Evaluation of a red cell agglutination test for detection of Australia antigen (HG Ag)

An investigational red cell agglutination (RCA) test was evaluated for sensitivity in detecting and titering hepatitis B antigen (HB Ag) in comparison with two counterelectrophoresis (CEP) systems and a solid-phase radioimmunoassay (RIA). The RCA procedure was found to be significantly more sensitive than the CEP methods and compares favorably in sensitivity with the solid-phase RIA, detecting even lower concentrations of the HB Ag. Since the RCA test can be completed in 2 to 3 h and requires relatively inexpensive equipment, it offers a highly sensitive and rapid procedure suitable for use in blood banks to screen donors or detect low levels of antigen in serum of patients.