Fig. 2

Pathological findings and staining of bacteria. a Hematoxylin and eosin (H&E) stain of the first excised mass showing large numbers of fibrinous exudate (double →) and chronic inflammation with a few mononuclear cells (→) and macrophage (→) (×200). b Gram’s staining of blood cultures showing large numbers of C. striatum (×1000). c Gram’s staining of the second excised vegetation showing Corynebacterium (×1000). d Gram’s staining and (e)Wright’s staining of the first excised mass for Corynebacterium (×1000). f Corynebacterium can not be found in second excised vegetation by Gram’s staining (×400)