Abstract：
Legionella pneumophila serogroup (SG) 1, the main cause of Legionnaires\' disease, can be diagnosed using urinary antigen testing kits. However, lower respiratory tract specimen cultures are required to identify L. pneumophila SG 2-15. We attempted to detect L. pneumophila SG-specific genes in a culture-negative sputum specimen from a patient with pneumonia who was suspected to have Legionnaires\' disease. Two multiplex PCR methods targeting L. pneumophila were modified and amplicons considered to be SG13 specific were detected. Direct sequencing revealed that the amplicons were identical to the nucleotide sequence of L. pneumophila SG13. Based on the presentation and clinical course (fever, muscle pain, disturbance of consciousness, high C-reactive protein titer, rhabdomyolysis, hypophosphatemia, and symptomatic improvement with levofloxacin treatment), in combination with the detection of L. pneumophila SG-specific genes, we suspected L. pneumophila SG13 pneumonia. L. pneumophila non-SG1 pneumonia is thought to be underestimated because of its difficult laboratory diagnosis. The modified multiplex PCR system for lower respiratory tract specimens revealed in this study is likely to improve the diagnosis of Legionnaires\' disease caused by L. pneumophila SG13 and other SGs.
摘要：
嗜肺军团菌血清群（SG）1，军团菌病的主要原因，可以用尿抗原检测试剂盒诊断;然而，下呼吸道标本培养是鉴定嗜肺乳杆菌SG2-15所必需的。我们试图在一名怀疑患有军团病的肺炎患者的培养阴性痰标本中检测嗜肺乳杆菌SG特异性基因。对靶向嗜肺乳杆菌的两种多重PCR方法进行了修饰，并检测了被认为是SG13特异性的扩增子。直接测序显示扩增子与嗜肺乳杆菌SG13的核苷酸序列相同。根据临床表现和临床病程(发烧，肌肉疼痛，意识障碍,高C反应蛋白滴度，横纹肌溶解症,低磷酸盐血症,以及左氧氟沙星治疗的症状改善）结合肺炎支原体SG特异性基因的检测，我们怀疑嗜肺菌SG13肺炎。由于难以进行实验室诊断，因此认为肺炎支原体非SG1肺炎被低估了。本研究中显示的改良的下呼吸道标本多重PCR系统可能会增加由嗜肺乳杆菌SG13和其他SGs引起的军团病的诊断。
