My question about in gel card method if both rouleaux and cold autoantibodies can give extra reactions in forward and reverse grouping how can differentiate between theses 2 conditions ?

Cold auto antibodies can give you false positives in the forward group - but will also give you a false positive in the control well, so this will be picked up.  The reverse group will also be positive.  

I have yet to see a case of  'normal' rouleaux that is so heavy that it will do this, but it is possible if bloods are taken directly after administration of plasma expanders.

 

16 minutes ago, galvania said:

Cold auto antibodies can give you false positives in the forward group - but will also give you a false positive in the control well, so this will be picked up.  The reverse group will also be positive.  

I have yet to see a case of  'normal' rouleaux that is so heavy that it will do this, but it is possible if bloods are taken directly after administration of plasma expanders.

Thanks but i mean if i see false positive in forward , reverse and autocontrol is it cold auto or rouleaux?

You will not know just on the basis of this single test.  Looking under the microscope can help (not at the card!) to see if rouleaux is present.  The diagnosis can also help.  Also  a cold auto-antibody will disappear if the test is carried out strictly at 37°C; the rouleaux will not.

8 hours ago, galvania said:

You will not know just on the basis of this single test.  Looking under the microscope can help (not at the card!) to see if rouleaux is present.  The diagnosis can also help.  Also  a cold auto-antibody will disappear if the test is carried out strictly at 37°C; the rouleaux will not

Thanks alot

In what situations would you use a saline replacement technique if the apparent reactivity is suspected to be only rouleaux?

Reverse ABO typing, and IS crossmatch.

Scott