Streptococcal necrotising myositis of obturator internus and piriformis in a type 2 diabetic patient presenting as sepsis of unknown origin.

This report describes a case of necrotising myositis of the obturator internus and piriformis muscles. Necrotising myositis is a rare result of group A streptococcal infection. It is usually fatal and has not been described previously in the obturator internus and piriformis. We describe how, following presentation to an emergency department, rapid diagnosis was arrived at by clinically guided radiological investigation. The report considers the possible aetiology of the condition, the diagnosis and its management, and reviews the relevant literature.