Leptospirosis in dogs - current aspects regarding clinical signs, diagnosis, therapy and prevention

Leptospirosis in dogs current aspects regarding clinical signs, diagnosis, therapy and prevention Canine leptospirosis is a re-emerging zoonotic infectious disease which is primarily caused by leptospiral spirochetes of the genomospecies Leptospira interrogans and Leptospira kirschneri. Indirect transmission of leptospires mainly occurs through the exposure of susceptible animals to a contaminated environment (urine of reservoir hosts). The leptospires enter the organism via intact mucous membranes or skin lesions. The course of the disease is dependent on the host's immunity, the infecting dose and the virulence of the organism. In dogs with low or absent antibody titres, leptospires can spread and replicate in many tissues. Acute renal failure is the most common clinical feature, but other organs such as liver, lung (haemorrhage), eyes and muscles are also involved. Common laboratory abnormalities include renal azotaemia, altered liver parameters, thrombocytopenia, leucocytosis, anaemia, proteinuria, glucosuria, and bilirubinuria. The diagnosis is based on a combination of clinical signs/laboratory abnormalities and indirect (microscopic agglutination test, ELISA) and direct (PCR, culture) tests. Dogs with acute leptospirosis require intensive care management. In addition to a biphasic anti-infective therapy (amoxicillin and doxycycline), affected dogs require individually adjusted fluid therapy, antiemetics, gastric protectants and analgesics according to their clinical signs. An intensive monitoring is needed mainly because of the risk of anuric renal failure and pulmonary haemorrhage. Haemodialysis may be life-saving. The prognosis is dependent on the severity of the clinical signs and associated complications; the mortality rate is higher in dogs with pulmonary involvement. Since leptospirosis is a zoonotic disease strict hygiene measures have to be taken. In Germany bivalent vaccines and recently tri- and tetravalent vaccines are available.