Prevalence and factors associated with acute transfusion reactions among patients receiving blood transfusions in regional referral hospitals in dar es salaam, Tanzania Free

Blood transfusion is a lifesaving procedure, essential in the management of various medical and surgical conditions including severe anemia, infection, bleeding and malignancies. Despite its usefulness, it may be associated with adverse reactions resulting from various pathophysiology. Acute transfusion reactions (ATR) are adverse events occurring within 24 hours post-transfusion. These reactions range from mild to severe and remain a major safety concern for both patients and providers. Due to limited resources for preparation of blood products, most regional hospitals in the country of Tanzania transfuse whole blood. This poses an increased risk for acute transfusion reactions due to unnecessary transfusion of plasma and other components. There is a significant paucity of data on transfusion reactions in Tanzania, hence this study was conducted to determine the prevalence of acute transfusion reactions and identify the associated risk factors.

To determine the prevalence and factors associated with ATRs among patients receiving blood transfusions in regional referral hospitals in Dar es Salaam, Tanzania.

A cross-sectional study was conducted from October 2024 to March 2025 in three regional referral hospitals which are Amana, Mwananyamala, and Temeke hospitals in Dar es Salaam. A total of 151 patients receiving whole blood for severe anemia were enrolled. Transfusion data, which included patient demographics, blood product and dose, and transfusion indication were collected using the Tanzania Ministry of Health transfusion monitoring forms. Immunohematology tests including ABO grouping, compatibility testing, and direct antiglobulin test (DAT) were performed in all patients with ATRs. Statistical analysis using STATA v25 involved bivariate and multivariable Poisson regression was utilized to determine factors associated with ATRs, expressed as adjusted prevalence ratios (aPRs) with 95% confidence intervals.

A total of 151 participants were included in the study. Females accounted for 53.6% of the total population. The median age of all participants was 30 years (IQR: 21–41), with the majority aged 18–39, (58.3%). Those who were aged below 18 and above 59 years accounted for 13.2%, and 8.6%, respectively. 51 (33.8%) patients developed ATRs. Underlying diagnoses of those with ATR included gastrointestinal bleeding/renal disease (29.6%), hematological disorders (41.5%), infection (39%), pregnancy (16%), and trauma (20%). Among those who developed ATR, Amana hospital had 20 patients (39.2%), Mwananyamala hospital with 16 patients (31.4%) and Temeke hospital had 15 patients (29.4%). The most common reactions were febrile non-hemolytic transfusion reactions (43.1%), followed by allergic reactions (31.4%), post-transfusion purpura (9.8%), anaphylaxis (7.8%), acute hemolytic reactions (3.9%), and transfusion-associated circulatory overload (3.9%). DAT was positive in 24 (15.7%) of ATR cases but the subtype of antibody implicated was not determined. Multivariable analysis showed significantly lower ATR risk among patients with obstetric and gynecological diagnoses (aPR = 0.39; 95% CI: 0.25–0.60; p < 0.001). In contrast, blood groups AB (aPR = 2.84; p = 0.015), B (aPR = 2.16; p = 0.043), and O (aPR = 2.53; p < 0.001) were associated with higher ATR risk compared to group A. No significant associations were found with age, sex, transfusion dose, or health facility.

A high prevalence of ATRs was observed, predominantly febrile and allergic reaction, likely exacerbated by the exclusive use of non-leukoreduced whole blood. Blood group and clinical diagnosis were significant predictors of ATRs, while traditional demographic variables were not. The detection of positive DAT in some cases suggests alloimmune mechanisms not routinely addressed in current transfusion practice. From this study, we believe that four mechanisms may lead to a decrease in ATR: transitioning from whole blood transfusion to component therapy, use of pre-storage leukoreduction, introduction of routine antibody screening and extended red cell phenotyping, and integration of hemovigilance systems across all transfusion sites. These strategies are critical to reducing preventable transfusion-related morbidity in resource-limited settings and set us up for future studies in the field.