RESUMEN
Man is host to three distinct trichomonad species such as Trichomonas vaginalis, T. hominis, and T. tenax. Although reports of trichomonads found outside their natural habitat are rare, sporadic case reports have appeared describing trichomonads in the respiratory tract. The route of infection is unknown, but possible mechanisms include invasion from mouth, oral sex, bronchopleural or pleuroenteral fistula. Pulmonary trichomoniasis is a kind of oppotunistic infection and is usually caused by aspirated T. tenax in male adult patientis with chronic purulent or necrotic pulmonary disease. A 63-year-old male patient with alcoholic liver cirrhosis and chronic bronchiectasis was admitted due to copious sputum, dyspnea, fever and severe weight loss. On the thoracentesis from his right pleural cavity, 1 L of foul-smelling, brownish-yellow exudate was withdrawn and showed a large number of neutrophil, bacteria and numerous flagellated, actively motile organisms with typical appearance of thrichomonads in wet preparation. This patient was expired due to sepsis and insufficiency of multiple organs inspite of chemotherapy with metronidazole, cefuroxime and gentamicin on day 35 of admission. So, we report the first case of pulmonary trichomoniasis diagnosed in wet preparation of pleural fluid in Korea.