Updated ACVIM consensus statement on Leptospirosis in Dogs Flashcards
What is leptospirosis caused by?
A spirochete Leptospira, which is a zoonotic bacterial pathogen that effects a wide range of mammals.
How is leptospira transmitted?
Occurs when mucous membranes or abraded skin are exposed to pathogenic strains that are shed from the renal tubules of infected reservoir hosts. These hosts can contaminate soil and remains viable in the environment for weeks to months, they can replicate in water statuated soil.
What are the reservoir hosts of Leptospira?
Rodents especially rats.
How do spirochetes persist in the environment and renal tubles?
The form biofilms.
What region is leptospiraosis most prevalent?
Regions with higher rainfall and warm climates.
Which dog are most at risk of leptospirosis?
All dogs are at risk of leptospirosis, regardless of signalment, geographic location, lifestyle, and the time of year.
How does leptospira evade the innate immune system?
Utilizing corkscrew motion, leptospira efficiently invades host tissues at gel-liquid borders such as vascular walls, emigrating from the vascular space by binding to vascular endothelial cadherin and weakening endothelial cell barriers.
Describe the pathophysiology of liver dysfunction in leptospirosis.
Liver dysfunction results from disruption of hepatocyte intercellular junctions by spirochetes, with leakage of bile into the circulation which is reflected biochemically as a cholestatic hepatopathy.
What are the clinical manifestations of leptospirosis?
- Acute kidney injury (tubulointerstital nephritis)
- Cholestatic hepatopathy
- Leptospiral pulmonary haemorrhage syndrome
- Coagulopathy
- Vascultitis
- Pancreatitis
- Ocular involvement
- Myocarditis
- Myositis
- Abortion or infertility
- Calcinosis cutis
What biochemistry/urinary changes would you expect with acute kidney injury caused by leptospirosis?
- Azotaemia
- Electrolyte abnormalities including, hyperkalemia, hypokalemia, hyponatremia, and hypochloremia
- Isosthenuria
- Glucouria
- Cylindruria
- Proteinuria
- Pyuria
What biochemical changes would you expect with a cholestatic hepatopathy
Increased ALP > ALT and AST.
Hyperbilirubinaemia
Hypoalbuminaemia
What lung pattern would you expect with leptospiral pulmonary haemorrhage syndrome?
Diffuse or patchy interstitial to alveolar pattern
What CBC and biochemical changes would you expect with a coagulopathy?
- Anaemia
- Hypoalbuminaemia/Hypoproteinaemia
- Thrombocytopaenia
- Hyperfibrinogenemia
- Prolonged PT/APTT
What can commonly occur secondary to vasculitis?
Pleural effusion, mild ascites / retroperitoneal effusion.
What biochemical changes would you expect with pancreatitis?
- Increase liver enzymes
- Hyperbilirubinaemia
- Increased canine pancreatic lipase activity
- Increased DGGR lipase
What biochemical changes would you expect with myocarditis?
Increased serum troponin
What biochemical changes would you expect with myositis?
Increased CK
What can tubulointerstitial nephritis in leptospira infection in dgos progress to?
Can progress to renal fibrosis as once the adaptive immune is mounted leptospirosis can persist as a biofil in the eye or the renal tubules.
What are the most common CBC findings in leptospirosis?
- Neutrophilia with left shift
- Lymphopaenia
- Monocytosis
- Thrombocytopaenia
- Mild to moderate, non-regenerative anaemia
