Prevalence of the Direct Antiglobulin Test and Its Clinical Impact on Multiply Transfused Thalassemia Patients: A Prospective Study Conducted at a Tertiary Care Center in Northern India.

OBJECTIVE

This study was conducted to estimate prevalence of direct antiglobulin test (DAT) positivity and its impact on transfusion support in patients with thalassemia.

METHODS

The DAT testing was performed for patients with β-thalassemia who received transfusion from November 2021 to March 2022. Elution was done for DAT-positive samples.

RESULTS

Of 180 patients, 21 (11.6%) were DAT positive. Immunoglobulin G (IgG) was present in 4 (19%) and IgG+C3d was present in 8 (38%). Only complement was present in 9 (42.8%) patients. The IgG-reactive DATs were associated with pan-reactive eluate. Patients who were DAT-positive had significantly higher levels of serum bilirubin, ferritin, and IgG than those who were DAT-negative.

CONCLUSION

Autoantibody formation in multiply transfused thalassemia patients is common and merits equal attention as alloimmunization. It is particularly important as DAT-positive red blood cells may undergo clinically significant hemolysis, which may increase the transfusion requirements with associated sequalae such as increased serum ferritin and splenomegaly.