83 y.o. B pos male transfused 8 units 4 mo. ago. In now for another orthopedic surgery. Screen pos in both cells by Ortho gel—2+ with K+, Fya+ hetero, Jka+ (homoz) & W+ with K-, Fya+ hetero, Jka-. Gel panel looked like anti-K (2+) and anti-Jka (varies from neg with one hetero cell and w+ with one homoz cell to 2+ with 1 hetero and also with 1 homoz cell—all of these K & Fya neg). Couldn’t rule out Fya so ran more cells and detected anti-Fya reacting neg (one cell) to 2+ with hetero and 2+ with 1 homoz (all Jka neg, K neg cells). Thus it looked pretty clearly like anti-K, Fya and Jka even though it missed reacting with a hetero cell of each of the latter two and the reaction strength was pretty variable with the Jka cells. It does not react with any cells that are not positive for one or more of these 3 antigens. We have 5 reagent cells that are not reacting. The patient has a gel auto control that is 1-2+ but a DAT that is microscopically positive with IgG (and neg for complement). He types as neg for the K antigen. We use a room temp anti-Jka and his cells type 3+ with that. Although our anti-Fya is AHG we antigen typed him for Fya (since his DAT was only micro positive) and got a 3+. Controls all worked; right antisera used; tests repeated the same. So we did an elution which tests negative with screen cells by modified tube method and 3-4+ by gel with all 13 cells tested including the 5 that were negative with the plasma.We also crossmatched 2 B+ K- units and they are both compatible by gel and by saline tube AHG (but they are both positive for both Jka & Fya). We did a 3 cell PEG screen on the plasma which reacted with the K+, Fya+, Jka- cell and the homoz Jka+ cell but not the hetero Jka+ cell.Patient has not been given IVIG or transfused recently. He has not received any plasma or any other source of passive antibodies.So, is this a weak warm auto with a mimicking specificity of both anti-Fya and anti-Jka? (I count the anti-K as an allo since the patient is K neg.) Why is the eluate neg by the modified tube method? Low avidity so it washes off? Or are we picking up junk in the gel eluate (the reactions look pretty normal—a few more free cells in the bottom than would be expected in a 3-4+, but otherwise normal). I wouldn’t expect an eluate to have antibody to gel diluent and I wouldn’t have expected nice negative results in gel with the plasma if the patient had an antibody to the gel diluent.All suggestions welcome!

Im wondering if gel is over sensitive and picking up a weak weak WAA. How strong was the Auto Control in PEG? PEG will also enhance those WAAs. We do not test eluates in Gel and have seen numerous gel eluates be falsely positive. These weak warm autos in Gel can be a pain. Since the auto control is just as strong as your supposed Kell I still even question that. But in only four months it's possible a true anti Kell would not yet react stronger. Do you have enough patient red cells to do an auto adsorption? Since his last tx is past the three month mark I'm thinking all that weak reactivity would go away. Especially since he types positive for tWo of those antigens. I suppose dual Mimicking WAAs could occur but I have yet to see both a Kidd and Duffy mimicking WAA together. Adsorbing would be the way to find out. The fact that the donor units were comp and positive for those antigens makes me think these are not true allos you're dealing with. Auto antibodies will do what they want to with no rhyme or reason

Edited April 12, 201213 yr by Gnapplec

I agree with Gnapplec that an auto-adsorption is the way to go.

Orthopaedic patients, in particular, often seem to have "junk" reactions, presumably to do with low level infection in the area of the bone that requires surgery??????????

We often see a warm (and sometimes even cold!) auto in gel - splotchy reaction patterns - that do not necessarily show up in tube. Gel CAN be more sensitive than you want. It is not at all unusual for us to see a pos DAT (or auto control) in gel, and have it be negative in tube (IgG).

Just one comment regarding the Jka reactions in GEL. This is something I discovered some years ago when first working with GEL; and found many of our clients sending to us when I was a reference lab supervisor.

In GEL, you can have (not uncommonly), Jka that is non-reactive with Jka heterozygous cells; and only reacts with some homozygous cells. The fist time I saw that, the panel did not fit a pattern and everything had been ruled out on homozygous cells. So I looked to see what the positive cells had in common; only that they were all Jka homozygous. So typed patient; they were Jka NEG. PeG Panel brought the Jka up beautifully. Have run into many of these since.

And this is a long-shot; but just checking to make sure you confirmed that they patient had not been transfused anywhere else since 4 mos. ago when you last saw him (as far as phenotyping)?

Sorry, have nothing else to "add."

Brenda Hutson

Blood can be transfused safely as the crossmatch is compatible and patient also having Fya and Jka antigens.Regarding elution negative result may be the low level of antibodies or may be denatured during elution process.

Just one comment regarding the Jka reactions in GEL. This is something I discovered some years ago when first working with GEL; and found many of our clients sending to us when I was a reference lab supervisor.

In GEL, you can have (not uncommonly), Jka that is non-reactive with Jka heterozygous cells; and only reacts with some homozygous cells. The fist time I saw that, the panel did not fit a pattern and everything had been ruled out on homozygous cells. So I looked to see what the positive cells had in common; only that they were all Jka homozygous." Brenda Hutson

I have seen this reactivity with Jka in solid phase (Capture) as well.