Antigen-Induced Experimental Septic Arthritis in Rabbits after Intraarticular Injection of Staphylococcus aureus

Abstract

With the Dumonde-Glynn model of antigen-induced arthritis, a rabbit model was developed to examine the histopathologic differences between normal and arthritic joints in the same animal infected by intraarticular injections of Staphylococcus aureus. Microscopic examination of whole joint sections and a quantitative histopathologic scale were used to compare changes in all the articular components of 17 normal and 17 arthritic joints infected for less than two weeks. The histological changes were more severe in infected arthritic joints than in infected normal joints (mean +/- SD total histology score, 13.8 +/- 2.4 and 9.3 +/- 4.0, respectively; P less than .001). In infected arthritic joints, subsynovial abscesses extended into subchondral bone via the pannus of chronic synovitis at articular margins and intraarticular attachments of cruciate ligaments, rather than by initial cartilage destruction and direct extension into subchondral bone.

Phosphocitrate prevents disease progression in murine progressive ankylosis

“…Histologic sections were examined and rated by one blinded observer (MLM). Severity of arthritis was quantitated according to a modification of an articular histopathologic grading scale described previously (14). Features of peripheral joints were graded 0-4, as follows: synovial fluid (cellular and proteinaceous material seen within the joint space): 0 = none, 1 = trace amount, 2 = small amount, 3 = moderate amount, and 4 = large amount distending the capsule; synovial membrane: 0 = normal, 1-2 cells deep, 1 = 3-6 cells deep, 2 = >6 cells deep, 3 = hyperplasia plus focal necrosis or ulceration, and 4 = destroyed; subsynovium: 0 = fibroareolar without increased cellularity, 1 = hypercellular, 2 = inflammation/focal necrosis, 3 = fibroblastic proliferation, and 4 = chondroid metaplasia; cartilage: 0 = intact, l = superficial disruption of articular surface or superficial erosions, 2 = moderate cartilage erosions, 3 = deep marginal erosions into bone, and 4 = extensive ankylosis; periarticular bone: 0 = normal contour, 1 = marginal new bone proliferation, 2 = small syndesmophyte, 3 = large syndesmophyte, and 4 = complete ankylosis.…”

Experimental Staphylococcus aureus arthritis in mice

“…In patients with rheumatic diseases, this value is even higher, approaching 75% (3). Laboratory models of bacterial arthritis have been used previously (5,12,16,21,24,25,(27)(28)(29). In most instances bacteria have been injected intraarticularly, usually utilizing the rabbit as an experimental animal.…”

Development of an experimental model of septic knee arthritis in rats through intra-articular inoculation of Staphylococcus aureus

“…20 However, most intra-articular models of arthritis have been developed for rabbits. 6,13–18 Concerning rodents, a few models have been developed for hamsters and guinea pigs, 21 but rats were lacking such models until now. Perhaps the scarcity of intra-articular models for rodents could be explained by the anticipated technical difficulties in puncturing the joints of small animals such as rats.…”

“…Many rodent models of septic arthritis are based on the injection of pathogens through the haematogenous route, 1,2,6–11 but these models have several obvious disadvantages. For instance, it is impossible to anticipate precisely which joint will become infected, even if the targeted joint is previously damaged to improve the success rate.…”