In B a few inflammatory cells are present around muscle fibers. A macrophage at the arrow is digesting a fiber. This low-power view of another fascicle shows active inflammation and muscle fiber degeneration and regeneration.
Some muscle fibers are normal in size and dark pink.
Others, which are degenerating, are smaller and lighter pink. Small fibers with a bluish tinge and enlarged nuclei are regenerating fibers. Inflammatory cells including lymphocytes and macrophages cannot be distinguished from muscle fiber nuclei at this power. D At higher magnification, some of the hypercellularity is caused by proliferation of the muscle nuclei and some is caused by the presence of lymphocytes and macrophages between muscle fibers. Note especially the capillaries, which have enlarged endothelial cells.