Red blood cell alloimmunization in transfused oncology patients at a high-complexity center in Colombia

Red blood cell transfusion is essential for managing anemia in cancer patients but can induce erythrocyte alloimmunization, particularly against Rh (anti-E) and Kell (anti-K) antigens, which complicates transfusion compatibility and increases the risk of hemolytic events. This study assessed the prevalence and profile of irregular antibodies in transfused oncology patients at a high-complexity center.

A retrospective descriptive study analyzed medical records of 179 adult patients with solid tumors or hematologic neoplasms who received red blood cell transfusions. Demographic, clinical, and immunohematologic variables were analyzed. Irregular antibody detection was performed using gel agglutination (ID-Card LISS/Coombs) processed on the IH 500 analyzer. Statistical analysis was descriptive and bivariate, using Chi-square, Fisher's exact, or Wilcoxon tests, as appropriate.

Of the study population, 65.9% were female, with a median age was 61 years. Solid tumors predominated (73.7%). Blood group O (61.5%) and RhD positive status (83.8%) were most common. Among clinically significant alloantibodies, anti-E (26.3%) and anti-K (15.1%) were the most frequently identified specificities. In addition, autoantibodies were detected in 30.2% of patients and were significantly more common in patients with hematologic neoplasms (42.6% vs. 25.8%; p = 0.031). These patients also required more transfusions and crossmatches after a positive irregular antibody screen (IAS) (p < 0.001).

Alloimmunization is frequent in transfused oncology patients, primarily involving Rh and Kell systems, complicating compatible unit procurement. Antibodies against Duffy and Kidd systems add further challenges. Extended phenotyping for Rh and Kell could reduce alloimmunization risks and enhance transfusion safety in this population.