Skip to main content

01.12.2015 | Research article | Ausgabe 1/2015 Open Access

BMC Pulmonary Medicine 1/2015

The clinical features of respiratory infections caused by the Streptococcus anginosus group

BMC Pulmonary Medicine > Ausgabe 1/2015
Shingo Noguchi, Kazuhiro Yatera, Toshinori Kawanami, Kei Yamasaki, Keisuke Naito, Kentaro Akata, Ikuko Shimabukuro, Hiroshi Ishimoto, Chiharu Yoshii, Hiroshi Mukae
Wichtige Hinweise

Electronic supplementary material

The online version of this article (doi:10.​1186/​s12890-015-0128-6) contains supplementary material, which is available to authorized users.

Competing interests

Statements of interest: all authors declare no conflicts of interest.

Authors’ contributions

SN (designed experiments, data collection, performed data analysis, wrote the first draft), KYatera (designed experiments, performed data analysis, provided intellectual contributions), TK (data collection, provided intellectual contributions), KYamasaki (data collection, provided intellectual contributions), KN (data collection), KA (data collection), IS (data collection), HI (provided intellectual contributions), CY (provided intellectual contributions), HM (conceived & designed experiments, provided intellectual contributions). All authors read and approved the final version of the manuscript.



The Streptococcus anginosus group (SAG) play important roles in respiratory infections. It is ordinarily difficult to distinguish them from contaminations as the causative pathogens of respiratory infections because they are often cultured in respiratory specimens. Therefore, it is important to understand the clinical characteristics and laboratory findings of respiratory infections caused by the SAG members. The aim of this study is to clarify the role of the SAG bacteria in respiratory infections.


A total of 30 patients who were diagnosed with respiratory infections which were caused by the SAG bacteria between January 2005 and February 2015 were retrospectively evaluated.


Respiratory infections caused by the SAG were mostly seen in male patients with comorbid diseases and were typically complicated with pleural effusion. Pleural effusion was observed in 22 (73.3%) patients. Empyema was observed in half of the 22 patients with pleural effusion. S. intermedius, S. constellatus and S. anginosus were detected in 16 (53.3 %), 11 (36.7 %) and 3 (10.0 %) patients, respectively. Six patients had mixed-infections. The duration from the onset of symptoms to the hospital visit was significantly longer in “lung abscess” patients than in “pneumonia” patients among the 24 patients with single infections, but not among the six patients with mixed-infection. The peripheral white blood cell counts of the “pneumonia” patients were higher than those of the “lung abscess” patients and S. intermedius was identified significantly more frequently in patients with pulmonary and pleural infections (pneumonia and lung abscess) than in patients with bacterial pleurisy only. In addition, the patients in whom S. intermedius was cultured were significantly older than those in whom S. constellatus was cultured.


Respiratory infections caused by the SAG bacteria tended to be observed more frequently in male patients with comorbid diseases and to more frequently involve purulent formation. In addition, S. intermedius was mainly identified in elderly patients with having pulmonary infection complicated with pleural effusion, and the aspiration of oral secretions may be a risk factor in the formation of empyema thoracis associated with pneumonia due to S. intermedius.
Über diesen Artikel

Weitere Artikel der Ausgabe 1/2015

BMC Pulmonary Medicine 1/2015 Zur Ausgabe

Neu im Fachgebiet Innere Medizin

Mail Icon II Newsletter

Bestellen Sie unseren kostenlosen Newsletter Update Innere Medizin und bleiben Sie gut informiert – ganz bequem per eMail.

© Springer Medizin