to know about and there isn't any convenience aspect if it is on an automated machine so why not just start with the DAT?  I just wanted to make sure others were doing this.

An auto-control and a DAT have not always given the same result in my experience!

I've seen positive autocontrols with negative DAT's, just curious if anyone has seen positive DATs with a negative autocontrol? I have always performed an autocontrol first and if the autocontrol is positive then we go to a DAT.

We find lots of auto controls positive in gel but the tube DATs are negative. I have seen weak D tests attempted on samples with weakly positive DATs that turned out negative so I assume that could happen with an auto control also. I know the tests are not truly identical but would we ever miss anything significant if we did DATs only?

Probably not Mabel, but working in a Reference environment, we tend to go to the N^th degree with our investigations.

Is there a standard way of performing an auto control ? I have seen an auto with rr panel cells. If someone could explain

Thanks

2 hours ago, Tabbie said:

Is there a standard way of performing an auto control ? I have seen an auto with rr panel cells. If someone could explain

Thanks

An autocontrol is an indirect antiglobulin test that includes both patient serum/plasma and patient rbc incubated together at 37C and subsequently tested with antihuman globulin reagent.  Methodology includes the standard tube test, Gel test, PEG test etc.

When we automated (Echo), we stopped doing autocontrols routinely with panels. It's not even an available test on the Echo. If all screen or panel cells are positive that's a different story. We can run a DAT or crossmatch the patient with their own cells to give us an autocontrol. If we need to move to tube testing to resolve a problem I require the auto control using whatever enhancement media is being used for the panel/screen. If the auto is positive, we do a DAT. If there is suspicion of a hemolytic transfusion reaction or a hemolytic process we would do an auto and/or a DAT. Obviously a reference lab is going to approach things in a different way than a transfusion service.

I think that the sensitivity of the method, gel or solid phase, can be a bit of a curse - you find things that are not meaningful for transfusion purposes by doing autos on everyone. If the antibody is straight forward and there is no evidence or history of hemolysis/WAIHA, does the positive auto give us information of value? We've been doing it this way for almost 8 years now and it hasn't caused any issues, not even once. That positive autocontrol just gives you hornets to chase most of the time and doesn't change how you transfuse the patient. As my boss likes to ask - "Does it add value to the process?" If it doesn't, don't do it.

I thought you needed to do an auto control if using Ortho panel

CONTROL OF ERROR

1. A control consisting of the serum and autologous red blood cells prepared according to the ID-Micro Typing

System package insert should be tested in parallel with 0.8% RESOLVE Panel A. A positive reaction indicates

patient abnormality which must be resolved before the test results can be interpreted.

16 hours ago, tkakin said:

I thought you needed to do an auto control if using Ortho panel

CONTROL OF ERROR

1. A control consisting of the serum and autologous red blood cells prepared according to the ID-Micro Typing

System package insert should be tested in parallel with 0.8% RESOLVE Panel A. A positive reaction indicates

patient abnormality which must be resolved before the test results can be interpreted.

Immucor's Panoscreen and Panocell inserts don't include that requirement. The Panocell insert states "If an autocontrol is to be run in parallel, ...". The Panoscreen insert states "If an autologous control is to be run in parallel,...". The inserts for the solid phase screens and ID panels don't mention autos at all.

If we can resolve the patient's antibody issues with solid phase only, no autocontrol/DAT is performed. If we need to utilize tube testing, an auto is run using whatever enhancement media is used for the tube screen/panel.