JoJo Smith

Our ARC IRL implemented Gel testing years ago when our hospitals did, so we could see what they were seeing. It was a big learning curve. We found that warm autoantibodies and antibodies towards antigens in the CH/RG, Knops, and COST systems do not react the same in Gel as they do by tube. In Gel, both types of antibodies can be 2+ with a few cells and negative with others. This is neither textbook reactivity nor reactivity experienced staff have seen in tube for these specificities. When we first implemented Gel, hours were spent trying to identify the antibodies. Once this type of serology was observed in many patients and was proved either a warm autoantibody or an antibody in the CH/RG, Knops, or COST system, we stopped using Gel when the patient's DAT was positive. Our primary method is a Peg-IgG panel for any submitted sample, and if it is negative, we set up a Gel panel to see what the hospital saw. If alloantibodies are ruled out and the antibody has 'no apparent specificity', we do not try to categorize which specificity (CH/RG, Knops, COST) the patient has, which provides an answer quickly to the hospital. Both Peg-IgG tube and Gel are fine tests for routine antibody detection and identification until the patient has a warm autoantibody or antibodies to antigens in the CH/RG, Knops, and COST systems (often the reason samples are sent to an IRL), then in our experience, a Peg-IgG method is better.