Right-sided infective endocarditis is less common than left-sided endocarditis and can be a difficult clinical diagnosis. The presence of intracardiac devices is a major risk factor. The presentation is less clear than left-sided forms because of the presence of respiratory symptoms and the absence of systemic embolization. Pylephlebitis, or septic thrombosis of the portal vein, is a serious infectious condition that often delays diagnosis. It is a complication of intraabdominal or pelvic infections. Streptococcus gallolyticus (S. gallolyticus) can cause infective endocarditis and is associated with colon neoplasia and hepatobiliary disease. In this case report, we describe the case of a 76-year-old male with a history of rectal adenocarcinoma who presented with different episodes of fever of unknown origin (FUO), one of which occurred after pacemaker implantation. Ultimately, he was diagnosed with S. gallolyticus-mediated tricuspid valve endocarditis with underlying pylephlebitis. Investigations did not show evidence of pacemaker lead endocarditis.

This study aimed to describe the incidence of Streptococcus bovis/Streptococcus equinus complex (SBSEC) bacteremia, distribution of the SBSEC subspecies, and their respective association with colorectal cancer (CRC). A population-based retrospective cohort study of all episodes of SBSEC-bacteremia from 2003 to 2018 in Skåne Region, Sweden. Subspecies was determined by whole-genome sequencing. Medical charts were reviewed. The association between subspecies and CRC were analysed using logistic regression. In total 266 episodes of SBSEC-bacteremia were identified and the average annual incidence was 2.0 per 100 000 inhabitants. Of the 236 isolates available for typing, the most common subspecies was S. gallolyticus subsp. pasteurianus 88/236 (37%) followed by S. gallolyticus subsp. gallolyticus 58/236 (25%). In order to determine the risk of cancer following bacteremia, an incidence cohort of 174 episodes without a prior diagnosis of CRC or metastasised cancer was followed for 560 person-years. CRC was found in 13/174 (7%), of which 9 (69%) had S. gallolyticus subsp. gallolyticus-bacteremia. In contrast to other European studies, S. gallolyticus subsp. pasteurianus was the most common cause of SBSEC-bacteremia. CRC diagnosis after bacteremia was strongly associated with S. gallolyticus subsp. gallolyticus-bacteremia. Identification of SBSEC subspecies can guide clinical decision-making regarding CRC work-up following bacteremia.

BACKGROUND: Streptococcus gallolyticus subspecies pasteurianus (SGP), a subtype of Streptococcus bovis , is an uncommon but important cause of neonatal sepsis. Although uncommon, SGP infections during infancy have been associated with an increased risk of morbidity and mortality.
METHODS: This is a systematic review and meta-analysis of available literature on the clinical course and outcomes of infants with SGP infection. Studies were identified using the following MeSH keywords: \" Streptococcus gallolyticus ,\" \" Streptococcus bovis ,\" \"newborn\" and \"infant.\" Data including perinatal factors, clinical presentation, investigations, treatment and outcomes were extracted and analyzed.
RESULTS: A total of 46 articles were identified (116 cases: 60 S. bovis , 56 SGP). The cases were predominantly term (52%), male (57%) and born via vaginal delivery (67%). The most common symptom was fever [67% (95% confidence interval (CI): 43%-84%)], lethargy [66% (95% CI: 32%-89%)], tachypnea [59% (95% CI: 27%-85%)] and irritability [59% (95% CI: 34%-79%)]. Infants with early-onset infections (<3 days of life) were more likely to have respiratory symptoms and bacteremia (73%), whereas late-onset infections presented predominantly with gastrointestinal symptoms. Four mortalities were reported which occurred before antibiotic administration. Isolated bacteria were mostly penicillin-susceptible [95% (95% CI: 78-99%)] and cases treated with penicillin derivative had good recovery.
CONCLUSIONS: SGP is an important cause of neonatal sepsis and meningitis. Penicillin derivative is an effective treatment for SGP, and outcomes appear to be favorable.

暂无摘要。

Infective endocarditis (IE) is a life-threatening condition often associated with various complications. A unique subset of IE cases involves the Streptococcus gallolyticus group, which has a well-documented but sometimes poorly understood association with colonic neoplasms. Specifically, colon cancer has a well-established association with IE caused by S. gallolyticus subspecies (spp.) gallolyticus. However, finding colon cancer in cases of IE due to S. gallolyticus spp. pasteurianus is rather unexpected. Herein, we present a rare instance of IE caused by S. gallolyticus spp. pasteurianus in a 62-year-old male, which led to the discovery of an underlying colorectal carcinoma. Considering the overall elevated risk of colon cancer in patients with endocarditis and in patients with S. bovis/S. equinus complex (SBSEC) bacteremia, we decided to proceed to colonoscopy, which revealed adenocarcinoma. The patient was administered a targeted antibiotic regimen and underwent a successful surgical resection, followed by valve replacement surgery. The outcome of this case supports the recommendation of routine colonoscopic evaluation in patients diagnosed with S. gallolyticus bacteremia, including those with subspecies pasteurianus, particularly when there are other associated findings. It strengthens the argument for conducting a colonoscopy in individuals diagnosed with SBSEC endocarditis, while carefully considering the specifics of each clinical situation. Our report highlights the need for heightened clinical vigilance and an integrated approach to treatment in similar cases.

As a potent, pleiotropic regulatory protein in Gram-positive bacteria, catabolite control protein A (CcpA) mediates the transcriptional control of carbohydrate metabolism in Streptococcus bovis, a lactate-producing bacterium that plays an essential role in rumen acidosis in dairy cows. Although the rumen uptake of carbohydrates is multi-substrate, the focus of S. bovis research thus far has been on the glucose. With the aid of gene deletion, whole-genome sequencing, and transcriptomics, we have unraveled the role of CcpA in carbohydrate metabolism, on the one hand, and acidosis, on the other, and we show that the S. bovis strain S1 encodes \"Carbohydrate-Active Enzymes\" and that ccpA deletion slows the organism\'s growth rate and modulates the organic acid fermentation pathways toward lower lactate, higher formate, and acetate in the maltose and cellobiose. Furthermore, this study revealed the different regulatory functions of the CcpA protein in rumen metabolism and acidosis.IMPORTANCEThis study is important as it illustrates the varying regulatory role of the Streptococcus bovis catabolite control protein A protein in carbohydrate metabolism and the onset of acidosis in dairy cattle.

OBJECTIVE: To develop an in-house matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) library for improved identification of species and subspecies of the Streptococcus bovis/Streptococcus equinus-complex (SBSEC).
METHODS: A total of 236 SBSEC isolates from blood stream infections and culture collections, determined by whole genome sequencing to subspecies level, were grown in brain heart infusion broth. Mass spectra were collected using the Bruker MALDI Biotyper system after ethanol-formic acid extraction. Main spectral profiles from 117 isolates were used to create the \"SBSEC-CMRS library.\" The remaining 119 spectra were used for evaluation of Bruker MALDI Biotyper (MBT) Compass Library Revision K (2022) and the SBSEC-CMRS library.
RESULTS: The Bruker library correctly identified species and subspecies in 72 of 119 (61 %) isolates, while the SBSEC-CMRS library identified 116 of 119 (97 %), using a cutoff score of ≥2.0.
CONCLUSIONS: The SBSEC-CMRS library showed sufficient diagnostic accuracy, and can be implemented in clinical practice for SBSEC species and subspecies identification.

Streptococcus bovis/equinus complex (SBSEC) is one of the most important lactic acid-producing rumen bacteria causing subacute ruminal acidosis. Despite the significance of the ruminal bacteria, lytic bacteriophages (phages) capable of infecting SBSEC in the rumen have been rarely characterized. Hence, we describe the biological and genomic characteristics of two lytic phages (designated as vB_SbRt-pBovineB21 and vB_SbRt-pBovineS21) infecting various SBSEC species, including the newly reported S. ruminicola. The isolated SBSEC phages were morphologically similar to Podoviridae and could infect other genera of lactic acid-producing bacteria, including Lactococcus and Lactobacillus. Additionally, they showed high thermal- and pH-stability, and those characteristics induce strong adaptation to the ruminal environment, such as the low pH found in subacute ruminal acidosis. Genome-based phylogeny revealed that both phages were related to Streptococcus phage C1 in the Fischettivirus. However, they had a lower nucleotide similarity and distinct genomic arrangements than phage C1. The phage bacteriolytic activity was evaluated using S. ruminicola, and the phages efficiently inhibited planktonic bacterial growth. Moreover, both phages could prevent bacterial biofilms of various SBSEC strains and other lactic acid-producing bacteria in vitro. Thus, the newly isolated two SBSEC phages were classified as new Fischettivirus members and could be considered as potential biocontrol agents against ruminal SBSEC bacteria and their biofilms.

Bacterial meningitis is a life-threatening condition that is mainly caused by Streptococcus pneumoniae and Neisseria meningitis. Although Streptococcus gallolyticus subsp. pasteurianus (Sgp) is also known to cause meningitis, its frequency is quite low, especially in adults. We herein report the first immunocompetent Japanese adult patient (20-year-old woman) with bacterial meningitis caused by Sgp. The patient showed dramatic improvement after antibiotic treatment. Although previous reports have described an association between Sgp infection and an immunosuppressive status, bowel and hepatobiliary diseases, or strongyloidiasis, our case did not demonstrate any of these conditions, suggesting that Sgp can cause meningitis even in young immunocompetent adults.

Whether cirrhotic patients with Streptococcus bovis bacteremia have an increased risk of colorectal neoplasm is uncertain. A multicentric retrospective cohort study was conducted investigating associations between S. bovis biotype and species, cirrhosis, and colorectal neoplasm. Out of 779 patients with S. bovis bacteremia, 69 (8.7%) had cirrhosis. No differences were found in the prevalence of colorectal neoplasm between cirrhotic and non-cirrhotic patients undergoing colonoscopy. Among cirrhotic patients, prevalence of colorectal neoplasms was higher in S. bovis biotype I (S. gallolyticus) bacteremia (80%) than in S. bovis biotype II (33.3%; p < 0.007). In conclusion, risk of colorectal neoplasm is high among cirrhotic patients with S. gallolyticus bacteremia.