Clinical signs
• Pyrexia
• Vomiting, diarrhoea, altered appetite, abdominal pain
• Shivering; muscle pain or weakness
• Dehydration, oliguria, anuria (sometimes polyuria or polydipsia)
• Shock, tachycardia, arrhythmias
• Lethargy
• Bleeding disorders
• Coughing, dyspnoea or tachypnoea (rhinitis, tonsillitis in some cases)
• Icterus, hepatic encephalopathy
• Conjunctivitis, scleral injection, erythematous, bullous lesions, uveitis (which can be delayed for many weeks to months)
Diagnosis
The microscopic agglutination test (MAT) detects the presence of antibodies against Leptospira in a dog's blood. If the level of antibodies (called a titer) is high enough or can be shown to rise over time, then infection is confirmed. Other serology tests, such as ELISA or rapid test, are also applied to the detection of antibodies against Leptospira in a dog's blood.
Many molecular assays, including real-time PCR, have been developed that detect pathogenic Leptospira DNA in clinical specimens. Detection of leptospiral nucleic acid in blood or tissues is diagnostic for infection, while detection in kidney tissue or urine is consistent with either infection or colonization.