Chronic postoperative endophthalmitis caused by Actinomyces neuii

Antimicrobial treatment of Acinetobacter neuii invasive infections: A systematic review

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.

Actinomyces neuii: a case report of a rare cause of acute infective endocarditis and literature review

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.

Actinomycosis, a lurking threat: a report of 11 cases and literature review

Actinomycosis remains characteristically uncommon, but is still an important cause of morbidity. Its clinical presentation is usually indolent and chronic as slow growing masses that can evolve into fistulae, and for that reason are frequently underdiagnosed. Actinomyces spp is often disregarded clinically and is classified as a colonizing microorganism. In this review of literature, we concomitantly present 11 cases of actinomycosis with different localizations, diagnosed at a tertiary hospital between 2009 and 2016. We outline the findings of at least one factor of immunosuppression in > 90% of the reported cases.

ACTINOMYCES NEUII ENDOPHTHALMITIS AFTER INTRAVITREAL ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR INJECTION

PURPOSE

To describe a case of acute endophthalmitis caused by Actinomyces neuii after intravitreal anti-vascular endothelial growth factor injection.

METHODS

Observational case report, review of published literature.

RESULTS

A 67-year-old white man with wet age-related macular degeneration developed endophthalmitis secondary to A. neuii on the 10th day after intravitreal anti-vascular endothelial growth factor injection. Both anterior chamber and vitreous cultures were positive for A. neuii. He was treated successfully with intravitreal injection of vancomycin and ceftazidime.

CONCLUSION

This is the first published report of culture-positive endophthalmitis caused by A. neuii after intravitreal injection.

Infections Caused by Actinomyces neuii: A Case Series and Review of an Unusual Bacterium

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 neuii Isolated From a 20-Month-Old Girl With Cervical Lymphadenitis

Actinomycetes are Gram-positive bacteria that can be part of the normal human flora of the gastrointestinal, pulmonary, and genital tract. Infections are rare, slowly progressing and most commonly affect the cervicofacial region. Actinomyces israelii is the most frequently isolated species but a number of other species may cause infection. We report the first postnatally acquired case of an actinomycosis caused by A. neuii in a child. We also provide a systematic review of all published cases of A. neuii infections. In children, there is one case report of a premature infant with perinatally acquired A. neuii sepsis. In adults 21 cases have currently been reported and A. neuii infection was associated with endophthalmitis after eye surgery, foreign material-associated infection and abscess formation in the inguinal, axillary, and mammary area. Our case highlights that a A. neuii infection is also a potential differential diagnosis in children with chronic lymphadenitis.

Actinomyces and related organisms in human infections

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.

Actinomyces endogenous endophthalmitis in a cat following multiple dental extractions

An 8-year-old, brachycephalic, mixed breed cat underwent full mouth tooth extractions for the treatment of tooth root abscessation. Subsequently, the cat developed anterior uveitis refractory to topical therapy that eventually necessitated enucleation. Actinomyces species were isolated from both the tooth root abscesses and the anterior chamber after enucleation. Histopathology of the enucleated eye revealed panophthalmitis with abundant intralesional bacteria morphologically consistent with Actinomyces. Between the time of tooth root extraction and enucleation (20 weeks), the cat was diagnosed with hyperthyroidism and treated with oral steroids for inflammatory bowel syndrome. We believe this report represents a rare case of endogenous endophthalmitis secondary to dental disease, possibly precipitated by concurrent immunosuppression.

Actinomyces neuii: review of an unusual infectious agent

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.

Prosthetic valve endocarditis due to Actinomyces neuii successfully treated with antibiotic therapy

Endocarditis due to Actinomyces neuii is a rare disease, with only 14 reported cases. Recently, A. neuii was added to the list of species implicated in endocarditis of native valves. We now report the first case of prosthetic valve endocarditis and the first successful control of endocarditis caused by this organism without surgical intervention.

Incidence, clinical features, causative organisms, and visual outcomes of delayed-onset pseudophakic endophthalmitis

PURPOSE

To report the incidence, clinical features, causative organisms, and visual outcomes associated with delayed-onset pseudophakic endophthalmitis.

METHODS

We retrospectively reviewed the clinical records and microbiology files of all patients with culture-proven endophthalmitis that was present 6 weeks or more after cataract extraction and posterior chamber intraocular lens (IOL) implantation who were treated at King Khaled Eye Specialist Hospital (KKESH) during a 10-year period.

RESULTS

From January 1997 through December 2006, 17 patients with culture-proven, delayed-onset pseudophakic endophthalmitis were treated at KKESH. Of the 17 cases, only 5 cases developed delayed-onset endophthalmitis, among 29,509 cataract surgeries performed at KKESH, indicating an incidence rate of 0.017% (5/29,509). The mean time between cataract surgery and diagnosis of endophthalmitis was 5+/-2.48 months. The culture isolates revealed Propionibacterium acnes in 7 (41.2%) eyes, polymicrobial (mixed) infections in 3 (17.6%) eyes, Staphylococcus species in 3 (17.6 %) eyes, fungal infections in 3 (17.6%) eyes, and Alcaligenes xylosoxidans in 1 (5.9%) eye. The mean follow-up period was 29.8 months. The final visual outcomes were as follows: 7 eyes (41.2%) achieved a final best-corrected visual acuity of >or=20/60; 6 eyes (35.3%) achieved a best-corrected visual acuity of <20/60 to >or= count fingers; 2 eyes (11.8%) had hand motion to light perception vision; and 2 eyes (11.8%) were enucleated.

CONCLUSIONS

In this study, infection by P acnes was the most common cause of delayed-onset pseudophakic endophthalmitis and had the most favorable visual outcome, whereas fungal endophthalmitis had the worst visual prognosis.

Ventriculoperitoneal shunt infection caused by Actinomyces neuii subsp. neuii

Actinomyces neuii subsp. neuii is a rare isolate in clinical specimens. The organism was previously designated CDC coryneform group 1 and was renamed in 1994. A case of a ventriculoperitoneal shunt infection caused by this organism is described.

Actinomyces--gathering evidence of human colonization and infection

The roles of the 'classical'Actinomyces spp. as colonizers of oral cavities of man and animals, in development of intra-oral infections and as agents of actinomycosis have been well documented. This mini-review focuses on perceptions of human colonization and infection that have emerged in the past decade, largely as a result of advances in classification, identification and direct detection from clinical material. Arguably, of the greatest importance is the recognition of actinomycosis as a major factor and indicator of poor prognosis in both infected osteoradionecrosis and bisphosphonate-associated osteonecrosis of the jaws. Among recently described species, Actinomyces graevenitzii has been isolated almost exclusively from oral and respiratory sites and may be a causative agent of actinomycosis. Conversely, several other Actinomyces spp. are isolated commonly from superficial soft tissue infections. Members of the genus Actinobaculum, which is closely related to Actinomyces, are strongly associated with urosepsis. Isolation and identification of Actinomyces and related genera by conventional methods remain difficult. Diagnosis is commonly belated and based solely upon histological findings. Development of direct detection methods may aid patient management and further elucidate clinical associations.

Actinomyces neuii subspecies anitratus chronic endophthalmitis after cataract surgery

PURPOSE

To report a case of unusual chronic endophthalmitis by Actinomyces neuii subspecies anitratus.

METHODS

A 75-year-old man underwent uneventful phacoemulsification with implantation of a foldable posterior chamber intraocular lens in his right eye. Four weeks after surgery, a chronic post-operative endophthalmitis characterized by anterior chamber and vitreous cellular debris developed in this eye. Cultures were positive, and A neuii subspecies anitratus was identified by polymerase chain reaction and subsequent rRNA sequence analysis. Immediate treatment included intravitreal and intensive topical antibiotics along with oral ciprofloxacin.

RESULTS

The condition improved rapidly, and 6 months after surgery the patient was asymptomatic, the best spectacle-corrected visual acuity was 20/22, and the anterior chamber was quiet.

CONCLUSIONS

A neuii subspecies anitratus should be considered in the differential diagnosis of chronic endophthalmitis after cataract surgery. Polymerase chain reaction and subsequent RNA typing were useful in detecting the causative organism, and intravitreal antibiotics were successful.