Concentrations of serum amyloid A in serum and synovial fluid from healthy horses and horses with joint disease.
OBJECTIVE
To determine serum amyloid A (SAA) concentrations in serum and synovial fluid from healthy horses and horses with joint disease and assess the effect of repeated arthrocentesis on SAA concentrations in synovial fluid. Animals-10 healthy horses and 21 horses with various types of joint disease.


METHODS
Serum and synovial fluid samples were obtained from each horse. In 5 of the 10 healthy horses, arthrocentesis was repeated 9 times. Concentrations of SAA were determined via immunoturbidometry.


RESULTS
Serum and synovial fluid SAA concentrations were less than the assay detection limit in healthy horses and did not change in response to repeated arthrocentesis. Synovial fluid SAA concentrations were significantly higher in horses with suspected bacterial joint contamination or infectious arthritis, or tenovaginitis than in healthy controls, and serum concentrations were significantly higher in horses with infectious conditions than in the other groups. Neither serum nor synovial fluid SAA concentrations in horses with low-inflammation joint conditions differed significantly from those in healthy controls. Concentrations of SAA and total protein in synovial fluid were significantly correlated.


CONCLUSIONS
Synovial fluid SAA concentration was a good marker of infectious arthritis and tenovaginitis and appeared to reflect changes in inflammatory activity. The advantages of use of SAA as a marker include the ease and speed of measurement and the fact that concentrations in synovial fluid were not influenced by repeated arthrocentesis in healthy horses. Further study of the SAA response in osteoarthritic joints to assess its usefulness in diagnosis and monitoring of osteoarthritis is warranted.
Jacobsen
Stine
S
Department of Large Animal Sciences, The Royal Veterinary and Agricultural University, Dyrlaegevej 48, DK-1870 Frederiksberg C, Copenhagen, Denmark.
Thomsen
Maj Halling
MH
Nanni
Simone
S
D000818:Animals; D001170:Arthritis, Infectious / Q000097:blood / Q000378:metabolism / Q000662:veterinary*; D006262:Health; D006734:Horse Diseases / Q000097:blood / Q000378:metabolism*; D006736:Horses; D000685:Serum Amyloid A Protein / Q000032:analysis*; D013582:Synovial Fluid / Q000378:metabolism*; D013717:Tenosynovitis / Q000097:blood / Q000378:metabolism / Q000662:veterinary*
D000685:Serum Amyloid A Protein