Leptospirosis - Cats and Dogs

    • Dogs and cats
      • Serovars canicola and icterohaemorrhagica cause leptospirosis in dogs, but are vaccinated against
      • Serovars pomona and grippotyphosa are becoming important
      • The host-adapted serovar canicolar causes acute renal failure in puppies; a chronic uraemic syndrome may follow
      • Incidental infections with serovar icterohaemorrhagica or copenhagenii cause renal failure
      • L. icterohaemorrhagiae may cause hepatic jaundice
      • Serovar bratislava causes abortion and infertility in dogs, which may be the maintenance host
      • Infections uncommon in cats


  • Leptospirosis icterohaemorrhagica - a septicaemic disease which affects the liver
  • puppies
  • Leptospirosis is an important spirochaetal group of diseases causing disease in animals and humans (zoonotic)
  • Transmission
    • via urine of affected animals
    • organisms can remain viable for weeks in damp conditions
  • method of action
    • cause anaemia via intravascular haemolysis
Clinical
  • fever
  • dehydration
  • haemorrhaging from the mucous membranes of the body
Diagnosis
  • dark field microscopy on fresh urine is best
Gross
  • widespread hameorrhages
  • icterus
  • pale foci in the liver (not always a constant finding)
  • subcapsular and cortical renal haemorrhages
Microscopically
  • foci of necrosis
  • dissociation of hepatocytes form each other (similar to post mortem change)
  • substantial haemosiderin in the Kuppfer cells (from the haemolysis)
  • need to use a silver stain or immunofluorescence to demonstrate the organisms in tissues