JPC SYSTEMIC PATHOLOGY

INTEGUMENTARY SYSTEM

November 2016

I-V14

 

Signalment (JPC Accession #1497357):  California sea lion (Zalophus californianus)

HISTORY:  This sea lion presented with multiple vesicular and ulcerated skin lesions over various parts of the body.

HISTOPATHOLOGIC DESCRIPTION:  Haired skin:  There are multifocal intracorneal vesicopustules, up to 3 mm in diameter, filled with degenerate and non-degenerate neutrophils, cellular and karyorrhectic necrotic debris, fibrin and granular to amorphous, eosinophilic proteinaceous fluid. The epidermis is hyperplastic with acanthosis, prominent rete ridges, orthokeratotic hyperkeratosis, pigment in all layers (hyperpigmentation), and moderate spongiosis (intercellular edema).  Within the superficial dermis, there are low numbers of perivascular lymphocytes, plasma cells, and macrophages. Lymphatics are mildly dilated (edema), and the endothelium of superficial small vessels is reactive.

HISTOPATHOLOGIC DESCRIPTION:  Haired skin, pinna:  There is a focally extensive 1.5 cm diameter ruptured, ulcerated vesicle with replacement of the epidermis by a serocellular crust of fibrin, necrotic debris, degenerate neutrophils, macrophages, lymphocytes, and plasma cells.  The epithelium adjacent to the ulcer is hyperplastic with spongiosis and moderate orthokeratotic hyperkeratosis, and is undermined forming 2 overhanging flaps. The underlying dermis contains low numbers of previously described inflammatory cells, granulation tissue (characterized by numerous small caliber vessels that are oriented perpendicular to the ulcer) and edema (characterized by clear space between dermal collagen and ectatic lymphatics).

MORPHOLOGIC DIAGNOSIS:  1. Haired skin:  Dermatitis, vesiculopustular, subacute, multifocal, mild, with orthokeratotic hyperkeratosis, California sea lion (Zalophus califonianus), pinniped. 

  1. Haired skin, pinna: Dermatitis, ulcerative, subacute, focally extensive, mild, with orthokeratotic hyperkeratosis.

ETIOLOGY:  San Miguel sea lion virus (SMSV) (calicivirus)

ETIOLOGIC DIAGNOSIS:  Caliciviral dermatitis

GENERAL: 

PATHOGENESIS: 

TYPICAL CLINICAL FINDINGS: 

TYPICAL GROSS FINDINGS: 

TYPICAL MICROSCOPIC FINDINGS: 

ULTRASTRUCTURE: 

ADDITIONAL DIAGNOSTIC TESTS: 

DIFFERENTIAL DIAGNOSIS:

COMPARATIVE PATHOLOGY:

Caliciviridae viruses:

REFERENCES: 

  1. Barthold SW, Griffey SM, Percy DH. Pathology of Laboratory Rodents and Rabbits. 4th ed. Ames, IA: Wiley Blackwell; 2016: 264-6.
  2. Cameron R. Diseases of the skin. In: Straw BE, D'Allaire S, Zimmerman JJ, D’Allaire S, Taylor DJ, eds. Diseases of Swine. 9th ed. Ames, IA: Iowa State University Press; 2006: 328.
  3. Chen R, Neill JD, Noel JS, Gutson AM, Glass RI, Estes MK, Venkataram Prasad BV. Inter- and intragenus structural variations in caliciviruses and their functional applications. J of Virol. 2004; 78(12):6469-6479.
  4. Cheville NF. Cytopathology of viral diseases. In: Cheville NF, ed. Ultrastructural Pathology: The Comparative Cellular Basis of Disease. 2nd ed. Ames, IA: Wiley-Blackwell; 2009: 399-401.
  5. Gaskell R, Dawson S, Radford A. Feline respiratory disease. In: Greene CE, ed. Infectious Diseases of the Dog and Cat. 4th ed. Louis Missouri: Elsevier Saunders; 2012:151-152.
  6. Hsu CC, Piotrowski SL, Meeker SM, Smith KD, Maggio-Price L, Treuting PM. Histologic lesions induced by murine norovirus infection in laboratory mice. Vet Pathol. 2016; 53(4): 754-63.
  7. Lenghaus C, Studdert MJ, Gavier-Widen D. Calicivirus infections. In: Williams ES, Barker IK, eds. Infectious Diseases of Wild Mammals. 3rd ed. Ames, IA: Iowa State University Press; 2001: 286-289.
  8. Miller RE, Fowler ME. Fowler’s Zoo and Wild Animal Medicine. Vol. 8. St. Louis, MO; Elsevier Saunders: 2015: 446.
  9. MĪ‹ller G, Gröters S, Siebert U, Rosenberger T, Driver J, König M, Becher P, et al. Parapoxvirus infection in harbor seals (Phoca vitulina) from the German North Sea. Vet Pathol. 2003; (40)4:445-54.
  10. Murphy FA, Gibbs, EPJ, Horzinek MC, Studdert MJ. Caliciviridae. In: Veterinary Virology. 3rd ed. San Diego, CA: Academic Press; 1999: 540.
  11. Smith AW, Skilling DE, Matson DO, Kroeker AD, Stein DA, Berke T, Iversen PL. Detection of vesicular exanthema of swine-like calicivirus in tissues from a naturally infected spontaneous aborted bovine fetus. J Am Vet Med Assoc. 2002; 220(4):455-458.
  12. 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. St. Louis, MO: Elsevier; 2016: 121.
  13. Van Bonn W, Jensen ED, House C, House JA, Burrage T, Gregg DA. Epizootic vesicular disease in captive California sea lions. J Wildl Dis. 2000; 36:500-507.


Click the slide to view.



Click on image for diagnostic series.



Back | Home | Contact Us | Links | Help |