There is no evidence that Dirofilaria can complete a life cycle and produce microfilaremia in humans. Our patient raises an interesting question. How frequently might dog owners develop otherwise unexplained eosinophilia, Löffler syndrome, and symptoms of meningeal irritation with pleocytosis due to dirofilarial infestations?
Dirofilarial infestation as a cause of "coin lesion" on chest x-ray film has been emphasized, but other more subtle symptoms, signs, and serologic evidence alone make a definite diagnosis of human dirofilariasis difficult.
(JAMA 228:1018-1019, 1974)