Liz0316

I agree with David and Malcolm, that all antibodies have a specificty, we just don't always know what it is. I use the phrase "all common clinically significant antibodies ruled out." And of course if the antibody screen is positive, regardless of the cause, an AHG XM is used.
Liz

We are developing a protocol, where by we get a baseline sample on the patient, have molecular genotyping done and once the drug is started, we will be testing with DTT and issuing K- red cells. I'll keep watch on the thread and try to keep up with our progress on the protocol.
Liz
 

We do a cord eval work up (ABO/Rh and DAT) on infants born to Rh neg, group O  mothers and mother's with clinically significant antibodies. We hold all cord for 14 days and determine ID my MR number if needed, which doesn't change. The DAT is only done within 24 or 48 hours.... I'm home and don't recall at the moment!
Liz

we don't do any daily checks
weekly - clean and check volume delivered
quarterly - timer check
semi annual RPM check
annual - functional operation - check buttons, reactivity and confirm validity with check cells
annual - change tubing and tube holder inserts
Liz
 

We are a 4-hospital system with the same HIS but 3 of the 4 hospitals have different MRN's and all hospitals issue their own encounter # for each visit.
We do have a unique blood bank identifier # that prints on the patient's armband that is the same across facilities and across visits.
However, each time a patient is transferred to a different facility, we require that the receiving facility get a new type and screen specimen. The only time this is not true is for preadmit/pre-surgical patients. If a patient wants to have their blood drawn at a sister hospital because it's closer to their home, they can do so, but the specimen is collected and labeled with a handwritten label and the order is a paper requisition. Both of these items are delivered to the facility where the patient will have their surgery, a new encounter is registered, the type and screen ordered and the testing performed. The specimen remains at the testing facility where the patient is having surgery.

We perform fetal screens (rosette test) following obstetrical events on Rh negative women at 16 weeks or greater.  In the past, the literature has discussed 20 weeks as the " magical number," so, to error on the side of caution, we perform at 16 weeks.  The Kliehauer Betke is used for a variety of reasons, but if the clinician wants to give RhIg following an event that may cause a bleed - amnio, car accident, miss abort, etc... That is our number. Under 16 weeks we just supply the product after confirmation of Rh neg blood type of the mother.

I agree, pre warm, done correctly, should be done by a tube method. GEL will only enhance some colds. I think the pre warming of plasma and reagents with a warm wash phase will give the best results.

I agree, pre warm, done correctly, should be done by a tube method. GEL will only enhance some colds. I think the pre warming of plasma and reagents with a warm wash phase will give the best results.

I don't believe you can perform a strict prewarmed in gel due to the 10 minutes centrifugation cycle.  I always do prewarmed in tubes.

This is one technique that I would not want to validate in gel.   Gel will enhance reactions and will pick up strong, direct agglutinins.  A microscopic reaction (negative) in tube could be a 1-2+ (positive) in gel.   I don't want to take the chance of enhancing unwanted reactions and would opt tube testing in this case.  I am interested if others have done this and their success or failure.  

really?! well that changes things. Can't wait to discuss this with my inspector this year. I would love to eliminate just one thing!
Liz
 

I've ordered the DTT from Bio-Rad.
catalog # 161-0611 - from the Life Sciences division . 1-800-879-2289
LSG.ORDERS.US@BIO-RAD.COM
I hope that helps.
Liz
 

I've ordered the DTT from Bio-Rad.
catalog # 161-0611 - from the Life Sciences division . 1-800-879-2289
LSG.ORDERS.US@BIO-RAD.COM
I hope that helps.
Liz
 

We use a saline method where by we use 4 drops of plasma to one drop cells, to super-saturate the cell. Incubate 30- 60 min and use IgG at coombs.
This method has served us well in patients with warm autos. Malcom, of course, went into detail about strong bonds and titers, etc., but I tell my techs that "any self respecting allo- antibody will be detected by this method" -
and yes, I'm old school. So it was, back then, once you have discovered there is a problem, or you have actually detected an antibody, going back  to a saline method is a fine and accepted way to get around the garbage you may be detecting in GEL or other "enhancing" method.
Liz
 

We use a saline method where by we use 4 drops of plasma to one drop cells, to super-saturate the cell. Incubate 30- 60 min and use IgG at coombs.
This method has served us well in patients with warm autos. Malcom, of course, went into detail about strong bonds and titers, etc., but I tell my techs that "any self respecting allo- antibody will be detected by this method" -
and yes, I'm old school. So it was, back then, once you have discovered there is a problem, or you have actually detected an antibody, going back  to a saline method is a fine and accepted way to get around the garbage you may be detecting in GEL or other "enhancing" method.
Liz
 

We use a saline method where by we use 4 drops of plasma to one drop cells, to super-saturate the cell. Incubate 30- 60 min and use IgG at coombs.
This method has served us well in patients with warm autos. Malcom, of course, went into detail about strong bonds and titers, etc., but I tell my techs that "any self respecting allo- antibody will be detected by this method" -
and yes, I'm old school. So it was, back then, once you have discovered there is a problem, or you have actually detected an antibody, going back  to a saline method is a fine and accepted way to get around the garbage you may be detecting in GEL or other "enhancing" method.
Liz
 

We use a saline method where by we use 4 drops of plasma to one drop cells, to super-saturate the cell. Incubate 30- 60 min and use IgG at coombs.
This method has served us well in patients with warm autos. Malcom, of course, went into detail about strong bonds and titers, etc., but I tell my techs that "any self respecting allo- antibody will be detected by this method" -
and yes, I'm old school. So it was, back then, once you have discovered there is a problem, or you have actually detected an antibody, going back  to a saline method is a fine and accepted way to get around the garbage you may be detecting in GEL or other "enhancing" method.
Liz
 

We use a saline method where by we use 4 drops of plasma to one drop cells, to super-saturate the cell. Incubate 30- 60 min and use IgG at coombs.
This method has served us well in patients with warm autos. Malcom, of course, went into detail about strong bonds and titers, etc., but I tell my techs that "any self respecting allo- antibody will be detected by this method" -
and yes, I'm old school. So it was, back then, once you have discovered there is a problem, or you have actually detected an antibody, going back  to a saline method is a fine and accepted way to get around the garbage you may be detecting in GEL or other "enhancing" method.
Liz
 

We use a saline method where by we use 4 drops of plasma to one drop cells, to super-saturate the cell. Incubate 30- 60 min and use IgG at coombs.
This method has served us well in patients with warm autos. Malcom, of course, went into detail about strong bonds and titers, etc., but I tell my techs that "any self respecting allo- antibody will be detected by this method" -
and yes, I'm old school. So it was, back then, once you have discovered there is a problem, or you have actually detected an antibody, going back  to a saline method is a fine and accepted way to get around the garbage you may be detecting in GEL or other "enhancing" method.
Liz
 

We use the LISS tube IAT daily in my Reference Laboratory, and, in the right hands (i.e. those who are trained to competency, and are able to demonstrate continued competency, in the technique - which, before the advent of PEG, CAT and solid phase, used to be everyone!), it is perfectly safe.  As I have said before on this site, at one stage that was all we had, and the cemeteries were not full of people who had died of transfusion reactions!
In most cases, not all by any means, but in most cases, although the avidity of the auto-antibody is strong, the titre is not that high, whereas most, not all by any means, alloantibodies that are clinically significant, have a higher titre, even if their avidity is not much to write home about.
The technique is even more useful in cases of a cold AIHA, where the cold auto-antibody tends to have a wide thermal amplitude, but rarely can be detected by tube IAT at 37oC, but, of course, clinically significant alloantibodies will be reactive at 37oC.
Of course, in one way, this technique is safer than using alloadsorbed plasma.  There is no way that alloadsorption red cells would be negative for even one high prevalence antigen (such as Vel, Jra, Ata, etc), let alone negative for multiple high prevalence antigens, and so, if the patient happens to have an antibody directed against a high prevalence antigen underlying the auto-antibody, then the antibody directed against the high prevalence antigen will be adsorbed out, just as the auto-antibody will be adsorbed out, and, hey presto, you have a compatible cross-match, and a patient with (hopefully no more than) a delayed haemolytic transfusion reaction.

If I were you - stop buying the Lewis antisera, dump the N. I do keep M because of the L&D patients. A close large academic hospital is near by and the patients are "shared." Implement the new AABB transfusion guidelines. I'm 2 hours from the blood center, so wasting 7 platelets a month is ok for me. I haven't changed any reagents yet, but since we do dispense albumin from the BB (ick), I have a new vendor with better prices.
Good luck. Tell administration what I tell them, "we may be expensive, but we are cute."...maybe it will work for you!

If I were you - stop buying the Lewis antisera, dump the N. I do keep M because of the L&D patients. A close large academic hospital is near by and the patients are "shared." Implement the new AABB transfusion guidelines. I'm 2 hours from the blood center, so wasting 7 platelets a month is ok for me. I haven't changed any reagents yet, but since we do dispense albumin from the BB (ick), I have a new vendor with better prices.
Good luck. Tell administration what I tell them, "we may be expensive, but we are cute."...maybe it will work for you!

I run my eluates in gel.  99% of the time they are either all positive or all negative.  Occasionally I do get specificity and that is when I expect it (delayed TrxN or the CAP survey).  Are your eluate pos/tube neg rxs 2+ or less?  I have found that 2+ rx in gel are invariably negative in the tube. If your last washes are negative I don't see how what you are finding is technique related.  I just go with the eluate when the tube turns blue - as do my techs who do eluates.  I don't have to know what the pH is because the procedure defines the blue color as the end point.  If you added too much of the buffering reagent I would expect you would get a negative rx - either due to dilution or radical change in pH causing loss of ab reactivity. 
 
What elution kit are you using?  I use Immucor's though I did try HemoBioscience's and found it satisfactory.

Hi lab217,
 
First of all, thank you so much for your very kind words.
 
I am now happy that the antibodies are truly auto-antibodies, given both the lady's Rh phenotype and her ethnic origin, and I would agree with your Reference Laboratory that serial titrations during the pregnancy are not required.  The rational for saying this is in Petz LD, Garratty G.  Immune Hemolytic Anemias.  2nd edition, 2004, Churchill Livingstone, Chapter 9, pages 346-347.  Here, you will find reference to the fact that foetuses can be fatally affected in a pregnancy involving autoimmune haemolytic anaemia, BUT (and this is the important bit) these fatalities are due to the maternal Haemoglobin levels dropping to <60gL-1, and so there is a lack of oxygen transfer to the foetal red cells, rather than the auto-antibody causing a haemolytic crisis in the foetus.
 
When the maternal haemoglobin levels are controlled (by steroids, transfusions, etc, so that sufficient oxygen was getting to the foetal red cells) there was little, if any, evidence of a clinically significant episode of haemolytic disease of the foetus and newborn, beyond the fact that some babies had a positive direct antiglobulin test.
 
Turning to the two alloantibodies I mentioned.  Anti-Ce (also known as anti-Rh7 and anti-rhi - just to confuse matters!!!!!!!!) is a compound antibody that will only react with red cells expressing both the C and e antigens that have been encoded in the same haplotype (rather like anti-ce/anti-f, that will react with rr red cells [RHc and RHe genes in the cis position], but not with R1R2 red cells [RHc and RHe genes in the trans position]).  So, basically what I am saying is that, if a foetus has the phenotype of D+ C+ c+ E+ e+, if the baby's genotype is DCe/DcE, there is a chance that an anti-Ce could affect the baby, whereas, if the baby's genotype is DCE/dce, the baby will not be affected by a maternal anti-Ce.
 
The good news is that anti-Ce is usually only associated with very mild HDFN.
 
Anti-hrB (anti-Rh31) is an antibody that can be produced by individuals who have a variant of the e antigen (a variant that is, to all intents and purposes, only seen within the Black populations - hence the fact that I am comforted by the fact that your pregnant lady is Caucasian).  Anti-hrB mimics a mixture of anti-C and anti-e, with the anti-C-like element often showing as a stronger antibody than the anti-e-like element.  Again, anti-hrB is not usually associated with clinically significant HDFN.  However, there is another Rh antibody, again, normally only found in an individual from the Black populations, anti-HrB (anti-Rh34) that, when weak, or just developing, can mimic an anti-hrB.  Again, anti-HrB is usually associated with mild HDFN, although somewhere in the back of my mind, I seem to recall one case where the baby was severely affected, and required several transfusions (with washed and irradiated maternal blood, which was of the "wrong" ABO type, but the baby survived).  If I am correct, and I can find the reference, I will post this for you.
 
Anyway, I hope this post has served to help you in some way, rather than to confuse the issue further!
 
       

None whatsoever, as long as you are absolutely certain that the antibodies are auto-anti-C and auto anti-e, and not an allo-anti-Ce, or worse, an allo-anti-hrB that is mimicking an auto-anti-C+e.
 
May I be impertinent enough to ask the lady's ethnic background?