Epidemiology

• Rare etiology of solitary pulmonary nodule

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Etiology

• Dirofilaria immitis (dog heartworm)
  • Mosquito-acquired

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Physiology

• Humans are an imperfect host for this parasite: hence, dead immature larvae may embolize into pulmonary circulation, producing infarction and inflammation

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Diagnosis

• CXR/Chest CT Pattern
  • Well-defined nodule (involvement of larger pulmonary arteries may produce a wedge-shaped density simulating pulmonary infarction)
    • Location: no known predilection
    • Calcification: sometimes
    • Cavitation: sometimes
  • Infiltrative lesions (uncommon):

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Clinical Manifestations

Pulmonary Manifestations

• Lung Nodule (see Lung Nodule or Mass, Lung Nodule or Mass)

Other Manifestations

• xxx

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Treatment

• No treatment is necessary in humans

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References

• xx