Suspected hemolysis caused by type A therapeutic plasma exchange in a patient with AB subtype miss detected

Abstract

Objective To investigate the serological changes of blood type and whether hemolytic reactions occurred in a patient with ABw subtype after type A therapeutic plasma exchange(TPE) retrospectively. Methods The ABO blood group identification and genotyping was carried out by microcolumn gel method, microcolumn glass bead method, saline tube method and absorption-elution test, and the laboratory results before and after TPE were analyzed. Results The patient underwent 2 000 mL type A TPE in other hospitals and was transferred to our hospital. On the second day of hospitalization, the test showed consistency between forward and reverse blood typing. On the third day, the detection showed that Bc was ±~1+ , and discrepancy was found between forward and reverse typing. The presence of B antigen was confirmed through tube method and human anti-B absorption-elution test, and was identified as ABw03 by molecular biological method. After type A TPE, Hb and Plt both temporarily decreased, creatinine slightly increased, ALT and AST continued to decrease, while TBIL, DBIL and IBIL showed a temporary decrease followed by an increase, indicating a slight hemolytic reaction. Conclusion Infusion of large volume of plasma may cause hemolytic reactions when ABO subtype patients contain weak A or B antigens.The blood type should be strictly identified according to the ABO blood type forward and reverse typing standards. Additional laboratory tests combined with molecular biology techniques are required for weak agglutination, which can reduce the missed detection of ABO subtypes and reduce the occurrence of transfusion reactions.

Keywords

• hemolytic transfusion reaction
• microcolumn gel card
• abo subtype
• missed detection