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The ISME Journal May 2019Bacterial vaginosis (BV) is characterized by a highly structured polymicrobial biofilm, which is strongly adhered to the vaginal epithelium and primarily consists of the...
Bacterial vaginosis (BV) is characterized by a highly structured polymicrobial biofilm, which is strongly adhered to the vaginal epithelium and primarily consists of the bacterium Gardnerella vaginalis. However, despite the presence of other BV-associated bacteria, little is known regarding the impact of other species on BV development. To gain insight into BV progress, we analyzed the ecological interactions between G. vaginalis and 15 BV-associated microorganisms using a dual-species biofilm model. Bacterial populations were quantified using a validated peptide nucleic acid fluorescence in situ hybridization approach. Furthermore, biofilm structure was analyzed by confocal laser scanning microscopy. In addition, bacterial coaggregation ability was determined as well as the expression of key virulence genes. Remarkably, our results revealed distinct biofilm structures between each bacterial consortium, leading to at least three unique dual-species biofilm morphotypes. Furthermore, our transcriptomic findings seem to indicate that Enterococcus faecalis and Actinomyces neuii had a higher impact on the enhancement of G. vaginalis virulence, while the other tested species had a lower or no impact on G. vaginalis virulence. This study casts a new light on how BV-associated species can modulate the virulence aspects of G. vaginalis, contributing to a better understanding of the development of BV-associated biofilms.
Topics: Bacterial Proteins; Biofilms; Enterococcus faecalis; Female; Gardnerella vaginalis; Humans; In Situ Hybridization, Fluorescence; Microbiota; Vagina; Vaginosis, Bacterial; Virulence Factors
PubMed: 30670827
DOI: 10.1038/s41396-018-0337-0 -
Journal of Infection and Public Health 2019Actinomycosis is a rare infection in patients younger than 10years of age. It mainly affects the cervicofacial region, but many other sites of infection have been...
Actinomycosis is a rare infection in patients younger than 10years of age. It mainly affects the cervicofacial region, but many other sites of infection have been recognized. About 70% of infections are due to either Actinomyces israelii or Actinomyces gerencseriae. Actinomyces neuii was first described in 1985 in two patients with post cataract endophthalmitis, A. neuii represents 17% of clinical Actinomyces isolates. Several reports indicated a well-known association between Actinomyces infections and Intrauterine devices (IUD). We are reporting a case of neonatal sepsis due to A. neuii as a first case reported from Saudi Arabia. It was thought to be the cause of the premature labor and neonatal sepsis. The prevalence of Actinomyces infection is likely underestimated and additional premature labors and abortions could have been caused by Actinomyces infections that were never detected. More studies are needed to confirm the association of maternal Actinomyces infections with preterm labor.
Topics: Actinomyces; Actinomycosis; Adult; Female; Humans; Infant, Newborn; Neonatal Sepsis; Obstetric Labor, Premature; Pregnancy; Saudi Arabia
PubMed: 29706318
DOI: 10.1016/j.jiph.2018.04.001 -
IDCases 2017Actinomycosis is a slowly progressive infection caused by anaerobic bacteria, primarily from the genus . Primary actinomycosis of the breast is rare and presents as a...
Actinomycosis is a slowly progressive infection caused by anaerobic bacteria, primarily from the genus . Primary actinomycosis of the breast is rare and presents as a mass like density which can mimic malignancy. Mammography, ultrasonography and histopathologic examination is required for diagnosis. Treatment should consist of high doses of antibacterials for a prolonged period of time and possibly surgical drainage. Primary actinomycosis infections are commonly caused by . is a less common cause of classical actinomycosis. We present two cases of primary actinomycosis of the breast in two female patients caused by
PubMed: 28462153
DOI: 10.1016/j.idcr.2017.03.014 -
Journal of Clinical Microbiology Dec 2016Commensal bacteria from the skin and mucosal surfaces are routinely isolated from patient samples and considered contaminants. The majority of these isolates are...
Commensal bacteria from the skin and mucosal surfaces are routinely isolated from patient samples and considered contaminants. The majority of these isolates are catalase-positive Gram-positive rods from multiple genera routinely classified as diphtheroids. These organisms can be seen upon Gram staining of clinical specimens or can be isolated as the predominant or pure species in culture, raising a priori suspicion of a possible involvement in infection. With the development and adoption of matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS), suspicious isolates are now routinely identified to the species level. In this study, we performed a retrospective data review (2012 to 2015) and utilized site-specific laboratory criteria and chart reviews to identify species within the diphtheroid classification representative of true infection versus contamination. Our data set included 762 isolates from 13 genera constituting 41 bacterial species. Only 18% represented true infection, and 82% were deemed contaminants. Clinically significant isolates were identified in anaerobic wounds (18%), aerobic wounds (30%), blood (5.5%), urine (22%), cerebrospinal fluid (24%), ophthalmologic cultures (8%), and sterile sites (20%). Organisms deemed clinically significant included multiple Actinomyces species in wounds, Propionibacterium species in joints and cerebrospinal fluid associated with central nervous system hardware, Corynebacterium kroppenstedtii (100%) in breast, and Corynebacterium striatum in multiple sites. Novel findings include clinically significant urinary tract infections by Actinomyces neuii (21%) and Corynebacterium aurimucosum (21%). Taken together, these findings indicate that species-level identification of diphtheroids isolated with a priori suspicion of infection is essential to accurately determine whether an isolate belongs to a species associated with specific types of infection.
Topics: Gram-Positive Rods; Humans; Molecular Typing; Mucous Membrane; RNA, Ribosomal, 16S; Retrospective Studies; Sequence Analysis, DNA; Skin; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization
PubMed: 27629905
DOI: 10.1128/JCM.01393-16 -
The Canadian Journal of Infectious... 2016Background. Actinomyces neuii is a Gram-positive bacillus rarely implicated in human infections. However, its occurrence is being increasingly recognized with the use of... (Review)
Review
Background. Actinomyces neuii is a Gram-positive bacillus rarely implicated in human infections. However, its occurrence is being increasingly recognized with the use of improved identification systems. Objective. To analyse A. neuii infections in Alberta, Canada, and review the literature regarding this unusual pathogen. Methods. Cases of A. neuii were identified in 2013-2014 in Alberta. Samples were cultured aerobically and anaerobically. A predominant catalase positive Gram-positive coryneform bacillus with no branching was isolated in each case. Testing was initially done with API-CORYNE® (bioMérieux) and isolates were sent to the Provincial Laboratory for Public Health for further testing. Isolates' identities were confirmed by matrix-assisted laser desorption ionization time-of-flight mass spectrometry microbial identification system (MALDI-TOF MS MIS; bioMérieux) and/or DNA sequencing. Results. Six cases of A. neuii infection were identified. All patients had soft tissue infections; typically, incision and drainage were done followed by a course of antibiotics. Agents used included cephalexin, ertapenem, ciprofloxacin, and clindamycin. All had favourable outcomes. Conclusions. While A. neuii is infrequently recognized, it can cause a diverse array of infections. Increased use of MALDI-TOF MS MIS is leading to increased detection; thus, understanding the pathogenicity of this bacterium and its typical susceptibility profile will aid clinical decision-making.
PubMed: 27366175
DOI: 10.1155/2016/6017605 -
International Journal of Infectious... Jun 2015Breast implant infections are usually caused by Staphylococcus aureus and coagulase-negative staphylococci. Gram-negative bacilli are rarely reported to be involved in...
BACKGROUND
Breast implant infections are usually caused by Staphylococcus aureus and coagulase-negative staphylococci. Gram-negative bacilli are rarely reported to be involved in breast implant infections.
METHODS
Thirty-seven cases of microbiologically confirmed breast implant infection managed from January 2008 to June 2012 in the study centre were reviewed, including 10 cases from the study centre itself and 27 cases from private clinics in the region.
RESULTS
The prevalence of breast implant infection in the study centre was 0.74% of breast implantation, i.e., 3.23% in breast reconstruction for breast cancer and 0.27% in aesthetic breast augmentation (p=0.0002). Of the 37 cases, 30% had undergone radiotherapy and 11% had undergone a lymph node dissection. S. aureus was identified in 18 cases, Gram-negative bacilli in 10 cases, coagulase-negative staphylococci in eight cases, anaerobic bacteria in eight cases, and streptococci in three cases. Pseudomonas aeruginosa was the second most commonly identified pathogen. Staphylococcus epidermidis was the most frequent coagulase-negative Staphylococcus species. In addition to Propionibacterium acnes and Actinomyces neuii, other facultative and strict anaerobic bacteria have not been reported before, e.g., Bacteroides thetaiotaomicron, Corynebacterium simulans, Dermabacter hominis, Finegoldia magna, and Peptoniphilus harei. Seventy-percent of cases were treated by immediate implant removal. All cases treated only with antibiotics were treated with surgery at the second visit.
CONCLUSIONS
The microbiological epidemiology was noted by an increasing the proportion of Gram-negative bacteria and anaerobic bacteria detected with the advent of MALDI-TOF MS and molecular identification for diagnosis.
Topics: Adult; Aged; Bacteria; Bacterial Infections; Breast Diseases; Breast Implants; Female; France; Gram-Negative Bacteria; Humans; Mammaplasty; Middle Aged; Postoperative Complications; Pseudomonas aeruginosa; Referral and Consultation; Staphylococcus; Staphylococcus aureus; Young Adult
PubMed: 25910855
DOI: 10.1016/j.ijid.2015.04.010 -
Clinical Microbiology Reviews Apr 2015Actinomyces israelii has long been recognized as a causative agent of actinomycosis. During the past 3 decades, a large number of novel Actinomyces species have been... (Review)
Review
Actinomyces israelii has long been recognized as a causative agent of actinomycosis. During the past 3 decades, a large number of novel Actinomyces species have been described. Their detection and identification in clinical microbiology laboratories and recognition as pathogens in clinical settings can be challenging. With the introduction of advanced molecular methods, knowledge about their clinical relevance is gradually increasing, and the spectrum of diseases associated with Actinomyces and Actinomyces-like organisms is widening accordingly; for example, Actinomyces meyeri, Actinomyces neuii, and Actinomyces turicensis as well as Actinotignum (formerly Actinobaculum) schaalii are emerging as important causes of specific infections at various body sites. In the present review, we have gathered this information to provide a comprehensive and microbiologically consistent overview of the significance of Actinomyces and some closely related taxa in human infections.
Topics: Actinomyces; Actinomycosis; Anti-Bacterial Agents; Bacterial Typing Techniques; Classification; Humans; Microbial Sensitivity Tests
PubMed: 25788515
DOI: 10.1128/CMR.00100-14 -
Peritoneal Dialysis International :... 2014
Topics: Actinomyces; Aged, 80 and over; Anti-Bacterial Agents; Device Removal; Drug Therapy, Combination; Female; Follow-Up Studies; Humans; Infusions, Parenteral; Peritoneal Dialysis, Continuous Ambulatory; Peritonitis; Rare Diseases; Treatment Outcome
PubMed: 25520492
DOI: 10.3747/pdi.2013.00146