Serological crossmatching (or simply 'crossmatch') is a laboratory test performed before transfusion to ensure compatibility between a specific donor red blood cell (RBC) unit and a potential recipient. Its primary goal is to detect **clinically significant antibodies** in the recipient's serum that could react with antigens on the donor's RBCs, potentially causing a hemolytic transfusion reaction. The traditional serological crossmatch involves two main phases: 1) **Immediate Spin (IS) Phase**: The recipient's serum and donor RBCs are mixed, centrifuged immediately at room temperature, and examined for agglutination or hemolysis. This phase primarily detects **ABO incompatibility** due to IgM antibodies. 2) **Antiglobulin (Coombs) Phase**: The mixture is incubated at 37°C to allow IgG antibodies to bind, then washed to remove unbound serum, and anti-human globulin (AHG) reagent is added. This phase detects **clinically significant IgG antibodies** (e.g., anti-D, -K, -Fya) that require 37°C and AHG for detection. A negative result in both phases indicates serological compatibility. Many labs now use an 'electronic crossmatch' for low-risk patients, which relies on computer checks of ABO compatibility and a negative antibody screen.

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Zambia

• Joseph Soko – 101 pts

• Visual Pathway Lesions
• Positive and Negative Symptoms
• Hallucinations and Delusions
• Antipsychotic Medications
• Emergency: Environmental Emergencies