Streptococcus pyomyositis occurring in a patient with dermatomyositis in a country with temperate climate.

We describe a man in whom pyomyositis developed in a temperate climate. Three facts make this case unique. First the pyomyositis developed in someone with underlying dermatomyositis, this being the second reported case to our knowledge. Second, the organism involved was a Streptococcus and not a Staphylococcus as in most cases described, and the course of the disease was acute and not subacute as is usually reported. Finally, contrary to most described cases, surgical drainage was not necessary, probably because of the early diagnosis. Pyomyositis should be considered a possible cause of localized pain in patients with underlying inflammatory muscle disease.