Metastrongyloidea - dog/cat Flashcards
What are some genus and species of relavent Metastrongyloidea?
- Angiostrongylus vasorum
- Aelurostongylus abstrusus
- Oslerus osleri
What are some general characteristics of Metastrongyles?
- Indirect LC (O. osleri has a direct LC)
- IMH - molluscs
- clinically mild/asymptomatic
- Lung and heart dz
What animal(s) does Angiostrongylus vasorum affect?
Direct or indirect LC?
IMH if indirect?
Where is the site of infection?
- Dog, fox
- Indirect - molluscs
- Right ventricle, pulmonary artery
- It’s also called the ‘French Heartworm’
Describe the life cycle of Angiostrongylus vasorum.
- Indirect - mollusc (snail)
- PPP - 7 weeks
- adults in heart release EGGS
- eggs hatch in pulmonary capillaries and L1’s break into alveoli and migrate up lungs
- L1 are swallowed and present in feces
- L1 taken in by mollusc (snail) where they develop to L3
- The snails are eaten by the dogs, foxes and the L3’s find their way to local lymph nodes where they develop to adults
- Adults then migrate to R side of the heart.
What is the pathogenesis of Angiostrongylus vasorum?
- Chronic infection
- Associated with adults in large vessels and eggs in pulmonary capillaries
- Chronic congestive heart failure
- Fibrosis in arteries - “pipe stem” feel
- Lung mottled by penetrating L1’s
- Subcutaneous hematoma - interference with normal blood clotting.
What are some clinical signs of an Angiostrongylus vasorum infection?
- Early on - asymptomatic
- Later - increased RR, cough during exercise
- Heavy worm burden - symptoms in resting dog
- fainting
- subcutaneous hematoma (clotting disturbances due to parasite excretory/secretory products)
- Scleral hemorrhage
- Brain/spinal cord hemorrhages possible
How do you diagnose Angiostrongylus vasorum infection?
How do you treat?
- Fecal sample - L1 has characteristic tail with small spine
- Antigen test
- PCR
- Treat with fenbendazole
What is/are the host(s) of Aelurostrongylus abstrusus?
Direct or Indirect?
If indirect, IMH?
Site of infection?
- cat
- Indirect - molluscs (snail)
- lungs - parenchyma and small bronchioles
What is the pathogenesis of Aelurostrongylus abstrusus?
- not a whole hell of a lot
- small granulomas in lung
- rarely larger lesions
- muscular hypertrophy/hyperplasia of broncholes, alveolar ducts, and pulmonary arteries
- Resolution of all but hypertrophy/hyperplasia after treatment
What are some clinical signs of Aelurostrongylus abstrusus?
Is the diagnosis on fecal egg observation or L1?
- mild
- chronic moist cough
- Dx is on L1
Where is Oslerus osleri found in the dog?
Is this a metastrongyloidea or filarioidea?
Indirect or direct life cycle?
If indirect, IMH?
- Found in nodules at the tracheal bifurcation
- Metastrongyloidea
- Direct - dogs become infected by ingestion of L1
How is diagnosis made on Oslerus osleri?
- Clinical signs (chronic dry cough, exercise intolerance)
- L1 in sputum or feces
- L1 has distinctive S shaped tail
