Leptospirosis is a contagious zoonotic disease that may result in chronic liver and kidney disease and death. The organism Leptospires thrives in water. The species ‘Leptospira interogans is a bacterial pathogenic affecting both animals and humans. The strains causing Leptospirosis in dogs include L. Icterohaemorrhagiae and L. Canicola. Preventative vaccinations and wildlife migrations can affect the control of the disease’s presence.
Transmission may occur during times of flooding with wet soil conditions and moderate temperatures during spring and winter or in crowded kennels. The organism passes in infected urine or urine-contaminated water, food and bedding. The canine acts as a maintenance host that carries most or the organism’s life cycle. The organism penetrates the mucous membranes of eyes, bitten or scraped skin. Ingesting flesh of infected animals is another source of transmission.
The bacterium multiplies in the blood vascular space and affects the kidney, liver spleen, central nervous system (CNS), eyes and genital tract. Kidneys are the breeding grounds for this strain. As this strain is shed in the urine for weeks to months, other dogs and humans may be exposed and the infectious cycle continues.
Symptoms and Diagnosis
Symptoms of Leptospirosis may vary according to the host’s age and immunity, as well as environmental factors affecting bacteria and the strain’s virulent. This disease afflicts young animals more severely than adult counterparts.
During the first four to twelve days after infection, the dog may suffer from fever (103-105°F), decreased appetite, vomiting, pain, or conjunctivitis. Other symptoms that may occur include a drop in body temperature, shivering, muscle tenderness, or increased thirst. The urine color may range from lemon to deep orange. Frequent urination and resulting dehydration may indicate an invasion of kidney tubule cells..
In advanced cases, symptoms include depression, breathing difficulties, muscular tremors, and bloody vomitus and feces. The infection invades the liver and gastrointestinal system. Most affected canines will experience renal failure brought on by serovar grippotyphosa and pomona.
Some chronically infected canines that show no clinical symptoms may shed bacteria in their urine for months or years.
Diagnosis may be from a combination of symptoms and lab and serologic tests, such Microscopic Agglutination Test (MAT), ELISA and MCAT. Testing of blood chemistry and urine can determine abnormalities of blood components, elevation of liver enzymes, electrolyte imbalances and active urinary sediments. These findings are consistent with Leptospira infections and the associated vascular, liver and kidney diseases.
Treatment of Leptospirosis may include antibiotics, fluid replacement and control of vomiting and kidney or liver infections. Antibodies may shorten the duration, cut the time for risks of contagion and decrease the severity of liver and kidney damage. Initial treatment with antibiotics includes penicillin, derivatives, or doxycycline. Tetracyclines, fluroquinolones and erythromycin may eliminate the carrier state. To reverse kidney failure, supportive therapy can restore urine production, kidney filtration and blood flow. For severe liver disease that may result in bleeding disorders, a transfusion may be in order.
Special precautions can help reduce the risk of contagion to humans and other animals. Infected canines can be quarantined. Blood, urine and tissues are biologically hazardous waste. Infected areas should be washed and disinfected.
Long-term outcomes may include patient survival rate as high as 80-90%, chronic renal failure, and chronic active hepatitis.