A rapid method for measuring serum amyloid A protein by latex agglutination nephelometric immunoassay.

Serum amyloid A protein (SAA) is a sensitive acute phase reactant. We developed a method for the rapid measurement of human SAA in serum by kinetic nephelometry of anti-SAA antibody-coated latex agglutination. Measurement takes less than 6 min using an automated analyser. Standardization of the assay employs SAA-enriched high density lipoprotein as the primary standard. The values determined by our new method and by conventional enzyme-immunoassay showed good agreement (r = 0.988). The normal range was 0.17-10.0 mg/L [mean(SD)]. This rapid method should prove useful in clinical laboratories.