Aerococcus urinae, a rare cause of infective endocarditis

Emerging pathogens Aerococcus urinae and Aerococcus sanguinicola from a Canadian tertiary care hospital

Background: Aerococcus urinae and Aerococcus sanguinicola are emerging pathogens linked with urinary tract infections. We present a case series of A. urinae and A. sanguinicola isolates characterizing the spectrum of clinical presentation, microbiological characteristics and antimicrobial sensitivities.Methods: Retrospective chart review was performed on patients who grew positive cultures for A. urinae and A. sanguinicola identified on MALDI-TOF in Saskatchewan from January to June 2023. Demographic and clinical variables, antimicrobial susceptibility and prescription were documented.Results: This cohort (n = 115) had a median age 82 years. A. urinae and A. sanguinicola infections spanned from urinary tract infection (n = 96) to urosepsis (n = 6). These infections were predominantly monomicrobial (73.9%) and were susceptible to ceftriaxone, penicillin G and vancomycin. Antimicrobials were seldom prescribed within the urinary tract infection cohort (31.2%).Conclusion: Untreated A. urinae and A. sanguinicola infections can precipitate into urosepsis. The reported antimicrobial susceptibility for these Aerococcus isolates should be utilized to provide appropriate antimicrobial coverage.

Aerococcus urinae: A Rare Cause of Endocarditis Presenting With Acute Stroke

Aerococcus urinae is a rare organism infrequently isolated from cultures. Mostly known to cause urinary tract infection, it can cause bacteremia leading to severe urosepsis and infective endocarditis. Embolization is frequently reported with Aerococcus urinae endocarditis (AUE); hence, the presentation is highly variable. Sequelae such as various central nervous system manifestations, sepsis, valvular regurgitation with heart failure and even coronary artery involvement have been reported. We report a case of a 58-year-old man with AUE of the aortic valve, severe aortic regurgitation and embolic stroke as a result of embolization from AUE and ultimately required aortic valve replacement. Our case highlights this rare cause of endocarditis and offers insight into the variability of patient presentation and risk factors to consider.

Aerococcus urinae - A potent biofilm builder in endocarditis

The diagnosis of infective endocarditis (IE) remains a challenge. One of the rare bacterial species recently associated with biofilms and negative cultures in infective endocarditis is Aerococcus urinae. Whether the low number of reported cases might be due to lack of awareness and misidentification, mainly as streptococci, is currently being discussed. To verify the relevance and biofilm potential of Aerococcus in endocarditis, we used fluorescence in situ hybridization to visualize the microorganisms within the heart valve tissue. We designed and optimized a specific FISH probe (AURI) for in situ visualization and identification of A. urinae in sections of heart valves from two IE patients whose 16S rRNA gene sequencing had deteced A. urinae. Both patients had a history of urinary tract infections. FISH visualized impressive in vivo grown biofilms in IE, thus confirming the potential of A. urinae as a biofilm pathogen. In both cases, FISH/PCR was the only method to unequivocally identify A. urinae as the only causative pathogen for IE. The specific FISH assay for A. urinae is now available for further application in research and diagnostics. A. urinae should be considered in endocarditis patients with a history of urinary tract infections. These findings support the biofilm potential of A. urinae as a virulence factor and are meant to raise the awareness of this pathogen.

Mitral Valve Endocarditis with Perforation from a Urinary Source: An Unusual Case and Literature Review

Aerococcus urinae (AU) is a rare pathogen, identified as gram-positive, catalase-negative coccus that grows in pairs and clusters which has been reported to mainly cause urinary tract infections (UTI), especially in elderly males. Treatment for this microorganism is usually with beta-lactams although cultures with antibiotic susceptibility testing are imperative. We present a case of AU endocarditis initially treated with IV antibiotics; nevertheless, the patient required emergent mitral valve replacement due to severe mitral insufficiency and perforation. We also present an analysis with high-yield points summarizing epidemiology, risk factors, microbiology, clinical features, diagnostic workup, and management of AU in general and AU endocarditis. Finally, we post a literature review of relevant cases and the impact of different variables associated with it.

A rare case of Aerococcus urinae infective endocarditis in an atypically young male: case report and review of the literature

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.

Aerococcus urinae Mitral Valve Endocarditis-Related Stroke: A Case Report and Literature Review

Background. Aerococcus urinae is a rare causative pathogen of infective endocarditis that results in a high risk of embolic events. The mortality rate for A urinae endocarditis is high. Old age and underlying urologic conditions are the best-known risk factors for infection. Case Description. We report the clinical course of the disease in a 49-year-old man who presented symptoms of a urinary tract infection. A few days later, transthoracic echocardiography showed a conspicuous mitral valve with myxomatous alterations. Following the detection of a cerebral embolism with associated stroke symptoms, as well as at the beginning of cardiac failure, the emergency indication for the surgical treatment of mitral valve endocarditis was given. On the second day following the operation, circulatory collapse rapidly developed. Following an unsuccessful attempt at cardiopulmonary resuscitation, the patient died. Review of the Literature. From 1991 to 2017, 29 cases of A urinae–induced endocarditis have been described in PubMed and Medline. One or 2 new cases are published annually. We review all reported cases of A urinae endocarditis, with an emphasis on the predisposing factors, course, and outcomes of the disease. Conclusion. A urinae endocarditis is a rare disease primarily affecting elderly men with urinary tract pathologies and comorbidities. The course of the disease is severe, and the outcome is often fatal. A 16S rDNA polymerase chain reaction investigation of bacterial genome provides proof of the presence of A urinae. Because of the high risk of embolism, rapid treatment should focus on the diseased heart valve. Based on existing data and the experience gained from handling cases, treatment with β-lactam and aminoglycosides is recommended. It is also recommended that operative therapy take place as soon as possible.

A rare case of aerococcus urinae infective endocarditis

Introduction:Aerococcus urinae 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.

Case reports: Aerococcus usually affects males with underlying urinary tract conditions. Herein, we report a case of prosthetic aortic valve endocarditis caused by Aerococcus urinae.

Discussion: Our patient was considered high risk for cardiac surgery and was treated successfully with intravenous antibiotics alone for six weeks.

Conclusion: Infective endocarditis should be considered in all cases of Aerococcus bacteremia and appropriate diagnostic evaluations pursued.

Abbreviations: AV: Aortic valve; IE: Infective endocarditis

A rare case of perineal abscess caused by aerococcus urinae

Aerococcus urinae, a previously misidentified pathogen, has become increasingly recognized to cause severe and even fatal infections. Aerococcus-related perineal abscess infections have not previously been reported in the literature. Most reported cases of infections caused by Aerococcus are urinary tract infections, bacteremia, and even rare cases of endocarditis. We report an unusual case of a perineal abscess caused by Aerococcus urinae.