Oleogranulema

Oleogranulomas are common lesions that occur in the setting of cystic acneiform lesions or in areas where there is an inflammatory response to trauma. Oleogranulems are inflammatory nodules that contain eosinophils and numerous lipid drops similar to those seen in biopsy sections of adult acneiform disease. These lesions typically have a sterile center surrounded by a dense inflammatory rim. The lipid center of the oleogranular appears to consist primarily of cholesterol esters. The inflammatory reaction in the center appears to be centered around T cells and mononuclear mast cells. These processes are likely related to the secretion of immunoglobulin and the appearance of tryptase-positive cells.

Oleogranulae appear within days of the trauma and sometimes become associated with scarring. They almost always resolve without residual effects, and are often found in instances such as frostbite and burn injuries. They may be seen following a burst boil caused by folliculitis or other forms of severe facial acne.