Molecular Epidemiology of Myroides odoratimimus in Nosocomial Catheter-Related Infection at a General Hospital in China

Molecular characterization of the multi-drug resistant Myroides odoratimimus isolates: a whole genome sequence-based study to confirm carbapenem resistance

The bacteria belonging to the Myroides genus are opportunistic pathogens causing community or hospital-acquired infections that result in treatment failure due to antibiotic resistance. This study aimed to investigate molecular mechanisms of antibiotic resistance, clonal relatedness, and the biofilm forming capacity of the 51 multi-drug resistant Myroides odoratimimus. All isolates were screened for blaKPC, blaOXA, blaVIM, blaIMP, blaMUS, blaTUS, blaNDM, and blaB genes by using PCR amplification. Whole genome sequencing (WGS) was applied on three randomly selected isolates for further investigation of antibiotic resistance mechanisms. Clonal relatedness was analyzed by Pulsed-field gel electrophoresis (PFGE) and the microtiter plate method was used to demonstrate biofilm formation. All isolates were positive for biofilm formation. PCR analysis resulted in a positive for only the blaMUS-1 gene. WGS identified blaMUS-1, erm(F), ere(D), tet(X), and sul2 genes in all strains tested. Moreover, the genomic analyses of three strains revealed that genomes contained a large number of virulence factors (VFs). PFGE yielded a clustering rate of 96%. High clonal relatedness, biofilm formation, and multi-drug resistance properties may lead to the predominance of these opportunistic pathogens in hospital environments and make them cause nosocomial infections.

Myroides odoratimimus: a New Threat with Persistent Infections, Multidrug Resistance, and the Potential for Hospital Outbreaks

Myroides species have recently been reported more frequently in outbreaks in clinics and intensive care units (ICUs). In this study, we aimed to investigate the epidemic potential, antibiotic resistance profile, and risk factors of M. odoratimimus isolates that are increasingly being isolated from the ICUs of our hospital. Data from patients whose Myroides spp. were isolated from their clinical specimens over a 5-year period (September 2016 to January 2022) were retrospectively analyzed. Bacterial identification was performed using a matrix-assisted laser desorption ionization time-of-flight mass spectrometry (MALDI-TOF MS). The presence of antibiotic resistance genes was analyzed using polymerase chain reaction (PCR). Possible clonal associations between isolates were investigated using enterobacterial repetitive intergenic consensus (ERIC)-PCR. As a result, 66 isolates were identified as M. odoratimimus and one isolate was identified as M. odoratus. The blaMUS resistance gene was detected in all M. odoratimimus isolates, whereas sul2 was detected in ten isolates and tetX was detected in 11 isolates. No other resistance genes, such as blaTUS, were detected. Additionally, two different clonal association patterns were discovered in the 24 selected isolates through the ERIC-PCR method. The increase in the immunosuppressive patient population indicate the possibility of encountering this agent and other opportunistic pathogens more frequently in the future.

Cutaneous Infection Associated With Myroides odoratimimus Bacteremia in a Diabetic Patient

In daily medical practice, there exist multidrug resistance bacteria that are not widely recognized. One example of that is the Myroides spp., a Gram-negative bacillus causing skin, urinary, and bloodstream infections, especially in immunocompromised patients. In recent years, multiple cases of difficult hospital management have been reported. Currently, there are no specific guidelines for the prevention and treatment of this infection. This case report presents a patient with type 2 diabetes mellitus with a severe skin infection caused by this microorganism. This is the first case report in Peru of a severe skin infection related to Myroides odoratimimus bacteremia.

A case series and literature review of infections due to Myroides spp.: identification of contributing factors and emerging antibiotic susceptibility trends

Introduction

Infections forby Myroides spp. can lead to significant morbidity and mortality, particularly in immunocompromised patients with underlying co-morbidities. Recent reports have highlighted its intrinsic and acquired drug resistance, making it a particularly challenging infectious agent to combat.

Methods

Myroides spp. isolated and reported in clinically significant urine samples were considered for the study. Identification of the organism was done via the VITEK 2C system. Antibiotic susceptibility testing was done using both manual and automated methods following Clinical and Laboratory Standards Institute (CLSI) guidelines. Existing literature was searched on MEDLINE using PubMed.

Results

We present a series of five catheter-associated urinary tract infections due to Myroides odoratimimus , with sensitivity to only minocycline. This is the first case from Western India, and the third case in the existing literature that shows Myroides sensitivity only to minocycline. Our literature review is the first to systematically describe contributory factors to infection, allowing us to devise a clinically relevant tool that delineates contributory factors and efficacious drugs in Myroides spp. infection.

Conclusion

Myroides spp. infections, previously considered rare and opportunistic, need cognizance and diagnostic suspicion especially in particular associated conditions.

An Increasing Threat in Intensive Care Units, Evaluation of Multi-Drug-Resistant Myroides spp. Infections and Risk Factors

BACKGROUND

Myroides species are gram-negative bacilli that are commonly found in soil and water, acting as low-level opportunistic pathogens and causing a variety of infections.

AIM

The purpose of this study is to assess the risk factors for multidrug-resistant Myroides infections, their association with comorbid illnesses, patient care, and their susceptibility to antibiotics.

METHODS

This retrospective analytical study was conducted in Istanbul Başakşehir Çam and Sakura City Hospital by including patients with Myroides spp isolation in their culture samples. The total hospitalization days, first isolation days, and 30-day mortality values of the patients were analysed statistically, and the significance level was accepted as p < 0.05.

RESULTS

Myroides spp. were isolated from 228 patients' 437 culture samples. Of these cases, 210 (92.1%) were classified as having asymptomatic bacteriuria, and 18 (7.9%) as having an infection caused by Myroides spp. 174 (76.3%) of these patients were followed up in the intensive care unit, and the total hospitalization days (median = 24.50) and the first isolation day (median = 9.50) of infected patients were shorter than colonized patients (p = 0.023, p = 0.030), no difference was found between 30-day mortality (p = 0.312).

CONCLUSIONS

It was observed that Myroides infections could be seen more frequently in patients who were hospitalized for a long time, used broad-spectrum antimicrobials, had invasive procedures, and had co-factors such as diabetes and cerebrovascular disease. In addition, it was observed that the resistance rates of M. odoratus strains were higher than M. odoratimimus strains and the use of quinolone antimicrobials in the treatment of patients with M. odoratimimus infection provided more cure.

Intracranial Myroides odoratimimus Infection After EVD Successfully Treated with Intravenous Plus Intraventricular Tigecycline: A Case Report

Intracranial infections are the most serious and common postoperative complications with significant mortality and morbidity. Myroides odoratimimus (M. odoratimimus), a Gram-negative environmental species and an opportunistic microorganism, predominantly infects immunocompromised individuals. Limited clinical experiences and documented multidrug resistance have resulted in a scarcity of data on the treatment of M. odoratimimus infections. As far as we know, this is the first reported case of an intracranial M. odoratimimus infection with external ventricular drains (EVD) that was effectively treated with a combination of intravenous and intraventricular tigecycline in an immunocompetent adult host.

Extensively Drug-Resistant Myroides odoratus in Critically Ill Patients: A Case Series and Literature Review

The bacterial genus Myroides, like other members of the Flavobacteriaceae family, consists of aerobic, non-motile, Gram-negative bacilli. Myroides spp. is considered predominantly opportunistic pathogens as, historically, most documented infections have been in immunocompromised individuals. Along with advancements in molecular assay testing, there are growing reports of clinically relevant Myroides spp. infections in immunocompetent individuals. These organisms display broad antimicrobial resistance, and while research into their mechanisms of resistance is progressing, genetic testing has revealed metallo-β-lactamases present in their genome. The sporadic identification of Myroides spp. and ongoing clarification of resistance patterns make empiric treatment difficult. This report documents two cases of extensively drug-resistant Myroides odoratus isolated from critically ill but otherwise immunocompetent patients followed by a review of available literature on Myroides spp. antibiotic sensitivities. Our findings indicate that minocycline and moxifloxacin have the highest documented in vitro activity against Myroides spp.

Synergistic efficacy of meropenem, ciprofloxacin and colistin antibiotics against planktonic and biofilm forms of Myroides odoratimimus bacterial isolates

PURPOSE

In this study, it was aimed to investigate the combined synergistic efficacy of colistin (CT), meropenem (MEM), and ciprofloxacin (CIP) antibiotics on planktonic and biofilm forms in Myroidesodoratimimus strains isolated from various clinical specimens.

METHODS

Antibiotic susceptibility was determined by the Kirby-Bauer disk diffusion method. In addition, minimum inhibitory concentrations (MIC) of CIP, MEM, and CT were studied using the standardized broth microdilution method. In vitro synergistic activity of antibiotics against M. odoratimimus planktonic bacteria strains was studied by the Micro Broth Checkerboard method. The microtiter plate (MtP) method was used to determine the effectiveness of antibiotics on M. odoratimimus biofilm formation.

RESULTS

A zone of inhibition was not observed against other antibiotics used except amikacin and linezolid in all strains. While CT/MEM and CT/CIP combinations have a synergistic effect on all strains, the combination CIP/MEM has an additive effect. According to the biofilm inhibition results, all three antibiotics inhibited biofilm formation. However, the efficacy of MEM (60.3-76.5%) and CIP (60.2-77.8%) was approximately two times higher than that of CT (25.4-34.5%). In addition, the effectiveness of combinations of antibiotics on biofilm formation was examined and the percentage of inhibition was 30.8% when CT was used alone, while the biofilm inhibition rates of CT/MEM and CT/CIP were 92.4% and 91.7%, respectively. MEM/CIP combination was inhibited biofilm formation by 75.7%.

CONCLUSIONS

This study is the first report showing the efficacy of CT, MEM and CIP antibiotics, which are frequently used in clinical practice, in combination on M. odoratimimus planktonic and biofilm forms. The findings of our study are particularly guiding for combined antibiotic treatment options in immunosuppressed patients admitted to an intensive care unit (ICU). The CT/MEM combination is currently used frequently. In addition, these results are important in terms of supporting in vitro that CT/CIP and MEM/CIP combinations can also be used as a treatment option in M. odoratimimus related infections.