JPC SYSTEMIC PATHOLOGY
DIGESTIVE SYSTEM
August 2018
D-B01

 

Signalment (JPC #1104736):  Guinea pig  

HISTORY:  None

HISTOPATHOLOGIC DESCRIPTION:  Liver:  Affecting approximately 10% of the hepatic parenchyma are multifocal, random, variably sized necrotic foci characterized often by both coagulative and lytic necrosis, with retention of cellular architecture with loss of differential staining or eosinophilic cellular and karyorrhectic debris, respectively. Necrotic foci are surrounded and infiltrated by neutrophils, lymphocytes, and macrophages (paratyphoid nodules) and contain variable amounts of fibrin and hemorrhage.  Hepatocytes adjacent to necrotic foci are often swollen with pale, vacuolated cytoplasm (degeneration).  Periportal connective tissue is multifocally infiltrated by low to moderate numbers of lymphocytes, plasma cells, fewer neutrophils, and macrophages.  There is a mild increase in the number of biliary ductular profiles (ductular reaction) and lymphatics are multifocally ectatic  Remaining hepatocytes are expanded by one to few clear cytoplasmic vacuoles up to 12um in diameter that displace the nucleus (vacuolar change, lipid-type).  Multifocally the capsule is irregular and expanded up to two times normal by variable numbers of neutrophils, lymphocytes, plasma cells, and macrophages. 

MORPHOLOGIC DIAGNOSIS: 

  1. Liver:  Hepatitis, necrotizing, neutrophilic and lymphohistiocytic, multifocal, random, moderate, guinea pig (Cavia porcellus), rodent
  2. Liver: Periportal infiltrates, lymphoplasmacytic, multifocal, mild, with mild ductular reaction and moderate lipid-type vacuolar change.

ETIOLOGIC DIAGNOSIS:  Hepatic salmonellosis

CAUSE:  Salmonella Enteritidis

GENERAL DISCUSSION: 

PATHOGENESIS: 

TYPICAL CLINICAL FINDINGS:

TYPICAL GROSS FINDINGS: 

Forms Serovar Clinical presentation Histopathology

Peracute

Calves, foal, pigs; young animals at greater risk

 

Most commonly S. Cholerasuis

 

Polyserositis, cyanosis (pigs), DIC, toxin production, green feces (foals), death attributable to DIC

 

Fibrinoid vasculitis/vascular necrosis, thrombosis

Acute Enteric

Cattle, pigs, horses

(rarely carnivores)

Most commonly S. Typhimurium

 

Diffuse catarrhal enteritis, diffuse fibrinonecrotic ileotyphlocolitis, septic tank odor to feces, fibrinous cholecystitis is pathognomonic for acute enteric salmonellosis in calves

Characteristic paratyphoid nodules (multiple foci of hepatocellular necrosis with Kupffer cell hyperplasia)

 

Chronic

Cattle, pigs, horses

Any

Typically seen in pigs: button ulcers (discrete foci of necrosis in colon and cecum), rectal strictures due to poor/no collateral vascular supply of the pig rectum

Vascular thrombosis, toxins,

TYPICAL LIGHT MICROSCOPIC FINDINGS: 

ADDITIONAL DIAGNOSTIC TESTS: 

DIFFERENTIAL DIAGNOSIS:

Hepatic necrosis in a guinea pig:

COMPARATIVE PATHOLOGY: 

Swine:  Salmonellosis is a very important disease of swine.

Horses

Cattle

Sheep

Carnivores

Avian

Laboratory Animals Most commonly S. Typhimurium and S. Enteriditis; disease and outbreaks are rare now but may be common in the pet trade

Nonhuman Primates

Reptiles

REFERENCES: 

  1. Barthold SW, Griffey SM, Percy DH. Pathology of Laboratory Rodents and Rabbits. 4th ed. Ames, IA: Blackwell Publishing; 2016: 58-59, 140, 184-185, 203, 228, 285.
  2. Brady AG, Carville AAL. Digestive system diseases of nonhuman primates.  In: Abee CR, Mansfield K, Tardiff S, Morris T, eds.  Nonhuman Primates in Biomedical Research: Diseases, Vol. 2.  2nd ed.  Waltham, MA: Academic Press; 2012:600-601.
  3. Brown DL, Van Wettere AJV, Cullen JM. Hepatobiliary system and exocrine pancreas. In: Zachary JF, ed. Pathologic Basis of Veterinary Disease. 6th ed. St. Louis, MO: Elsevier; 2017:444, 464.
  4. Clothier KA, Kim P, Mete A, Hill AE. Frequency, serotype distribution, and antimicrobial susceptibility patterns of Salmonella in small poultry flocks in California.  J Vet Diag Invest. 2018;30(3):471-475.
  5. Cullen JM, Stalker MJ. Liver and biliary system.  In: Maxie MG, ed. Jubb, Kennedy and Palmer’s Pathology of Domestic Animals. Vol 2. 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:314-315.
  6. Eckstrand CD, Woods LW, Diab SS, Crossley BM, Giannitti F. Diagnostic exercise: high mortality in a flock of chukar partridge chicks (Alectoris chukar) in California.  Vet Pathol. 2015;52(1):189-192.
  7. Fulton RM. Bacterial diseases.  In: Boulianne M., ed. Avian Disease Manual. 7th Jacksonville, FL: American Association of Avian Pathologists; 2013:122-131.
  8. Gelberg HB. Alimentary system and the peritoneum, omentum, mesentery, and peritoneal vacity. In: Zachary JF, ed. Pathologic Basis of Veterinary Disease. 6th ed. St. Louis, MO: Elsevier; 2017:353, 377-378.
  9. Grandolfo E, Parisi A, Ricci A, et. al. High mortality in foals associated with Salmonella enterica Enterica Abortusequi infection in Italy.  J Vet Diag Invest. 2018;30(3):483-485.
  10. Gyles C, Boerlin P. Horizontally transferred genetic elements and their role in pathogenesis of bacterial disease.  Vet Pathol. 2014;51(2):328-340.
  11. Niwa H, Hobo S, Kinoshita Y, et. al. Aneurysm of the cranial mesenteric artery as a site of carriage of Salmonella enterica enterica serovar Abortusequi in the horse.  J Vet Diag Invest. 2016;28(4):440-444.
  12. Pecoraro HL, Thompson B, Duhamel GE. Histopathology case definition of naturally acquired Salmonella enterica serovar Dublin infection in young Holstein cattle in the northeastern United States. J Vet Diag Invest. 2017;29(6):860-864.
  13. Sakaguchi K, Nevarez JG, Del Piero F. Salmonella enterica Serovar Pomona infection in farmed juvenile American alligators (Alligator mississippiensis).  Vet Pathol. 2017;54(2):316-319.
  14. Simmons J, Gibson S. Bacterial and mycotic diseases of nonhuman primates.  In: Abee CR, Mansfield K, Tardiff S, Morris T, eds.  Nonhuman Primates in Biomedical Research: Diseases, Vol. 2.  2nd ed.  Waltham, MA: Academic Press; 2012:134-136.
  15. Uzal FA, Plattner BL, Hostetter JM. Alimentary system. In: Maxie MG, ed. Jubb, Kennedy and Palmer’s Pathology of Domestic Animals. Vol 2. 6th ed. Philadelphia, PA: Elsevier Saunders; 2016:51, 99-100, 115, 167-176.
  16. Zachary JF. Mechanisms of microbial infections. In: Zachary JF, ed. Pathologic Basis of Veterinary Disease. 6th ed. St. Louis, MO: Elsevier; 2017:159-160.


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