JPC SYSTEMIC PATHOLOGY

RESPIRATORY SYSTEM

September 2014

P-B05

 

Signalment (JPC# 1947706):  Adult female Long-Evans rat

HISTORY:  This rat had recently whelped.  The dam and pups appeared healthy until five days after whelping, at which time the dam became lethargic, ataxic, dyspneic, and would not nurse her pups.

HISTOPATHOLOGIC DESCRIPTION:  Lung:  Affecting 50% of the section, there are multifocal to coalescing randomly distributed areas of necrosis composed of numerous viable and degenerate neutrophils with fewer macrophages admixed with abundant karyorrhectic and eosinophilic cellular debris and small amounts of hemorrhage.  Necrotic foci are surrounded by many macrophages and fewer reactive fibroblasts and centrally contain large (up to 200 um diameter) colonies of 2 um diameter bacilli.  In less affected areas, the perivascular interstitium and alveolar septa are infiltrated and expanded by variable numbers of macrophages, neutrophils, and lymphocytes.  Alveoli are often filled with proteinaceous fluid (edema), as well as few neutrophils and macrophages.  The pleura is mildly expanded by edema and occasional macrophages and neutrophils and is frequently lined by reactive mesothelium.

MORPHOLOGIC DIAGNOSIS:  Lung:  Pneumonia, embolic, necrosuppurative, multifocal to coalescing, marked, with numerous large colonies of bacilli, etiology consistent with Corynebacterium kutscheri, Long-Evans rat, rodent.

ETIOLOGIC DIAGNOSIS:  Corynebacterial pneumonia

CAUSE:  Corynebacterium kutscheri

CONDITION:  Corynebacteriosis

SYNONYMS:  Pseudotuberculosis

GENERAL DISCUSSION: 

PATHOGENESIS: 

TYPICAL CLINICAL FINDINGS: 

TYPICAL GROSS FINDINGS: 

TYPICAL LIGHT MICROSCOPIC FINDINGS: 

ADDITIONAL DIAGNOSTIC TESTS: 

DIFFERENTIAL DIAGNOSIS: 

COMPARATIVE PATHOLOGY: 

REFERENCES: 

  1. Barthold SW, Griffey SM, Percy DH. Pathology of Laboratory Rodents and Rabbits. 4th ed. Ames, IA: Blackwell Publishing; 2016: 69, 140-141, 185, 225.
  2. Jeong E, Young-Suk W, Hyoung-Chin K, Myung-Hawn C, Yang-Kyu C. Role of IL-10 deficiency in pneumonia induced by Corynebacterium kutscheri in mice. J Microbiol Biotechnol. 2009;19(4):424-430.
  3. Jones TC, Hunt RD, King NW. Veterinary Pathology. 6th ed. Baltimore: Williams and Wilkins; 1997:479-481.
  4. Maronpot RR, Boorman GA, Gaul BW. Pathology of the Mouse.  Vienna, IL: Cache River Press; 1999: 302.
  5. Won YS, Jeong ES, Park HJ, et al. Upregulation of galectin-3 by Corynebacterium kutscheri infection in the rat lung. Exp Anim. 2007;56(2):85-91.


Click the slide to view.



Click on image for diagnostic series.



Back | Home | Contact Us | Links | Help |