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Lung disease is the leading cause of morbidity and mortality in cystic fibrosis (CF) patients. A modest number of bacterial pathogens have been correlated with pulmonary function decline; however, microbiological and molecular evidence suggests that CF airway infection is polymicrobial. To obtain a more complete assessment of the microbial community composition and dynamics, we undertook a longitudinal study by using culture-independent and microbiological approaches. In the process, we demonstrated that within complex and dynamic communities, the Streptococcus milleri group (SMG) can establish chronic pulmonary infections and at the onset of 39% of acute pulmonary exacerbations, SMG is the numerically dominant pathogen. We report the comprehensive polymicrobial community dynamics of a CF lung infection in a clinically relevant context. If a given organism, such as Pseudomonas aeruginosa, becomes resistant to antibiotic therapy, an alternative treatment avenue may mediate the desired clinical response by effectively managing the composition of the microbial community.

The purpose of this investigation was to provide a comprehensive review of the pathogenic role and spectrum of disease of milleri group streptococci, with special attention to bloodstream invasion and to possible differential roles among the three species. All consecutive isolates of milleri group streptococci from any anatomic source, during a 37-month period, in a tertiary care teaching hospital in Tel-Aviv, Israel, were thoroughly investigated. Identification to the species level was performed by an automated system. Streptococcus anginosus constituted 82% of the 245 patient-unique isolates from hospitalized patients. All nonurinary isolates were involved in pyogenic infections mostly originating from the gastrointestinal tract, with bacteremia in 28 cases. The 71 urinary isolates represented either urinary tract infection or nonsignificant bacteriuria. No specific association could be detected between species and the infection site, except for a higher relative representation of Streptococcus constellatus in bacteremia. Milleri group streptococci are common in clinical practice and play a different pathogenic role to other viridans streptococci. Due to their invariable association with pyogenic processes, their presence in blood warrants immediate focus identification. In addition, they have a previously unappreciated clinical niche concerning urinary tract infection. The identification of viridans streptococci to the species level is of paramount clinical significance.

. Streptococcus constellatus are opportunistic microorganisms. When immunocompromised patients with concomitant systemic diseases are infected with S.constellatus, the bacteria may cause sepsis. A patient was admitted to hospital due to septic shock and multi-organ dysfunction in the course of neck phlegmon. The microbiological system identified S. constellatus in the patient who worked as a dog groomer. These facts confirmed that this aetiological factor may have caused such a serious infection because S. constellatus is a bacterial species found in dogs. It is most likely that the bacteria colonised the patient. Zoonotic transmission of microorganisms is particularly important for the development of infections in dogs and humans. Knowledge about how to treat deep cervical infections is necessary in the daily practice of a maxillofacial surgeon. The right antibiotic can applied only when the strain causing the infection has been identified.

Background 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. Methods 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. Results 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. Conclusions 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 .

Background Dental caries and periodontal disease are the commonest bacterial diseases of man and can result in tooth loss. The principal method of prevention is the mechanical removal of dental plaque augmented by active agents incorporated into toothpastes and mouthrinses. In-vitro assays that include complex oral bacterial biofilms are required to accurately predict the efficacy of novel active agents in vivo . The aim of this study was to develop an oral biofilm model using the Calgary biofilm device (CBD) seeded with a natural saliva inoculum and analysed by next generation sequencing. The specific objectives were to determine the reproducibility and stability of the model by comparing the composition of the biofilms over time derived from (i) the same volunteers at different time points, and (ii) different panels of volunteers. Results Pyrosequencing yielded 280,093 sequences with a mean length of 432 bases after filtering. A mean of 320 and 250 OTUs were detected in pooled saliva and biofilm samples, respectively. Principal coordinates analysis (PCoA) plots based on community membership and structure showed that replicate biofilm samples were highly similar and clustered together. In addition, there were no significant differences between biofilms derived from the same panel at different times using analysis of molecular variance (AMOVA). There were significant differences between biofilms from different panels (AMOVA, P  < 0.002). PCoA revealed that there was a shift in biofilm composition between seven and 14 days (AMOVA , P  < 0.001). Veillonella parvula , Veillonella atypica / dispar / parvula and Peptostreptococcus stomatis were the predominant OTUs detected in seven-day biofilms, whilst Prevotella oralis , V. parvula and Streptococcus constellatus were predominant in 14-day biofilms. Conclusions Diverse oral biofilms were successfully grown and maintained using the CBD. Biofilms derived from the same panel of volunteers were highly reproducible. This model could be used to screen both antimicrobial-containing oral care products and also novel approaches aiming to modify plaque composition, such as pre- or probiotics.

Streptococcal Species is increasingly recognized as a potentially preventable emerging infection in human’s brain with high prevalence around the world. Streptococcus constellatus is one of the most common pathogens. Meanwhile, anaerobic bacteria are the rare causes for intracranial infection. To date, intracranial mixed infection caused by Prevotella intermedia and Streptococcus constellatus has not been reported. We reported a Chinese case to raise the global awareness of severity of the intracranial mixed infection. Here, we illustrated the epidemiological risk factors, clinical manifestations and outcomes of the patient. For patients who suffer from exacerbated brain infection with fetid cerebrospinal fluid, early repeated imaging is urgently needed and empiric antibiotic therapy should consider anaerobic and aerobic bacteria in these situations.

The aim of this study was to establish an identification method for the anginosus group within the genus Streptococcus by polymerase chain reaction (PCR). Using a primer pair based on the group-specific sequences of penicillin-binding protein 2B ( pbp2b) gene, a 275-bp fragment was amplified from each species in the group but no size-matched products were obtained in other streptococci. Further identification in the species or subspecies level was possible by a multiplex PCR with primers for the 16S ribosomal RNA gene of Streptococcus anginosus, the hyaluronate lyase genes both of Streptococcus intermedius and Streptococcus constellatus subsp. constellatus, and the intermedilysin ( ily) gene of S. intermedius. In the case of Streptococcus constellatus subsp. pharyngis, the amplified fragment from the S. intermedius-type hyaluronate lyase gene was obtained, while that from the ily gene was not. These results also indicate that two different hyaluronate lyase genes are distributed among the anginosus group.

The terminology and classification of the Anginosus group streptococci has been inconsistent. We tested the utility of 16S rRNA gene and tuf gene sequencing and conventional biochemical tests for the reliable differentiation of the Anginosus group streptococci. Biochemical testing included Rapid ID 32 Strep, API Strep, Fluo-Card Milleri, Wee-tabs, and Lancefield antigen typing. Altogether, 61 Anginosus group isolates from skin and soft tissue infections and four reference strains were included. Our results showed a good agreement between 16S rRNA gene and tuf gene sequencing. Using the full sequence was less discriminatory than using the first part of the 16S rRNA gene. The three species could not be separated with the API 20 Strep test. Streptococcus intermedius could be differentiated from the other two species by β-galactosidase (ONPG) and β-N-acetyl-glucosaminidase reactions. Rapid ID 32 Strep β-glucosidase reaction was useful in separating S. anginosus strains from S. constellatus. In conclusion, both 16S rRNA gene and tuf gene sequencing can be used for the reliable identification of the Anginosus group streptococci. S. intermedius can be readily differentiated from the other two species by phenotypic tests; however, 16S rRNA gene or tuf gene sequencing may be needed for separating some strains of S. constellatus from S. anginosus.

Pyomyositis is an uncommon primary bacterial infection of skeletal muscles, usually caused by Staphylococcus aureus. Predisposing factors for pyomyositisinclude immunodeficiency, trauma, injection drug use, concurrent infection and malnutrition. The diagnosis, staging of the disease and differential diagnosis are established by ultrasound, CT and MRI. Treatment involves surgical drainage and antibiotic therapy. We report a case of abdominal rectus muscle pyomyositis, which constitutes, as far as we know, thesecond reported in bibliography, while Prevotella disiens is firstly reported as causative agent.

Subdural empyema related to Streptococcus constellatus is extremely rare in an immunocompetent child, and also there is no reported case along with Staphylococcus lugdunensis infection. Although Streptococcus constellatus has been determined as a co-pathogen with anerobic bacteria in many infections, it has not been reported in combination with Staphylococcus lugdunensis. The authors describe a case of previously healthy 16-y-old child with unilateral subdural empyema due to these bacteria. Sinusitis was the only predisposing factor in the index case. The authors propose that some cases of culture-negative intracranial infections may be due to these infectious agents. Therefore, these agents should be considered as causes of intracranial infection in persistent complaints such as fever and headache after sinusitis in children. It is important to treat them with effective antibiotics and early surgical intervention for favorable outcome, because fatal cases were reported due to Streptococcus constellatus infections.