Snap frozen section of muscle is adequate And shows transvers muscle bundles. There is variation in muscle fiber size , many atrophic muscle fiber are noted. Dence endomysial and interstitial lymphocytic of infiltrate is noted. There is evidence of mypophagocytosis and necrosis of muscle fibers. Many regenerating fiber showing basophlia is seen there is no evidence of granuloma vasculitis and amyloid is seen in this biopsy examined. Immunohistorology : MHCI -- Focal increased expression in subsarcollema MHCII : Increase expression in subsarcollema MAC – Focal increase expression in small vessels C4d - Non contriburtory Combining morphogical and immunohistochemistry findings features are of inflammatory myopathy consistent with polymyositis. DIAGNOSIS Muscle (left , vastus lateral is) : consistent with Mayopathy , Inflammatory