Hepatobiliary System

Liver - Intrahepatocellular Erythrocytes

Narrative
Comment:
Intrahepatocellular erythrocytes are uncommon and may be seen as a spontaneous change in aging mice. However, in some NTP studies, this change appears to have been exacerbated by treatment. At low magnification, it may be confused with angiectasis; at higher magnification, enlarged hepatocytes are filled and expanded by numerous erythrocytes. Speculation that this change occurs by erythrophagocytosis or emperipolesis has not been confirmed by ultrastructural studies.
Recommendations:
Intrahepatocellular erythrocytes should be documented whenever present, and the pathology narrative should include a description of the extent of the change. Any associated degenerative or other changes in the hepatic parenchyma should be diagnosed separately if warranted by the severity of these lesions; otherwise, they should be mentioned in the pathology narrative.
References:

Barni S, Bernocchi G. 1991. Internalization of erythrocytes into liver parenchymal cells in naturally hibernating frogs (Rana esculenta L.). J Exp Zool 258:143-150.

Abstract: https://www.ncbi.nlm.nih.gov/pubmed/2022945

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

Lee KP. 1983. Peliosis hepatis-like lesion in aging rats. Vet Pathol 20:410-423.

Abstract: https://www.ncbi.nlm.nih.gov/pubmed/6623845

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
  • Image of Intrahepatocellular erythrocytes in the Liver from a Male B6C3F1 Mouse in a 2 year Study

    Intrahepatocellular erythrocytes in a B6C3F1 mouse from a 2-year study (higher magnification of Figure 1).

Enlarge Image
Enlarge All Images
Intrahepatocellular erythrocytes in a B6C3F1 mouse from a 2-year study.
Intrahepatocellular erythrocytes in a B6C3F1 mouse from a 2-year study.
Intrahepatocellular erythrocytes in a B6C3F1 mouse from a 2-year study (higher magnification of Figure 1).
Intrahepatocellular erythrocytes in a B6C3F1 mouse from a 2-year study (higher magnification of Figure 1).

Author

Robert R. Maronpot, DVM, MS, MPH, DACVP, DABT, FIATP
Senior Pathologist
Experimental Pathology Laboratories, Inc.
Research Triangle Park, NC

Reviewers

John Cullen, VMD, PhD, DACVP, FIATP
Anatomic Pathology, Professor
North Carolina State University College of Veterinary Medicine
Raleigh, NC

David E. Malarkey DVM, PhD, DACVP, FIATP
Head, National Toxicology Program Pathology Group
Cellular and Molecular Pathology Branch
Division of the National Toxicology Program
National Institute of Environmental Health Sciences
Research Triangle Park, NC