Tentative diagnosis: Leptospirosis; Clinical signs with history of exposure to contaminated urine suggest leptospirosis.
- Immune-mediated hemolytic anemia
- Infectious canine hepatitis virus
- Canine herpesvirus
- Hepatic neoplasia
- Rocky Mountain spotted fever
- Renal neoplasia/renal calculi
Leptospirosis is an infectious disease that can cause renal azotemia as the bacteria cause damage to the renal tubules decreasing the capacity of the kidneys to excrete urea. Also Creatinine levels could be high if the glomerular filtration rate of the kidney decreases in a renal failure. Usually dogs with subacute Leptospirosis will present azotemia, high liver enzymes (AP more high than ALT), icterus, dehydrated, mild anemic (Leptospirosis damaging RBC walls and endothelium) and 20% of dog with thrombocytopenia do to vasculitis. High liver enzymes are also observed in dogs with leptospirosis. All these signs make this patient a suspect of subacute leptospirosis. Also clinical signs and history of “rats around the environment” increase the suspicion of leptospirosis.
Urinary tract obstruction, a post renal condition (frequently in male dogs) can also increase BUN/Creatinine levels but usually clinical signs as hematuria and urinary incontinence will be seen in the dog. This was not in this case, as he was urinating with no signs of hematuria and no urinary incontinence.
Further diagnostic tests:
- Leptospira isolated from blood and urine after 7-10 days of infection
- 2 weeks after infection use liquid culture to growth
- Dark field microscopic, FA, Silver impregnation technique for tissue (Kidney, liver, lung) with the organism
- Microscopic agglutination test
- Not good if the dog was previously vaccinated, or infected or had passive immunity
- ELISA (anti-lepto-antibodies), DNA probes, PCR
Supportive therapy (IV fluids) and antibiotics
Dosage 5-10 mg/Kg IV, IM, SQ BID
Ampicillin 300 mg à 0.3 ml SQ BID
Doxycycline: eliminate renal carrier state
Dosage 5-10 mg/kg PO, SID
Doxycycline (100mg)tablets BID
Should be given for 1 month
Be concern that it is a Zoonotic disease!!
If the dog does not recover after the treatment further diagnostic test should be performed as kidney and/or liver biopsy, ultrasound, and x-rays.