Figure 2.

(A) Photomicrograph of peripherally radiating filaments of the actinomycotic granule (i), (tissue Gram stain, 100×). (ii) Granule is surrounded by trabecular bone. Note the deep-purple Gram-positive filaments (arrows), (tissue Gram stain, 20×). (B) Photomicrograph of deeply stained basophilic actinomycotic granule with prominent peripheral cubs (white arrows) surrounded by polymorphonuclear leucocytes (black arrows) embedded in an abscess (A), (Giemsa stain, 40×). (C) Periphery of actinomycotic granule (i). Note the branching filaments and cocoid elements. (ii) Gomori methamine silver stain of actinomycotic granule (arrows) embedded in an area of suppurative necrosis between bone trabeculae (10×). (D) Photomicrograph of an actinomycotic granule bordered by eosinophilic Splendore–Hoeppli material (between arrows), embedded in fibrino-purulent exudate and surrounded by trabecular bone (B). Note the numerous polymorphonuclear leucocytes within the matrix of the granule (H&E stain, 20×).