-
The American Journal of Case Reports Oct 2022BACKGROUND Aerococcus species are a rare cause of endocarditis. Micro-organism identification and antibiotic choice can pose significant management challenges to...
BACKGROUND Aerococcus species are a rare cause of endocarditis. Micro-organism identification and antibiotic choice can pose significant management challenges to clinicians who care for patients with this infection. Aerococcus is a gram-positive micro-organism which is commonly misidentified because it shares many similarities with streptococcus and enterococcus species. Aerococcus urinae is usually found to cause urinary tract infections and occurs more frequently in patients with structural urinary tract abnormalities associated with urethral and ureteral obstruction such as kidney stones, phimosis, and prostate hyperplasia. However, it is reported to rarely cause endocarditis. CASE REPORT A 48-year-old man with a history of cocaine abuse and right hip replacement presented to our emergency department with acute encephalopathy. Through a complicated hospital course, he was found to be septic and the bacteria were initially misidentified as an alpha-hemolytic strep before being correctly identified as Aerococcus urinae. He was found to have multiple cerebral, likely septic, embolic infarcts and aortic valve endocarditis. Identification of the micro-organism on blood cultures was challenging, as were decisions about antibiotic choice. He died despite efforts of a multidisciplinary care team. CONCLUSIONS Our case highlights a unique case of Aerococcus endocarditis and shows the difficulty in initially identifying the bacteria. To our knowledge this is the first case reported in the setting of substance abuse. It also highlights the lack of appropriate guideline-directed therapy with regards to antibiotic choices in this group of patients, emphasizing the importance of further research in this regard.
Topics: Aerococcus; Anti-Bacterial Agents; Aortic Valve; Endocarditis; Endocarditis, Bacterial; Gram-Positive Bacterial Infections; Humans; Male; Middle Aged; Sepsis
PubMed: 36251625
DOI: 10.12659/AJCR.937596 -
International Journal of Medical... Nov 2019Aerococcus urinae is an emerging pathogen that causes urinary tract infections, bacteremia and infective endocarditis. The mechanisms through which A. urinae cause...
Aerococcus urinae is an emerging pathogen that causes urinary tract infections, bacteremia and infective endocarditis. The mechanisms through which A. urinae cause infection are largely unknown. The aims of this study were to describe the surface proteome of A. urinae and to analyse A. urinae genomes in search for genes encoding surface proteins. Two proteins, denoted Aerococcal surface protein (Asp) 1 and 2, were through the use of mass spectrometry based proteomics found to quantitatively dominate the aerococcal surface. The presence of these proteins on the surface was also shown using ELISA with serum from rabbits immunized with the recombinant Asp. These proteins had a signal sequence in the amino-terminal end and a cell wall-sorting region in the carboxy-terminal end, which contained an LPATG-motif, a hydrophobic domain and a positively charged tail. Twenty-three additional A. urinae genomes were sequenced using Illumina HiSeq technology. Six different variants of asp genes were found (denoted asp1-6). All isolates had either one or two of these asp-genes located in a conserved locus, designated Locus encoding Aerococcal Surface Proteins (LASP). The 25 genomes had in median 13 genes encoding LPXTG-proteins (range 6-24). For other Gram-positive bacteria, cell wall-anchored surface proteins with an LPXTG-motif play a key role for virulence. Thus, it will be of great interest to explore the function of the Asp proteins of A. urinae to establish a better understanding of the molecular mechanisms by which A. urinae cause disease.
Topics: Aerococcus; Amino Acid Motifs; Amino Acid Sequence; Animals; Bacterial Proteins; Base Sequence; Cell Wall; Enzyme-Linked Immunosorbent Assay; Genome, Bacterial; Membrane Proteins; Protein Sorting Signals; Proteome; Rabbits; Recombinant Proteins; Virulence
PubMed: 31257068
DOI: 10.1016/j.ijmm.2019.06.005 -
Journal of Community Hospital Internal... Mar 2017is a rare cause of infective endocarditis. Aerococcus is a gram positive cocci that is easily misidentified as Staphylococci or Streptococci. The true incidence rate of...
is a rare cause of infective endocarditis. Aerococcus is a gram positive cocci that is easily misidentified as Staphylococci or Streptococci. The true incidence rate of this pathogen is likely underestimated. Recent advances in laboratory diagnostic methods with matrix-associated laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF-MS) have lead to increased recognition of this pathogen in the clinical microbiology lab, and awareness as a cause of infective endocarditis in the infectious disease community. Aerococcus usually affects males with underlying urinary tract conditions. Herein, we report a case of prosthetic aortic valve endocarditis caused by . Our patient was considered high risk for cardiac surgery and was treated successfully with intravenous antibiotics alone for six weeks. Infective endocarditis should be considered in all cases of bacteremia and appropriate diagnostic evaluations pursued. AV: Aortic valve; IE: Infective endocarditis.
PubMed: 28638578
DOI: 10.1080/20009666.2017.1314072 -
Antibiotics (Basel, Switzerland) May 2024The recognition of the complex (AUC) as an emerging uropathogen has led to growing concerns due to a limited understanding of its disease spectrum and antibiotic...
The recognition of the complex (AUC) as an emerging uropathogen has led to growing concerns due to a limited understanding of its disease spectrum and antibiotic resistance profiles. Here, we investigated the prevalence of macrolide resistance within urinary AUC isolates, shedding light on potential genetic mechanisms. Phenotypic testing revealed a high rate of macrolide resistance: 45%, among a total of 189 urinary AUC isolates. Genomic analysis identified integrative and conjugative elements (ICEs) as carriers of the macrolide resistance gene , suggesting horizontal gene transfer as a mechanism of resistance. Furthermore, comparison with publicly available genomes of related pathogens revealed high ICE sequence homogeneity, highlighting the potential for cross-species dissemination of resistance determinants. Understanding mechanisms of resistance is crucial for developing effective surveillance strategies and improving antibiotic use. Furthermore, the findings underscore the importance of considering the broader ecological context of resistance dissemination, emphasizing the need for community-level surveillance to combat the spread of antibiotic resistance within the urinary microbiome.
PubMed: 38786161
DOI: 10.3390/antibiotics13050433 -
The Journal of Infection Apr 2018Aerococcus urinae and Aerococcus sanguinicola cause urinary tract infections (UTIs) and antibiotic treatment recommendations are solely based on in vitro findings and... (Observational Study)
Observational Study
OBJECTIVES
Aerococcus urinae and Aerococcus sanguinicola cause urinary tract infections (UTIs) and antibiotic treatment recommendations are solely based on in vitro findings and limited clinical experience. Our objective was to investigate the effectiveness of different treatment strategies in aerococcal UTI through a prospective observational study.
METHODS
Urine samples with aerococci were identified and patients were enrolled. The aerococci were subjected to Etests. Information on clinical symptoms, and the treatment given, was collected. Patients were interviewed after the conclusion of treatment to assess clinical cure and a control urine culture assessed the microbiological cure.
RESULTS
Of 31,629 urine samples, 144 grew aerococci and fulfilled the inclusion criteria. 91 patients gave consent and the 72 patients with UTI were assessed for treatment outcome. 53 patients had A. urinae UTI, while 19 had A. sanguinicola UTI. Nitrofurantoin was most commonly prescribed, achieving clinical and microbiological success in 71/76% of cases of A. urinae UTI, and 42/50% of cases of A. sanguinicola UTI. Pivmecillinam achieved success in patients with A. urinae cystitis and ciprofloxacin in patients with pyelonephritis.
CONCLUSIONS
Our results support that nitrofurantoin is a valid option for the treatment of cystitis caused by A. urinae.
Topics: Aerococcus; Aged; Aged, 80 and over; Anti-Bacterial Agents; Cystitis; Disk Diffusion Antimicrobial Tests; Female; Gram-Positive Bacterial Infections; Humans; Male; Microbial Sensitivity Tests; Middle Aged; Nitrofurantoin; Prospective Studies; Sweden; Treatment Outcome; Urinary Tract Infections
PubMed: 29253561
DOI: 10.1016/j.jinf.2017.12.009 -
Microbial Pathogenesis Nov 2017Aerococcus sanguinicola and Aerococcus urinae are emerging pathogens in clinical settings mostly being causative agents of urinary tract infections (UTIs), urogenic...
Genomic characterization, phylogenetic analysis, and identification of virulence factors in Aerococcus sanguinicola and Aerococcus urinae strains isolated from infection episodes.
Aerococcus sanguinicola and Aerococcus urinae are emerging pathogens in clinical settings mostly being causative agents of urinary tract infections (UTIs), urogenic sepsis and more seldomly complicated infective endocarditis (IE). Limited knowledge exists concerning the pathogenicity of these two species. Eight clinical A. sanguinicola (isolated from 2009 to 2015) and 40 clinical A. urinae (isolated from 1984 to 2015) strains from episodes of UTIs, bacteremia, and IE were whole-genome sequenced (WGS) to analyze genomic diversity and characterization of virulence genes involved in the bacterial pathogenicity. A. sanguinicola genome sizes were 2.06-2.12 Mb with 47.4-47.6% GC-contents, and 1783-1905 genes were predicted whereof 1170 were core-genes. In case of A. urinae strains, the genome sizes were 1.93-2.44 Mb with 41.6-42.6% GC-contents, and 1708-2256 genes of which 907 were core-genes. Marked differences were observed within A. urinae strains with respect to the average genome sizes, number and sequence identity of core-genes, proteome conservations, phylogenetic analysis, and putative capsular polysaccharide (CPS) loci sequences. Strains of A. sanguinicola showed high degree of homology. Phylogenetic analyses showed the 40 A. urinae strains formed two clusters according to two time periods: 1984-2004 strains and 2010-2015 strains. Genes that were homologs to virulence genes associated with bacterial adhesion and antiphagocytosis were identified by aligning A. sanguinicola and A. urinae pan- and core-genes against Virulence Factors of Bacterial Pathogens (VFDB). Bacterial adherence associated gene homologs were present in genomes of A. sanguinicola (htpB, fbpA, lmb, and ilpA) and A. urinae (htpB, lap, lmb, fbp54, and ilpA). Fifteen and 11-16 CPS gene homologs were identified in genomes of A. sanguinicola and A. urinae strains, respectively. Analysis of these genes identified one type of putative CPS locus within all A. sanguinicola strains. In A. urinae genomes, five different CPS loci types were identified with variations in CPS locus sizes, genetic content, and structural organization. In conclusion, this is the first study dealing with WGS and comparative genomics of clinical A. sanguinicola and A. urinae strains from episodes of UTIs, bacteremia, and IE. Gene homologs associated with antiphagocytosis and bacterial adherence were identified and genetic variability was observed within A. urinae genomes. These findings contribute with important knowledge and basis for future molecular and experimental pathogenicity study of UTIs, bacteremia, and IE causing A. sanguinicola and A. urinae strains.
Topics: Adolescent; Adult; Aerococcus; Aged; Aged, 80 and over; Bacteremia; Bacterial Adhesion; Bacterial Capsules; Base Composition; Base Sequence; Chaperonin 60; Child; DNA, Bacterial; Denmark; Endocarditis, Bacterial; Female; Genes, Bacterial; Genome Size; Genomics; Gram-Positive Bacterial Infections; Humans; Male; Middle Aged; Phylogeny; Polysaccharides; Proteome; RNA, Ribosomal, 16S; Sepsis; Sequence Analysis; Urinary Tract Infections; Virulence Factors; Young Adult
PubMed: 28943151
DOI: 10.1016/j.micpath.2017.09.042 -
Biochemistry Insights 2019() and () are gram-positive bacteria belonging to the family Aerococcaceae and colonize the human immunocompromised and catheterized urinary tract. We identified both...
() and () are gram-positive bacteria belonging to the family Aerococcaceae and colonize the human immunocompromised and catheterized urinary tract. We identified both pathogens in polymicrobial urethral catheter biofilms (CBs) with a combination of 16S rDNA sequencing, proteomic analyses, and microbial cultures. Longitudinal sampling of biofilms from serially replaced catheters revealed that each species persisted in the urinary tract of a patient in cohabitation with 1 or more gram-negative uropathogens. The and proteomes revealed active glycolytic, heterolactic fermentation, and peptide catabolic energy metabolism pathways in an anaerobic milieu. A few phosphotransferase system (PTS)-based sugar uptake and oligopeptide ABC transport systems were highly expressed, indicating adaptations to the supply of nutrients in urine and from exfoliating squamous epithelial and urothelial cells. Differences in the vs metabolisms pertained to citrate lyase and utilization and storage of glycogen (evident only in proteomes) and to the enzyme Xfp that degrades d-xylulose-5'-phosphate and the biosynthetic pathways for 2 protein cofactors, pyridoxal 6'-phosphate and 4'-phosphopantothenate (expressed only in proteomes). A predicted ZnuA-like transition metal ion uptake system was identified for while expressed 2 LPXTG-anchored surface proteins, one of which had a predicted pilin D adhesion motif. While these proteins may contribute to fitness and virulence in the human host, it cannot be ruled out that and fill a niche in polymicrobial biofilms without being the direct cause of injury in urothelial tissues.
PubMed: 31555049
DOI: 10.1177/1178626419875089 -
International Journal of Antimicrobial... Sep 2016Aerococcus urinae can cause severe infections (bacteraemia and endocarditis) that are associated with high mortality. However, data on the bactericidal and synergistic...
Aerococcus urinae can cause severe infections (bacteraemia and endocarditis) that are associated with high mortality. However, data on the bactericidal and synergistic activity for clinically implemented antibiotics are scarce. Time-kill analyses were performed on two clinical isolates (AU1 and AU2) and the reference strain ATCC 700306 for penicillin (PG), ceftriaxone (CRO), gentamicin (GEN), daptomycin (DAP) and their combinations. AU1 and AU2 were CRO-resistant (MICs, 2 µg/mL) and ATCC 700306 was high-level GEN-resistant (MIC, 512 µg/mL), whereas all strains were PG- and DAP-susceptible (MICs, ≤0.125 and ≤1 µg/mL, respectively). CFU counts were determined at various time points from 0 to 48 h. All experiments were performed at 0.5×, 1×, 2× and 4× MIC. PG and CRO were not bactericidal for all strains, whereas DAP exhibited bactericidal activity at all concentrations for AU2 and ATCC 700306. The combination of PG or CRO with GEN was bactericidal for AU1 and AU2 at antibiotic concentrations ≥1× MIC. Bactericidal synergism was detected for PG or CRO combined with GEN in the two clinical isolates. PG plus CRO showed non-bactericidal synergism for ATCC 700306. DAP with GEN was synergistic at 1× MIC for AU1, whereas the killing activity of DAP was too pronounced to detect potential synergism in AU2. The combination of PG or CRO with GEN is synergistic and bactericidal. Moreover, these in vitro data suggest that DAP may represent a potential bactericidal treatment alternative against A. urinae. This finding could be important for the treatment of patients with a β-lactam allergy or renal insufficiency.
Topics: Aerococcus; Aged; Aged, 80 and over; Anti-Bacterial Agents; Colony Count, Microbial; Daptomycin; Drug Synergism; Female; Gentamicins; Gram-Positive Bacterial Infections; Humans; Microbial Sensitivity Tests; Microbial Viability; Time Factors; beta-Lactams
PubMed: 27451085
DOI: 10.1016/j.ijantimicag.2016.05.007 -
Journal of Microscopy and Ultrastructure 2021is a Gram-positive, catalase- and oxidase-negative, microaerophilic, nonmotile bacteria species rarely associated with human infections such as arthritis, bacteremia,...
INTRODUCTION
is a Gram-positive, catalase- and oxidase-negative, microaerophilic, nonmotile bacteria species rarely associated with human infections such as arthritis, bacteremia, endocarditis, and meningitis. The bacteria are also often confused with streptococci species or treated as a contaminant.
PATIENTS AND METHODOLOGY
We conducted a retrospective, observational cohort study on all patients with isolates in blood samples from July 2010 to June 2019. All categorical data were presented as counts and proportions, whereas continuous data were presented as median and interquartile ranges.
RESULTS
A total of 20 isolates were identified over the study period of 9 years. Of these, was isolated in 10 (50%), in 6 (30%), and (not speciated) in 4 (20%). The median age was 74.3 years (12 males and 8 females). The two most frequent presentations were fever (15 of 20) and altered mentation (6 of 15). Most of the patients (11 of 15) had at least one predisposing comorbidity related to the urinary tract system (8 with recurrent urinary tract infection, 7 with urinary incontinence, 3 with an indwelling catheter, 2 with renal stones, and 1 each with benign prostatic hyperplasia and a recent cystoscopy). The median white blood cell count was 18,426 cells/mL, median hemoglobin 10.96 g/dL, median platelet count 191,000 cells/μL, median blood urea nitrogen 28.6 mg/dL, and median creatinine 1.54 mg/dL. The urinary tract was the most likely source of bacteremia (10 of 20) based on either imaging findings (5 cases), positive urine culture for (4 cases), or instrumentation history (1 case). In the rest, the cause of bacteremia could not be found. Endocarditis was suspected in 9 out of 20 patients. Transthoracic echocardiography/transesophageal echocardiography (TEE) confirmed 3 cases (2 aortic valves, 1 mitral valve and pacemaker). Interestingly, one case had septic emboli causing a right frontal stroke with a normal TEE and normal Doppler study for deep venous thrombosis. Blood cultures were positive in 35% (7 of 20) with polymicrobial growth, 3 with coagulase-negative staphylococci, 2 with , and the other 2 each with and Of the 20 cases, 9 and 10 required intensive care unit level care and vasopressor support, respectively. Most of the patients were treated for 5-14 days except the 3 cases with infective endocarditis (IE). The median hospital stay duration was 6.55 days with 2 fatalities (2 out of 20 patients).
CONCLUSION
Old age and underlying urologic conditions are the best-known risk factors for infection. Recent advances in diagnostic technology have led to an increase in detection of -related infections. The rare occurrence of in human infections and resultant lack of randomized control trials have resulted in a significant degree of clinical uncertainty in the management of IE.
PubMed: 33850708
DOI: 10.4103/JMAU.JMAU_61_19 -
BMC Infectious Diseases Oct 2018Aerococcus urinae is a gram-positive, alpha-hemolytic coccus bacterium primarily implicated in less than 1 % of all symptomatic urinary tract infections. Risk factors... (Review)
Review
BACKGROUND
Aerococcus urinae is a gram-positive, alpha-hemolytic coccus bacterium primarily implicated in less than 1 % of all symptomatic urinary tract infections. Risk factors for disease include male gender, advanced age, and comorbid genitourinary tract pathology. Infections beyond the genitourinary tract are rare, though spondylodiscitis, perineal abscesses, lymphadenitis, bacteremia, meningitis, and endocarditis have been reported. Less than fifty cases of A. urinae infective endocarditis (IE) have been described in the literature. The rare occurrence of A. urinae in human infections and resultant lack of randomized controlled trials have resulted in a significant degree of clinical uncertainty in the management of A. urinae IE.
CASE PRESENTATION
We present an unusual case of a forty-three year-old male with A. urinae infective endocarditis (IE) who was successfully treated with mitral valve replacement and six weeks of penicillin/gentamicin therapy. In addition, we include a comprehensive review of all reported cases of IE due to A. urinae with specific attention to therapeutic regimens and treatment durations.
CONCLUSION
Recent advances in diagnostic technology have led to an increase in the frequency A. urinae is diagnosed. Reviewing cases of Aerococcus urinae infections, their clinical courses and subsequent management can assist future healthcare providers and their patients.
Topics: Adult; Aerococcus; Anti-Bacterial Agents; Comorbidity; Endocarditis, Bacterial; Gram-Positive Bacterial Infections; Humans; Male; Mitral Valve; Survival Analysis
PubMed: 30333008
DOI: 10.1186/s12879-018-3414-0