Low titer A plasma in three AB patients for therapeutic plasma exchange

Abstract

Background Currently, low titer A plasma is used on a routine basis in bleeding trauma patients of unknown AB type. Three AB non‐bleeding apheresis patients are presented here who safely received a combination of AB and low titer A plasma during therapeutic plasma exchange (TPE). One control AB patient received AB plasma only. Methods Data was obtained retrospectively on number of procedures, volume replaced, total plasma, and A plasma volumes including hemolysis laboratory data. Average A plasma volume and % of A plasma out of total plasma volume used were calculated. Results Two female AB patients were treated for thrombotic thrombocytopenic purpura (TTP) with TPE and a third female AB patient was treated for microangiopathic hemolytic anemia. Patient 1 received a total of 12 procedures, 10/12 with AB+A plasma (average 916.3 ±84.6 mL). Patient 2 received a total of 12 procedures, 4/12 with AB+A plasma (average 1210.5 ±27.9 mL). Patient 3 received a total of six procedures, four out of six procedures with AB+A plasma (average 1009.8 ±80.3 mL). Patient 4, control, received AB plasma only. Percent of A plasma volume exchanged ranged between 23.8% and 47.8%. Haptoglobin, LDH, hemoglobin, and total bilirubin were monitored and trends were comparable with the control patient. The patients had a negative follow up direct antiglobulin test, adequate platelet recovery and a favorable clinical outcome with treatments. Conclusions TPE was effectively performed without evidence of increased hemolysis using up to 47.8% of low titer A plasma. This approach can reduce strains on limited supplies of AB plasma whereas providing a vital treatment alternative for AB patients undergoing TPE with plasma replacement.

Benchmarking the centralized urgent plasma exchange service for patients admitted with a diagnosis of suspected acquired thrombotic thrombocytopenic purpura at a large healthcare system

“…There was more variability in the time to initiation for patients with the AB blood group, likely because of delays in obtaining sufficient quantities of compatible plasma for the exchange. Some of the hospitals served by the centralized apheresis service are now utilizing low‐titer group A plasma (anti‐B titer less than 50 at immediate spin phase using the tube methodology) during the TPE procedure if sufficient group AB plasma is not available 12 …”