IPLab:Lab 9:Actinomycosis

Images

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  This is a low-power photomicrograph of the retroperitoneal abscess. At this magnification, multiple dark-staining foci can be appreciated. These foci are Actinomyces colonies (arrows). These colonies are known as "sulfur granules" because in gross specimens they are visible to the naked eye as yellow grains, thus resembling grains of sulfur.
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  This is a higher-power photomicrograph of an abscess demonstrating a pocket of purulent exudate that contains numerous actinomycotic colonies (arrows).
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  This is a higher-power photomicrograph of actinomycotic colonies in the abscess.
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  This is an even higher-power photomicrograph of actinomycotic colonies in the abscess. The filamentous nature (arrows) of the actinomyces organisms in these colonies can be appreciated.
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  This is a high-power photomicrograph of an actinomycotic colony. The filamentous nature (arrows) of the actinomyces organisms is more easily appreciated at this power.

An abscess is a collection of pus (white blood cells) within a cavity formed by disintegrated tissue.