L.C.H.

so, to answer some questions folks have asked - this is with a negative DAT on babe (would not consider it if the DAT was positive unless really, really stuck for product) these are usually moms who had their 28 wk dose, but then had either episode of bleeding or motor vehicle accident or other trauma, and got one additional dose (300 micrograms) of RhIg in the third trimester. Or, alternatively, moms who got their 28 wk dose but then delivered well before 40 wks.

We've had to do some finagling in a couple cases (in light of the continuing blood shortage) and are also in the process of reviewing our SOPs, and we are curious about other folks' practices with the following setting: Mom has anti-D due to RhIg at the time of delivery. Baby is Rh-positive and needs product. Our current SOP is that we must give Rh-negative products to the baby, because of the mom's residual RhIg showing. I've had to override this a couple times recently in order to either comply with other maternal antibodies, or to get a young-enough unit on the fly. Am wondering if there is actually any utility in hewing to this in our SOP, since presumably baby's Rh-positive cells are already keeping any residual maternal RhIg tied up. Curious how others handle this scenario!

OK, follow-up as promised with results of the D chip - and I have some reading up to do on these. Overall predicted RhD phenotype: D+ (weak partial) Alleles: - RHD*weak partial 4.0 encodes p.201Arg and p.223Val - Hybrid RHD*D111a-CE(4-7)-D does not encode D but encodes partial C as part of r'S haplotype The report includes a reference: "Experience with RHD*weak D type 4.0 in the USA," Blood Transfusion 2018:6: 1-3.

I also should get up earlier to contribute! thank you all for the suggestions! In response to some of the ideas - her pregnancy loss end of last year and surrounding OB care was entirely through my institution, and I know we didnt give her any RhIg of any sort. Could find no evidence of ITP (handful of CBCs over months have been dead normal), no evidence of any underlying autoimmune disorder. No evidence of getting IVIG or any other antibody-based treatment. The only possible autoimmune trigger I recognized was the strep throat, but that's a long shot and anyhow she was promptly treated. And we don't use gel. Overnight we came up with some of the same ideas as y'all - warm auto with anti-D specificity, an anti-LW, or a D antigen variant. Just hearing from the manager we ran her against some O negative cord cells this morning; does not look like an anti-LW. We are opting to use what is left of the sample to send to reference for the D chip. I'll definitely update once we have more info!

Since PathLabTalk just asked folks to please participate by making a post, I'll offer up our conundrum of the day - we haven't yet done much workup: Young healthy woman had early pregnancy loss last year, she typed twice as O pos, no antibodies, did not get any products. We did not have to do a weak D on her. Now in early pregnancy again; early this month she showed O pos, antibody screen pos, antibody not ID'ed, positive DAT, no lab evidence of lysis. We asked for more tubes but they sent only one, now several weeks later. Again O pos, antibody detected, though decreased in intensity - and now is ID'ed as anti-D Both times the antibody has been stronger than would be expected for RhIg, and anyhow I can find no instance of her having been given RhIg. In Feb she had strep throat but she was treated, so I don't think it is a post-strep autoimmune phenomenon (plus I dont think that usually manifests against RBC antigens?) Anyone seen anything like this? We are going to again ask for more tubes so we can send her to reference center. I will post follow-up as we work this out.

OK i dont really understand this, but i asked for more specifics - and our backup computers are evidently attached to the network but in a weird limited fashion where they get a solitary incoming dump every four hours, of BB data, but otherwise do not receive network activity, and have no "outgoing" channel. when we were hacked, one was due for a dump and got hacked, the other was instantly quarantined off-line and so had almost all (except the last few hours worth) of BB data. also was just told it is also now stashed in some quarantined part of the cloud? this is waaaay over my head in terms of IT though. sorry i cant explain it any better :-(

Our inpatient consents are good for the duration of the admission. Outpatient consents are only good for the one visit, with two exceptions: 1) A onc/chemo pt, where the consent covers the time period of the entire outpatient chemo course 2) A pregnant pt, where the consent covers the entire outpatient portion of the pregnancy (usually chronically anemic women who are not responding to iron and need occasional pRBCs to bump up). That consent doesnt cover the admit for delivery though - that's a separate consent (hello, DIC MTPs!)

We tell our clinicians to do exactly that, yes. Likely it won't turn into an anaphylactic event, but it could, so STOP and initiate a transfusion workup. Give benadryl and watch the patient. For future transfusions, pre-treat with benadryl - even though it's likely a response to that one specific donor's plasma proteins, and a bag from a different donor may not provoke a reaction.

In terms of hacking- we have two offline PCs, one here and one at our sister hospital, that contain backups of BB data for both hospitals (dont know how often we back it up though). we were hit by ransomware last June (downtime for a week in the middle of COVID, yay)and then found out IT had connected one of those two "offlines" to the network, and it was gone. We still had one lonely functioning PC, tho, with the entire systems' BB data, adn it got us through what was otherwise a very, very dicey time.

thanks for all the responses! looks like most folks, like us, have the KBs read in hematology. And the inspector was OK with it; i think he'd just been looking at our BB personnel competency forms, but when he asked for the KB staff competencies he didnt like the (slightly different) format that our heme dept uses. He was a very seasoned inspector, so when he said BB, not heme, most often reads KBs, I just got curious if our institution is really an outlier in that respect. Seems not!! thanks!

Greetings all - We are having an AABB inspection, and a curious question has come up. The inspector is accustomed to KBs being read by blood bank personnel, so any issuance of RhIg (more than the typical vial) is based ona result coming out of blood bank, and acted on by blood bank. However, in our lab, KBs are read by heme, and it's now created some confusion around which lab section 'owns' the competencies. Our heme lab uses a slightly different format for competencies (a problem in and of itself, but not the issue at hand), and the inspector is a bit discomfited by this. I have only worked in two hospitals, and in both, KB was read by heme but actedf on by BB. and this question simply hasnt come up during inspections previously. so as an informal survey, I am just curious - which lab section reads and results your KBs?

we require two types before issuing type-specific blood, and has to be two different samples from two different sticks. we bill for both.

"Interesting topic, we had a 32 bed NICU and I don't remember ever transfusing platelets." we have a larger NICU, but have transfused plts to babies twice already this week, so it's not uncommon from where I sit. we have NAIT babies very frequently, as well as babies that bleed, drop their plts, need to go to surgery, and we bump their platelets first.

If the antibody is no longer present in this pregnancy, then so far, so good! but some antibodies can wax and wane, and if this fetus is positive for an 'offensive' antigen, that antibody may start kicking up again in mom during the pregnancy. If you know which antibody caused it last time, you can look up and see if it is one that tends to wax and wane. Personally, I'd be concerned that the mom you describe could have HDFN again with this current fetus if the fetus has the offending antigen and mom's immune system catches wind of it. I am unclear on the recommendation that titering would only be done with the first pregnancy - our titer levels are what trigger OBs to order Dopplers for fetal anemia, so I don't know how titers could just be passed over simply b/c it's a different pregnancy. We often see the same woman come back across years with multiple pregnancies, and yes, if we find a clinically significant antibody, we do start chasing titers, regardless of whether she has ad the antibody in the past.

We've had this happen also, and in a perfect world I'd prefer the OBs resume titers in a bit (give the RhIg time to wane) to see if anti-D is shooting up. We've been burned twice in the past six months where OBs stopped checking titers and switched to Dopplers, which showed decreased risk of fetal anemia, and the babes came out with peripheral blood full of erythroid precursors - right on down to erythroblasts - requiring emergent exchange. So I personally would request a repeat titer closer to delivery, just so you know what you may be dealing with. I don't trust the Dopplers (sorry, radiology!)