Liver - Fatty Change





comment:
Fatty change can be focal ( Figure 1

















recommendation:
The morphologic appearance of fatty change is distinctive enough to allow its diagnosis in the absence of confirmatory special stains or other procedures. Whenever present, diagnosis of hepatocellular fatty change should be recorded. Since some degree of fatty change may occur in untreated or vehicle controls, severity grading is recommended to document potential treatment-related effects. Because focal fatty change may be spontaneous, the distribution modifier “focal” should be included in the diagnosis when the lesion is focal. When the lesion is diffuse, no distribution modifier should be used (i.e., the lesion is assumed to be diffuse when the distribution is not specified in the diagnosis). The morphologic features of the fatty change (e.g., macrovesicular, microvesicular, or both) should be described in the pathology narrative. Other distinctive features, such as the pattern of distribution, should also be described in the pathology narrative.Fatty change is frequently accompanied by other cytoplasmic alterations, such as glycogen accumulation or depletion, and it can be difficult to distinguish the different types of alterations in cytoplasmic morphology. In those situations, a diagnosis of hepatocyte cytoplasmic vacuolization is appropriate, along with a severity grade, but the morphology of the cytoplasmic changes in the hepatocytes should be thoroughly described in the pathology narrative. The pathology narrative should also include the pathologist’s opinions regarding the contents of the cytoplasmic vacuoles.
related links:
Liver - Tension Lipidosisreferences:
Cattley RC, Popp JA. 2002. Liver. In: Handbook of Toxicologic Pathology (Haschek WM, Rousseaux CG, Wallig MA, eds). Academic Press, San Diego, 2:187-225.
Eustis SL, Boorman GA, Harada T, Popp JA. 1990. Liver. In: Pathology of the Fischer Rat (Boorman GA, Eustis SL, Elwell MR, Montgomery CA, MacKenzie WF, eds). Academic Press, San Diego, 71-94.
Evans JG, Lake BG. 1998. The digestive system II. Hepatobiliary system. In: Target Organ Pathology (Turton J, Hooson J, eds). Taylor and Francis, London, 61-98.
Greaves P. 2007. Histopathology of Preclinical Toxicity Studies: Interpretation and Relevance in Drug Safety Evaluation, 3rd ed. Elsevier, Amsterdam. Abstract: http://www.sciencedirect.com/science/book/9780444527714
Harada T, Enomoto A, Boorman GA, Maronpot RR. 1999. Liver and gallbladder. In: Pathology of the Mouse: Reference and Atlas (Maronpot RR, Boorman GA, Gaul BW, eds). Cache River Press, Vienna, IL, 119-183. Abstract: http://www.cacheriverpress.com/books/pathmouse.htm
Hardisty JF, Brix AE. 2005. Comparative hepatic toxicity: Prechronic/chronic liver toxicity in rodents. Toxicol Pathol 33:35-40. Full Text: http://tpx.sagepub.com/content/33/1/35.full.pdf
Haschek WM, Rousseaux CG, Wallig MA. 2010. Fundamentals of Toxicologic Pathology, 2nd ed. Academic Press, San Diego, 197-235.
Thoolen B, Maronpot RR, Harada T, Nyska A, Rousseaux C, Nolte T, Malarkey D, Kaufmann W, Kutter K, Deschl U, Nakae D, Gregson R, Winlove M, Brix A, Singl B, Belpoggi F, Ward JM. 2010. Hepatobiliary lesion nomenclature and diagnostic criteria for lesions in rats and mice (INHAND). Toxicol Pathol 38:5S-81S. Full Text: http://tpx.sagepub.com/content/38/7_suppl/5S.full
Web page last updated on: June 19, 2014