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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 -
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 -
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 -
Infection Apr 2011Actinomyces neuii, a species first described in 1994, has proven to be an exception in this genus on account of its aerobic growth, microscopic morphology (no... (Review)
Review
Actinomyces neuii, a species first described in 1994, has proven to be an exception in this genus on account of its aerobic growth, microscopic morphology (no branching), and the types and location of infections. Abscesses and infected atheromas are the most frequent types of infections, followed by infected skin structures, endophthalmitis, and bacteremias, including endocarditis. They are most likely of endogenous origin. To date, approximately 100 cases have been recorded in the literature. Intra-abdominal and intrathoracic infections, however, have not yet been described, and cases of classical actinomycosis seem to be extremely rare. Prognosis has generally been good with antibiotic and/or surgical treatment. Susceptibility to antibiotics has paralleled that of other Actinomyces spp.
Topics: Abscess; Actinomyces; Actinomycosis; Aerobiosis; Anti-Bacterial Agents; Bacteremia; Debridement; Endocarditis, Bacterial; Endophthalmitis; Humans; Plaque, Atherosclerotic; Skin Diseases, Bacterial
PubMed: 21340579
DOI: 10.1007/s15010-011-0088-6 -
BMC Veterinary Research Feb 2022Canine aortic valve endocarditis carries a poor prognosis. In the current literature there are only two reports of infectious endocarditis associated with Actinomyces;...
BACKGROUND
Canine 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 PRESENTATION
A 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.
CONCLUSIONS
Despite 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.
Topics: Actinomyces; Actinomycosis; Animals; Aorta; Dog Diseases; Dogs; Endocarditis; Endocarditis, Bacterial; Female; Humans
PubMed: 35114997
DOI: 10.1186/s12917-022-03161-3 -
Frontiers in Microbiology 2023, previously known as , is increasingly recognized as a causative agent of various human infections, while its taxonomy and genomic insights are still understudied.
Comparative genomic analyses of the clinically-derived strain NY0527: the reassignment of subsp. and subsp. into two separate species and insights into their virulence characteristics.
BACKGROUND
, previously known as , is increasingly recognized as a causative agent of various human infections, while its taxonomy and genomic insights are still understudied.
METHODS
A 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.
RESULTS
The 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 plasmids, with 40-50% query sequence coverage. Furthermore, the plasmid was discovered to possibly originate from the sequence recombination events of two plasmid families. Phylogenomic tree and genomic average nucleotide identity analyses indicated that many sp. strains were still erroneously assigned as sp. strains, and the documented subspecies within should be reclassified as two separate species (i.e., and ). 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 gene that expresses fluoroquinolone resistance was shared by some and strains, possibly acquired by IS6 transposase-directed gene transfer events. In contrast, tetracycline resistance genes were exclusively carried by strains. In particular, was found to be more pathogenic than by encoding more virulence factors (i.e., 35-38 in vs 27-31 in ). 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.
CONCLUSION
This study highlights the underappreciated taxonomic diversity of 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 spp. infections.
PubMed: 37152761
DOI: 10.3389/fmicb.2023.1147469 -
Frontiers in Microbiology 2022Vaginal and cervical canal bacteria are associated with women's health and pregnancy outcomes. Here, we compared their composition and characteristics in 37...
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 ( = 0.32, 0.06), nor Groups B and D ( = 0.69, 0.74); however, differences were found between Groups C and D ( = 0.02, 0.01) and between Groups A and C ( = 0.04, 0.02). PLS-DA analysis showed that the individuals from each group were irregularly distributed according to their clade. , and 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 and in the vagina and cervical canal of pregnant women with cervical incompetence while , and in the cervical canal displayed negative correlations with Apgar scores. Moreover, , , and 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.
PubMed: 36246259
DOI: 10.3389/fmicb.2022.986326 -
BMC Infectious Diseases Jun 2019Infective endocarditis caused by Actinomyces spp. is extremely rare. However, cases by new species of Actinomyces have been increasingly reported due to advances in...
BACKGROUND
Infective 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 PRESENTATION
A 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.
CONCLUSIONS
This 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.
Topics: Actinomyces; Actinomycosis; Acute Disease; Anti-Bacterial Agents; Echocardiography; Endocarditis; Humans; Male; Middle Aged
PubMed: 31182045
DOI: 10.1186/s12879-019-4149-2 -
Cureus Jul 2023Breast abscesses can be a complication of infectious mastitis or the first presentation of a breast infection, presenting as pain, erythema, and a lump. Actinomycosis is...
Breast abscesses can be a complication of infectious mastitis or the first presentation of a breast infection, presenting as pain, erythema, and a lump. Actinomycosis is a rare chronic disease caused by anaerobic branched filamentous gram-positive bacteria belonging to the genus. It is usually found in the human mouth, digestive tract, and genital tract but can also cause breast abscesses. Actinomycosis affecting the breast is a rare condition that typically occurs as a secondary infection resulting from a pulmonary infection. It is primary when inoculation occurs through the nipple. This report describes the case of a 48-year-old institutionalized female with periareolar swelling in the right breast that had been evolving for approximately two months. The abscess was drained, and the aspirated material contained , a gram-positive bacterium. Actinomycosis of the breast can manifest as either a sinus tract or mass-like features that closely resemble malignancy. The clinical presentation can pose challenges in distinguishing between primary actinomycosis, mastitis, and inflammatory carcinoma. Treatment consists of drainage with needle aspiration or surgical drainage and antibiotic therapy.
PubMed: 37602065
DOI: 10.7759/cureus.42092 -
International Journal of Infectious... Sep 2019Actinomyces infection is a tissue destructive, low-grade infection that often resembles malignancy. We report the case of a 70-year-old male with repeated,...
Actinomyces infection is a tissue destructive, low-grade infection that often resembles malignancy. We report the case of a 70-year-old male with repeated, culture-negative urinary tract infections while intermittently catheterized. At presentation, the patient reported a new episode of urinary tract infection with white discharge in his urine. Transrectal ultrasonography showed two lesions in the prostate, suspect for prostate cancer. However, biopsy did not show cancer, and anaerobic culture grew Actinomyces neuii. A 3-month antibiotic course of amoxicillin eventually cured the infection. This is a case of prostatic soft tissue infection with A. neuii. It is important to consider Actinomyces infection in patients with a non-malignant prostatic mass. Although β-lactam antibiotics do not penetrate the prostate well, the Actinomyces infection was cured by prolonged amoxicillin treatment in this case. It is possible that the tissue damage enhanced the amoxicillin concentration in the infected prostate.
Topics: Actinomyces; Actinomycosis; Aged; Amoxicillin; Anti-Bacterial Agents; Diagnosis, Differential; Humans; Male; Prostate; Prostatic Diseases; Prostatic Neoplasms; Recurrence; Ultrasonography; Urinary Tract Infections
PubMed: 31288092
DOI: 10.1016/j.ijid.2019.06.029