Erosive arthritis and spondyloarthropathy in Old World primates.

Presence of spine and sacroiliac involvement and the nature and distribution of the erosive lesions allow definitive diagnosis of spondyloarthropathy. Thus, spondyloarthropathy was identified in Theropithecus, Papio, Cercopithecus, Macaca, Colobus, Presbytis, and Hylobates. Only monarticular erosive disease was present in prosimians, precluding a diagnosis of spondyloarthropathy for that group. The distribution of erosive disease and axial joint involvement in 1,349 non-prosimian Old World primates is quite characteristic of that noted in human psoriatic arthritis. While Reiter's syndrome must also be considered, the histologic appearance of skin lesions in Macaca is characteristic of psoriasis. Evidence of spondyloarthropathy abounds in the literature of primate skeletal disease. Environmentally based contagions may be important in the pathophysiology of spondyloarthropathy. The wide geographic distribution of the phenomena in monkeys suggests a "panendemic," with limited individual susceptibility (compared to that noted in gorillas and chimpanzees). Identical occurrence of erosive arthritis/spondyloarthropathy in free-ranging and artificially restrained animals suggests that spondyloarthropathy can validly be studied in artificially restrained populations. This perspective should allow application of human therapeutic approaches to and perhaps improve the quality of life for artificially restrained, afflicted individuals.