<![CDATA[Patients with Chronic Kidney Disease (CKD) undergoing maintenance hemodialysis are highly susceptible to severe anemia and frequently require repeated long-term blood transfusions. This therapeutic intervention exposes patients to non-ABO foreign red blood cell antigens, potentially triggering alloimmunization through the formation of irregular antibodies. These antibodies may compromise transfusion safety and complicate compatibility testing (crossmatching) in transfusion laboratories. This study aimed to determine the prevalence and specificity of irregular antibodies among CKD patients at the Referral Laboratory of the Blood Donor Unit, Indonesian Red Cross (PMI) Semarang City. This descriptive quantitative study analyzed secondary laboratory records from 55 CKD patients collected between July 2020 and September 2025. Immunohematological data included ABO and Rh blood grouping, antibody screening using the Indirect Antiglobulin Test (IAT), Direct Antiglobulin Test (DAT), and antibody identification using a 10-cell red blood cell panel. The results showed that most participants were aged 40–60 years (50.9%), with blood group O being the most prevalent (36.4%). Of the total samples, 17 patients (30.9%) tested positive for irregular antibody screening. Further antibody identification detected Anti-M (MNS blood group system) in two cases (11.8%) and Anti-e (Rh blood group system) in two cases (11.8%). The majority of positive cases (13 patients; 76.4%) demonstrated non-specific antibody reactions. Most non-specific results are thought to be associated with the potential presence of autoantibodies, particularly in patients with a positive Direct Antiglobulin Test (DAT). Patients with chronic kidney disease (CKD) face a relatively high risk of developing irregular antibodies. This condition creates a masking effect that conceals other alloantibodies and leads to major incompatibility during crossmatching. Therefore, it is recommended that reference laboratories routinely employ adsorption techniques to ensure the safety of blood for transfusion.]]>
