Skin - Inflammation











comment:
In dermal application toxicity/carcinogenicity studies, inflammation is one of the most common responses to chemicals. Inflammation may be nonspecific or related to trauma from self-mutilation (scratching), contact with edges of equipment, arthropod parasitism, or wounds from fighting. Secondary inflammation can also be associated with cutaneous neoplasms.Acute inflammation ( Figure 1












All forms of inflammation may be accompanied by associated lesions, including edema (though this is more commonly associated with acute inflammation), epithelial hyperplasia, hyperkeratosis, neovascularization, or hemorrhage with or without hemosiderin-containing macrophages.
recommendation:
Whenever present, the specific type of inflammation should be recorded and assigned a severity grade. When present as a secondary finding associated with neoplasia, fat necrosis or epithelial necrosis, or epithelial or other types of cysts, inflammation need not be diagnosed separately but should be described in the pathology narrative. When secondary findings such as edema, hemorrhage, or osseous metaplasia are present, they need not be diagnosed but should be described in the narrative. If the inflammation is accompanied by epithelial hyperplasia, hyperkeratosis, or excessive fibrosis, such findings should be diagnosed and graded independently of chronic inflammation. When granulomatous inflammation is accompanied by foreign material, both diagnoses should be documented separately, but the diagnosis of foreign material should not be graded.references:
Elwell MR, Stedman MA, Kovatch RM. 1990. Skin and subcutis. In: Pathology of the Fischer Rat: Reference and Atlas (Boorman GA, Eustis SL, Elwell MR, Montgomery CA, MacKenzie WF, eds). Academic Press, San Diego, 261-277. Abstract: https://www.ncbi.nlm.nih.gov/nlmcatalog/9002563
Klein-Szanto AJP, Conti CJ. 2002. Skin and oral mucosa. In: Handbook of Toxicologic Pathology, 2nd ed (Haschek WM, Rousseaux CG, Wallig MA, eds). Academic Press, San Diego, 2:85-116. Abstract: http://www.sciencedirect.com/science/book/9780123302151
Peckham JC, Heider K. 1999. Skin and subcutis. In: Pathology of the Mouse: Reference and Atlas (Maronpot RR, Boorman GA, Gaul BW, eds). Cache River Press, Vienna, IL, 555-612. Abstract: http://www.cacheriverpress.com/books/pathmouse.htm
Web page last updated on: January 15, 2014