2. Definition
It is peracute, acute or chronic water born contagious
disease of dogs caused by leptospira interrogans spp.,
characterized by pyrexia, anorexia, depression and signs
of renal and hepatic failure
3. Etiology
Leptospira interrogans servoars as:
L. Icterohaemorrhagica
L. Conicola
L. Grippotyphosa
All serovars are antigenically distinct
It is flexible filamentous, motile spirochete
Infected dogs may excrete leptospira in urine intermittently for
months or even years
4. Epidemiology
Distribution
The disease is worldwide and present in Egypt
Animal susceptibility
Dogs of all ages are susceptible but cats appears to be resistant
Mode of transmissions
Source of infection
Clinically infected or carrier dogs shed the organisms in urine for months or
even years
Mode of transmission
Direct contact through penetration of mucosa of mouth or conjunctiva or
abraded skin
Ingestion of contaminated materials as infected meats
Indirect transmission through exposure to contaminated fomites
Transplacental or venereal and bite wound transmission
5. Pathogenesis
After infection
Organism Localized and replicate in
Kidney and liver
Replicate in nephron cause nephritis
and renal damage and shedding in
urine for long time
Injury and damage to hepatocytes in liver
causing hepatic fibrosis
The organism cause meningitis, Uveitis and transplacental
infection cause abortion
6. Clinical signs
IP 1-2 w, morbidity rate is variable and mortality rate is low
Peracute
fever, depression and anorexia
Abdominal and renal pain and reluctance to move
Vascular injury with hematemesis, melena, epistaxis and petechiation
Terminally, hypothermia, shock and death
7. Subacute and chronic form
Fever, depression, anorexia, abdominal pain and vomition
Paraspinal hyperesthia due to muscular, meningeal and renal
inflammation
Peticheal and echymotic hemorrhage
Deterioration in renal function as anuria or oliguria and frequent
urination
Uremic breath due to chronic nephritis
Scanty feces with melena
Signs of hepatitis as change of fecal color from brown to gray and
icterus
Occasionally, abortion, uveitis and meningitis may be occur
8. Postmortem lesions
Carcass show icteric mm with diffuse petechiation
Respiratory tract is edematous and lung is congested
Liver is enlarged with yellow brown discoloration
Kidney is enlarged, pale or yellow in color and have subcapsular
hemorrhage
Swelling and focal white spotting in renal cortex
10. Diagnosis
Laboratory diagnosis
Samples:
Urine, Kidney and liver from recently dead animal, blood and serum
Laboratory procedures
1. Demonstration of organism by dark field microscope
2. Urine anlanysis, proteinuria, hyperbilurinuria
3. Hematological examination, leukopenia then leukocytosis and
thrombocytopenia
4. Serological test as agglutination test or ELISA
5. Culture is difficult because of the organism is fastidious and slow
growth
11. Differential diagnosis
The disease misdiagnosed with diseases cause hepatic or renal
damage as:
1. Infectious hepatitis
2. Canine disptemper
12. Treatment
Specific antibiotic
Penecillin G sodium 25.000- 40.000 IU/kg I/V or I/M
Dihyderostreptomycin 15 mg/kg IM every 12 hr
Supportive treatment
Fluid therapy, tonics
Diuretic as furosemide
13. Control
Management
Isolation and treated the infected animal
Hygienic disposal of infected materials
Detection and elimination od carriers and all known shedders
Prevent contact between dogs and their urine
Cleaning and disinfectant all infected premises
Vaccination
Bivalent leptospira bacterin (L. canicola & L. icterohaemorrhagica)
It gives at 9, 12 and 15 week of age
Repeated annually
The immunization reduce severity and incidence of the disease but
it does not prevent the carrier
