Shingo Noguchi1, Kazuhiro Yatera2, Toshinori Kawanami3, Kazumasa Fukuda4, Kei Yamasaki5, Keisuke Naito6, Kentaro Akata7, Hiroshi Ishimoto8, Hiroshi Mukae9. 1. Department of Respiratory Medicine, Wakamatsu Hospital of the University of Occupational and Environmental Health, Japan, 1-17-1, Hamamachi, Wakamatsuku, Kitakyusyu city, Fukuoka 808-0024, Japan; Department of Respiratory Medicine, University of Occupational and Environmental Health, Japan, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu city, Fukuoka 807-8555, Japan. Electronic address: sn0920@med.uoeh-u.ac.jp. 2. Department of Respiratory Medicine, University of Occupational and Environmental Health, Japan, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu city, Fukuoka 807-8555, Japan. Electronic address: yatera@med.uoeh-u.ac.jp. 3. Department of Respiratory Medicine, University of Occupational and Environmental Health, Japan, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu city, Fukuoka 807-8555, Japan. Electronic address: namihei@med.uoeh-u.ac.jp. 4. Department of Microbiology, University of Occupational and Environmental Health, Japan, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu city, Fukuoka 807-8555, Japan. Electronic address: kfukuda@med.uoeh-u.ac.jp. 5. Department of Respiratory Medicine, University of Occupational and Environmental Health, Japan, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu city, Fukuoka 807-8555, Japan. Electronic address: yamasaki@med.uoeh-u.ac.jp. 6. Department of Respiratory Medicine, University of Occupational and Environmental Health, Japan, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu city, Fukuoka 807-8555, Japan. Electronic address: k-naito@med.uoeh-u.ac.jp. 7. Department of Respiratory Medicine, University of Occupational and Environmental Health, Japan, 1-1, Iseigaoka, Yahatanishiku, Kitakyushu city, Fukuoka 807-8555, Japan. Electronic address: kentarouakata@med.uoeh-u.ac.jp. 8. Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1, Sakamoto, Nagasaki city, Nagasaki 852-8501, Japan. Electronic address: h-ishimoto@nagasaki-u.ac.jp. 9. Department of Respiratory Medicine, Nagasaki University Graduate School of Biomedical Sciences, 1-7-1, Sakamoto, Nagasaki city, Nagasaki 852-8501, Japan. Electronic address: hmukae@nagasaki-u.ac.jp.
Abstract
BACKGROUND: Chlamydophila pneumoniae is a causative pathogen of lower respiratory tract infection, which generally infects healthy, young people. However, it is often difficult to evaluate acute C. pneumoniae infection using upper respiratory tract specimens and/or sputum samples due to its persistent infection or colonization. The interpretation of frequency of detection of C. pneumoniae seems to be insufficient in community-onset pneumonia. The aim of this study was to evaluate the presence of C. pneumoniae using bronchoalveolar lavage fluid (BALF) samples. METHODS: BALF samples from 147 patients with pneumonia were retrospectively evaluated using C. pneumoniae-specific polymerase chain reaction (PCR) primers. RESULTS: None of the samples had positive PCR results for C. pneumoniae using two different sets of specific primers. Single and paired serological analyses were performed in 54 (36.7%) and 37 (25.2%) patients, respectively. These analyses revealed that 1 of 37 (2.7%) patients had a presumptive acute infection with C. pneumoniae, 8 of the 54 (14.8%) patients were suspected of having a C. pneumoniae infection, and 7 of the 37 (18.9%) patients were suspected of having past C. pneumoniae infection. In addition, cultivation and/or 16S rRNA gene sequencing detected Haemophilus influenzae in the presumptive case using the serological method. CONCLUSIONS: The results of the present study revealed that C. pneumoniae might be a minor causative agent of community-onset pneumonia according to an evaluation of specimens obtained from the lower respiratory tract.
BACKGROUND: Chlamydophila pneumoniae is a causative pathogen of lower respiratory tract infection, which generally infects healthy, young people. However, it is often difficult to evaluate acute C. pneumoniae infection using upper respiratory tract specimens and/or sputum samples due to its persistent infection or colonization. The interpretation of frequency of detection of C. pneumoniae seems to be insufficient in community-onset pneumonia. The aim of this study was to evaluate the presence of C. pneumoniae using bronchoalveolar lavage fluid (BALF) samples. METHODS: BALF samples from 147 patients with pneumonia were retrospectively evaluated using C. pneumoniae-specific polymerase chain reaction (PCR) primers. RESULTS: None of the samples had positive PCR results for C. pneumoniae using two different sets of specific primers. Single and paired serological analyses were performed in 54 (36.7%) and 37 (25.2%) patients, respectively. These analyses revealed that 1 of 37 (2.7%) patients had a presumptive acute infection with C. pneumoniae, 8 of the 54 (14.8%) patients were suspected of having a C. pneumoniae infection, and 7 of the 37 (18.9%) patients were suspected of having past C. pneumoniae infection. In addition, cultivation and/or 16S rRNA gene sequencing detected Haemophilus influenzae in the presumptive case using the serological method. CONCLUSIONS: The results of the present study revealed that C. pneumoniae might be a minor causative agent of community-onset pneumonia according to an evaluation of specimens obtained from the lower respiratory tract.