Dirofilariasis is a rare disease in humans. We report here a case of a 48-year-old male who was diagnosed with pulmonary dirofilariasis in Korea. On chest radiographs, a coin lesion of 1 cm in diameter was shown. Although it looked like a benign inflammatory nodule, malignancy could not be excluded. So, the nodule was resected by video-assisted thoracic surgery. Pathologically, chronic granulomatous inflammation composed of coagulation necrosis with rim of fibrous tissues and granulations was seen. In the center of the necrotic nodules, a degenerating parasitic organism was found. The parasite had prominent internal cuticular ridges and thick cuticle, a well-developed muscle layer, an intestinal tube, and uterine tubules. The parasite was diagnosed as an immature female worm of Dirofilaria immitis. This is the second reported case of human pulmonary dirofilariasis in Korea.
Animals ; Diagnosis, Differential ; Dirofilaria immitis/*isolation & purification ; Dirofilariasis/*diagnosis/parasitology/surgery ; Humans ; Lung/pathology ; Lung Diseases, Parasitic/*diagnosis/parasitology/surgery ; Male ; Middle Aged ; Republic of Korea ; Treatment Outcome

From 2006 to 2010, hospitals in Hanoi treated 10 human patients for dirofilariasis. The worms were collected from parasitic places, and identification of the species was completed by morphology and molecular methods. Ten parasites were recovered either from the conjunctiva (n=9) or subcutaneous tissue (n=1). The parasites were 4.0-12.5 cm in length and 0.5-0.6 mm in width. Morphological observations suggested all parasites as Dirofilaria repens. Three of the 10 parasites (1 from subcutaneous tissue and 2 from eyes) were used for molecular confirmation of the species identification. A portion of the mitochondrial cox1 (461 bp) was amplified and sequenced. Nucleotide and amino acid homologies were 95% and 99-100%, respectively, when compared with D. repens (Italian origin, GenBank AJ271614; DQ358814). This is the first report of eye dirofilariasis and the second report of subcutaneous tissue dirofilariasis due to D. repens in Vietnam.
Adult ; Aged ; Animals ; Cyclooxygenase 1/genetics ; Dirofilaria repens/anatomy & histology/genetics/*isolation & purification ; Dirofilariasis/*diagnosis/parasitology/*pathology ; Eye/*parasitology ; Eye Diseases/parasitology ; Female ; Humans ; Male ; Middle Aged ; Molecular Diagnostic Techniques/methods ; Parasitology/methods ; Phylogeny ; Polymerase Chain Reaction ; Sequence Analysis, DNA ; Sequence Homology ; Skin Diseases/parasitology ; Subcutaneous Tissue/*parasitology ; Vietnam