Serum amyloid protein A (SAA): an indicator of inflammation in AIDS and AIDS-related complex (ARC).

The acute phase protein serum amyloid A (SAA) and C-reactive protein (CRP) were measured in a group of 30 homo- and bisexual males with AIDS, 31 males with AIDS-related complex (ARC) and 23 healthy male homosexual controls (HC) in Copenhagen. The mean values of SAA and CRP were significantly higher in the AIDS group compared to the two other groups. SAA was elevated also in the ARC group, whereas the mean CRP value was normal. No increase in SAA and CRP was found in the HC group. The AIDS patients with Pneumocystis carinii infections had the highest SAA values, those with Kaposi's sarcoma the lowest. The elevations in SAA and CRP preceded episodes of acute opportunistic infections often by several days before the infectious agents were identified. We conclude that patients with AIDS are able to establish an acute phase response as reflected by elevated SAA and CRP, and that measurement of these proteins may be of diagnostic and prognostic value.