Lymph Node - Congestion

Lymph node - Congestion in a female B6C3F1/N mouse from a chronic study. Numerous vessels are expanded by an excessive accumulation of blood (arrows).
Figure 1 of 2
comment:
Congestion of blood vessels (e.g., capillaries or venules) may be seen in lymph nodes of rodents, particularly associated with angiectasis ( Figure 1

recommendation:
When lymph node congestion is believed to be associated with treatment, it should be diagnosed and graded. If lymph node congestion is secondary to another lesion (e.g., angiectasis or neoplasia) or believed to be the result of euthanasia, necropsy, or the manner in which the animal died, it should not be diagnosed but may be described in the pathology narrative.references:
Elmore SA. 2006. Histopathology of the lymph nodes. Toxicol Pathol 34:425-454. Full Text: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC1892634/
National Toxicology Program 2010. NTP TR-555. Toxicology and Carcinogenesis Studies of 1,2-Dibromo-2,4-Dicyanobutane (CAS No. 35691-65-7) in F344/N Rats and B6C3F1 Mice (Dermal Studies). NTP, Research Triangle Park, NC. Abstract: https://ntp.niehs.nih.gov/go/32614
Web page last updated on: January 27, 2015