Unit 4 - Equine Hepatic/Blood Borne Flashcards
What are the common infectious causes of anemia?
Equine granulocytic anaplasmosis
Equine infectious anemia
What is the FAD cause of anemia?
Piroplasmosis
What are the non-infectious causes of anemia?
Neonatal isoerythrolysis Autoimmune hemolytic anemia Drug induced - Penicillin, TMS Toxin induced - red maple leaf Liver failure
What is the etiologic agent of equine anaplasmosis?
Anaplasma phagocytophilum
How is equine anaplasmosis transmitted?
Bloodborne, primarily ticks
What does A. phagocytophilum infect?
Neutrophils and eosinophils resulting in the development of morulae
What clinical signs are associated with A. phagocytophilum infection?
Fever of unknown origin, anorexia initially
Depression, reluctance to move
Petechiae, icterus, and edema
What age group of horses typically gets equine anaplasmosis more often?
Older horses
What will you see on CBC in a horse with anaplasmosis?
Pancytopenia - leukopenia due to neutropenia and lymphopenia, thrombocytopenia, and anemia
How is equine anaplasmosis diagnosed?
Blood smear
PCR
IFA - 4 fold increase in titers
What will you see on blood smear in a patient with anaplasmosis?
Morulae present in the neutrophils or eosinophils
How is equine anaplasmosis treated?
Disease is generally self-limiting if no complications develop
Supportive care
Oxytetracycline
How is equine anaplasmosis prevented and controlled?
Tick control
What is the etiologic agent of equine infectious anemia?
Equine infectious anemia virus
How is EIA transmitted?
Bloodborne, primarily blood-sucking insects but can be iatrogenic
What are the forms of EIA?
Acute, common, inapparent
What is the most common form of EIA?
Inapparent
What clinical signs are associated with acute EIA?
Fever, depression, weight loss, and edema
Thrombocytopenia
Hemolytic anemia
Initial attack lasts 3-5 days
What clinical signs are associated with chronic EIA?
Short episodes of acute disease
Development of hyperglobulinemia
May develop emaciation
What clinical signs are associated with inapparent EIA?
Recurrent or persistent episodes of viremia without obvious clinical disease
How is EIA diagnosed?
Serology (definitive)
What serologic tests can be used to diagnose EIA?
Coggins test (AGID) Competitive ELISA
What is the requirement for EIA diagnosis?
Must be done by USDA accredited veterinarians and sent to USDA accredited labs
How is EIA treated?
There is no treatment - euthanize, slaughter, or lifetime quarantine
How is EIA prevented and controlled?
Quarantine the premises
Never reuse needles, syringes
Use blood products from test negative animals
Clean and disinfect dental and surgical equipement
General fly control and sanitation
T/F: EIA is not reportable
False- it is
What is the etiologic agent of equine piroplasmosis?
Babesia caballi or Theileria equi
T/F: Equine piroplasmosis is considered a FAD even though it was ‘eradicated’ in the US
True - it is still frequently identified
How is equine piroplasmosis transmitted?
Bloodborne - primarily ticks
What cells does equine piroplasmosis infect?
RBCs
What are the forms of equine piroplasmosis disease?
Acute, subclinical, chronic
What clinical signs are associated with acute equine piroplasmosis?
Fever, lethargy, inappetence, anemia, icterus, hemoglobinuria, incoordination, swelling of the eyelids, and death
How are chronic equine piroplasmosis patients developed?
The survivors remain chronic carriers
Which form of equine piroplasmosis is the most commonly identified in the US?
Chronics
How is equine piroplasmosis diagnosed?
Presence of organism on blood smears
PCR
cELISA (positive with chronic)
CF
What are the options for treatment of equine piroplasmosis?
Permanent quarantine
Euthanasia
Export from the country
Long-term quarantine and enrollment in USDA-approved high-dose imidocarb treatment program
T/F: Equine piroplasmosis is reportable
True
What are the requirements for all horses entering the US in regards to equine piroplasmosis?
They must test negative via both cELISA and CF prior to entry
What prevention and control methods are recommended for equine piroplasmosis?
Never reuse syringes
Only use blood products from negative test animals
Clean and disinfect dental and surgical equipment
Tick control
What are the bacterial infectious causes of hepatitis?
Ascending cholangiohepatitis Clostridium piliforme (foals
What are the viral infectious causes of hepatitis?
Theiler’s disease
Equine parvovirus-hepatitis
What are the non-infectious causes of hepatitis?
Toxin induced
Metabolic
Idiopathic
Neoplasia
What is the etiologic agent of Tyzzer’s disease?
Clostridium piliforme
What is the suspect mode of transmission of Tyzzer’s disease?
Suspect fecal-oral
What clinical signs are associated with Tyzzer’s disease?
Acute hepatitis of foals <2 months of age - depression, fever, icterus, and diarrhea progressing to seizures, coma, and death
How is Tyzzer’s diagnosed?
Post-mortem - acute multifocal hepatitis
How is Tyzzer’s treated?
It is challenging - antibiotic and aggressive supportive care
What is theiler’s disease also known as?
Serum hepatitis
T/F: Theiler’s disease is the most common cause of acute hepatitis and liver failure
True
How is Theiler’s disease transmitted?
It is associated with administration of equine biologic products and also associated with contact with serum hepatitis cases
T/F: There are 4 causes of Theiler’s disease
true
What are the four viruses recently reported to be associated with Theiler’s disease?
Equine parvovirus-hepatitis
Non-primate hepacivirus
Theiler’s disease associated virus
Equine pegivirus
What clinical signs are associated with Theiler’s disease?
Acute onset of hepatic failure
Depression, inappetence, icterus, photoactive dermatitis, hepatic encephalopathy
Acute death is possible
What chemistry abnormalities are associated with Theiler’s disease?
Increased bilirubin, bile acids, and liver enzymes
How is Theiler’s disease diagnosed?
Liver biopsy
PCR panel
Necropsy
What will the liver look like at necropsy in a Theiler’s disease patient?
Dish-rag liver
How is Theiler’s disease treated?
Supportive care only
How is Theiler’s disease prevented and controlled?
Screening of commercial blood products/donors
Close monitoring of contact cases
What is the etiologic agent of Lyme Disease?
Borrelia burgdorfori
Where is lyme disease widespread?
In the northern hemisphere
What transmits lyme disease?
Larval and nymph stages of Ixodes ticks
What clinical signs are associated with lyme disease?
Non-specific signs
Most commonly reported signs are lameness in multiple limbs, hyperesthesia
When do clinical signs of lyme disease occur?
During the chronic disease stage - 2-5 months or longer after infection
What rare clinical syndromes have the most evidence to be caused by lyme disease?
Neuroborrellosis, uveitis, cutaneous pseudolymphoma
How is lyme disease diagnosed?
Serology: IFAT, ELISA, Western blot, C6 SNAP test, multiplex ELISA
What is the confirmatory diagnostic test for lyme disease?
Western blot
T/F: A positive test without vaccination proves causation while a negative result is highly suggestive that it is not the cause of disease.
False- all of the statement is correct except that a positive test without vaccination means there has been exposure but that it was not the cause of the disease
How is lyme disease treated?
Ideal treatment is unknown - tetracyclines, B-lactams
Neuroborreliosis has a poor response
How is lyme disease prevented and controlled?
Tick control
Extra-label vaccination
