Hi ,

First of all I want to say that the members of this site are wonderful: I have learned so many things from yours posts. This is really the best forum of immunohematology on internet.

I’d like to ask your help for a case.

I have 2 patients, 2 brothers with the suspect of McLeod’s Syndrome on the basis of their neurologic symptoms . The neurologist ask to me the study of Kell antigens.

They are both:

K- k(cellano) +

Kpa- Kpb +

IAT: negative

The serologic reaction of k( cellano) are 4+ with Immucor’s microplate technology and the serologic reaction of kpb are 3-4 + on Diamed’s column agglutination

As I have read on this site, I perform a titration of kell antisera with patient’s cells and with blood donor’s cells. The patient’s titres are the same of the blood donor’s ones.

On this basis, can I say that the probability of McLeod phenotype is not very high, also if I’m not able to demonstrate the absence of Kx? :confused:

I’m sorry for my English and thanks in advance for any help

Hi ,

First of all I want to say that the members of this site are wonderful: I have learned so many things from yours posts. This is really the best forum of immunohematology on internet.

I’d like to ask your help for a case.

I have 2 patients, 2 brothers with the suspect of McLeod’s Syndrome on the basis of their neurologic symptoms . The neurologist ask to me the study of Kell antigens.

They are both:

K- k(cellano) +

Kpa- Kpb +

IAT: negative

The serologic reaction of k( cellano) are 4+ with Immucor’s microplate technology and the serologic reaction of kpb are 3-4 + on Diamed’s column agglutination

As I have read on this site, I perform a titration of kell antisera with patient’s cells and with blood donor’s cells. The patient’s titres are the same of the blood donor’s ones.

On this basis, can I say that the probability of McLeod phenotype is not very high, also if I’m not able to demonstrate the absence of Kx? :confused:

I’m sorry for my English and thanks in advance for any help

Well, first of all madeleine, you should not apologise for your English - it is better than mine and I've lived here all my life!!!!!!!!!!!! I think, from what you are saying (reactions as strong as the controls and titre the same as the control cells) I would say without doubt that the probability of a McLeod phenotype is extremely low. Although it is sometimes difficult to see the antigen weakening with the potent monoclonal reagents that we use these days, you should be able to see the weakened antigens with a titration - and you cannot. Is the reason that you cannot demonstrate the absence of Kx only because you have no anti-Kx available? If so, I'm not surprised, as it is a very rare antibody.

Effectively I am not able to demonstrate the absence of Kx because I haven’t Kx antibody and also in molecular testing in our BB we haven’t the specific primers for it (really I am not sure there are primers commercially available for Kx ).

Thanks a lot for your help, Malcolm!!!!!!!!!!

:):):):):):):):):):):)

I found a McLeod donor last year when I was randomly screening donors for Kpb. In tubes, I wasn't able to pick up K, Kpa, or Kpb. Tube testing of k was only microscopically positive. With as strong of reactions as you're getting, I wouldn't think your patient has the McLeod phenotype.
 

Edit: Also, you may want to check out a blood smear on your patient. McLeod phenotype results in acanthocytes due to membrane structural changes from the missing Kx antigen. That may help give you another clue. That was one thing I noticed when I was reading my tubes microscopically, not a single red cell looked normal under the scope.

Edited May 20, 201312 yr by Emwilson7