Leptospirosis Guidelines

Question 1

How susceptible are cats to Lepto?

Answer 1

very resistant to clinical infection but up to 20% of outdoor cats may be carriers

Question 2

How does Lepto cause endothelial damage?

Answer 2

lepto organisms corkscrew through the endothelium causing holes and increasing permeability

Question 3

List organs affected by Lepto and how they are affected

Answer 3

kidneys - glomerulonephritis
liver - cholestatic hepatopathy, disruption of hepatocyte intercellular junctions - bile leakage
brain - aseptic meningitis
pancreas - may develop pancreatitis
GI tract - gastroenteritis
Platelets - leptospires –> direct cytotoxic platelet damage
lung- leptospiral pulmonary hemorrhage, endothelial damage may be contributing

Question 4

What 2 organs does Lepto persist in after it is cleared from the blood?

Answer 4

eyes
kidneys

Question 5

In an lepto-unvaccinated dog with acute onset febrile illness, what test should be recommended?

Is empirical treatment recommended in these cases?

Answer 5

NAAT

yes, 7 days of doxy could be considered, but more evidence needed for better antibiotic stewardship

Question 6

What are the most common CBC findings in dogs with lepto?

Answer 6

neutrophilia with increased bands, lymphopenia, monocytosis
mild to moderate, non-regenerative anemia
thrombocytopenia

Question 7

What are usual chem/lyte changes in dogs with lepto?

Answer 7

elevated SDMA and creatinine
ALP elevated, to less extend: ALT, AST, also hyperbilirubinemia

depending on extend of kidney disease: hypo/hyperkalemia, hyponatremia, hypochloremia

elevated lipase, amylase

elevated CK

Question 8

What is the evidence of heart disease in lepto?

Answer 8

elevated troponin-I cc - but has also been reported in non-lepto AKIs so may be indirect complication of AKI rather than lepto

Question 9

What is the suspected cause for the increse of lipase and amylase in lepto?

Answer 9

decreased renal excretion or other GI disease considered before making conclusion on pancreatitis

Question 10

What are typical UA findings in lepto?

Answer 10

• proteinuria (usually UPC < 5 through)
• cylinduria
• isosthenuria/hyposthenuria
• glucosuria

Question 11

What are the 2 types of proteinuria seen in Lepto?

Answer 11

tubular - defective tubular reabsorption of low molecular weight proteins
glomerular - high molecular weight proteins

Question 12

What are commonly observed Coag profile and teg changes in lepto dogs?

Answer 12

thrombocytopenia
elevated PT and aPTT
hyperfibrinogenemia (more common) and hypofibrinogenemia
low antithrombin %
increased D-dimers
teg: 20% hypocoagulable, 40% hypercoagulable

Question 13

How does MAT work. What are its limitations and advantages?

Answer 13

MAT: tests serum for antibodies against usually 6-7 serovar of leptospirosis
titer established
ideally 2 titers: acute and convalescent titers (7-14 days apart)

single positive titer lacks specificity - previous vaccine or exposure - vaccine may increase titers for 4 months to a year

Question 14

What is the method of point-of-care serologic tests?
Which type of antibodies does the WITNESS letpo rapid test detect?

Answer 14

later flow technology

SNAP (IDEXX) or WITNESS (Zoetis)

witness –> IgM

Question 15

How specific is a positive WITNESS test in an unvaccinated dog with CS consistent with lepto?

Answer 15

> 97%

Question 16

What type of samples should be obtained when to submit for NAAT? How does the sensitivity and specificity of each of these samples compare? Which of these samples is confirmatory if positive?

Answer 16

blood (without heparin, e.g., EDTA) and urine

blood more specific, urine more sensitive but less specific (positive in up to 20% in apparently healthy dogs)

negative sample with either does not r/o lepto

blood is confirmatory if positive

Question 17

How do vaccinations affect NAAT testing for lepto?

Answer 17

do not affect them

Question 18

What are Lepto cultures most important for?

Answer 18

for surveillance - assessing what species are present in a region

Question 19

What are the requirements to say a case probably has lepto versus confirming it has lepto?

Answer 19

probably: clinical criteria met and at least one supportive diagnostic test

confirmed: clinical criteria met and at least one confirmatory diagnostic test

Question 20

What are the clinical criteria for lepto?

Answer 20

• acute systemic disease within past 2 weeks (e.g., fever, lethargy, PU/PD, anorexia)

plus at least 2 of the following:
* neutrphilic leukocytosis
* thrombocytopenia
* evidence of AKI
* cholestatic hepatopathy on blood work
* blood work evidence for pancreaitits
* elevated CK
* glucosuria
* active urine sediment
* xray findings consistent with pulmonary hemorrhage syndrome
* US findings including pancreatitis, hyperechoic renal cortices, or perirenal fluid
* cardiac arrhythmias on ECG or elevated troponin

Question 21

What are the supportive laboratory criteria for Lepto diagnosis?

Answer 21

• single positive titer on MAT
• single positive IGM titer (POC)
• positive on darkfield microscopy
• urine NAAT positive

Question 22

What are the confirmatory laboriatory criteria for the lepto diagnosis?

Answer 22

• 4 fold increase from acute and convalescent titer
• positive blood NAAT
• positive culture

Question 23

What is the antibiotic therapy recommendation for leptospirosis?

Answer 23

• doxycycline - if eating, 2 weeks
• if vomiting or other adverse reactions - ampicillin IV, amoxicillin IV, or penicillin G IV

Question 24

What is the recommended diet for patients suffering from leptospirosis?

Answer 24

normal high quality protein
avoid kidney diet - is high in fat and could worsen pancreatitis, no evidence that protein has to be restricted in acute kidney disease from lepto

Question 25

What is the recommendation for liver protectants and ursodiol in lepto?

Answer 25

not recommended, lack of evidence

Question 26

When is referral of Lepto patients to a facility providing extracorporeal therapy recommended?

Answer 26

if AKI IRIS stage 4 or serum creatinine > 5 mg/dL

Question 27

What are negative prognostic factors for leptospirosis in dogs?

Answer 27

hyperbilirubinemia
hypocoagulability

Question 28

What is the cutoff score to predict non-survival in the Sege’s model C for dogs with AKI with lepto managed with extracorporeal therapy?

Answer 28

19.9

Question 29

How soon after infection does leptospiruria commence?

Answer 29

7-10 days

Question 30

For how long after starting doxycycline treatment should owners wear gloves at home, avoid contact to their dog’s urine, and wear eye protection when cleaning urine?

Answer 30

48 hours