Analysis of anti-M antibody status and blood transfusion strategy in Hunan, China.

Background: By analyzing the detection rate of anti-M antibody in patients with the MNS blood group system in the Hunan area, we aimed to explore its clinical significance and blood transfusion strategy. Methods: We retrospectively analyzed the clinical data of patients who had been confirmed to contain anti-M antibodies through serological methods such as the saline tube method and cassette anti-human globulin method. Results: Irregular antibody screening tests had been applied to 94,452 patients, from which 652 results were positive. Among those positive patients, 93 cases were positive for anti-M antibodies, accounting for 14.26% of the positive rate of irregular antibodies; 11 cases had a blood transfusion history, accounting for 11.8%; 59 cases had a pregnancy history, accounting for 63.4%; and 2 cases had a transplant history, accounting for 2.2%. The patients with anti-M antibodies included 23 pregnant woman, accounting for 24.7%, and 19 tumor patients, accounting for 20.4%. A total of 66 cases were immunoglobulin M (IgM) + immunoglobulin G (IgG) class, accounting for 71.0%, 26 cases were IgM class, accounting for 28.0%, and 1 case was IgG class, accounting for 1.0%. Conclusions: The detection rates of anti-M antibody in the Hunan area and unexpected antibodies in literature reports are mainly related to a pregnancy history, and the type of antibody is predominantly IgM + IgG class. The clinical significance of anti-M antibody cannot be ignored, and three media should be used for cross-matching of blood wherever possible to ensure the safety of blood transfusion.