Two unusual occurrences of pleural trichomonosis due to a new Tetratrichomonas species previously reported but not named were confirmed. In one patient, Trichomonas tenax and a Tetratrichomonas species were also detected in the oral cavity by molecular methods. We suggest that this new Tetratrichomonas species be named Tetratrichomonas empyemagena.
CASE REPORTSC ase 1 is that of a 54-year-old male from Mexico City with uncontrolled type 2 diabetes who was admitted to the hospital with a history of 1 week of malaise, poor food intake, chills, and fever after developing right thoracic pain, dyspnea, and fatigue; he denied any history of choking or trauma in recent days. Dullness on percussion and decreased breathing sounds were noted over his right chest. His blood pressure was 120/50 mmHg, his heart rate was 120 beats/min, his respiratory rate was 30 breaths/min, his white blood cell count was 45,000/mm 3 , his platelet count was 565,000/mm 3 , his glucose level was 503 mg/dl, his albumin level was 1.6 g/dl, and his arterial HCO 3 level was 5.6 meq/liter. An initial chest X-ray and computed tomography (CT) scan showed a right pleural effusion that was drained (700 ml), and the pleural fluid was sent for microbiological analysis. Its macroscopic appearance was that of a brownish purulent fluid. Microscopic examination revealed Gram-positive cocci and Gram-negative bacilli, as well as numerous motile and flagellated protozoa that were initially identified as trichomonads because of their morphological characteristics (form, size, and motility). These flagellates were not cultured, and their identification was confirmed by microscopic examination of an empyema fluid smear. Samples were mixed with whole blood at 1:3, spread onto glass slides, air dried, methanol fixed, and stained with Giemsa stain (Fig. 1A and B). Some aliquots of empyema fluid were stored at Ϫ20°C for molecular analysis. Bacteriological cultures of the fluid were performed for aerobic and anaerobic microorganisms, yielding Staphylococcus auricularis, but no bacilli were identified until after PCR sequencing of an empyema fluid sample. A Prevotella species was demonstrated by using universal primers for the 16S rRNA gene (1). Antibiotic therapy with metronidazole and piperacillin-tazobactam was administered.Case 2 is that of a 33-year-old man from Mexico City with a history of smoking and alcohol consumption who was admitted to the hospital with a 2-week nonproductive cough and chills, dyspnea, and left pleural chest pain. His blood pressure was 70/40 mmHg, his heart rate was 150 beats/min, and his respiratory rate was 40 breaths/min. During subsequent days, fever and diaphoresis were added to the clinical course, as well as worsening of dyspnea until he developed acute respiratory failure and septic shock. Thorax auscultation revealed bilateral crackles and diminished breath sounds on the left side; he was placed on mechanical ventilation. A chest X-ray and a thorax CT scan showed a right pneumothorax and left pleural effusion. He underwent bilater...