Non-diphtherial Corynebacterial (NDC) species, while previously considered as culture contaminants, are increasingly being implicated in clinical disease and identified as causes of opportunistic infections. In cases where they grow in pure cultures, isolated from a sterile site or repeated isolations from the same patient, NDC may be labeled as clinically significant. We report here a case of non-healing infection of one of the implanted devices in a case of bilateral total hip replacement, caused by multidrug-resistant Corynebacterium striatum. Adherence to infection prevention strategies is essential for the prevention of prosthetic implant infections.

BACKGROUND: Total hip arthroplasty is indubitably a dominant elective surgery in orthopaedics, contributing to prodigious improvement in the quality of life of patients with osteoarthritis. One of the most potentially devastating complications of this operation is periprosthetic joint infection. Immunocompromised patients might be afflicted by infrequent low-virulence organisms not typically detected with conventional procedures. Consequently, employing advanced identification methods, such as the circumstantial sonication of orthopaedic implants, could be crucial to managing such cases.
METHODS: We present a peculiar case of a 72-year-old female patient suffering from a chronic periprosthetic hip infection due to Corynebacterium striatum. The pathogen was only identified after rigorous sonication of the extracted implants. The overall management of this case was immensely exacting, primarily because of the patient\'s impaired immune system, and was finally treated with two-stage revision in our Institution.
METHODS: Although copious literature exists concerning managing periprosthetic hip infections, no concrete guidelines are available for such infections in multimorbid or immunocompromised patients with rare low-virulence microorganisms. Hence, a diagnostic work-up, antibiotic treatment and appropriate revision timeline must be determined. Sonication of extracted implants could be a powerful tool in the diagnostic arsenal, as it can aid in identifying rare microbes, such as Corynebacterium spp. Pertinent antibiotic treatment based on antibiogram analysis and apposite final revision-surgery timing are the pillars for effective therapy of such infections.
CONCLUSIONS: Corynebacterium striatum has been increasingly recognized as an emerging cause of periprosthetic hip infection in the last decade. A conspicuous rise in such reports has been observed in multimorbid or immunocompromised patients after the COVID-19 pandemic. This case is the first report of Corynebacterium striatum periprosthetic hip infection diagnosed solely after the sonication of extracted implants. This paper aims to increase awareness surrounding Corynebacterium spp. prosthetic joint infections, while highlighting the fields for further apposite research.

Corynebacterium striatum, a commensal gram-positive rod, is an emerging cause of human disease in individuals with multiple comorbidities and in immunocompromised patient populations. New microbiologic laboratory tests including molecular diagnostics with greater sensitivity to detect pathogens facilitate appropriate clinical diagnosis and treatment to decrease patient morbidity and mortality. Here we report a case of community-acquired C. striatum infective endocarditis of a native mitral valve in a patient with multiple comorbidities.

Corynebacterium striatum is a type of bacteria normally found in the environment and is considered a benign microbe on the human body surface. However, it can induce severe medical conditions, including bacteremia, infective endocarditis, osteomyelitis, and infections, in other organs. This case study focuses on a 56-year-old male patient with multiple comorbidities who presented with an ischemic stroke. Several days after the insertion of a right internal jugular line, the patient developed fever and tachycardia. Blood cultures revealed the presence of Corynebacterium striatum, a Gram-positive bacilli. Transesophageal echocardiography confirmed the diagnosis of complicated infective endocarditis (IE) with mitral valve vegetation and moderate mitral regurgitation. Prompt treatment with appropriate antibiotics, including linezolid and later vancomycin, led to the patient\'s improvement and eventual discharge in good condition. This case highlights the importance of early recognition, aggressive management, and accurate diagnosis in cases of IE caused by Corynebacterium striatum. Proper antibiotic selection is crucial, considering the emerging antibiotic resistance patterns associated with this pathogen. By addressing these aspects, patient outcomes can be improved, and potential complications such as IE can be prevented.

UNASSIGNED: The aim of this study was to assess the incidence of Corynebacterium striatum prosthetic joint infections (PJI) to determine if an increase has occurred recently. Moreover, susceptibility testing was conducted on C. striatum preserved isolates to determine antibiotic options for these infections.
UNASSIGNED: Retrospective review of PJI cases was conducted from 1/2017 through 1/2021 compared to 1/2021 through 7/2022 to determine how many cases of C. striatum have occurred for each of these time points. From these cases, demographics, outcomes and risk factors for C. striatum PJI were recorded. The preserved clinical isolates from these cases were tested for susceptibility to different antibiotics.
UNASSIGNED: A statistically significant increase in the proportion of C. striatum PJI cases (1.98 to 7.84, p=0.0489) has occurred over the past 16 months at a single institution. Chronic wounds and exposure to daptomycin were associated with the majority of these cases. Susceptibility testing of the clinical isolates showed uniform susceptibility to vancomycin, linezolid and dalbavancin. Uniform resistance was seen with ciprofloxacin, tetracycline and doxycycline as well. Interestingly, 85.7% of the isolates displayed inducible daptomycin resistance after overnight exposure to daptomycin.
UNASSIGNED: C. striatum is an emerging PJI pathogen. It is important for clinicians to be cognizant that this pathogen can have inducible high level daptomycin resistance and that daptomycin is likely not a reliable antibiotic for these infections. While vancomycin and linezolid are the traditional antibiotics to use in these infections, other antibiotics such as dalbavancin, may also have utility, but more research is needed to determine the effectiveness of this antibiotic in C. striatum infections.

Corynebacterium striatum occasionally causes nosocomial infections, such as catheter-related bloodstream infection and pneumonia; however, C. striatum-related infective endocarditis or septic arthritis is uncommon. We present the case of an 85-year-old woman with infective endocarditis at the native valve and septic arthritis at the native shoulder joint caused by C. striatum. The patient was admitted for a 10-day history of fever and right shoulder pain. She had no history of artificial device implantation, injury, arthrocentesis, or hospitalization. A physical examination revealed conjunctival petechiae, a systolic heart murmur, and right shoulder joint swelling. C. striatum was observed in two blood culture sets. Transesophageal echocardiography revealed vegetation in the right aortic coronary cusp. Arthrocentesis at the right shoulder aspirated pyogenic fluid and C. striatum was detected in the culture. The patient was diagnosed with infective endocarditis and septic arthritis caused by C. striatum, and ampicillin was administered based on antimicrobial susceptibility test results. The patient\'s condition was initially stable; however, she developed pulmonary congestion on day 56 and eventually died. An autopsy demonstrated perforation of the aortic left coronary cusp with vegetation. C. striatum may cause native valve endocarditis and native joint septic arthritis.

UNASSIGNED: To investigate Corynebacterium striatum as a nosocomial pathogen infecting hard-to-heal peripheral wounds, such as skin wounds, soft tissue abscesses and osteomyelitis. As of 2023, the medical community were alerted against the risk of emerging systemic and central infections; on the other hand literature on peripheral cutaneous regions is still scarce.
UNASSIGNED: In this study, two groups of patients with similar lesions which were infected were compared: one group with the presence of the coryneform rod, the other without.
UNASSIGNED: In total, Corynebacterium striatum was cultured from 62 patients and 131 samples. Corynebacterium striatum infection correlated well with the presence of: foot ulcer; venous leg ulcer; altered ambulation and/or altered foot loading; peripheral vascular and arterial disease; hospitalisation; malignancy; spinal cord injury; and recent administration of antibiotics (p<0.05 for all associations). Patients with Corynebacterium striatum had a lower overall survival rate compared to patients in the non-Corynebacterium striatum group (28.6 versus 31.6 months, respectively; p=0.0285). Multivariate analysis revealed that Corynebacterium striatum infection was an independent factor for poor prognosis (p<0.0001).
UNASSIGNED: In view of the findings of our study, Corynebacterium striatum appears to be an important opportunistic pathogen infecting peripheral tissues and complicating wound healing. Given its numerous and worrying virulence factors (such as multidrug resistance and biofilm production), particular attention should be given to this pathogen by professional wound care providers in nosocomial and outpatient environments.

Corynebacterium striatum (CS) is an emerging micro-organism in diabetic foot infection for which there are currently few studies. The objective was to analyze the risk factors (RF) related to CS osteomyelitis in patients with diabetic foot.
A case-control study was conducted in the Diabetic Foot Unit between 2015 and 2021. Forty-four patients with osteomyelitis due to CS (cases) and 44 patients with osteomyelitis due a different micro-organism (controls) were included.
Peripheral artery disease (OR: 2.8, p = 0.037), atrial fibrillation (OR: 3.7, p = 0.034), ischemic diabetic foot (OR: 3.3, p = 0.020) and previous prolonged antibiotic therapy more than 14 days (OR: 3.4, p = 0.012) were identified as RF for osteomyelitis due to CS. When performing the multivariate analysis antibiotic therapy >14 days was independent RF (OR: 3.46; p = 0.017).
Previous antibiotic therapy received more than 14 days is an independent and statistically significant RF for CS osteomyelitis in patients with diabetic foot.

Introduction: Genome-scale metabolic models (GEMs) are organism-specific knowledge bases which can be used to unravel pathogenicity or improve production of specific metabolites in biotechnology applications. However, the validity of predictions for bacterial proliferation in in vitro settings is hardly investigated. Methods: The present work combines in silico and in vitro approaches to create and curate strain-specific genome-scale metabolic models of Corynebacterium striatum. Results: We introduce five newly created strain-specific genome-scale metabolic models (GEMs) of high quality, satisfying all contemporary standards and requirements. All these models have been benchmarked using the community standard test suite Metabolic Model Testing (MEMOTE) and were validated by laboratory experiments. For the curation of those models, the software infrastructure refineGEMs was developed to work on these models in parallel and to comply with the quality standards for GEMs. The model predictions were confirmed by experimental data and a new comparison metric based on the doubling time was developed to quantify bacterial growth. Discussion: Future modeling projects can rely on the proposed software, which is independent of specific environmental conditions. The validation approach based on the growth rate calculation is now accessible and closely aligned with biological questions. The curated models are freely available via BioModels and a GitHub repository and can be used. The open-source software refineGEMs is available from https://github.com/draeger-lab/refinegems.

Corynebacterium striatum is considered a rare pathogen in infective endocarditis (IE). C. striatum is a Gram-positive facultative anaerobic bacterium found in the environment and human flora. It is part of the microbiota of the skin and nasal mucosa of humans and has been increasingly reported as the etiologic agent of community-acquired and nosocomial diseases. A 91-year-old female patient was admitted to our clinic with complaints of increased fatigue for a week. Transthoracic echocardiography revealed a labile, echogenic appearance on the mitral valve that may be consistent with infective endocarditis, causing mitral regurgitation. Transesophageal echocardiography (TEE) confirmed this finding on the same day. In three-dimensional (3D) TEE, there was an oval mass of 1.9 cm × 1.1 cm at the level of the P2 scallop of the posterior mitral leaflet, and 1.0 cm of mobile vegetation was observed on it. Three serial blood cultures from peripheral vessels identified C. striatum. Antibiotic treatment of the patient was started with daptomycin 1 × 750 mg and meropenem 3 × 1 g. The cardiology team advised the patient to undergo early surgery, but the patient declined, and the case was followed up medically. On the 10th follow-up day, the patient had a speech disorder. Cerebral computed tomographic angiography showed an appearance compatible with a septic embolism in the left main cerebral artery. The patient\'s condition worsened throughout follow-ups, and she died on day 12. The purpose of presenting this case is to emphasize the importance of Corynebacterium species, which is a cause of rare native valve infectious endocarditis, and to show the difficulties in its treatment.