1. Leptospirosis Feline/Canine Clinical Management
Navies 2011

2. What causes Leptospirosis?
Leptospirosis is caused by a gram negative, spirochete bacteria.

3. Etiology
Leptospirosis is a disease of worldwide significance that infects both animals and humans.
Leptospirosis, a contagious disease affecting both animals and humans. Leptospirosis is spread by infection with a bacterial pathogen called Leptospira. This may result in chronic liver and kidney disease and fatality in dogs.
ZOONOTIC!!!

4. Leptospirosis History
First described by Adolf Weil in 1886 when he reported an "acute infectious disease with enlargement of spleen, jaundice and nephritis".
Leptospira was first observed in 1907 from a post mortem renal tissue slice. In 1908, Inada and Ito first identified it as the causative organism and in 1916 noted its presence in rats.

5. Leptospirosis (Leptospira interrogans sensu lato)
Scientific name of the infecting organism is Leptospira interrogans sensu lato. Within this species there are many different strains (serovars). Of these different strains there are eight that are of importance for dogs and cats.

6. But, who can become diagnosed with Leptospirosis?
These different strains produce different levels and types of disease depending on the animals they infect. While cats can be infected, they rarely show signs of disease.

7. Signalment
The disease is much more of a problem in dogs, people, and livestock. Infection affects multiple organ systems (most to least): kidney, liver, gastrointestinal, hemopoietic (blood & clotting factors), respiratory, and brain.

8. Other Domestic Animals
Leptospira Serovars
Primary Host
Dog
Cat
Human
Other Domestic Animals
Wild Animals
Rat, pig, horse + _
Cow, horse
Mouse, raccoon, opossum, vole, fox, skunk
Autumnalis
Mouse
Cow
Rat, raccoon, opossum
Ictero- haemorrhagiae
Rat
Cow, horse, pig
Mouse, raccoon, opossum, hedgehog, fox, woodchuck, ape, muskrat, skunk, civet
Cow, pig, skunk, opossum
Horse, sheep, goat, rabbit
Mouse, raccoon, hedgehog, wolf, fox, woodchuck, deer
Canicola
Rat, raccoon, hedgehog, armadillo, mongoose, skunk
Bataviae
Dog, rat, mouse
Hedgehog, armadillo, vole, shrew,
Hardjo -
Pig, horse, sheep
Wild bovidae
Grippotyphosa
Vole, raccoon, skunk, opossum
Cow, pig, sheep, goat, rabbit, gerbil
Mouse, rat, fox, squirrel, bobcat, shrew, hedgehog, muskrat, weasel

9. Prevention?
The current canine vaccines protect against the serovars canicola and icterohaemorrhagiae. These two serovars have been decreasing in total number of infections, but unfortunately, other serovars that infect dogs such as grippotyphosa, pomona, and bratislava have increased.

10. Signalment
Young-adult, large-breed, outdoor dogs; however, small dogs in urban areas can also contract the disease.

11. Transmission
It is transmitted by many animals such as rats, skunks, opossums, raccoons, foxes, etc. It is spread through contact with contaminated soil or water from waste products of an infected animal. The disease can be contracted by:
ingesting contaminated food or water
through broken skin, and mucous membrane (eyes, nose, sinuses, mouth)
coming in contact with contaminated soil or water

12. Transmission
Leptospirosis is transmitted between animals through contact with infected urine which can get into water and soil and can survive there for weeks to months, venereal and placental transfer, bite wounds, digestion of infected tissue. Crowding in a kennel can also increase the spread of the infection.

13. Transmission
Indirect transmission occurs through exposure of susceptible animals to contaminated water sources, food, or even bedding. A suitable habitat for Leptospira is slow or stagnant water, resulting in outbreak during periods of flooding.

14. Transmission
In dry areas, infections are more common around water sources. Freezing greatly reduces the chance of the organism surviving in the environment, which is why infections are most common in summer and fall and why infections are more prevalent in temperate areas.

15. Transmission
It is not spread from person to person, except in vary rare cases when it is transmitted through breast milk or from a mother to her unborn child. The bacteria can enter through skin or mucous membranes, especially through a cut or scratch.

16. Risk Factors when considering Leptospirosis
Occupational exposure- farmers, ranchers, slaughterhouse workers, trappers,
Veterinarians, loggers, sewer workers, rice field workers, and military personnel.
Recreational activities- fresh water swimming, canoeing, kayaking, and trail biking in warm areas.
Household Exposure- petting dogs, domesticated livestock, infected rodents.

17. Clinical Signs Primary: -Shivering - Muscle Tenderness - Vomiting
the incubation period varies between 3 and 20 days, some dogs & cats may not show clinical signs.
Primary:
-Shivering
- Muscle Tenderness
- Vomiting
- Diarrhea
- Polyuria
- Polydipsia
- Anorexia
Secondary:
- Dehydration
- Jaundice
- Coagulopathy ( inability to stop bleeding)
- Dyspnea

19. Human Symptoms
Symptoms can take days (average 10 days) to develop, and may include:
Dry cough
Fever
Headache
Muscle pain
Nausea, vomiting, and diarrhea
Shaking chills
Less common symptoms include:
Abdominal pain
Abnormal lung sounds
Bone pain
Conjunctivitis
Enlarged lymph glands
Enlarged spleen or liver
Joint aches
Muscle rigidity
Muscle tenderness
Skin rash
Sore throat

20. Diagnostics Complete blood cell count Serum chemistry Serology
Leukocytosis
Thrombocytopenia
Serum chemistry
Increased blood urea nitrogen (BUN)
Creatinine
Increased ALT
Bilirubinuria
Serology
Serology is the most useful and frequently used diagnostic test for dogs.

21. Diagnostics?
- MAT (microagglutination test) will present with clinical signs of disease prior to the development of antibodies measurable by MAT
- ELISA (enzyme linked immunosorbent assay)
- PCR (polymerase chain reaction) will be positive on blood very early in infection usually prior to seroconversion. Urine will become positive 7–14 days after infection at which time leptospires may or may not be detected in the blood.
- Serologic testing is the most commonly used method for diagnosis of leptospirosis. Negative serologic test results may occur in the early phase of infection. Dogs suspected of being infected but who test negative should be re-tested in two-to-three weeks.

22. Case
In July 1998, athletes from 44 states and seven countries participated in triathlons in Springfield,Ill.The Illinois Department of Health, the U.S. Department of Agriculture, and the Centers for Disease Control investigated an outbreak of acute febrile illness in which 110 of 1194 (9.2%) participants experienced chills, headache, myalgia, diarrhea, eye pain or conjunctivitis. The investigation indicated that Leptospira bacteria caused illness in some of the athletes exposed to Lake Springfield, where the Illinois triathlon was held.

23. Case
In 1988, a 45-year-old San Antonio man experienced a throbbing frontal headache, diarrhea and fever for four days. He was employed as a meat-packing plant worker, and it was first thought that he might have contracted an infection at work. However, during an epidemiological investigation it was found that his two dogs at home had high MAT titers for three Leptospira serovars. The patient also had high titers to the same serovars, and it was concluded that his exposure was from the dogs at home. Leptospires had been cultured from the patient’s urine specimens to further confirm the diagnosis.

24. Case
In December 2002, a Beagle and a crossbred dog in Dallas tested by TVMDL had high MAT titers for leptospirosis. The wife of the owner of the dogs was later diagnosed by her physician as having leptospirosis. Close contact with infected pets is enough to transmit leptospires from pets to humans.

25. Pathologic Lesions of Disease
Gross findings can include petechial or ecchymotic hemorrhages on any organ, pleural, or peritoneal surface; hepatomegaly; and renomegaly.
The liver is often friable with an accentuated lobular pattern and may have a yellowish brown discoloration.
The kidneys may have white foci on the subcapsular surface.
Microscopic findings in the liver may include hepatocytic necrosis, nonsuppurative hepatitis, and intrahepatic bile statis, while swollen tubular epithelial cells, tubular necrosis, and a mixed inflammatory reaction may be seen in the kidneys.
Chronic hepatitis and chronic interstitial nephritis are described in less severe cases.

26. Pathological lesions of Leptospirosis
In animals, there really isn’t any type of lesions that can be caused from the disease. Jaundice and Icterus are other types of symptoms you would see through the skin.
Although in humans, this bacterial disease is characterized by a skin rash and flulike symptoms caused by a spirochete bacterium excreted by infected rodents

27. Purulolymphoplasmacytic tubulointerstital nephritis in a dog that died of leptospirosis. (Hematoxylin and eosin stain, courtesy of Noah's Arkive, The University of Georgia).

28. Spirochetes of Leptospira sp
Spirochetes of Leptospira sp. appear as black threads within the lumina or renal tubules (van Orden stain, courtesy of Noah's Arkive, The University of Georgia).

29. Spirochetes of Leptospira sp
Spirochetes of Leptospira sp. stain red-brown along the lumenal walls of renal tubules (immunoperoxidase stain, courtesy of Noah's Arkive, The University of Georgia).

30. Recommended Treatment
Leptospirosis is treated primarily with antimicrobial therapy. In uncomplicated infections that do not require hospitalization, oral doxycycline has been shown to decrease duration of fever and most symptoms.
Hospitalized patients should be treated with intravenous fluids. A recent clinical trial showed that third-generation cephalosporins are as effective as doxycycline and penicillin in the treatment of acute disease.

31. Prognosis
Prognosis depends upon how early treatment begins. Even after treatment with antibiotics, liver or kidney disease may still develop. Up to 25% of infected dogs will not survive the initial infection. 33% to 40% of infected dogs will develop chronic renal failure.

32. Prevention
Vaccinate your pet yearly, vaccinated dogs may still be susceptible to infections with other serovars.
Keep animals out of contact with potential sources of infection for example, contaminated water sources and wildlife reservoirs.
Control the rodent population.
If a dog has been recently exposed to leptospirosis it may be treated with oral amoxicillin or doxycycline for 7-10 days to prevent infection.

33. Client Education
Animals with leptospirosis are contagious to humans and other animals.
Supportive care is important.
Treatment and diagnosis are expensive.
Vaccinations do not protect your dog from other serovars with which it may come in contact.

34. Are vaccinations one sure way to guarantee your pet won’t get Lepto?
Leptospira is a gram negative spirochete bacteria that is very common in this region of the United States. There are over 250 different serovars (subtypes) and it is a zoonotic disease. Unfortunately, vaccination against one strain does not protect against the other strains.

35. Resources www.peteducation.com www.nlm.nih.gov www.cdc.gov

36. References http://www.cdc.gov/ncidod/eid/vol11no07/04-1172.htm
Common Disease of Companion Animals-Textbook