Titers for ABO incomp organ transplants

[bmarotto]

I am reposting this here as I think "Other Topics" may not have been the best place for it.

Our transplant team is requesting anti-A and/or anti-B titers for possible ABO incompatible living donor transplants (both kidney and liver). They are also requesting A1 typing if the proposed donor is Group A. It is not clear if they are rejecting an A1 donor or waiting to see what the anti-A titer is. My questions are:

1. What method should be used for the titer? My understanding is they want an AHG titer.

2. For a group A donor, should the cells used to titer the recipient's anti-A be A1 positive, A1 negative, or should we decide based on the A1 status of the donor?

Any help would be appreciated.

[noelrbrown]

Hi, CAP have a program to assess competency in this area, it is the ABT program (antibody titer)

it involves an A1 cell and performing titers using AHG test and Immediate spin. You can get an idea of the immune titer by using DTT to break up the IgM antibody and then titering out the immune Antibody using A1 cells in an AHG test. I understand this is aimed at assessing suitability of A2 kidneys for group B recipients.

[bmarotto]

We do subscribe to CAP ABT and use the uniform tube procedure and read at both room temp and 37/IgG. I was wondering in the case of an A1 negative donor if sites were still using A1 cells or using A1 negative cells. To be conservative, I would imagine using the stronger A1 cells would be the thing to do.

[Malcolm Needs ☆]

The following reference may be of help (or, of course, may not!):

Bryan CF, Winklhofer FT, Murillo D, Ross G, Nelson PW, Shield III CF, Warady BA. Improving access to kidney transplantation without decreasing graft survival: long-term outcomes of blood group A2/A2B deceased donor kidneys in B recipients. Transplantation 2005; 80: 75-80.

[bmarotto]

I found this more recent article from Johns Hopkins:

Montgomery, R. A. et al. ABO incompatible renal transplantation: a paradigm ready for broad implementation. Transplantation 87, 1246–1255 (2009)

They did not give details of the method other to say it was a standard tube isohemagglutinin titer carried through to the antiglobulin phase. There was only one titer result so I assume they did not read a room temp incubation.

[Malcolm Needs ☆]

I found this more recent article from Johns Hopkins:

Montgomery, R. A. et al. ABO incompatible renal transplantation: a paradigm ready for broad implementation. Transplantation 87, 1246–1255 (2009)

They did not give details of the method other to say it was a standard tube isohemagglutinin titer carried through to the antiglobulin phase. There was only one titer result so I assume they did not read a room temp incubation.

I'm certain this article would be far more up-to-date than the one I suggested.

:D