Leptospirosis

Leptospirosis is an infection of bacterial spirochetes, which dogs acquire when subspecies of the Leptospira interrogans penetrate the skin and spread through the body by way of the bloodstream. These bacteria can be found worldwide in soil and water.

Etiology Aerobic gram-negative spirochetes that are fastidious slow growing have characteristic corkscrew-like motility The taxonomy of Leptospira is complex and can be confusing. Leptospira were divided into two groups; The pathogenic Leptospira were all classified as members of L interrogans The Saprophytic Leptospira were classified as L biflexa

Epidemiology Leptospirosis is found throughout the world. The infection (and disease) is more prevalent in warm, moist climates and is endemic in much of the tropics. In temperate climates, the disease is more seasonal, with the highest incidence after periods of rainfall. Rainfall; Contaminated environment Poor Sanitation; Inadequate drainage facilities Presence of rodents, cattle & stray dogs

Pathogenesis Leptospires invade the body after penetrating exposed mucous membranes or damaged skin Leptospires circulate in the blood and replicate in many tissues including the liver, kidneys, lungs, genital tract, and CNS for 7–10 days. During the period of bacteremia and tissue colonization, the clinical signs of acute leptospirosis, which vary by serovar and host, occur Agglutinating antibodies can be detected in serum soon after leptospiremia occurs and coincide with clearance of the leptospires from blood and most organs. As the organisms are cleared, the clinical signs of acute leptospirosis begin to resolve, although damaged organs may take some time to return to normal function.

Clinical Signs Sudden fever and illness Sore muscles, reluctance to move Stiffness in muscles, legs, stiff gait Shivering Weakness Depression Lack of appetite Increased thirst and urination, may be indicative of chronic renal (kidney) failure, progressing to inability to urinate Rapid dehydration

Vomiting, possibly with blood Diarrhea - with or without blood in stool Bloody vaginal discharge Dark red speckled gums (petechiae) Yellow skin and/or whites of eyes – anemic symptoms Spontaneous cough Difficulty breathing, fast breathing, irregular pulse Runny nose Swelling of the mucous membrane Mild swelling of the lymph nodes

Necropsy Findings Gross necropsy findings can include: Jaundice Effusions Petechial or ecchymotic hemorrhages on any organ Pleural, or peritoneal surface The kidneys and liver may be enlarged, and lungs may be wet, heavy, and discolored 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.

Diagnosis Chemical blood profile Complete blood count Urinalysis Electrolyte panel Fluorescent antibody urine test Urine and blood cultures Agglutination test

Differential Diagnosis Fever Viral fever, Malaria, Typhus Jaundice Malaria, Viral hepatitis, Sepsis Renal Failure Malaria, Hanta virus, Sepsis Meningitis Bacterial / Viral causes Hemorrhagic Fever Dengue, Hanta virus, Typhus

Treatment Fluid therapy- primary treatment Antiemetic Blood transfusion Antibiotics- penicillin, tetracycline and fluoroquinolones

Prevention and Control Vaccination Avoid contact with your dog’s urine; If you are cleaning surfaces that may be contaminated or have urine from an infected pet on them, use an antibacterial cleaning solution or a solution of 1 part household bleach in 10 parts water. Encourage your dog to urinate away from standing water or areas where people or other animals will have access; Preventing dogs from swimming in ponds and slow-moving water can also help.

Make sure to inspect kennels before placing your dog in one – the kennel should be kept very clean and should be free of rodents (look for rodent droppings). Activity should be restricted to cage rest while your dog recovers from the physical trauma of this infection. Limiting pet’s access to contaminated water