| Description |
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The hallmark of all foreign-body reactions is the phagocytosis or attempted phagocytosis of the foreign material.
The initial congregation of phagocytic cells at the site of implanted foreign material is facilitated by the vasodilatation, preferential vascular shunting, and local edema which accompany any inflammatory reaction.
When the foreign material is of microbial dimensions, it is easily disposed of. With larger, and especially insoluble, foreign material, the phagocytic cells fuse to form foreign-body giant cells which surround the offending agent.
If the foreign body is of macroscopic size, these giant cells may be unsuccessful in their attempt to engulf it and the chronic inflammatory process will continue as long as the inciting matter remains.
A foreign-body granuloma is a chronic or persistent inflammation caused by foreign material which the body is unable to remove by phagocytosis. The inciting foreign material may be truly foreign, such as starch or talc, or it may be a product of the body that is considered by the immune system to be foreign, such as keratin, hair, or cholesterol. |
