Equine Septic Arthritis and Serum Amyloid A

• Main Author: Ludwig, Elsa Karen
• Other Authors: Veterinary Medicine
• Format: Others
• Published: Virginia Tech 2016
• Subjects: equine; septic arthritis; synovitis; acute phase protein; serum amyloid A
• Online Access: http://hdl.handle.net/10919/71757

Bacterial infection within a joint, septic arthritis, is a serious condition in horses that can lead to long-term joint disease if the infection is not resolved quickly. Equine septic arthritis is diagnosed primarily based on clinical signs and synovial fluid cytology. Septic synovial fluid is characterized by significant elevations in total protein (TP) and total nucleated cell count (TNCC). However, in some cases it can be difficult to distinguish between septic arthritis and non-septic joint inflammation (synovitis) based on clinical signs and synovial fluid cytology alone. A rapid assay to help confirm septic arthritis would be advantageous. A new assay to quantify the major equine acute phase protein, serum amyloid A (SAA) may fulfill this need. Serum amyloid A increases in the body in response to injury, infection, and inflammation and shows promise as a useful tool in confirming a diagnosis of sepsis, as inflammation causes mild increases in SAA and infection causes marked elevations. In our study, serial serum and synovial fluid samples were collected from horses with experimental models of synovitis and septic arthritis, synovial fluid cytology was performed, and serum and synovial fluid SAA were quantified. Synovial fluid TNCC and TP concentrations increased significantly following induction of both models. Serum and synovial fluid SAA concentrations remained normal in synovitis horses and increased significantly in septic arthritis horses. Any elevation in serum or synovial fluid SAA above normal values may be supportive of synovial sepsis since synovial inflammation alone did not result in SAA elevations in our model. === Master of Science