Actinomyces Neuii Research Articles

Abstract Study question Does the endometrium possess alive, culturable bacteria, and are there any microbes associated with endometriosis? Summary answer Thirty-five cultured bacterial species were identified in the receptive-phase endometrium, and an endometriosis-specific bacterial profile was detected. What is known already Endometriosis is a chronic inflammatory disease and one of the most prevalent female reproductive disorders, but its etiology remains unknown. Recently, significant attention has been directed towards studying the endometrial microbiome and its potential correlation with endometriosis. These analyses typically employ 16S rRNA gene sequencing, which detects bacterial genera but does not distinguish whether the bacteria are alive and hasn’t provided conclusive results regarding endometrial microbiome composition. Our aim is to develop a culture-based method for identifying live microbes in the endometrium and identifying bacterial species associated with endometriosis. Study design, size, duration This pilot cross-sectional study recruited twenty women from couples prior to undergoing infertility treatment at the Reproductive Unit of Universitary Hospital Virgen de las Nieves (Granada) between 2020 and 2022. Ten women were diagnosed with active endometriosis (no treatment), while ten women had male factor infertility, serving as the control group in our study. Participants/materials, setting, methods Endometrial biopsies were obtained during the mid-secretory phase, 7-9 days after ovulation (assessed with a urinary LH test), using an endometrial curette device. The biopsies were snap-frozen and stored at -80 °C until analysis. Microbiota cultures were conducted for up to 30 days using nine different media under aerobic, microaerobic, and anaerobic conditions. Matrix-assisted laser desorption/ionization–time of flight mass spectrometry (MALDI-TOF MS) was utilized for bacterial isolate identification. Main results and the role of chance In total, 19 out of 20 patients (95%) tested positive for one or more microbes, with only 1 patient (5%) showing no microbial growth. We detected thirty-five bacterial species in these mid-secretory endometrial samples. Among them, fourteen bacterial species were common in both endometriosis and control samples, while five species—Bifidobacterium bifidum, Bifidobacterium breve, Cutibacterium avidum, Lactobacillus vaginalis, and Staphylococcus warneri—were exclusively cultured from endometriosis samples. Conversely, healthy samples harbored fourteen exclusive species, including Actinomyces neuii, Corynebacterium amycolatum, Enterococcus faecalis, and Finegoldia magna, among others. Control endometrial samples, altogether, possessed significantly more bacterial species than endometriosis samples (30 vs. 19 microbial species). These findings are consistent with the initial culturomics analyses of endometrial microbiota, highlighting the method’s efficacy in identifying isolates at the species level. Notably, species such as Actinotignum schaalii, Bifidobacterium dentium, Atopobium vaginae, and Rothia dentocariosa were identified in our samples, marking the first description of these species in endometrial culturomics studies. Among all participants, the bacteria with the highest colony forming units were Cutibacterium acnes, Lactobacillus jensenii, Lactobacillus crispatus, and Lactobacillus iners. Our study confirms the presence of the endometrial microbiota and suggests microbial dysregulation in endometriosis. Limitations, reasons for caution This is a pilot study with a small sample size, requiring further investigation with a larger cohort. The developed protocol analyzed frozen samples, which may have failed to detect some of the fragile microbial species. Wider implications of the findings The identification of live culturable bacteria through culturomics in endometrial biopsies offers a reliable method for detecting endometritis-associated bacteria. Utilizing culturomics for endometrial microbiota testing shows promise in uncovering specific bacteria associated with gynecological disorders like endometriosis, and it enhances our understanding of potential pathological processes. Trial registration number not applicable

BackgroundWinkia neuii, previously known as Actinomyces neuii, is increasingly recognized as a causative agent of various human infections, while its taxonomy and genomic insights are still understudied.MethodsA Winkia strain NY0527 was isolated from the hip abscess of a patient, and its antibiotic susceptibility was assessed. The genome was hybrid assembled from long-reads and short-reads sequencing. Whole-genome-based analyses on taxa assignment, strain diversity, and pathogenesis were conducted.ResultsThe strain was found to be highly susceptible to beta-lactam antibiotics, but resistant to erythromycin, clindamycin, and amikacin. The complete genome sequences of this strain were assembled and found to consist of a circular chromosome and a circular plasmid. Sequence alignment to the NCBI-nt database revealed that the plasmid had high sequence identity (>90%) to four Corynebacterium plasmids, with 40–50% query sequence coverage. Furthermore, the plasmid was discovered to possibly originate from the sequence recombination events of two Corynebacterium plasmid families. Phylogenomic tree and genomic average nucleotide identity analyses indicated that many Winkia sp. strains were still erroneously assigned as Actinomyces sp. strains, and the documented subspecies within W. neuii should be reclassified as two separate species (i.e., W. neuii and W. anitratus). The core genome of each species carried a chromosome-coded beta-lactamase expression repressor gene, which may account for their broadly observed susceptibility to beta-lactam antibiotics in clinical settings. Additionally, an ermX gene that expresses fluoroquinolone resistance was shared by some W. neuii and W. anitratus strains, possibly acquired by IS6 transposase-directed gene transfer events. In contrast, tetracycline resistance genes were exclusively carried by W. neuii strains. In particular, W. neuii was found to be more pathogenic than W. anitratus by encoding more virulence factors (i.e., 35–38 in W. neuii vs 27–31 in W. anitratus). Moreover, both species encoded two core pathogenic virulence factors, namely hemolysin and sialidase, which may facilitate their infections by expressing poreformation, adhesion, and immunoglobulin deglycosylation activities.ConclusionThis study highlights the underappreciated taxonomic diversity of Winkia spp. and provides populational genomic insights into their antibiotic susceptibility and pathogenesis for the first time, which could be helpful in the clinical diagnosis and treatment of Winkia spp. infections.

Introduction: The aim of this paper is to review and update the information available to date on the influence of diseasemodifying antirheumatic drugs on increased risk of infections after prosthetic surgery or osteosynthesis, and the presentation of a clinical case of infection in a patient operated on for a tibia fracture, that was being treated with Secukinumab. Clinical Case: A 70-year-old patient with psoriatic arthritis treated with Secukinumab and low-dose methotrexate, who suffered a Schatzker type II fracture of the external tibial plateau, operated on by reduction and osteosynthesis with a screwed plate and contribution of cancellous bone tissue. The patient evolved towards deep infection, isolating Actinomyces Neuii. After an early approach with washing and local debridement, the infection was not resolved, so it was necessary to remove the material, clean it, and add Bioglass (Bonalife), given the clinical deterioration of the patient. Antibiotherapy was associated with Linezolid, Clindamycin, with favorable evolution in the resolution of the infection. Discussion and conclusions: Secukinumab is a monoclonal antibody that belongs to the group of drugs known as "interleukin inhibitors", which works by neutralizing the activity of a protein called IL-17A, present in high amounts in diseases such as psoriasis, psoriatic arthritis and axial spondyloarthritis. The current recommendations for the management of rheumatic patients under treatment with biological drugs, who are going to undergo hip or knee prosthetic surgery, is to perform it at the end of the half-life of each drug, but in the case of surgical intervention due to fracture, not there is no recommendation, so extreme precautions must be taken to avoid infection, assessing in each case whether greater antibiotic prophylaxis is necessary.

Vaginal and cervical canal bacteria are associated with women’s health and pregnancy outcomes. Here, we compared their composition and characteristics in 37 reproductive-aged Chinese women including 24 pregnant women with cervical incompetence (vaginal and cervical canal bacteria formed Groups A and B, respectively) and 13 healthy pregnant women (vaginal and cervical canal bacteria formed Groups C and D, respectively) using high-throughput sequencing of the V4 region of 16S rRNA gene. The results of alpha and beta diversity analysis, respectively, indicated no statistical differences between Groups A and B (p = 0.32, 0.06), nor Groups B and D (p = 0.69, 0.74); however, differences were found between Groups C and D (p = 0.02, 0.01) and between Groups A and C (p = 0.04, 0.02). PLS-DA analysis showed that the individuals from each group were irregularly distributed according to their clade. Lactobacillus, Bifidobacterium and Ureaplasma were the dominant genera in all groups. Phylogenetic Investigation of Communities by Reconstruction of Unobserved States (PICRUSts) analysis identified 31 Kyoto Encyclopedia of Genes and Genomes (KEGG) orthologs associated with the bacterial communities from the four groups, including membrane transport, folding, sorting and degradation, xenobiotics biodegradation and metabolism, and nucleotide metabolism. We further determined relationships between pregnancy outcomes (Apgar scores) and certain bacterial species. A significant positive correlation was found between Apgar scores and Actinomyces neuii and Anoxybacillus flavithermus in the vagina and cervical canal of pregnant women with cervical incompetence while Bacteroides plebeius, Bifidobacterium pseudopodium and Staphylococcus petrasii in the cervical canal displayed negative correlations with Apgar scores. Moreover, Clostridium fimetarium, Methanobacterium congolense, Pseudomonas chlororaphis, and Psychrobacter nivimaris in the vagina were negatively correlated with Apgar scores. These bacteria may serve as potential biomarkers, however, additional research is warranted to verify their role in clinical outcomes.

BackgroundActinomycosis is a chronic invasive infection caused by Actinomyces species. Actinomycosis endocarditis has been described, yet considered rare. We present the first reported transcatheter aortic valve implantation (TAVI)-related actinomycosis endocarditis.Case summaryA 70-year-old female patient, presented 4 months after TAVI with malaise and vocal-cord paralysis. She underwent computed tomography angiography which demonstrated a 28 mm pseudoaneurysm of the ascending aorta, which compressed the laryngeal nerves. Her condition rapidly deteriorated with cardiogenic shock and required an emergent surgery, which reviled a tamponade with active bleeding, due to an ascending aortic dissection. She underwent aortic valve and ascending aorta replacement. A 2 cm vegetation was found on the TAVI prosthetic valve and sent for cultures, which later revealed an Actinomyces neuii infection. Long-term intravenous ampicillin treatment was given.DiscussionThis case describes a patient with endocarditis on TAVI prosthetic valve, with an unusual clinical presentation and rapid deterioration to an emergency intervention. This unique presentation of tumour-like tissue invasion is characteristic of actinomycosis, and should be suspected especially following valve replacement.

Better diagnostic value of tissue cultures obtained during mini-open and arthroscopic procedures compared with sterile punctures to identify periprosthetic shoulder infections: a retrospective cohort study.

BackgroundCanine aortic valve endocarditis carries a poor prognosis. In the current literature there are only two reports of infectious endocarditis associated with Actinomyces; Actinomyces turicensis and an Actinomyces-like organism. Endocarditis due to Actinomyces neuii subsp. anitratus (now known as Winkia neuii subsp. anitrata) has rarely been reported in humans, and to the best of our knowledge, has never been reported in dogs.Case presentationA 4 year-3 months old female neutered Great Dane presented with lethargy, hyporexia, ‘praying position’ stance, acute onset of cherry eye and pyrexia. A subtle diastolic heart murmur was detected on thoracic auscultation and echocardiology revealed an irregular lesion adhered to the ventricular aspect of the aortic valve, suggestive of aortic valve endocarditis. Peripheral blood was collected for blood culture. Following 10 days of incubation, blood cultures yielded a growth of aerobic gram-positive filamentous rods which were further biochemically (BioMerieux API Coryne profiling strip) identified as Actinomyces neuii subsp. anitratus. The patient was treated with marbofloxacin and amoxicillin/clavulanic acid for five consecutive months. On repeat echogram, following treatment completion, there was no evidence of aortic valve endocarditis. To the best of our knowledge this is the first case report documenting successful treatment of aortic valve endocarditis caused by Actinomyces neuii subsp. anitratus in a dog.ConclusionsDespite the poor prognosis of canine infectious aortic valve endocarditis, patients with Actinomyces neuii subsp. anitratus infection might have a favourable outcome. It is therefore important identifying the underling infectious cause, as it may have a significant impact on prognosis and treatment outcome when it is caused by Actinomyces neuii subsp. anitratus.

BackgroundEndocarditis caused by Actinomyces species is uncommon with only 30 cases reported in contemporary literature. MethodsWe present a novel case of cardiovascular implantable electronic device (CIED) endocarditis secondary to infection by Actinomyces neuii – a unique non-branching member of the species that grows in both anaerobic and aerobic media.ResultsOur patient, a 51-year-old female, with a history of implantable cardioverter-defibrillator (ICD) placement 17 years prior for heart failure, presented with six weeks of fevers and rigors. She was referred to the infectious disease clinic for evaluation of pyrexia of unknown origin. Her examination was unremarkable, and the ICD pocket was uninflamed. Her initial labs revealed mildly elevated inflammatory markers and renal insufficiency. Blood cultures were positive for slow-growing non-branching gram-positive rods in both aerobic and anaerobic media. These were identified as Actinomyces neuii by mass spectrometry. Review of outside records showed positive blood cultures with Actinomyces neuii at another facility two weeks prior to our evaluation which were not acted upon and thought to be bacterial contamination. The patient was further evaluated with a transesophageal echocardiogram that demonstrated a 3.3 x 2.2cm mobile vegetation attached to the ICD lead. She subsequently underwent removal of her Saint Jude cardiac resynchronization therapy defibrillator and leads using laser and snaring techniques, but the tail end of the ventricular lead fractured and could not be retrieved. The ICD pocket was also found to be infected. A planned 6-week course of IV ampicillin was interrupted by 2 weeks of ceftriaxone for treatment of an intercurrent lower respiratory tract infection. The patient regained her baseline health and was discharged 2 weeks after ICD removal with a LifeVest. She is to complete 12 months of oral amoxicillin therapy after completion of IV antibiotics in view of retained lead fragment, and long standing Actinomyces bacteremia - consistent with published management strategies. Figure 1. Transesophageal echocardiogram demonstrating size of vegetation. Figure 2. Three-dimensional view demonstrating vegetation on the ICD lead.ConclusionHere we describe the first known case of Actinomyces neuii CIED endocarditis with a large lead vegetation and long-standing bacteremia, presenting as pyrexia of unknown origin.Disclosures All Authors: No reported disclosures

The production of Nile tilapia (Oreochromis niloticus) has good technological development; however, today, it is still necessary to make it more efficient. One way to increase efficiency is to prevent disease and improve the food conversion factor. Since previous investigations of tilapia microbiota detected a high proportion of organisms belonging to the order Actinomycetes, this study was to isolate, identify, and describe the species of bacteria microbiota belonging to the cultured Nile tilapia. These were done with Nile tilapia grown in a warm sub-humid climate during spring and summer seasons. The biopsy of different organs was performed for bacteriological culture and 16S rRNA sequencing analysis. From the 180 tissue samples, 49 isolates of the order Actinomycetes were obtained, representing ten species from seven genera: Microbacterium, Brevibacterium, Cellulomonas, Corynebacterium, Kocuria, Actinomyces, and Micrococcus. In spring, Microbacterium dominated, accounting for 74% of the total population. In the summer, lower diversity was observed, with 39% represented by Microbacterium. 16S rRNA sequencing analysis enabled the classification of Actinomyces neuii and Microbacterium lacticum as Kocuria varians and Agromyces indicus; the classification of Microbacterium imperiale as Rhodococcus and Micrococcus luteus was confirmed. No sequences of K. varians have been reported in fish. Microbacterium dextranoliticum showed high similarity to environmental samples. Here is the first study that analyzes the bacteria population in tilapia at the genetic level with an ecosystem approach, present in healthy cultured tilapia, indicating their beneficial associations with the host, making them candidates as probiotics, among other possible functions, applicable in tilapia cultivation.

Actinomycosis remains an underdiagnosed disease, especially in situations such as those specifically caused by Actinomyces neuii, a pathogen that naturally inhabits normal flora but has become implicated as a cause of sepsis and has been observed over a wide age range, and we continue discovering unusual places that can have this pathogen as an infectious origin or as mixed infections.

Actinomyces neuii is an opportunistic pathogen. Within the urogenital tract, it has been associated with bacterial vaginosis and overactive bladder symptoms. Here, we investigate a draft genome sequence of A. neuii UMB1295, which was isolated from a catheterized urine sample from a woman with a urinary tract infection.

<jats:p>Aims: The objectives of this study were to find out whether and to what extent Actinomyces neuii is pathogenic to humans in terms of causing invasive infections and to ascertain the most appropriate and effective antibiotic therapy against this bacterium. Material and method: This study was designed as a systematic review article. MEDLINE, Google Scholar, SCIndex, Cochrane database of published clinical trials - Central and Clinicaltrials.gov databases were systematically searched for primary case reports or case series describing invasive infection with Actinomyces neuii. Results: A literature search identified 23 studies that met the inclusion criteria, describing cases of patients with an invasive infection caused by Actinomyces neuii. It was found that A. neuii could cause endocarditis, endophthalmitis, osteomyelitis, pleural empyema, soft tissue abscesses, neonatal sepsis, ventriculoperitoneal shunt infections and periprosthetic tissue infections. The most prescribed antibiotics for the treatment of Actinomyces neuii infections were amoxicillin and vancomycin (n = 10; 12.3%), followed by penicillin (n =9; 11.1%), gentamicin (n = 6; 7.4%), ampicillin (n = 5; 6.2%) and ceftazidime (n = 4; 4.9%). Antibiotic treatment of infections caused by A. neuii was followed by clinical improvement or complete cure of all patients, with no recorded deaths. Conclusion: A. neuii has a relevant pathogenic potential to cause invasive infections of various organs and tissues, especially in immunocompromised individuals of any age. For the treatment of mild infections caused by this bacterium, the antibiotics of choice are penicillin or amoxicillin, while vancomycin should be used to treat severe infections caused by Actinomyces neuii.</jats:p>

A CASE OF EMPYEMA SECONDARY TO ACTINOMYCES NEUII

BackgroundInfective endocarditis caused by Actinomyces spp. is extremely rare. However, cases by new species of Actinomyces have been increasingly reported due to advances in laboratory techniques, and many of these species do not cause classic presentations of actinomycosis. Actinomyces neuii is reported to have a tendency to cause endovascular infection. The course of infective endocarditis caused by Actinomyces spp. is usually indolent.Case presentationA 61-year-old man with history of infective endocarditis, end stage renal disease, and monoclonal gammopathy was admitted for an abrupt fever, confusion, dysarthria, and facial droop after hemodialysis. Echocardiogram showed vegetations on both the aortic and mitral valves. Two sets of blood culture grew A. neuii. Brain MRI showed multiple bilateral cerebral infarcts consistent with septic emboli. The patient recovered after valvular surgery and prolonged intravenous and oral antibiotic therapy.ConclusionsThis case illustrates an unusually acute presentation of A. neuii infective endocarditis. As with other Gram-positive bacilli, Actinomyces spp. isolates are often regarded as a result of contamination. One should keep it in mind as a cause of infective endocarditis in vulnerable patient populations.

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.

Background: Abdominal Actinomyces infections are rare complications of surgery. A case of Actinomyces neuii presenting as a severe postoperative pelvic infection is described.Case: A 30 year-old nulligravid female was transferred from an outside hospital for a postoperative fluid collection, fever, leukocytosis, and abdominal pain following exploratory laparotomy and bilateral ovarian cystectomy. She rapidly decompensated requiring emergent exploratory laparotomy, bilateral salpingooophorectomy, and abdominal washout. Cultures isolated A. neuii. Following a prolonged ICU admission, she was treated with prolonged antibiotics and made a complete recovery.Conclusions: Rare pathogens, such as A. neuii, may cause severe infections following gynecologic surgery. Multidisciplinary care at tertiary care facilities is critical.

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.

Actinomyces spp. are commensals that may occasionally invade deep tissue structures, causing difficult-to-treat and disfiguring lesions. Information on antimicrobial resistance patterns is limited to observations from two previous studies. Therefore, we examined antimicrobial resistance patterns in clinical isolates of Actinomyces spp. In this retrospective assessment of antimicrobial resistance patterns, we identified 392 Actinomyces spp. at a tertiary care centre from January 2008 to December 2014. MICs of various antimicrobial agents, including ampicillin/sulbactam, meropenem, clindamycin, metronidazole and vancomycin for anaerobic actinomycetes, were obtained by Etest. For aerobic actinomycetes, imipenem, cefotaxime, amikacin, linezolid, moxifloxacin, trimethoprim/sulfamethoxazole and clarithromycin were tested. MIC results were interpreted based on guidelines published by the CLSI (formerly NCCLS). Actinomyces meyeri was predominantly isolated and accounted for 34% of all Actinomyces spp. identified, followed by Actinomyces turicensis with 23%. Actinomyces neuii is considered to be a rare Actinomyces sp., but accounted for 8% of isolates. Antimicrobial susceptibility testing of isolates showed that the Actinomyces spp. were almost uniformly susceptible to β-lactam antimicrobials (with and without β-lactamase inhibitors), carbapenems, tetracyclines and vancomycin. In contrast, Actinomyces spp. isolates were almost uniformly resistant to metronidazole. β-Lactam antimicrobial agents remain the first choice, whereas metronidazole should be avoided, in the treatment of actinomycosis. Reasonable alternatives for treatment are tetracyclines and carbapenems.

Introduction: Actinomyces neuii is a rare cause of peritoneal dialysis-related peritonitis. Case presentation: A 66-year-old male had end-stage renal disease on peritoneal dialysis treatment for 30 months. He developed exit-site leak with infection. Diphtheroids were isolated and considered initially as skin commensals. Dialysis treatment was suspended and on reinstitution he developed peritoneal dialysis-related peritonitis. The organism isolated from the peritoneal dialysis fluid was A. neuii. Conclusion: This case was treated successfully with peritoneal dialysis catheter removal and oral amoxicillin.

The microbial epidemiology of breast implant infections in a regional referral centre for plastic and reconstructive surgery in the south of France