Characterized by classic triad of uveitis, arthritis and urethritis. Develops post bacterial infection, chlymedia, salmonella, campylobacter, GI tract infection. Clinical findings sacroilitis, polyarthritis, enthesopathy, sausage digit. Enteropathic arthritis is an inflammatory spondyloarthropathy where there is direct GI invlment such as IBD, reactive arthristis following bacterial infectiono of GI tract. These are inflammatory myopathies of unclear etiology.
Clinical hallmark is proximal limb and neck weakness sometimes associated with muscle pain.
Pathologic findings are focal muscle necrosis, regeneration and inflammation. There may be systemic involvement as well. Primary idiopathic polymyositis. Primary idiopathic dermatomyositis. Dermatomyositis and polymyositis assoc with malignancy.