Our reference laboratory occasionally notices very weak, apparently non-specific Coombs reactivity with an antibody screen which seems to have some association with a reactive RPR (negative MHATP). I recently managed to get a copy of a few pages from the latest edition of Petz & Garratty's "Immune Hemolytic Anemias" which describes a report of anticardiolipin antibodies in 22% of SLE patients. The presence of these antibodies caused both positive direct and indirect Coombs tests. We have also noted that some of these RPR-reactive patients have unexplained weakly-positive DATS.

As far as we know none of the patients that we have seen demonstrate this phenomenon have SLE, but we are rarely privy to this type of information. I was wondering if anyone else has seen anything similar to this. Look forward to your comments.

Yes, and I'm sorry this is only anecdotal, we had a woman who was pregnant and had a 1:16 RPR titer, a negative MHA-TP, a strongly positive DAT with no specificity and we never got an answer about her diagnosis.

I thought MHA-TP has not been on the market in the US since 99 or so, and replaced to TP.PA.

If you can obtain MHA-TP in the US, please let me know.

Best Regards,

Harry

My miscue Harry! The specimens which we are encountering are all RPR-Reactive, TP PA negative. I guess this illustrates that I'm a bit behind the times. Thanks!