Abstract: Objective To elucidate the mechanisms of platelet antibody production, analyze their distribution across diverse populations, investigate associations with primary diseases and laboratory parameters, and assess their impact on test outcomes—with the ultimate goal of providing evidence-based recommendations for optimizing platelet antibody detection protocols and transfusion strategies. Methods A total of 29 782 patients were enrolled in this study, who had undergone platelet antibody testing at Zhujiang Hospital of Southern Medical University between March 2023 and April 2025. Platelet antibodies were detected using the solid-phase agglutination assay. We analyzed the relationships between platelet antibody production, demographic distribution, disease spectrum, and relevant laboratory indicators. Results Among the 29 782 hospitalized patients (15 353 males and 14 429 females), 864 cases tested positive for platelet antibodies, resulting in an overall positivity rate of 2.90%. Notably, the positivity rate was significantly higher in females than in males (3.37% vs. 2.46%, P<0.05). Females with a history of pregnancy had a higher positivity rate than those without (3.39% vs. 3.07%, P<0.05). Patients with a history of blood transfusions exhibited a higher positivity rate than those without (4.91% vs. 2.40%, P<0.05). Significant differences in positivity rates were observed across disease categories: immune system diseases had the highest rate, followed by hematologic diseases, with obstetric conditions ranking third (P<0.05). The distribution of different types of pregnancy complications also varied significantly with platelet antibody positivity (P<0.05). The results of total white blood cell (WBC) count, platelet (PLT) count, prothrombin time (PT) and hematocrit (Hct) in patients with positive platelet antibody were significantly different from those in negative patients (P<0.05). Female sex, history of pregnancy (in females), history of blood transfusion, low PLT, and low Hct were identified as independent risk factors for platelet antibody positivity. Conclusion Patients with a history of blood transfusion, pregnancy (particularly females), and female patients showed a relatively higher platelet antibody positivity rate. Immune system disorders and hematologic diseases demonstrated markedly higher platelet antibody positivity rates compared to other disease categories. Positivity rates also increased in patients with pregnancy complications. Platelet antibody positivity was closely associated with sex, pregnancy history, transfusion history, PLT and Hct, while also showing some correlation with WBC and PT.These findings enable more precise identification of high-risk populations and optimization of transfusion strategies.

Key words: Platelet antibody, Blood transfusion, Transfusion history, Obstetric history, Laboratory indicators