You have mentioned that your sister has been diagnosed as suffering from dermatomyositis. If it is a confirmed diagnosis (biopsy, EMG, muscle enzyme levels, classical skin lesions of dermatomyositis including Gottrons papules, shawl sign, nail-fold capillary abnormalities, etc.) then Gold injections are not among the standard known, proven therapy for this disease. You will have to discuss this matter with the treating rheumatologist and pointedly ask for any scientific evidence that has shown proof of efficacy of Gold therapy in dermatomyositis. To my knowledge, there is no such scientific evidence to date.