Histopathology of the lungs of rabbits experimentally infected with Dirofilaria immitis.

The lungs of rabbits experimentally infected with Dirofilaria immitis were examined histopathologically, to compare the changes with those seen in human pulmonary dirofilariasis. Eight rabbits were infected subcutaneously with two to eight immature worms to induce pulmonary dirofilariasis. Obstructive changes, similar to those reported in human pulmonary dirofilariasis, were observed in the blood vessels surrounding the worms. A form of arteritis, similar to occlusive arteritis, and periarteritis were also observed in the lungs of the rabbits. These results suggest that experimentally induced dirofilariasis in the rabbit is a useful animal model for human pulmonary dirofilariasis.