Jump to content

Cold agglutinin procedure


Recommended Posts

Would anyone be willing to share their cold agglutinin titer procedure with me?  I am a relatively new Blood Bank supervisor and, though I have many years of Blood Bank experience, I have no reference lab experience.  The procedure at my new facility hasn't been revised since 1999 and has several glaring issues.  For example, it says to incubate the tubes "overnight."  Is that for 8 hours, 24 hours?  I reviewed the procedure in the Technical Manual and it makes much more sense to me, but I was hoping I could get some examples of what is being done at other facilities.  I would appreciate any information you all are willing to share.  Thanks.

Link to comment
Share on other sites

If you read Petz LD, Garratty G.  Immune Hemolytic Anemias.  2nd edition, 2004, Churchill-Livingstone you will read that they wrote that neither the specificity of the auto-antibody, nor the titre of the antibody makes the slightest bit of difference to how the patient is treated.  The important thing is the thermal amplitude of the antibody.  If the auto-antibody reacts at 30oC, it is clinically significant in terms of cold auto-immune haemolytic anaemia.

George, who I am proud to say I knew quite well, signed my book in 2004, but I didn't catch up with Lawrie until 2015, but neither of them ever told me that they had changed their mind about the above.

Link to comment
Share on other sites

I agree, Malcolm, I believe the titer is not clinically significant, but I haven't yet convinced the ordering physicians of this.  I will save the reference you cited in case I have an opportunity to plead my case.  We don't currently perform thermal amplitude testing at my facility, so we would have to send the specimens to a reference lab if we decide to do them.  Thank you for your input.

Link to comment
Share on other sites

I was in your position a few years back, attempting to update an outdated microbiology procedure, and now follow the procedure from the AABB Technical Manual.  I considered discontinuing this infrequently ordered test and sending the orders to our Reference Lab, however they offered to send comparative samples for PT, which we implemented.  My most recent AABB/CAP assessor was pleased with the process and outcome.

Link to comment
Share on other sites

  • 3 weeks later...
On 6/9/2019 at 6:19 AM, Tympanista said:

Would anyone be willing to share their cold agglutinin titer procedure with me?  I am a relatively new Blood Bank supervisor and, though I have many years of Blood Bank experience, I have no reference lab experience.  The procedure at my new facility hasn't been revised since 1999 and has several glaring issues.  For example, it says to incubate the tubes "overnight."  Is that for 8 hours, 24 hours?  I reviewed the procedure in the Technical Manual and it makes much more sense to me, but I was hoping I could get some examples of what is being done at other facilities.  I would appreciate any information you all are willing to share.  Thanks.

I much rather perform titer and thermal amplitude as outlined in Petz and Garratty's, Immune Hemolytic Anemias textbook. And also, Thermal Amplitude Test with albumin has much higher positive predictive value per Table 5-14 in the textbook. So if the test were to be overhauled, I would perform titer and thermal amplitude, and supplement thermal amplitude testing with album if necessary. 

Edited by Bb_in_the_rain
Link to comment
Share on other sites

10 minutes ago, Bb_in_the_rain said:

I much rather perform titer and thermal amplitude as outlined in Petz and Garratty's, Immune Hemolytic Anemias textbook. And also, Thermal Amplitude Test with albumin has much higher positive predictive value per Table 5-14 in the textbook. So if the test were to be overhauled, I would perform titer and thermal amplitude, and supplement thermal amplitude testing with album if necessary. 

Thank you for the references.  I'm always curious to know what is being done in other labs.  We don't currently perform thermal amplitude testing here, so that may end up being a sendout test.  I've been tracking all of the cold agglutinin titer orders we've gotten over the past few months and they all seem to be coming from one physician who is ordering them as part of an autoimmune panel for patients with Raynaud's.  I will have my Medical Director speak with him after reviewing the reference you provided and we may be able to convince the physician to request thermal amplitude testing along with, or instead of the cold agglutinin titers.

Link to comment
Share on other sites

6 minutes ago, Tympanista said:

Thank you for the references.  I'm always curious to know what is being done in other labs.  We don't currently perform thermal amplitude testing here, so that may end up being a sendout test.  I've been tracking all of the cold agglutinin titer orders we've gotten over the past few months and they all seem to be coming from one physician who is ordering them as part of an autoimmune panel for patients with Raynaud's.  I will have my Medical Director speak with him after reviewing the reference you provided and we may be able to convince the physician to request thermal amplitude testing along with, or instead of the cold agglutinin titers.

It may be more efficient workflow to perform titer at 4 different temperature, 22C, 30C, 37C and read them after 1 hour incubation. That way, you get your titer and thermal amplitude done in one shot and also see the titer difference between your 3 different temperature. Also, your order physician does not have a choice but to perform titer and thermal amplitude as they are offered as one test. 

Edited by Bb_in_the_rain
Link to comment
Share on other sites

22 minutes ago, Bb_in_the_rain said:

I much rather perform titer and thermal amplitude as outlined in Petz and Garratty's, Immune Hemolytic Anemias textbook. And also, Thermal Amplitude Test with albumin has much higher positive predictive value per Table 5-14 in the textbook. So if the test were to be overhauled, I would perform titer and thermal amplitude, and supplement thermal amplitude testing with album if necessary. 

But the titre tells you nothing (it is about as useful as either the specificity or a chocolate tea pot!  See Win N, Needs M, Rahman S, Gold P, Ward S.  An unusual case of an acute haemolytic transfusion reaction caused by auto-anti-I.  Immunohematology 2011; 27 (3): 101-103, amongst others).

We just go with the thermal amplitude, but we do agree that albumin should be included (as per Petz and Garratty, as above).

Link to comment
Share on other sites

4 minutes ago, Malcolm Needs said:

But the titre tells you nothing (it is about as useful as either the specificity or a chocolate tea pot!  See Win N, Needs M, Rahman S, Gold P, Ward S.  An unusual case of an acute haemolytic transfusion reaction caused by auto-anti-I.  Immunohematology 2011; 27 (3): 101-103, amongst others).

We just go with the thermal amplitude, but we do agree that albumin should be included (as per Petz and Garratty, as above).

My goal is to convince the physician that the thermal amplitude is the appropriate test for these patients, but some physicians are resistant to change, even when presented with definitive evidence to the contrary.

Link to comment
Share on other sites

5 minutes ago, Malcolm Needs said:

But the titre tells you nothing (it is about as useful as either the specificity or a chocolate tea pot!  See Win N, Needs M, Rahman S, Gold P, Ward S.  An unusual case of an acute haemolytic transfusion reaction caused by auto-anti-I.  Immunohematology 2011; 27 (3): 101-103, amongst others).

We just go with the thermal amplitude, but we do agree that albumin should be included (as per Petz and Garratty, as above).

I agree with titer value. As the physicians prefer seeing a numerical value, it is hard to turn down an order for titer. I think there were other publication out there eliciting the association of Mycoplasma Pneumonae infection to anti-I titer and Infectious Mono  associated with anti-i titer, etc. it is really really hard to not perform titer when physician comes to the hospital labs with such requests. I rather offer titer and thermal amplitude as one test so that both will be performed. 

Link to comment
Share on other sites

25 minutes ago, Bb_in_the_rain said:

I agree with titer value. As the physicians prefer seeing a numerical value, it is hard to turn down an order for titer. I think there were other publication out there eliciting the association of Mycoplasma Pneumonae infection to anti-I titer and Infectious Mono  associated with anti-i titer, etc. it is really really hard to not perform titer when physician comes to the hospital labs with such requests. I rather offer titer and thermal amplitude as one test so that both will be performed. 

I am not going to be "precious" about this, but what would you tell the physicians if you had a case where there was an antibody of wide thermal amplitude (reacting at, at least 30oC), but had a low titre (given that most cases, but by no means ALL cases of CHAD involve an antibody with a titre above 512)?  In our own case, see above, we found that antibody had a titre of 256 at 4oC, the anti-I had a titre of 16 at 23oC, the anti-i a titre of 4 at 23oC, the anti-I reacted only in neat plasma at 30oC and the anti-i was not detected at 30oC.  On the other hand Professor Sir John Dacie (a nice chap if ever there was one) stated that, in general, naturally occurring cold-reactive auto-antibodies have a titre below 64 at 4oC and have a thermal amplitude of less than 20oC (Dacie J V.  The haemolytic anaemias, congenital and acquired, part II.  The auto-immune haemolytic anaemias.  2nd edition, 1962, Churchill, London, 460), whereas Petz and Garratty. world experts in auto-immune disease, both of whom have been given numerous awards throughout the world, state, "In general, anti-I is commonly found in patients with CHD, and the auto-antibody titre is much higher (>1, 000) at 4oC (Petz LD, Garratty G.  Immune Hemolytic Anemias.  2nd edition, 2004, Churchill-Livingstone).

I agree though, it is incredibly difficult to change the minds of clinicians who have bee told dubious "facts" during their education, however famous are the references.

Link to comment
Share on other sites

3 hours ago, Malcolm Needs said:

I am not going to be "precious" about this, but what would you tell the physicians if you had a case where there was an antibody of wide thermal amplitude (reacting at, at least 30oC), but had a low titre (given that most cases, but by no means ALL cases of CHAD involve an antibody with a titre above 512)?  In our own case, see above, we found that antibody had a titre of 256 at 4oC, the anti-I had a titre of 16 at 23oC, the anti-i a titre of 4 at 23oC, the anti-I reacted only in neat plasma at 30oC and the anti-i was not detected at 30oC.  On the other hand Professor Sir John Dacie (a nice chap if ever there was one) stated that, in general, naturally occurring cold-reactive auto-antibodies have a titre below 64 at 4oC and have a thermal amplitude of less than 20oC (Dacie J V.  The haemolytic anaemias, congenital and acquired, part II.  The auto-immune haemolytic anaemias.  2nd edition, 1962, Churchill, London, 460), whereas Petz and Garratty. world experts in auto-immune disease, both of whom have been given numerous awards throughout the world, state, "In general, anti-I is commonly found in patients with CHD, and the auto-antibody titre is much higher (>1, 000) at 4oC (Petz LD, Garratty G.  Immune Hemolytic Anemias.  2nd edition, 2004, Churchill-Livingstone).

I agree though, it is incredibly difficult to change the minds of clinicians who have bee told dubious "facts" during their education, however famous are the references.

 If we see cases of CAD with titer <64 that is reactive at 30C with or without albumin, that would be a perfect opportunity to start a conversation with reference to Garratty G et al, The correlation of cold agglutinin titrations in saline and albumin with haemolytic anemia, BrJ Haemat 1977;35, along with the paper that you have cited above (which I am printing out and filing it in my "good hemolytic anemia reference" folder now) B)

 

Link to comment
Share on other sites

3 minutes ago, Bb_in_the_rain said:

 If we see cases of CAD with titer <64 that is reactive at 30C with or without albumin, that would be a perfect opportunity to start a conversation with ordering physician with references to Garratty G et al, The correlation of cold agglutinin titrations in saline and albumin with haemolytic anemia, BrJ Haemat 1977;35, along with the paper that you have cited above (which I am printing out and filing it in my "good hemolytic anemia reference" folder now) B)

 

 

Link to comment
Share on other sites

  • 3 weeks later...

The technical manual says to prepare the serial dilutions up to 1:4096.  Does anyone take their dilutions out further?  Our LIS is currently set up to report up to > 8192, but is there really any clinical significance to reporting a value greater than 4096?

Link to comment
Share on other sites

30 minutes ago, Tympanista said:

The technical manual says to prepare the serial dilutions up to 1:4096.  Does anyone take their dilutions out further?  Our LIS is currently set up to report up to > 8192, but is there really any clinical significance to reporting a value greater than 4096?

There is no clinical significance to reporting ANY titre in the case of a "cold-reacting" auto-antibody, despite what the technical manual may say.  See, for example, Win N, Needs M, Rahman S, Gold P, Ward S.  An unusual case of an acute haemolytic transfusion reaction caused by auto-anti-I.  Immunohematology 2011; 27 (3): 101-103, but, MUCH more importantly, see Petz LD, Garratty G.  Immune Hemolytic Anemias.  2nd edition, 2004, Churchill-Livingstone.

Low titre "cold reacting" auto-antibodies can be clinically significant, but the measurement of paramount importance is the thermal amplitude.  If the antibody reacts at 30oC, it is clinically significant whatever its titre and whatever its specificity.

Link to comment
Share on other sites

20 minutes ago, Malcolm Needs said:

There is no clinical significance to reporting ANY titre in the case of a "cold-reacting" auto-antibody, despite what the technical manual may say.  See, for example, Win N, Needs M, Rahman S, Gold P, Ward S.  An unusual case of an acute haemolytic transfusion reaction caused by auto-anti-I.  Immunohematology 2011; 27 (3): 101-103, but, MUCH more importantly, see Petz LD, Garratty G.  Immune Hemolytic Anemias.  2nd edition, 2004, Churchill-Livingstone.

Low titre "cold reacting" auto-antibodies can be clinically significant, but the measurement of paramount importance is the thermal amplitude.  If the antibody reacts at 30oC, it is clinically significant whatever its titre and whatever its specificity.

Do you report a titer for the thermal amplitude or just the temperature of reactivity?

Link to comment
Share on other sites

My understanding and experience of thermal amplitude testing is to identify a cold autoantibody and determine if it is clinically significant or primarily just a nuisance. I have never been involved in cold autoantibody titers; can someone explain its purpose please.  

Link to comment
Share on other sites

At my facility we perform a mini cold panel and if positive (1+) reaction at 4C it is sent to reference for an cold antibody titer. I do not have a test code built in the computer to  capture this process.  Can someone share a procedure how one enters their cold antibody workup  and titers into the computer system?

My reference lab at this time is no longer performing cold antibody titers. I have one physician who routinely orders cold antibody titers. IF I implement titers testing then we would have to PT on this assay.

Link to comment
Share on other sites

1 hour ago, ESIZENSKY said:

At my facility we perform a mini cold panel and if positive (1+) reaction at 4C it is sent to reference for an cold antibody titer. I do not have a test code built in the computer to  capture this process.  Can someone share a procedure how one enters their cold antibody workup  and titers into the computer system?

My reference lab at this time is no longer performing cold antibody titers. I have one physician who routinely orders cold antibody titers. IF I implement titers testing then we would have to PT on this assay.

I bet your Reference Laboratory are laughing out loud at being asked to perform cold antibody titres with a 1+ reaction at 4oC.  I know I would if we weren't so busy doing proper tests and were PAID to perform these totally irrelevant tests.

Could you not persuade that one physician who routinely orders cold autoantibody titres to have a word with all of his or her fellow physicians and ask them how on Earth they manage to 1) keep their patients alive, and 2) possibly even cure them without knowing what this single physician deems to be vital information?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    • No registered users viewing this page.
  • Advertisement

×
×
  • Create New...

Important Information

We have placed cookies on your device to help make this website better. You can adjust your cookie settings, otherwise we'll assume you're okay to continue.