Anti-D Immunoglobulin Classification
Anti-D immunoglobulin is a blood product, not a blood component. 1
Definition and Source
Anti-D immunoglobulin is explicitly classified as a "pooled, biological blood product" in international consensus guidelines 1. This classification is critical because:
- It is derived from pooled human plasma of hyperimmunized donors who have been deliberately immunized to produce high-titer anti-D antibodies 2
- The product undergoes purification and processing from donor plasma, distinguishing it from direct blood components like red cells, platelets, or fresh frozen plasma 1
- As a blood-derived product, it carries theoretical risks of pathogen transmission, though modern manufacturing processes include extensive viral inactivation steps 2
Clinical Implications of Blood Product Classification
The blood product designation has several important practical consequences:
Informed Consent and Traceability
- Patients must receive written information about both the condition being prevented (hemolytic disease) and the blood-derived nature of anti-D immunoglobulin before administration 2
- Oral consent is required prior to administration, and refusal must be documented in the medical record 2
- Legal requirements for traceability apply to anti-D immunoglobulin prescription and administration, similar to other blood products 2
Religious and Cultural Considerations
- Anti-D immunoglobulin may not be acceptable to certain patient populations, such as Jehovah's Witnesses, who refuse blood products 1
- This limitation affects treatment options—for example, in pediatric immune thrombocytopenia, anti-D cannot be used for patients who decline blood products, whereas corticosteroids remain an option 1
Safety Profile Related to Blood Product Status
- Despite being a blood product, current anti-D preparations show no recent evidence of HIV, HCV, HBV, or HTLV-1 transmission due to rigorous manufacturing safeguards 1
- The product can cause hemolysis as it works by coating fetal Rh-positive red cells, with rare but serious cases of intravascular hemolysis, disseminated intravascular coagulation, and renal failure reported 1
- A black box warning exists for fatal intravascular hemolysis, though this remains a rare event 1
Contrast with Blood Components
Blood components (red cells, platelets, plasma, cryoprecipitate) are separated directly from whole blood donations without the extensive processing and pooling that characterizes blood products like anti-D immunoglobulin, intravenous immunoglobulin (IVIG), and clotting factor concentrates 1.