Polymyositis or dermatomyositis is a nonsuppurative, nonspecific inflammatory disease of the striated muscles and the surrounding areolar tissue. It frequently involves the skin and occasionally the mucous membranes and is characterized by pain, fever and edema. It may be acute, subacute or chronic.
In 1887, almost simultaneously, Hepp,1 Unverricht2 and Wagner3 independently published reports of cases of this condition. Hepp called it "pseudo-trichinosis"; Wagner and Unverricht described it under the name of "polymyositis acuta progressiva." The morbid pathology of this type of disease was described about seventy years ago by Virchow. In 1891 Strümpell4 collected ten cases from the literature and added one that he had observed. His clinical and pathologic descriptions of this entity are classic. Since Strümpell's report there have been several excellent treatises on the subject by Senator,5 Lorenz,6 Steiner,7 Kader,8 Oppenheim,9 Rotky10 and others. In the