连云港市第一人民医院于2024年5月28日收治1例37岁男性“肺部感染”患者。该患者于16 d前体检发现左肺下叶稍高密度影。门诊给予头孢唑肟、左氧氟沙星（剂量不详）抗感染治疗9 d后，复查胸部CT示两肺感染较前进展。患者入院后行气管镜检查，肺泡灌洗液高通量测序（NGS）结果示口腔毛滴虫序列522条。患者有牙周病史，2个月内曾使用夹生肉的筷子进食。结合患者病史和辅助检查结果，诊断为口腔毛滴虫感染合并肺部感染。给予比阿培南（0.3 g/次，3次/d）和甲硝唑（0.5 g/次，3次/d）治疗9 d，复查肺部CT提示肺部感染好转，无其他特殊异常遂出院。出院后继续口服莫西沙星（0.4 g/次，1次/d）与甲硝唑（0.5 g/次，3次/d），2周后门诊复诊，患者无不适，影像学示左肺清晰、右肺钙化灶，其余无明显异常。

A 37-year-old male patient with pulmonary infection was admitted to Lianyungang Municipal First People’s Hospital on May 28, 2024, and he had lightly high-density shadows in the lower lobe of the left lung during physical examinations 16 days ago. The case was given anti-infective therapy with cefazoxime and levofloxacin (unknown dosage) for 9 days, and chest CT scans displayed progression of infections in bilateral lungs. Following admission, the patient underwent tracheoscopy and next-generation sequencing (NGS) of alveolar lavage fluids identified 522 Trichomonas tenax sequences. The patient had a medical history of periodontal disease and had ingested food with chopsticks used for undercooked meat within the past 2 months. The patient was diagnosed with T. tenax infection complicated with asymptomatic pulmonary infection based on his medical history and auxiliary diagnoses, and was treated with biapenem (0.3 g, 3 times per day) and metronidazole (0.5 g, 3 times per day) for 9 days. Chest CT scans displayed improvements in pulmonary infections, and the case was discharged from hospital because of absence of any other special abnormalities. Following discharge, the patient continued to administer moxifloxacin (0.1 g per day) and metronidazole (0.5 g, 3 times per day) orally. Outpatient follow-up visits showed no discomfort two weeks following discharge, and chest CT scans displayed a clear left lung and calcification in the right lung, with no other obvious abnormalities found.