Blood Group and Rh Factor Determination
Blood group and Rh factor determination is a laboratory test that identifies a person’s blood group according to the ABO system and determines the presence or absence of the Rh factor. This information is vital for safe blood transfusions, pregnancy planning to prevent Rh incompatibility, and emergency medical interventions.
ABO System
Blood groups in the ABO system are determined by the presence or absence of antigens A and B on the surface of red blood cells:
- Group O (I) — no A or B antigens.
- Group A (II) — presence of antigen A.
- Group B (III) — presence of antigen B.
- Group AB (IV) — presence of both antigens A and B.
Rh Factor
The Rh factor is a protein (antigen) that may be present (Rh positive) or absent (Rh negative) on red blood cells. The presence or absence of Rh classifies blood as Rh-positive or Rh-negative.
Testing Method
Blood is taken from a vein or finger and mixed with reagents containing monoclonal antibodies anti-A, anti-B, and anti-D (for Rh). Based on agglutination (clumping) reactions, the blood group and Rh factor are determined:
- Agglutination with anti-A — Group A.
- Agglutination with anti-B — Group B.
- Agglutination with both — Group AB.
- No agglutination — Group O.
- Agglutination with anti-D — Rh positive.
- No agglutination with anti-D — Rh negative.
Significance of the Test
- Ensures safety during blood transfusions and blood component therapy.
- Assists in pregnancy planning and management to prevent Rh incompatibility.
- Important for diagnosis and preparation before surgeries.
- Provides essential information for emergency medical care.
Recommendations
Blood group and Rh factor determination is recommended for all patients during initial medical examinations, women planning pregnancy and during pregnancy, and before surgeries and transfusions.
This test is simple, quick, and essential, playing a key role in modern medicine and ensuring patient safety during many medical procedures.