Global prevalence and distribution of antibiotic resistance among clinical isolates of Stenotrophomonas maltophilia: A systematic review and meta-analysis

Stenotrophomonas maltophilia bacteremia in adult patients with hematological diseases: clinical characteristics and risk factors for 28-day mortality

Patients with hematological diseases are at high risk for Stenotrophomonas maltophilia (SM) bacteremia. This study retrospectively analyzed the clinical characteristics and risk factors for 28-day mortality among 140 adult hematological patients diagnosed with SM bacteremia from January 2012 to July 2023. he overall 28-day mortality was 31.43% (44/140), with a median age of 44 years. The median hospital stay before SM bacteremia onset was 25 days, and 69.29% of patients had unresolved neutropenia. All patients had received broad-spectrum antibiotics in the past month, and 69.29% developed breakthrough bacteremia during carbapenem therapy. Independent risk factors for mortality included a Sequential Organ Failure Assessment (SOFA) score ≥5, tigecycline exposure, age ≥60, and pulmonary infection. Patients with ≥2 risk factors were stratified into the high-risk group, with a significantly higher 28-day mortality compared with the low-risk group (56.52% vs 7.04%, P < 0.001). Treatment with trimethoprim-sulfamethoxazole (TMP/SMX) (P = 0.008) or TMP/SMX combined with cefoperazone/sulbactam (CSL) (P = 0.005) was associated with survival benefits among high-risk patients. Overall, SM bacteremia usually occurs in hematological patients with prolonged hospitalization, unresolved neutropenia, and extensive use of broad-spectrum antibiotics, especially carbapenems. Patients with high SOFA scores, advanced age, pulmonary infection, or recent tigecycline exposure are at higher risk of mortality. The preferred treatment is TMP/SMX rather than fluoroquinolones, with combination therapy of TMP/SMX and CSL considered a feasible treatment option.IMPORTANCEThis study, representing the largest cohort of adult hematological patients with SM bacteremia to date, strengthens the validity of existing findings and provides new insights into its clinical management. We identify risk factors for 28-day mortality, revealing that patients with two or more risk factors experience particularly high mortality rates. This highlights the importance of early identification and targeted management of high-risk individuals. Our findings also demonstrate that TMP/SMX is superior to fluoroquinolones and suggest that combining TMP/SMX with CSL may offer additional survival benefits.

Effective strategies for managing trimethoprim-sulfamethoxazole and levofloxacin-resistant Stenotrophomonas maltophilia infections: bridging the gap between scientific evidence and clinical practice

PURPOSE OF REVIEW

To discuss the therapeutic options available for the management of difficult-to-treat strains of Stenotrophomonas maltophilia ( Sma ), namely those resistant to trimethoprim-sulfamethoxazole and fluoroquinolones.

RECENT FINDINGS

Recent pharmacological studies have highlighted the fact that current breakpoints for first-line antibiotics against Sma are too high. In light of these data, it is likely that the prevalence of difficult-to-treat (DTR) Sma is underestimated worldwide. Two promising alternatives for treating DTR strains are cefiderocol and the combination of aztreonam and an L2 inhibitor. However, clinical trials are currently very limited for these antibiotics and no comparative studies have been carried out to date. It is important to note that the clinical efficacy of cefiderocol appears to be inferior to that initially anticipated from in-vitro and animal studies. Consequently, minocycline and ceftazidime may remain viable options if they are used against strains with a low minimum inhibitory concentration. We advise against the use of intravenous polymyxins and tigecycline. Finally, recent literature does not support the systematic use of combination therapy or long-course treatments. In the coming years, phage therapy may become a promising approach against DTR Sma infections.

SUMMARY

Overall, clinical comparative studies focused on DTR strains are required in order to provide more accurate and actionable information for therapeutic decisions.

Antibiotic Resistance and Virulence Factors in Clinical Isolates of Stenotrophomonas maltophilia from Hospitalized Patients in Tehran, Iran

Stenotrophomonas maltophilia causes challenging infections in immunocompromised patients, exhibiting increasing resistance to multiple antimicrobials and possessing various virulence genes, including emerging resistance to trimethoprim-sulfamethoxazole. A total of 80 clinical isolates of S. maltophilia were collected from multiple hospitals in Tehran, Iran. This study conducted an analysis of antibiotic susceptibility by disc diffusion method and E-test assay, resistance and virulence gene frequencies were examined by PCR-sequencing, and multilocus sequencing typing (MLST) was performed for strain typing. Across the tested isolates, we observed notably high resistance rates for imipenem 80 (100%), meropenem 78(97.5%), and ceftazidime 72 (90%), while trimethoprim-sulfamethoxazole (SXT) showed a lower resistance rate of 2 (2.5%). Minocycline and levofloxacin demonstrated the highest susceptibility rates, with 70 (87.5%) and 80 (100%), respectively. The prevalence of antibiotic resistance genes bla L1, and bla L2 was 71 (88.75%) and 76 (95%), respectively. Additionally, the PCR analysis revealed that the frequency of virulence genes (fliC, virB, papD, pilU, hlyIII, stmPr1, and stmPr2) was 78 (97.5%), 77 (96.25%), 58 (72.5%), 77 (96.2%), 76 (95%), 31 (38.75%), and 80 (100%), respectively. Resistance to SXT isolate belong to the sequence type (ST15) and exhibits allelic profiles of (10, 29, 21, 21, 32, 32, and 10). The data obtained from our investigation have indicated that SXT remains an efficacious antibiotic and also highlighted the importance of effective management, identification of resistant isolates, and typing methods to address the global prevalence of antibiotic resistance in S. maltophilia.

Innovative strategies against superbugs: Developing an AI-CDSS for precise Stenotrophomonas maltophilia treatment

OBJECTIVES

The World Health Organization named Stenotrophomonas maltophilia (SM) a critical multi-drug resistant threat, necessitating rapid diagnostic strategies. Traditional culturing methods require up to 96 h, including 72 h for bacterial growth, identification with matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) through protein profile analysis, and 24 h for antibiotic susceptibility testing. In this study, we aimed at developing an artificial intelligence-clinical decision support system (AI-CDSS) by integrating MALDI-TOF MS and machine learning to quickly identify levofloxacin and trimethoprim/sulfamethoxazole resistance in SM, optimizing treatment decisions.

METHODS

We selected 8,662 SM from 165,299 MALDI-TOF MS-analysed bacterial specimens, collected from a major medical centre and four secondary hospitals. We exported mass-to-charge values and intensity spectral profiles from MALDI-TOF MS .mzML files to predict antibiotic susceptibility testing results, obtained with the VITEK-2 system using machine learning algorithms. We optimized the models with GridSearchCV and 5-fold cross-validation.

RESULTS

We identified distinct spectral differences between resistant and susceptible SM strains, demonstrating crucial resistance features. The machine learning models, including random forest, light-gradient boosting machine, and XGBoost, exhibited high accuracy. We established an AI-CDSS to offer healthcare professionals swift, data-driven advice on antibiotic use.

CONCLUSIONS

MALDI-TOF MS and machine learning integration into an AI-CDSS significantly improved rapid SM resistance detection. This system reduced the identification time of resistant strains from 24 h to minutes after MALDI-TOF MS identification, providing timely and data-driven guidance. Combining MALDI-TOF MS with machine learning could enhance clinical decision-making and improve SM infection treatment outcomes.

Clinical characteristics and genome epidemiology of Stenotrophomonas maltophilia in Japan

BACKGROUND

Stenotrophomonas maltophilia is a carbapenem-resistant Gram-negative pathogen increasingly responsible for difficult-to-treat nosocomial infections.

OBJECTIVES

To describe the contemporary clinical characteristics and genome epidemiology of patients colonized or infected by S. maltophilia in a multicentre, prospective cohort.

METHODS

All patients with a clinical culture growing S. maltophilia were enrolled at six tertiary hospitals across Japan between April 2019 and March 2022. The clinical characteristics, outcomes, antimicrobial susceptibility and genomic epidemiology of cases with S. maltophilia were investigated.

RESULTS

In total, 78 patients were included representing 34 infection and 44 colonization cases. The median age was 72.5 years (IQR, 61-78), and males accounted for 53 cases (68%). The most common comorbidity was localized solid malignancy (39%). Nearly half of the patients (44%) were immunosuppressed, with antineoplastic chemotherapy accounting for 31%. The respiratory tract was the most common site of colonization (86%), whereas bacteraemia accounted for most infection cases (56%). The 30 day all-cause mortality rate was 21%, which was significantly higher in infection cases than colonization cases (35% versus 9%; adjusted HR, 3.81; 95% CI, 1.22-11.96). Susceptibility rates to ceftazidime, levofloxacin, minocycline and sulfamethoxazole/trimethoprim were 14%, 65%, 87% and 100%, respectively. The percentage of infection ranged from 13% in the unclassified group to 86% in genomic group 6A. The percentage of non-susceptibility to ceftazidime ranged from 33% in genomic group C to 100% in genomic groups 6 and 7 and genomic group geniculate.

CONCLUSIONS

In this contemporary multicentre cohort, S. maltophilia primarily colonized the respiratory tract, whereas patients with bacteraemia had the highest the mortality from this pathogen. Sulfamethoxazole/trimethoprim remained consistently active, but susceptibility to levofloxacin was relatively low. The proportions of cases representing infection and susceptibility to ceftazidime differed significantly based on genomic groups.

Stenotrophomonas maltophilia outbreak in a university hospital: epidemiological investigation and literature review of an emerging healthcare-associated infection

Stenotrophomonas maltophilia was considered to be a low-virulence organism. But it has emerged as a prominent opportunistic pathogen in patients with certain risk factors. This study aimed to describe an outbreak experienced in our hospital with all dynamics while evaluating previous S. maltophilia outbreak reports. S. maltophilia isolates were obtained from a university hospital in Türkiye in a seven-months period. Antimicrobial resistance, type of infections, predisposing factors of infected patients, antibiotic therapy, outcome of infections, and outbreak source were investigated. Also, S. maltophilia outbreaks in the literature were reviewed. In the 12 months prior to the outbreak, prevalence rate of clinical samples including S. maltophilia was 7/1,000 patient per day, opposed to 113/1,000 patient per day during the outbreak. Although a large number of cases were observed in a short seven-month period, a source of contamination could not be detected. Stable mortality rates (or remaining close to the average) during outbreaks can be attributed to the careful attention paid by laboratory and clinic physicians during procedures. S. maltophilia has potential to spread outbreaks and infect patients in operating rooms and intensive care units during invasive procedures.

Temporal analysis of prevalence and antibiotic-resistance patterns in Stenotrophomonas maltophilia clinical isolates in a 19-year retrospective study

Stenotrophomonas maltophilia is a nonfermenting gram-negative bacterium associated with multiple nosocomial outbreaks. Antibiotic resistance increases healthcare costs, disease severity, and mortality. Multidrug-resistant infections (such as S. maltophilia infection) are difficult to treat with conventional antimicrobials. This study aimed to investigate the isolation rates, and resistance trends of S. maltophilia infections over the past 19 years, and provide future projections until 2030. In total, 4466 patients with S. maltophilia infection were identified. The adult and main surgical intensive care unit (ICU) had the highest numbers of patients (32.2%), followed by the cardiology department (29.8%), and the paediatric ICU (10%). The prevalence of S. maltophilia isolation increased from 7% [95% confidence interval (CI) 6.3-7.7%] in 2004-2007 to 15% [95% CI 10.7-19.9%] in 2020-2022. Most S. maltophilia isolates were resistant to ceftazidime (72.5%), levofloxacin (56%), and trimethoprim-sulfamethoxazole (14.05%), according to our study. A consistent and significant difference was found between S. maltophilia-positive ICU patients and non-ICU patients (P = 0.0017) during the three-year pandemic of COVID-19 (2019-2021). The prevalence of S. maltophilia isolates is expected to reach 15.08% [95% CI 12.58-17.59%] by 2030. Swift global action is needed to address this growing issue; healthcare authorities must set priorities and monitor infection escalations and treatment shortages.

Stenotrophomonas maltophilia: The Landscape in Critically Ill Patients and Optimising Management Approaches

The aim of this review is to synthesise the key aspects of the epidemiology, current microbiological diagnostic challenges, antibiotic resistance rates, optimal antimicrobial management, and most effective prevention strategies for Stenotrophomonas maltophilia (SM) in the intensive care unit (ICU) population. In recent years, resistance surveillance data indicate that SM accounts for less than 3% of all healthcare-associated infection strains, a percentage that doubles in the case of ventilator-associated pneumonia (VAP). Interestingly, SM ranks as the third most isolated non-glucose fermenter Gram-negative bacilli (NFGNB). Although this NFGNB genus has usually been considered a bystander and colonising strain, recently published data warn about its potential role as a causative pathogen of severe infections, particularly pneumonia and bloodstream infections (BSI), not only for the classical immunocompromised susceptible host patients but also for critically ill ones even without overt immunosuppression. Indeed, it has been associated with crude 28-day mortality as high as 54.8%, despite initial response following targeted therapy. Additionally, alongside its intrinsic resistance to a wide range of common antimicrobials, various worldwide and local surveillance studies raise concerns about an increase in ICU settings regarding resistance to first-line drugs such as cotrimoxazole or tigecycline. This scenario alerts ICU physicians to the need to reconsider the best stewardship approach when SM is isolated in obtained samples from critically ill patients. Despite the coverage of this multidrug-resistant bacterium (MDRB) provided by some traditional and a non-negligible number of current pipeline antimicrobials, an ecological and cost-effective strategy is needed in the present era.

Global mapping of antibiotic resistance rates among clinical isolates of Stenotrophomonas maltophilia: a systematic review and meta-analysis

INTRODUCTION

Infections caused by Stenotrophomonas maltophilia are clinically important due to its intrinsic resistance to a broad range of antibiotics. Therefore, selecting the most appropriate antibiotic to treat S. maltophilia infection is a major challenge.

AIM

The current meta-analysis aimed to investigate the global prevalence of antibiotic resistance among S. maltophilia isolates to the develop more effective therapeutic strategies.

METHOD

A systematic literature search was performed using the appropriate search syntax after searching Pubmed, Embase, Web of Science and Scopus databases (May 2023). Statistical analysis was performed using Pooled and the random effects model in R and the metafor package. A total of 11,438 articles were retrieved. After a thorough evaluation, 289 studies were finally eligible for inclusion in this systematic review and meta-analysis.

RESULT

Present analysis indicated that the highest incidences of resistance were associated with doripenem (97%), cefoxitin (96%), imipenem and cefuroxime (95%), ampicillin (94%), ceftriaxone (92%), aztreonam (91%) and meropenem (90%) which resistance to Carbapenems is intrinsic. The lowest resistance rates were documented for minocycline (3%), cefiderocol (4%). The global resistance rate to TMP-SMX remained constant in two periods before and after 2010 (14.4% vs. 14.6%). A significant increase in resistance to tigecycline and ceftolozane/tazobactam was observed before and after 2010.

CONCLUSIONS

Minocycline and cefiderocol can be considered the preferred treatment options due to low resistance rates, although regional differences in resistance rates to other antibiotics should be considered. The low global prevalence of resistance to TMP-SMX as a first-line treatment for S. maltophilia suggests that it remains an effective treatment option.

Isolation, characterization, and genomic analysis of BUCT627: a lytic bacteriophage targeting Stenotrophomonas maltophilia

Stenotrophomonas infections pose significant therapeutic challenges due to escalating resistance to antibiotics and chemotherapeutic agents. Phages offer a potential solution by virtue of their specific bacterial targeting capabilities. In this study, we isolated a new Stenotrophomonas bacteriophage, named BUCT627, from hospital sewage. Phage BUCT627 exhibited a 30-min latent period and demonstrated a burst size of 46 plaque forming unit (PFU)/cell. Remarkably, this phage displayed robust stability across a wide pH range (pH 3-13) and exhibited resilience under varying thermal conditions. The receptor of phage BUCT627 on Stenotrophomonas maltophilia No. 826 predominantly consist of surface proteins. The complete genome of phage BUCT627 is a 61 860-bp linear double-stranded DNA molecule with a GC content of 56.3%, and contained 99 open reading frames and two tRNAs. Notably, no antibiotic resistance, toxin, virulence-related genes, or lysogen-formation gene clusters was identified in BUCT627. Transmission electron microscopy and phylogeny analysis indicated that this phage was a new member within the Siphoviridae family. The results of this study will enhance our understanding of phage diversity and hold promise for the development of alternative therapeutic strategies against S. maltophilia infections.

Responses of microbial interactions and functional genes to sulfamethoxazole in anammox consortia

Sulfamethoxazole (SMX) has been widely detected in various environments and its potential environmental risks have caused great concerns. However, the impact mechanism of SMX on microbial interactions among anammox consortia remain unknown. A long-term exposure experiments (140 d) was carried out to systematically examine the influence of SMX (0-1000 μg/L) on the anammox system, especially microbial network dynamics and variations of key metabolic genes. Results showed that anammox system could adapt to SMX below 500 μg/L and maintain a high nitrogen removal efficiency (NRE) of 85.35 ± 2.42%, while 1000 μg/L SMX significantly decreased the abundance of functional microbes and deteriorated denitrification performance with NRE dropped to 36.92 ± 15.01%. Co-occurrence network analysis indicated that 1000 μg/L SMX decreased the interactions between Proteobacteria and Chloroflexi and limited AnAOB from playing an important role as central nodes in the subnetwork of Planctomycetes. Metagenomics analysis found that genes associated with nitrogen removal (i.e., hdh, hzs, nirS, and hao) showed lower expression level after addition of SMX, while SMX-related ARGs (sul1 and sul2) increased by 1.22 and 2.68 times. This study provided us a relatively comprehensive perspective in response of microbial interactions and metabolic activity to various SMX concentrations.

Current viewpoint on the epidemiology of nonfermenting Gram-negative bacterial strains

PURPOSE OF REVIEW

This article aims to review the epidemiology of nonfermenting Gram-negative bacilli (NFGNB) based on recent literature reports, particularly, of the less common, but with emerging clinical significance species.

RECENT FINDINGS

The reported frequency of multidrug-resistant Acinetobacter baumannii and Pseudomonas aeruginosa is increasing, with very significant variability, however, between different countries. Apart from the major NFGNB, that is, A. baumannii and P. aeruginosa, already recognized as of critical importance healthcare risks, several other NFGNB genera have been increasingly associated with diverse severe infections, such as Stenotrophomonas maltophilia, Burkholderia spp., Elizabethkingia spp., Chryseobacterium spp., Achromobacter spp., Alcaligenes spp., Sphingomonas spp., Shewanella spp. and Ralstonia spp., among others.

SUMMARY

The exploration of the epidemiology, as well as the pathogenic potential of the of the less frequent, but emerging and increasingly reported NFGNB, is crucial, not only for immunocompromised patients, but also for critically ill patients without overt immunosuppression. As we are heading fast towards a postantibiotic era, such information would contribute to the optimal antimicrobial management, that is, providing prompt, appropriate antimicrobial coverage when needed and, at the same time, avoiding overuse and/or inappropriate use of antimicrobial therapy. Also, it would help to better understand their transmission dynamics and to develop effective prevention strategies.

Comparative genomics analysis of Stenotrophomonas maltophilia strains from a community

Background

Stenotrophomonas maltophilia is a multidrug-resistant (MDR) opportunistic pathogen with high resistance to most clinically used antimicrobials. The dissemination of MDR S. maltophilia and difficult treatment of its infection in clinical settings are global issues.

Methods

To provide more genetic information on S. maltophilia and find a better treatment strategy, we isolated five S. maltophilia, SMYN41-SMYN45, from a Chinese community that were subjected to antibiotic susceptibility testing, biofilm formation assay, and whole-genome sequencing. Whole-genome sequences were compared with other thirty-seven S. maltophilia sequences.

Results

The five S. maltophilia strains had similar antibiotic resistance profiles and were resistant to β-lactams, aminoglycosides, and macrolides. They showed similar antimicrobial resistance (AMR) genes, including various efflux pumps, β-lactamase resistance genes (blaL1/2), aminoglycoside resistance genes [aac(6'), aph(3'/6)], and macrolide-resistant gene (MacB). Genome sequencing analysis revealed that SMYN41-SMYN45 belonged to sequence type 925 (ST925), ST926, ST926, ST31, and ST928, respectively, and three new STs were identified (ST925, ST926, and ST928).

Conclusion

This study provides genetic information by comparing genome sequences of several S. maltophilia isolates from a community of various origins, with the aim of optimizing empirical antibiotic medication and contributing to worldwide efforts to tackle antibiotic resistance.

Stenotrophomonas maltophilia: An Urgent Threat with Increasing Antibiotic Resistance

Stenotrophomonas maltophilia is a Gram-negative opportunistic pathogen that can cause many infections, such as chronic pulmonary infections in patients with cystic fibrosis and infections in immunocompromised patients with hematology-oncology diseases. Because of its remarkable and increasing antimicrobial resistance, the treatment of S. maltophilia infections is quite challenging. Meanwhile, the prevalence of S. maltophilia infections is increasing in recent decades. S. maltophilia is usually considered to be of low virulence but has numerous virulence factors involved in the pathogenesis of infections caused by S. maltophilia. By revealing its pathogenesis associated with virulence factors and molecular mechanisms of antimicrobial resistance, many existing or potential therapeutic strategies have been developed. However, because of the limited treatment options, new strategies are urgently needed. Here, we review the recent progresses in research on S. maltophilia which may help to develop more effective treatments against this increasing threat.

Diversity of blaL1-like genes in Stenotrophomonas species: insights from genome analysis of publicly available genome sequences

L1 metallo-β-lactamases produced by Stenotrophomonas maltophilia exhibit high diversity. Here, we characterized the genomes of Stenotrophomonas species harboring blaL1-like genes using publicly available genome sequences. Our findings provide evidence that Stenotrophomonas species with blaL1-like genes constitute a complex comprising many species with high genetic diversity, and similarities between blaL1-like genes are lower than those of the genome. This suggests that the diversity of blaL1-like is attributable to species diversity in Stenotrophomonas species harboring blaL1-like and the rapid evolutionary changes in blaL1-like genes.

The Relationship between the Biofilm Genes and Antibiotic Resistance in Stenotrophomonas maltophilia

Objectives

Today, Stenotrophomonas maltophilia (S. maltophilia) is a major opportunistic pathogen among hospitalized or immunocompromised patients. Antibiotic-resistant clinical isolates are increasing in several parts of the world. Various antibiotic-resistance and biofilm-forming genes are identified in this bacterium. Its capacity to form biofilms is an important virulence factor that may impact antibiotic-resistance patterns. In the current study, we evaluated the biofilm-formation capacity, antibiotic-resistance profile, and prevalence of biofilm-forming genes as well as antibiotic resistance genes among S. maltophilia isolates.

Materials and Methods

In this cross-sectional study, 94 clinical S. maltophilia isolates were recovered from four tertiary-care hospitals in Iran between 2021 and 2022. The presence of the selected antibiotic-resistance genes and biofilm-forming genes was examined by polymerase chain reaction (PCR). The ability of biofilm formation was examined by microtiter plate assay. The Kirby-Bauer disc diffusion method was used to evaluate the trimethoprim-sulfamethoxazole (TMP-SMX), levofloxacin, and minocycline resistance.

Results

S. maltophilia is mainly isolated from bloodstream infections. Notably, 98.93% of isolates were biofilm producers, of which 19.35%, 60.22%, and 20.43% produced strong, moderate, and weak biofilm, respectively. The frequency of biofilm genes was 100%, 97.88%, 96.80%, and 75.53% for spgM, rmlA, smf-1, and rpfF, respectively. Isolates with the genotype of smf-1+/rmlA+/spgM+/rpfF+ were mostly strong biofilm producers. Among the antibiotic-resistance genes, the Smqnr, L1, and sul1 had the highest prevalence (76.59%, 72.34%, and 64.89), respectively. Antimicrobial susceptibility evaluation showed 1.06%, 3.19%, and 6.3% resistance to minocycline, TMP-SMX, and levofloxacin.

Conclusion

The results of the current study demonstrated that S. maltophilia isolates differ in biofilm-forming ability. Moreover, smf-1, rmlA, and spgM genes were presented in all strong biofilm producers. Although the overall resistance rate to the evaluated antibiotics was high, there was no statistically significant relation between antibiotic resistance and the type of biofilm.

Stenotrophomonas in diversified cropping systems: friend or foe?

In the current scenario, the use of synthetic fertilizers is at its peak, which is an expensive affair, possesses harmful effects to the environment, negatively affecting soil fertility and beneficial soil microfauna as well as human health. Because of this, the demand for natural, chemical-free, and organic foods is increasing day by day. Therefore, in the present circumstances use of biofertilizers for plant growth-promotion and microbe-based biopesticides against biotic stresses are alternative options to reduce the risk of both synthetic fertilizers and pesticides. The plant growth promoting rhizobacteria (PGPR) and microbial biocontrol agents are ecologically safe and effective. Owning their beneficial properties on plant systems without harming the ecosystem, they are catching the widespread interest of researchers, agriculturists, and industrialists. In this context, the genus Stenotrophomonas is an emerging potential source of both biofertilizer and biopesticide. This genus is particularly known for producing osmoprotective substances which play a key role in cellular functions, i.e., DNA replication, DNA-protein interactions, and cellular metabolism to regulate the osmotic balance, and also acts as effective stabilizers of enzymes. Moreover, few species of this genus are disease causing agents in humans that is why; it has become an emerging field of research in the present scenario. In the past, many studies were conducted on exploring the different applications of Stenotrophomonas in various fields, however, further researches are required to explore the various functions of Stenotrophomonas in plant growth promotion and management of pests and diseases under diverse growth conditions and to demonstrate its interaction with plant and soil systems. The present review discusses various plant growth and biocontrol attributes of the genus Stenotrophomonas in various food crops along with knowledge gaps. Additionally, the potential risks and challenges associated with the use of Stenotrophomonas in agriculture systems have also been discussed along with a call for further research in this area.

The prevalence of colistin resistance in clinical Stenotrophomonas maltophilia isolates worldwide: a systematic review and meta-analysis

While trimethoprim-sulfamethoxazole (TMP-SMX) is the first-line therapy of Stenotrophomonas maltophilia infections, colistin is one of the therapeutic options in cases of allergy or resistance to TMP-SMX. However, understanding the global status of resistance to colistin amongst S. maltophilia isolates could be helpful for appropriate antibiotic prescription. This study aimed to conduct a systematic review and meta-analysis to examine the prevalence of colistin resistance in clinical S. maltophilia isolates worldwide. According to eligibility criteria, a total of 61 studies were included in the analysis. The pooled prevalence for colistin resistance was 42% (95% CI: 35-49%), ranging from 0.1 to 97%. Subgroups analysis indicated that, the pooled prevalence of colistin resistance was 44% (95% CI: 29-60%) in 15 studies during 2000-2010, and it was estimated to be 41% (95% CI: 33-50%) in 46 articles from 2011 to 2021. It was 46% (95% CI: 35-58%) in the studies that used broth microdilution method, and 39% (95% CI: 30-49%) in the studies with other used methods. The resistance rate in Asian countries was 45% (95% CI: 31-60%), in European countries was 45% (95% CI: 34-56%) and in the countries of North and South America was 33% (95% CI: 20-46%). Our review showed notable resistance to colistin in clinical S. maltophilia isolates. Given the estimated resistance rates, alternative antibiotics could be preferred to treat serious infections due to S. maltophilia.