Showing posts with label Leptospirosis. Show all posts
Showing posts with label Leptospirosis. Show all posts

Solution for case 8


Tentative diagnosis: Hepatitis. An increase in AP, ALT and total bilirubin is indicative of liver problems. The mild elevation in total bilirubin explains the slightly yellow mucus membranes. The generalized lymphadenopathy and increased globulins could be indicative of a systemic infection that in this case is affecting primarily the liver, causing hepatitis.

Further diagnostic tests:
  • Paired serum samples
  • Serology
  • Immunofluorescence
  • Ultrasound
  • Liver biopsy
Differentials:
  • Infectious hepatitis: bacterial, fungal or other
  • Leptospirosis
  • Granulomatous hepatitis
  • Toxic hepatopathy
  • Fulminant infectious disease: parvovirus, canine distemper
  • Portosystemic shunting
Hepatitis can have many different causes. The main disease suspected to be causing the hepatitis is leptospirosis. Leptospira interrogans serovar Bratislava is very prevalent in the area and is not covered by the leptospirosis vaccine. The vaccine only includes serovars Canicola, Icterohemorrhagiae, Grippotyphosa, and Pomona. No cross protection exists between serovars. The typical clinical signs of leptospirosis are fever, depression, lethargy, anorexia, myalgia, vomiting, lumbar pain from renomegaly and nephritis, icterus, bilirubinuria, cholestasis and/or hepatic necrosis, renal failure. It has been reported that many young dogs suffer more from liver problems and not the kidney when infected with leptospirosis.
Extrahepatic bacterial or fungal infections could also cause hepatitis, but this case was not showing clinical signs of having an infection in other body systems that could have traveled to the liver. However, since the owner was not with the dog during the entire summer the patient could have developed a primary infection, that later traveled to the liver, but at the present time is not evident.

Many hepatotoxins such as high amounts of acetaminophen, aflatoxins, blue-green algae, heavy metals; certain herbicides, fungicides, insecticides and rodenticides could cause liver problems. No ingestion or access to any of these was reported by the owner.

Other causes of hepatitis are Canine Adenovirus-1, but this patient vaccinated. Toxoplasmosis is a rare disease because the body is usually able to eliminate the infection. However some young dogs are not able to control the infection and Toxoplasma tachyzoites invade tissues throughout the body and replicate intracellularly until cells burst, causing necrosis. If the Toxoplasma tachyzoites invade the liver clinical signs associated with hepatitis could be seen.

Canine cholangiohepatitis is rare and associated with ascending biliary tract infections (Salmonella sp., Campylobacter jejuni), choleliths, coccidiosis, and surgery of the biliary tract. Clinical signs include anorexia, vomiting, diarrhea, lethargy, PU/PD, fever, abdominal pain, hyperbilirubinemia and elevated AP and GGT. To make a definitive diagnosis samples should be submitted for aerobic and anaerobic cultures and sensitivity.

Idiopathic hepatic fibrosis is a rare disease in young dogs, usually less than 2 years of age, is not associated with any underlying inflammatory conditions. Clinical signs include ascites, hepatic encephalopathy, weight loss, vomiting, diarrhea, portal hypertension, portosystemic shunt, microcytic anemia, elevated AP and ALT and hypoalbuminemia. Microhepatica can be noted on radiographs.

Hepatic amyloidosis is a rare familial disease. Clinical signs include anorexia, PU/PD, vomiting, icterus and hepatomegaly. Diagnosis is made by identifying amyloid deposits in a liver biopsy. Glycogen storage disease is caused by a rare deficiency in glucose-6-phosphatase or in amylo-1,6-glucosidase, this results in a failure of glycogen to be released from the cell. Therefore, glycogen accumulates within the liver and other organs. Enzyme analysis of fresh frozen samples of liver, muscle or skin is needed for diagnosis. Prognosis is poor and most dogs succumb to these diseases at a young age.

Treatment of possible leptospirosis: Administration of 0.9% NaCl fluids IV to prevent dehydration was started along with antibiotic treatment with Ampicillin 500mg orally TID (three times a day). The patient is to be fed three times a day l/d diet in order to prevent any further liver damage and to try to increase body weight. A CBC test is to be repeated in three days to determine if the treatment plan is being effective and assess the health status of the patient.

Need to assess the health and degree of clinical signs in patient's kins. There may be need to look into familial disease.

Solution for case 6

Tentative diagnosis: Leptospirosis; Clinical signs with history of exposure to contaminated urine suggest leptospirosis.
Differential diagnosis:
  • Immune-mediated hemolytic anemia
  • Infectious canine hepatitis virus
  • Canine herpesvirus
  • Hepatic neoplasia
  • Trauma/bacteremia
  • Rocky Mountain spotted fever
  • Ehrlichiosis
  • Toxoplasmosis
  • 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
  • Serology
  • Microscopic agglutination test
  • Not good if the dog was previously vaccinated, or infected or had passive immunity
  • ELISA (anti-lepto-antibodies), DNA probes, PCR
Treatment:
  • Supportive therapy (IV fluids) and antibiotics
  • Ampicillin: Leptospiremia
  • 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
Prevention:
  • Vaccination at yearly intervals and more often in enzootic areas
  • Be aware of new vaccines for Leptospirosis that induce immunity for new serovars
Be concern that it is a Zoonotic disease!!
  • Owner of the pet should be oriented about how to manage the dog and give the complete dose of antibiotics to eliminate the carrier stage
  • Clean the cage with bleach or diluted iodine
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.