I'm wondering if anyone has ever seen or knows of an antibody which does not react with cells that are positive for K, Kpa, or Jsa, but seems to react weakly with all other cells (w-1+ with PEG)? Perhaps it is just a coincidence that the non reacting cells had these particular characteristics, but it did catch my attention!

I've had several years experience in a reference laboratory but don't recall ever encountering anything that fits this description. My guess would be that it was just a fluke. Does this antibody also react in LISS and albumin? PEG is notorious for weak scratchy reactions that mean nothing.

I hate PEG....alot of Anti-Junk.....especially b/c of the scratchy rx's people tend to over read!!

I think PeG definitely has its place. I wouldn't use it routinely and do not let my techs use it unless it seems prudent. However, I have seen those weak, junky reactions in LISS become C's and Kidds in PeG.

Hi Claudia! I think it's interesting that your antibody doesn't react with cells that are positive for the low incidence antigens in the Kell system. I have to wonder if it is Kell system related....I would try testing some DTT-treated or EGA-treated cells. Since the reactivity is so weak, I wonder if the antibody is directed toward a high-incidence antigen in the Kell system and the presence of K, Jsa or Kpa affects the antigen expression of the HIA.

As an aside, I think PEG is a great reagent and much of the "scratchy junky" reactions people are describing actually turn out to be identifiable in a Reference Lab setting. We see no more "extraneous" reactions in PEG than we do in any other media.

I agree with Nancy. With the exception of non-reactivity with the Js(a+) cells, it sounds like an anti-k that is not reacting with single dose K+k+ cells or Kp(a+)k+w cells. The presence of the Kpa antigen can weaken the expression of the k antigen. Some panel manufacturer's mark this on their antigrams, others don't. Try typing your patient for k antigen.