Department of Clinical Infectious Diseases, School of Medicine, Showa University, Tokyo, Japan.
J Infect Chemother. 2010 Feb;16(1):45-8. doi: 10.1007/s10156-009-0004-5.
A 79-year-old man consulted us because of left chest pain and fever ranging from 38.0 to 38.9 °C. A chest computed tomography scan showed a mass lesion (φ40 mm) in the left lingular segment, and inflammatory markers were elevated. He was admitted with a diagnosis of lung abscess, and panipenem/betamipron was administered at a dose of 2 g/day, after which the symptoms showed slight transient resolution. However, his body temperature increased again, to more than 39.0 °C, on the eighth day of hospitalization, and a chest radiograph suggested pleuritis as a complication. The antibiotics were changed to teicoplanin (TEIC; 400 mg/day) and meropenem (2.0 g/day). Thoracic drainage and pleural lavage were initiated at the same time. Lactobacillus spp. was detected from the pleural effusion by culture and was considered to be the causative organism, and it was resistant to TEIC. Therefore, the antibiotic was changed, to clindamycin, to which the bacteria was susceptible. No subsequent fever or pleural fluid retention was observed. The patient’s course was good, and he was discharged on day 45 of hospitalization. Subsequently, the causative organism was identified as Lactobacillus rhamnosus by the 16s rRNA sequence. Lactobacillus rhamnosus is rarely pathogenic in humans. Lactobacillus rhamnosus infection mostly occurs in immunosuppressed patients, and only a few cases have been reported in immunocompetent patients. In the present case, the patient was not immunodeficient; however, his lung had an impaired local immunosystem, due to emphysema.
一位 79 岁男性因左侧胸痛和 38.0 至 38.9°C 的发热来诊。胸部 CT 扫描显示左舌段有一肿块病变（φ40mm），炎症标志物升高。他被诊断为肺脓肿入院，给予帕尼培南/倍他米隆 2g/天治疗，症状稍有短暂缓解。然而，住院第 8 天他的体温再次升高至 39.0°C 以上，胸部 X 线片提示并发胸膜炎。将抗生素更换为替考拉宁（TEIC；400mg/天）和美罗培南（2.0g/天）。同时开始进行胸腔引流和胸腔灌洗。通过培养从胸腔积液中检测到乳杆菌属，并认为其是致病微生物，对 TEIC 耐药。因此，将抗生素更换为克林霉素，该菌对克林霉素敏感。未再出现发热或胸腔积液潴留。患者病情良好，住院第 45 天出院。随后，通过 16s rRNA 序列鉴定出致病微生物为鼠李糖乳杆菌。人源乳杆菌属很少具有致病性。乳杆菌属感染多发生于免疫抑制患者，免疫功能正常的患者仅报道过少数病例。在本病例中，患者无免疫缺陷；然而，由于肺气肿，他的肺部存在局部免疫功能受损。
