Respiratory System

Nose, Epithelium - Fibrosis

Narrative
Comment:

Fibrosis appears microscopically as an increase in the amount of fibrous connective tissue that either replaces or expands normal structures. Because it is often a response to severe tissue damage, fibrosis is often associated with inflammation and/or necrosis. Fibrosis in the lamina propria of the nose (Figure 1; compare with control shown in Figure 2) is uncommon.

Recommendations:
Fibrosis is an uncommon lesion in the nasal cavity and should be diagnosed and assigned a severity grade whenever it is observed. As with inflammation, the epithelial cell type associated with the fibrosis should be recorded as a site modifier. Other lesions, such as the inflammation and hyperplasia noted above, should be diagnosed separately.
References:

References not listed.

  • Image of fibrosis in the nose, transitional epithelium from a female B6C3F1/N mouse in a chronic study

    Nose, Transitional epithelium - Fibrosis in a female B6C3F1/N mouse from a chronic study. Eosinophilic fibrillar material expands the lamina propria, separating the epithelium from the glands in the lamina propria.

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<p>Nose, Transitional epithelium - Fibrosis in a female B6C3F1/N mouse from a chronic study. Eosinophilic fibrillar material expands the lamina propria, separating the epithelium from the glands in the lamina propria.</p>

Nose, Transitional epithelium - Fibrosis in a female B6C3F1/N mouse from a chronic study. Eosinophilic fibrillar material expands the lamina propria, separating the epithelium from the glands in the lamina propria.
<p>Nose, Transitional epithelium - Normal in a male B6C3F1/N mouse from a chronic study. This normal lateral wall in the nose is presented for comparison with Figure 2. A tooth (asterisk) is visible in the section.</p>

Nose, Transitional epithelium - Normal in a male B6C3F1/N mouse from a chronic study. This normal lateral wall in the nose is presented for comparison with Figure 2. A tooth (asterisk) is visible in the section.

Authors

Rodney A. Miller, DVM, PhD, DACVP
NC Pathology Group Manager
Senior Pathologist
Experimental Pathology Laboratories, Inc.
Research Triangle Park, NC

Mark F. Cesta, DVM, PhD, DACVP
Staff Scientist, NTP Pathologist
Cellular and Molecular Pathology Branch
Division of the National Toxicology Program
National Institute of Environmental Health Sciences
Research Triangle Park, NC

Reviewers

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

Ronald Herbert, DVM, PhD
NTP Pathologist
Group Leader, Pathology Support Group
Division of the National Toxicology Program
National Institute of Environmental Health Sciences
Research Triangle Park, NC