Abstract Background and Objectives Acute blood complications form the most frequent and important reactions among the blood transfusion adverse effects acute hemolytic reaction, bacterial contamination, and transfusion related acute lung injury (TRALI) are the most frequent causes of death following blood transfusion. Materials and Methods In this descriptive prospective study, 2633 patients hospitalized in surgical and non-surgical departments of 11 hospitals having received blood transfusion were evaluated for acute blood transfusion reactions. Results Among these patients, 20 (0.8%) encountered acute blood transfusion reactions. Out of this group of patients, eight experienced febrile non-hemolytic transfusion reactions, nine had allergic reactions, one developed blood group incompatibility, and two disseminated intravascular coagulation (DIC). Conclusions This study indicates that the most prevalent blood transfusion reactions were fever and allergy (0.3%). This reported rate (0.5-6%) is lower than the global rate. The rate of blood group incompatibility in this study was 0.03%, showing a higher prevalence than the global rate (0.004%). Key words : Allergy, Blood transfusion, Blood group incompatibility, DIC. | 
