Sree Chitra Tirunal Institute for Medical sciences and Technology ...

INTRODUCTIONThe inflammatory myopathies are simply those disorders in which the primarypathological process is inflammation within muscle. In most, the main clinicaiconsequence is weakness, much less frequently pain. This definition thus excludesmyopathies with secondary inflammation in muscle, such as some of the musculardystrophies, and conditions in which the inflammatory process is in associated tissuesrather than muscle itself, such as polymyalgia rheumatica. These latter conditions areparticularly important as they may be misdiagnosed and mistreated as being forms ofmyositis. ·The inflammatory myopathies are rare. No accurate figures for incidence orprevalence are available but if one takes the two most common conditions,dermatomyositis and inclusion body myositis, their combined annual incidence ISprobably less than 200 new cases per annum in the UK (population ~60 million).In perhaps 70% of cases, the diagnosis and management are straightforward andsuccessful· With respect to drug treatment there is an absolute dearth of randomisedcontrolled trials and the best advice that can be offered is based on "expert opinion".Multicentre trials are desperately needed6