Type of parasite: nematode
Species: Dirofilaria immitis, Dirofilaria repens, Dirofilaria tenuis, others
Transmission: Microfilaria are passed by mosquito, from an infected dog to the human. The larvae develop in subcutaneous tissue forming a nodule. They may remain there or migrate into the venous bloodstream.
Clinical features:
(1) Subcutaneous nodules, including around the orbit.
(2) The person lives or has lived in a tropical, subtropical or warm temperate region endemic for a Dirofilaria species.
Laboratory findings:
(1) A biopsy of the subcutaneous lesion shows inflammation centered about larvae which can be found if multiple section are examined.
(2) A mild eosinophilia may be present.
(3) Microfilaria are absent from the peripheral blood.
