Search

Achromobacter xylosoxidans is an emerging pathogen that causes airway infections in patients with cystic fibrosis. Knowledge of virulence factors and protein secretion systems in this bacterium is limited. Twin arginine translocation (Tat) is a protein secretion system that transports folded proteins across the inner cell membranes of gram-negative bacteria. Tat has been shown to be important for virulence and cellular processes in many different bacterial species. This study aimed to investigate the role of Tat in iron metabolism and host cell adhesion in A. xylosoxidans. Putative Tat substrates in A. xylosoxidans were identified using the TatFind, TatP, and PRED-Tat prediction tools. An isogenic tatC deletion mutant (ΔtatC) was generated and phenotypically characterized. The wild-type and ΔtatC A. xylosoxidans were fractionated into cytosolic, membrane, and periplasmic fractions, and the expressed proteome of the different fractions was analysed using liquid chromatography-mass spectrometry (LC-MS/MS). A total of 128 putative Tat substrates were identified in the A. xylosoxidans proteome. The ΔtatC mutant showed attenuated host cell adhesion, growth rate, and iron acquisition. Twenty predicted Tat substrates were identified as expressed proteins in the periplasmic compartment, nine of which were associated with the wild type. The data indicate that Tat secretion is important for iron acquisition and host cell adhesion in A. xylosoxidans.

Aim and background: Achromobacter xylosoxidans is a rare opportunistic pathogen that can cause severe infections, particularly in immunocompromised patients. This case report describes a patient with A. xylosoxidans septicemia complicated by severe symptomatic bradycardia, hyperkalemia, and acute kidney injury (AKI) requiring dialysis. Case description: A 78-year-old female, a known case of hypertension, diabetes, and ischemic heart disease, presented with altered mental status and hypotension. She was found to have A. xylosoxidans septicemia, severe hyperkalemia, and symptomatic bradycardia requiring temporary pacing. Despite antibiotic treatment and management of electrolyte imbalances, the patient developed AKI requiring hemodialysis. Coronary angiography revealed critical triple-vessel disease, and the patient underwent successful coronary artery bypass grafting (CABG) surgery. Conclusion: This case highlights the potentially severe complications associated with A. xylosoxidans infections, including cardiac and renal dysfunction. Prompt recognition and aggressive management of these complications are crucial for patient survival. Clinical significance: This case emphasizes the importance of considering A. xylosoxidans as a potential cause of severe sepsis, especially in immunocompromised patients. Early diagnosis and appropriate antimicrobial therapy, along with management of associated complications such as cardiac and renal dysfunction, are essential for improving patient outcomes. [ABSTRACT FROM AUTHOR]

Abstract Background Marginal zone lymphomas of mucosa-associated lymphatic tissues (MZL of MALT) are a group of indolent B-cell neoplasms, which are thought to arise from chronic antigenic stimulation of B-cells either due to underlying chronic infection or autoimmune disease. Little is known about potential causative pathogens in pulmonary MZL (PMZL), although some data suggests a potential role of Achromobacter (A.) xylosoxidans. Methods An index case of chronic pulmonary colonisation with Tropheryma (T.) whipplei and subsequent development of PMZL was identified by T. whipplei specific PCR and metagenomic next genome sequencing (mNGS). This case prompted a retrospectively conducted analysis of T. whipplei-specific PCRs in lung tissue from PMZL patients (n = 22), other pulmonary lymphomas, and normal controls. Positive results were confirmed by mNGS. A systematic search for T. whipplei and A. xylosoxidans in our in-house mNGS dataset comprising autopsy lungs, lung biopsies and lung resection specimens (n = 181) was subsequently performed. Results A 69-year-old patient presented with weight loss and persistent pulmonary consolidation. Subsequent mNGS analysis detected T. whipplei in the resected lung specimen. An antibiotic regimen eventually eliminated the bacterium. However, the consolidation persisted, and the diagnosis of PMZL was made in a second lung resection specimen. A second case of T. whipplei-associated PMZL was subsequently detected in the retrospectively analysed PMZL cohort. Both cases showed comparatively few mutations and no mutations in genes encoding for NF-κB pathway components, suggesting that T. whipplei infection may substitute for mutations in these PMZL. None of the samples in our in-house dataset tested positive for T. whipplei. In contrast, A. xylosoxidans was frequently found in both autopsy lungs and lung biopsy / resection specimens that were not affected by PMZL (> 50%). Conclusions Our data suggests that T. whipplei colonisation of lungs may trigger PMZL as a potential driver. Systematic analyses with larger cohorts should be conducted to further support this hypothesis. The frequent detection of A. xylosoxidans in lung tissue suggests that it is a common component of the pulmonary microbiome and therefore less likely to trigger lymphomas.

Background: Marginal zone lymphomas of mucosa-associated lymphatic tissues (MZL of MALT) are a group of indolent B-cell neoplasms, which are thought to arise from chronic antigenic stimulation of B-cells either due to underlying chronic infection or autoimmune disease. Little is known about potential causative pathogens in pulmonary MZL (PMZL), although some data suggests a potential role of Achromobacter (A.) xylosoxidans. Methods: An index case of chronic pulmonary colonisation with Tropheryma (T.) whipplei and subsequent development of PMZL was identified by T. whipplei specific PCR and metagenomic next genome sequencing (mNGS). This case prompted a retrospectively conducted analysis of T. whipplei-specific PCRs in lung tissue from PMZL patients (n = 22), other pulmonary lymphomas, and normal controls. Positive results were confirmed by mNGS. A systematic search for T. whipplei and A. xylosoxidans in our in-house mNGS dataset comprising autopsy lungs, lung biopsies and lung resection specimens (n = 181) was subsequently performed. Results: A 69-year-old patient presented with weight loss and persistent pulmonary consolidation. Subsequent mNGS analysis detected T. whipplei in the resected lung specimen. An antibiotic regimen eventually eliminated the bacterium. However, the consolidation persisted, and the diagnosis of PMZL was made in a second lung resection specimen. A second case of T. whipplei-associated PMZL was subsequently detected in the retrospectively analysed PMZL cohort. Both cases showed comparatively few mutations and no mutations in genes encoding for NF-κB pathway components, suggesting that T. whipplei infection may substitute for mutations in these PMZL. None of the samples in our in-house dataset tested positive for T. whipplei. In contrast, A. xylosoxidans was frequently found in both autopsy lungs and lung biopsy / resection specimens that were not affected by PMZL (> 50%). Conclusions: Our data suggests that T. whipplei colonisation of lungs may trigger PMZL as a potential driver. Systematic analyses with larger cohorts should be conducted to further support this hypothesis. The frequent detection of A. xylosoxidans in lung tissue suggests that it is a common component of the pulmonary microbiome and therefore less likely to trigger lymphomas. [ABSTRACT FROM AUTHOR]

Biodegradation was considered a promising and environmentally friendly method for treating environmental pollution caused by diuron. However, the mechanisms of biodegradation of diuron required further research. In this study, the degradation process of diuron by Achromobacter xylosoxidans SL-6 was systematically investigated. The results suggested that the antioxidant system of strain SL-6 was activated by adding diuron, thereby alleviating their oxidative stress response. In addition, degradation product analysis showed that diuron in strain SL-6 was mainly degraded by urea bridge cleavage, dehalogenation, deamination, and ring opening, and finally cis, cis-muconic acid was generated. The combined analysis of metabolomics and transcriptomics revealed the biodegradation and adaptation mechanism of strain SL-6 to diuron. Metabolomics analysis showed that after the strain SL-6 was exposed to diuron, metabolic pathways such as tricarboxylic acid cycle (cis, cis-muconic acid), glutathione metabolism (oxidized glutathione), and urea cycle (arginine) were reprogrammed in the cells. Furthermore, diuron could induce the production of membrane transport proteins in strain SL-6 cells and overexpress antioxidant enzyme genes, finally ultimately promoting the up-regulation of genes encoding amide hydrolases and dioxygenases, which was revealed by transcriptomics studies. This work enriched the biodegradation mechanism of phenylurea herbicides and provided guidance for the removal of diuron residues in the environment and promoting agriculture sustainable development [ABSTRACT FROM AUTHOR]

An 11-year-old male neutered American bulldog was presented for evaluation of thrombocytopenia, acute onset of ataxia, and vomiting. A new murmur was auscultated on physical examination. Transthoracic echocardiographic examination revealed a bicuspid aortic valve, vegetative lesions on the aortic valve, and continuous shunting from the aortic root to the left atrium through an aorta to left atrial fistula. The dog was euthanized due to its guarded prognosis and critical condition. Pathological examination confirmed presence of a bicuspid aortic valve, aorto-left atrial fistula, and aortic infective endocarditis. Antemortem blood culture revealed two unusual organisms: Achromobacter xylosoxidans and Fusobacterium mortiferum. [ABSTRACT FROM AUTHOR]

Textile effluents containing toxic dyes must be treated effectively before discharge to prevent adverse environmental impacts. Traditional physical and chemical treatment methods are costly and generate secondary pollutants. In contrast, biological treatment is a more suitable, clean, versatile, eco-friendly, and cost-effective technique for treating textile effluent. It is well established that indigenous microbial populations present in effluents can effectively degrade toxic dyes. In this regard, Achromobacter xylosoxidans DDB6 was isolated from the effluent sample to decolorize crystal violet (CV), Coomassie brilliant blue (CBB), and alizarin red (AR) by 67.20%, 28.58%, and 20.41%, respectively. The growth parameters of A. xylosoxidans DDB6 in media supplemented with 100 ppm of various dyes were determined using the modified Gompertz growth model. The immobilized cells in calcium alginate beads showed apparent decolorization rate constant of 0.27, 0.18, and 0.13 h−1 for CV, CBB, and AR, respectively. The immobilized cells in a packed bed reactor with an optimum flow rate of 0.5 mL/min were used to treat 100 ppm of CV with a percentage decolorization of 79.47% after three cycles. Based on the findings, A. xylosoxidans DDB6 could be effectively used for decolorization of various dyes. [ABSTRACT FROM AUTHOR]

Purpose: Achromobacter xylosoxidans is an emerging pathogen mainly associated with resistant nosocomial infections. This bacteria had been isolated in the ear together with other pathogens in cultures from patients with chronic otitis media, but it had never been reported as a cause of osteomyelitis of the external auditory canal. Case presentation: We present a unique case of a healthy 81-year-old woman who presented with left chronic otorrhea refractory to topical and oral antibiotic treatment. Otomicroscopy revealed an erythematous and exudative external auditory canal (EAC) with scant otorrhea. The tympanic membrane was intact, but an area of bone remodeling with a small cavity anterior and inferior to the bony tympanic frame was observed. Otic culture isolated multi-drug-resistant A. xylosoxidans, only sensitive to meropenem and cotrimoxazole. Temporal bone computed tomography showed an excavation of the floor of the EAC compatible with osteomyelitis. Targeted antibiotherapy for 12 weeks was conducted, with subsequent resolution of symptoms and no progression of the bone erosion. Conclusions: Atypical pathogens such as A. xylosoxidans can be the cause of chronic otitis externa. Early diagnosis and specific antibiotherapy can prevent the development of further complications, such as osteomyelitis. In these cases, otic cultures play an essential role to identify the causal germ. This is the first case of EAC osteomyelitis due to A. xylosoxidans reported to date. [ABSTRACT FROM AUTHOR]

Achromobacter xylosoxidans is an emerging nosocomial pathogen which is commonly found in the environment. In hospital settings, especially in ICU, it can be a cause of nosocomial infection. It is commonly found in the humidifiers in ICU settings and it is also commonly associated with the immunocompromised state of patient having comorbidities. The objective of the study was to study the prevalence of Achromobacter xylosoxidans and its antimicrobial sensitivity pattern. The Retrospective analysis was done of the culture reports positive for Achromobacter xylosoxidans by VITEK 2 method and its Antimicrobial sensitivity pattern was analysed from the period of September 2021 to February 2023.The maximum (54.54%) infection was seen in the age group >50 years. The maximum number (66.2%) of Achromobacter xylosoxidans were isolated from Suction tip, followed by blood (8%) and Tracheal Tip (5%). Surgical ICU contributed to the maximum number of infections i.e. 40.2%, followed by Respiratory ICU (22.1%). Maximum sensitivity was seen for Cotrimoxazole and Meropenem (around 80%), followed by Cefoperazone-Sulbactam (74%), Imipenem, Levofloxacin, Ceftazidime (around 65%). The sensitivity was minimal for Ceftriaxone (0%), Aztreonam (1.3%), and Gentamicin (5.2%). The most common risk factors/ comorbidities associated with Achromobacter infections was recent ICU admission (87.01%). The antibiotic sensitivity trends to all the antibiotics used, declined from 2021 to 2022. The antibiotic of choice to our conclusion is Cotrimoxazole, followed by Piperacillin-Tazobactam. Colistin should be kept as a reserve drug for the last resort treatment. The bacteria should not be ignored as it can lead to various opportunistic infections in immunocompromised patients, causing hindrance in the treatment.

Pyomyositis is a bacterial infection occurring mainly in skeletal muscles. It is most commonly caused by Staphylococcus aureus with initial symptoms including muscle pain, swelling, and site tenderness. When available, the most accurate technique to determine the extent and the specific location of disease is the magnetic resonance imaging. Successful management includes early recognition, timely surgical debridement or drainage, and appropriate antibiotic therapy. This case report describes a case of Mycobacterium fortuitum pyomyositis in an elderly male associated with challenges of successful diagnosis.

Green nail syndrome (GNS) is a persistent greenish pigmentation of the nail plate, originally described in 1944 by Goldman and Fox, due to Pseudomonas aeruginosa infection. Recently, pulmonary co-infection of P. aeruginosa and Achromobacter spp. has been described in patients with cystic fibrosis. Achromobacter xylosoxidans is a multidrug-resistant (MDR) pathogen involved in lung and soft tissue skin infections. Both Achromobacter xylosoxidans and P. aeruginosa are mainly found in humid environments or in water. There are no recognized co-infections due to P. aeruginosa and A. xylosoxidans in the skin and appendages. We describe two cases of GNS, the first due to P. aeruginosa associated with Achromobacter xylosoxidans; the other due to MDR P. aeruginosa, both successfully treated with topical ozenoxacin 1% cream daily for 12 weeks. The clinical management of GNS can be confusing, especially when the bacterial culture result is inconsistent or when non-Pseudomonas bacteria are isolated. In our case, due to the co-infection of P. aeruginosa and Achromobacter spp., local treatment with ozenoxacin – the first nonfluorinated quinolone – could be a safe and effective treatment in case of MDR nail infections. Further studies are required to evaluate clinical isolation from nail infections and the co-presence of P. aeruginosa and A. xylosoxidans.

ABSTRACTAchromobacter spp. are opportunistic pathogens of environmental origin increasingly isolated in patients with underlying conditions like cystic fibrosis (CF). Despite recent advances, their virulence factors remain incompletely studied, and siderophore production has not yet been investigated in this genus. The aim of this study was to evaluate the production of siderophores in a large collection of Achromobacter spp. and evaluate the variability according to the origin of the strain and species. A total of 163 strains were studied, including 128 clinical strains (CF and non-CF patients) and 35 strains of environmental origin. Siderophores were quantified by the liquid chrome azurol-sulphonate assay. Species were identified by nrdA gene-based phylogeny. Strains were assigned to 20 species, with Achromobacter xylosoxidans being the most represented (51.5% of strains). Siderophore production was observed in 72.4% of the strains, with amounts ranging from 10.1% to 90% siderophore units. A significantly higher prevalence of siderophore-producing strains and greater production of siderophores were observed for clinical strains compared with strains of environmental origin. Highly variable observations were made according to species: A. xylosoxidans presented unique characteristics (one of the highest prevalence of producing strains and highest amounts produced, particularly by CF strains). Siderophores are important factors for bacterial growth commonly produced by members of the Achromobacter genus. The significance of the observations made during this study must be further investigated. Indeed, the differences observed according to species and the origin of strains suggest that siderophores may represent important determinants of the pathophysiology of Achromobacter spp. infections and also contribute to the particular epidemiological success of A. xylosoxidans in human infections.IMPORTANCEAchromobacter spp. are recognized as emerging opportunistic pathogens in humans with various underlying diseases, including cystic fibrosis (CF). Although their pathophysiological traits are increasingly studied, their virulence factors remain incompletely described. Particularly, siderophores that represent important factors of bacterial growth have not yet been studied in this genus. A population-based study was performed to explore the ability of members of the Achromobacter genus to produce siderophores, both overall and in relevant subgroups (Achromobacter species; strain origin, either clinical—from CF or non-CF patients—or environmental). This study provides original data showing that siderophore production is a common trait of Achromobacter strains, particularly observed among clinical strains. The major species, Achromobacter xylosoxidans, encompassed both one of the highest prevalence of siderophore-producing strains and strains producing the largest amounts of siderophores, particularly observed for CF strains. These observations may represent additional advantages accounting for the epidemiological success of this species.

Achromobacter xylosoxidans is a common bacterium that rarely causes pneumonia. Determining whether A. xylosoxidans is the cause of lung infection in patients suspected of having chronic infectious lung disease is challenging because it can present with colonization. We report a case of a 56‐year‐old immunocompetent woman suspected of having non‐tuberculous mycobacteria (NTM) infection on imaging examination and monitored for 3 years. Sputum examinations revealed A. xylosoxidans several times, and it was determined to be a colonization. A. xylosoxidans was isolated from bronchial lavage fluid and aspirated sputum, but no evidence of NTM was observed. She was diagnosed with A. xylosoxidans infection and given ceftazidime for 2 weeks. Her symptoms and imaging findings improved rapidly after treatment, without recurrences. A. xylosoxidans rarely causes chronic lower respiratory tract infections similar to NTM in immunocompetent patients. A. xylosoxidans may be a target for treatment when detected in lower respiratory tract specimens. [ABSTRACT FROM AUTHOR]

Introduction: With the emergence of the multi-drug resistant bacteria that threaten the human health, novel antimicrobial compounds from natural environment have been increasingly explored. Tasik Cermin is a lake completely covered by karst towers and hills and lacks any inflow or outflow of water making it an oligotrophic environment with limited nutrient availability. Increased competition among microorganisms leads to production of antimicrobial compounds that can inhibit the growth of its competitor. Thus, the aim of this study is to assess antimicrobial activity of bacterial isolates from Tasik Cermin and identify the most resistant isolate. Methods: The isolates were tested against five test bacteria: Staphylococcus aureus, Bacillus subtilis, Streptococcus pneumoniae, Escherichia coli, and Proteus vulgaris by primary screening through perpendicular streak method, secondary screening followed by MIC and MBC and the most resistant bacteria was identified by molecular identification. Results: The result indicates that only one isolate (Isolate TC1A) was able to show potential antimicrobial activity against P. vulgaris and S. pneumoniae. This isolate was further tested by secondary screening through agar well diffusion method and inhibition zone were observed on P. vulgaris (14.97 ± 0.05), E. coli (9.23 ± 0.25) and S. pneumoniae (14.93 ± 0.12). Statistical analysis by One-Way ANOVA and Tukey test method indicates that inhibition zone of E. coli is significantly different as compared to S. pneumoniae and P. vulgaris. Molecular identification revealed that the isolate TC1A was identified as Achromobacter sp. with 97.68% similarity percentage. Conclusion: This finding shows that bacterial isolates from under-explored areas have the potential of producing novel antimicrobial compounds. [ABSTRACT FROM AUTHOR]

Achromobacter xylosoxidans is an emerging nosocomial pathogen which is commonly found in the environment. In hospital settings, especially in ICU, it can be a cause of nosocomial infection. It is commonly found in the humidifiers in ICU settings and it is also commonly associated with the immunocompromised state of patient having comorbidities. The objective of the study was to study the prevalence of Achromobacter xylosoxidans and its antimicrobial sensitivity pattern. The Retrospective analysis was done of the culture reports positive for Achromobacter xylosoxidans by VITEK 2 method and its Antimicrobial sensitivity pattern was analysed from the period of September 2021 to February 2023.The maximum (54.54%) infection was seen in the age group >50 years. The maximum number (66.2%) of Achromobacter xylosoxidans were isolated from Suction tip, followed by blood (8%) and Tracheal Tip (5%). Surgical ICU contributed to the maximum number of infections i.e. 40.2%, followed by Respiratory ICU (22.1%). Maximum sensitivity was seen for Cotrimoxazole and Meropenem (around 80%), followed by Cefoperazone-Sulbactam (74%), Imipenem, Levofloxacin, Ceftazidime (around 65%). The sensitivity was minimal for Ceftriaxone (0%), Aztreonam (1.3%), and Gentamicin (5.2%). The most common risk factors/ comorbidities associated with Achromobacter infections was recent ICU admission (87.01%). The antibiotic sensitivity trends to all the antibiotics used, declined from 2021 to 2022. The antibiotic of choice to our conclusion is Cotrimoxazole, followed by Piperacillin-Tazobactam. Colistin should be kept as a reserve drug for the last resort treatment. The bacteria should not be ignored as it can lead to various opportunistic infections in immunocompromised patients, causing hindrance in the treatment. [ABSTRACT FROM AUTHOR]

Achromobacter xylosoxidans is a Gram-negative, aerobic, non-fermenting bacillus mainly responsible for nosocomial infections. We report the first case of community-acquired spondylodiscitis caused by Achromobacter xylosoxidans in a 61-year-old woman, immunocompromised with necrotizing dermohypodermitis of the right lower limb successfully treated with ertapenem and ciprofloxacin.

Background: Cavendish (AAA) banana plant (Musa spp.) worldwide cultivated crop harbors many endophytic bacteria. Endophytic bacteria are those that live inside plant tissues without producing any visible symptoms of infection. Results: Endophytic bacterium (MRH 11), isolated from root tissue of Musa spp.was identified as Achromobacter xylosoxidans (ON955872) which showed positive effects in IAA production, phosphate solubilization, catalase production. A. xylosoxidans also showed in vitro antagonism against Curvularia lunata causing leaf spot disease of Cavendish (AAA) banana (G-9 variety). The GC-MS analysis of culture filtrate of A. xylosoxidans (ON955872) confirmed this finding. GC-MS analysis was carried by using two solvent etheyl acetate and chloroform and it showed several antifungal compounds. The identification of these bioactive secondary metabolites compounds was based on the peak area, retention time, molecular weight, molecular formula and antimicrobial actions. GC-MS analysis result revealed the presence of major components including Cyclododecane, 1-Octanol, Cetene, Diethyl phthalate. In vivo test to banana plants was carried out in separate field as well as in potted conditions. Appearance of leaf spots after foliar spray of spore of pathogen and reduction in leaf spots after application of bacterial suspension was found. Conclusion: The present study has highlighted the role of endophytic bacterium as antagonist to the pathogen Curvularia lunata. [ABSTRACT FROM AUTHOR]

Waste lubricant oil (WLO) is a critical environmental issue because of its recycle and disposal challenges. A potent biosurfactant-producing bacterial strain was isolated by the enrichment culture technique using WLO as the sole carbon source from the oil-contaminated soils. The strain was identified as Achromobacter xylosoxidans (NCBI GenBank accession number: MW673656) based on the morphological, biochemical, and 16S rRNA gene sequencing. The preliminary characterization of the produced biosurfactant by biochemical methods revealed its glycolipid nature. The strain possessed extensive biodegradative potential and degraded various components present in WLO. The gas chromatography-mass spectrometry (GC-MS) analysis showed that the strain could degrade hydrocarbons (C7-C22) and diethyl phthalate, a priority pollutant, with a relative degradation of 43.87% within 7 days of incubation. The biodegradation of WLO by the strain confers its use in the bioremediation of oil-polluted environments, and the simultaneous biosurfactant production is undoubtedly a step toward greener technology. [ABSTRACT FROM AUTHOR]

BACKGROUND: Prosthetic valve endocarditis (PVE) represents a life-threatening infection that may complicate valve replacement, associated with high morbidity and mortality. There is no clinical presentation characteristic of PVE. Causative agents of community-acquired PVE include endogenous microbiota, such as viridans group streptococci and enterococci, similar to native valve endocarditis etiology. An increasing number of recent publications have addressed the pathogenic role of Achromobacter xylosoxidans, a causative agent of a wide range of opportunistic infections in immunocompromised patients and healthcare‐associated infections. However, it has only rarely been associated with the development of endocarditis, most commonly reported in patients with severe immune impairment caused by various pathological conditions or in very frail elderly patients. CASE PRESENTATION: A severe aortic valve graft infection by A. xylosoxidans is described with a literature review. A 69-year-old man with multiple serious comorbidities developed severe aortic endocarditis due to A. xylosoxydans after aortic valve replacement surgery. Only treatment with daptomycin, gentamicin and ampicillin allowed to obtain long-term clinical improvement. CONCLUSIONS: An extensive review of the literature on cases of A. xylosoxydans endocarditis was conducted. Our review highlights that PVE due to A. xylosoxydans has a high mortality.

ABSTRACT Achromobacter is a genus of Gram-negative rods, which can cause persistent airway infections in people with cystic fibrosis (CF). The knowledge about virulence and clinical implications of Achromobacter is still limited, and it is not fully established whether Achromobacter infections contribute to disease progression or if it is a marker of poor lung function. The most commonly reported Achromobacter species in CF is A. xylosoxidans. While other Achromobacter spp. are also identified in CF airways, the currently used Matrix-Assisted Laser Desorption/Ionization Time Of Flight Mass Spectrometry (MALDI-TOF MS) method in routine diagnostics cannot distinguish between species. Differences in virulence between Achromobacter species have consequently not been well studied. In this study, we compare phenotypes and proinflammatory properties of A. xylosoxidans, A. dolens, A. insuavis, and A. ruhlandii using in vitro models. Bacterial supernatants were used to stimulate CF bronchial epithelial cells and whole blood from healthy individuals. Supernatants from the well-characterized CF-pathogen Pseudomonas aeruginosa were included for comparison. Inflammatory mediators were analyzed with ELISA and leukocyte activation was assessed using flow cytometry. The four Achromobacter species differed in morphology seen in scanning electron microscopy (SEM), but there were no observed differences in swimming motility or biofilm formation. Exoproducts from all Achromobacter species except A. insuavis caused significant IL-6 and IL-8 secretion from CF lung epithelium. The cytokine release was equivalent or stronger than the response induced by P. aeruginosa. All Achromobacter species activated neutrophils and monocytes ex vivo in a lipopolysaccharide (LPS)-independent manner. Our results indicate that exoproducts of the four included Achromobacter species do not differ consistently in causing inflammatory responses, but they are equally or even more capable of inducing inflammation compared with the classical CF pathogen P. aeruginosa. IMPORTANCE Achromobacter xylosoxidans is an emerging pathogen among people with cystic fibrosis (CF). Current routine diagnostic methods are often unable to distinguish A. xylosoxidans from other Achromobacter species, and the clinical relevance of different species is still unknown. In this work, we show that four different Achromobacter species relevant to CF evoke similar inflammatory responses from airway epithelium and leukocytes in vitro, but they are all equally or even more proinflammatory compared to the classic CF-pathogen Pseudomonas aeruginosa. The results suggest that Achromobacter species are important airway pathogens in CF, and that all Achromobacter species are relevant to treat.

Chronic lung infections in cystic fibrosis (CF) patients are triggered by multidrug-resistant bacteria such as Pseudomonas aeruginosa, Achromobacter xylosoxidans, and Stenotrophomonas maltophilia. The CF airways are considered ideal sites for the colonization and growth of bacteria and fungi that favor the formation of mixed biofilms that are difficult to treat. The inefficacy of traditional antibiotics reinforces the need to find novel molecules able to fight these chronic infections. Antimicrobial peptides (AMPs) represent a promising alternative for their antimicrobial, anti-inflammatory, and immunomodulatory activities. We developed a more serum-stable version of the peptide WMR (WMR-4) and investigated its ability to inhibit and eradicate C. albicans, S. maltophilia, and A. xylosoxidans biofilms in both in vitro and in vivo studies. Our results suggest that the peptide is able better to inhibit than to eradicate both mono and dual-species biofilms, which is further confirmed by the downregulation of some genes involved in biofilm formation or in quorum-sensing signaling. Biophysical data help to elucidate its mode of action, showing a strong interaction of WMR-4 with lipopolysaccharide (LPS) and its insertion in liposomes mimicking Gram-negative and Candida membranes. Our results support the promising therapeutic application of AMPs in the treatment of mono- and dual-species biofilms during chronic infections in CF patients. [ABSTRACT FROM AUTHOR]

Objective and design: Our research aimed to investigate the role of CD14 in pulmonary infection by Achromobacter xylosoxidans in an experimental murine model. Methods: C57Bl/6 or CD14-deficient mice were infected intratracheally with non-lethal inoculum of A. xylosoxidans. At times 1, 3 and 7 days after infection, lungs, bronchoalveolar lavage and blood were collected. CD14 gene expression was determined by RT-PCR. The bacterial load in the lungs was assessed by counting colony forming units (CFU). Cytokines, chemokines, lipocalin-2 and sCD14 were quantified by the ELISA method. Inflammatory infiltrate was observed on histological sections stained with HE, and leukocyte subtypes were assessed by flow cytometry. In another set of experiments, C57Bl/6 or CD14-deficient mice were inoculated with lethal inoculum and the survival rate determined. Results: CD14-deficient mice are protected from A. xylosoxidans-induced death, which is unrelated to bacterial load. The lungs of CD14-deficient mice presented a smaller area of tissue damage, less neutrophil and macrophage infiltration, less pulmonary edema, and a lower concentration of IL-6, TNF-α, CXCL1, CCL2 and CCL3 when compared with lungs of C57Bl/6 mice. We also observed that A. xylosoxidans infection increases the number of leukocytes expressing mCD14 and the levels of sCD14 in BALF and serum of C57Bl/6-infected mice. Conclusions: In summary, our data show that in A. xylosoxidans infection, the activation of CD14 induces intense pulmonary inflammatory response resulting in mice death. [ABSTRACT FROM AUTHOR]

An 83-year-old male with a history of radial keratotomy and laser-assisted in situ keratomileusis (LASIK) presented with symptoms of a non-resolving corneal ulcer in the right eye that had been present for five months. The patient was treated with antibacterial, antiviral, and antifungal medications over that period, with multiple recurrences that prompted referral to our tertiary center for management. Following a 48-hour cessation of all medications, a corneal biopsy was performed which grew Achromobacter xylosoxidans . In conclusion, Achromobacter xylosoxidans remains a rare cause of keratitis but should be considered in patients with a slow-progressing disease. Risk factors include previous corneal surgeries or trauma, topical steroid use, and contact lens wear. Because A. xylosoxidans grows slowly, it can have a deep impact on the cornea. To help antibiotics get into the cornea properly, epithelial debridement may be helpful. It does not respond to standard empiric antibiotic therapy. Ceftazidime and fourth-generation fluoroquinolones are better choices for treatment., Competing Interests: Human subjects: Consent for treatment and open access publication was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Sahawneh et al.)

Cystic fibrosis (CF) is a disorder causing dysfunctional ion transport resulting in the accumulation of viscous mucus. This environment fosters a chronic bacterial biofilm-associated infection in the airways. Achromobacter xylosoxidans, a gram-negative aerobic bacillus, has been increasingly associated with antibiotic resistance and chronic colonisation in CF. In this study, we aimed to create a reproducible model of CF infection using an artificial sputum medium (ASMDM-1) with bronchial (BEAS-2B) and macrophage (THP-1) cells to test A. xylosoxidans infection and treatment toxicity. This study was conducted in three distinct stages. First, the tolerance of BEAS-2B cell lines and two A. xylosoxidans strains against ASMDM-1 was optimised. Secondly, the cytotoxicity of combined therapy (CT) comprising N-acetylcysteine (NAC) and the antibiotics colistin or ciprofloxacin was tested on cells alone in the sputum model in both BEAS-2B and THP-1 cells. Third, the efficacy of CT was assessed in the context of a bacterial infection within the live cell/sputum model. We found that a model using 20% ASMDM-1 in both cell populations tolerated a colistin–NAC-based CT and could significantly reduce bacterial loads in vitro (~2 log10 CFU/mL compared to untreated controls). This pilot study provides the foundation to study other bacterial opportunists that infect the CF lung to observe infection and CT kinetics. This model also acts as a springboard for more complex co-culture models. [ABSTRACT FROM AUTHOR]

ABSTRACT: Objectives: Achromobacter xylosoxidans is widely distributed in the environment and is increasingly recognised as a significant nosocomial pathogen in healthcare settings. However, the genomic and phylogenetic characteristics of this pathogen are not fully understood. Here we report the first genome sequence of a multidrug-resistant A. xylosoxidans ST273 strain (MTYH1) isolated from a wound infection in China. Methods: Whole-genome sequencing of the strain was performed using an Illumina NovaSeq 6000 platform. Generated short reads were de novo assembled into contigs using SPAdes v.3.13.0. Antimicrobial resistance genes (ARGs) were identified using ResFinder 4.0. Phylogenetic analysis was conducted using NJ/UPGMA phylogeny (MAFFT v.7) based on core genome single nucleotide polymorphism data. Results: The draft genome sequence of A. xylosoxidans ST273 strain MTYH1 consists of 45 contigs comprising 6 643 045 bp with a GC content of 67.5%. According to the Achromobacter spp. multilocus sequence typing (MLST) scheme, MTYH1 belongs to ST273. MTYH1 is resistant to aminoglycosides, ciprofloxacin, aztreonam and cephalosporins. Five ARGs belonging to three different classes were identified in the genome, namely aac(6′)-IIa, ant(2′')-Ia, blaCARB-2, blaOXA-114g and sul1. Phylogenetic analysis showed that MTYH1 was not epidemiologically related to any of the strains retrieved from the NCBI GenBank database. Conclusion: We unravelled the genome sequence of multidrug-resistant A. xylosoxidans ST273 clinical strain MTYH1 recovered from a wound infection in China. Our data may help to understand the antimicrobial resistance mechanisms, genomic features and phylogenetic characteristic of this bacterial pathogen.

In this study, the effect of seed treatment with Achromobacter xylosoxidans AUM54 and glycolipid-type biosurfactants produced by this bacterial strain to suppress Ralstonia solanacearum, which causes bacterial wilt in tomato plants, was investigated. Applying biosurfactant in combination with the biosurfactant-producing bacteria reduced the R. solanacearum population on the tomato seed surface by 44% and reduced the seed infection percentage by 87%. In addition, these treatments induced resistance in tomato plants against this pathogen, evidenced by the increased activities of defence-related enzymes, such as phenylalanine ammonia-lyase, polyphenol oxidase, and peroxidase, and reduced the percentage of disease severity (DS). [ABSTRACT FROM AUTHOR]

Achromobacter xylosoxidans, previously identified as Alcaligenes xylosoxidans, is a rod-shaped, flagellated, non-fermenting Gram-negative bacterium that has the ability to cause diverse infections in humans. As a part of its intrinsic resistance to different antibiotics, Achromobacter spp. is also increasingly becoming resistant to Carbapenems. Lack of knowledge regarding the pathogen’s clinical features has led to limited efforts to develop countermeasures against infection. The current study utilized an immunoinformatic method to map antigenic epitopes (Helper T cells, B-cell and Cytotoxic-T cells) to design a vaccine construct. We found that 20 different epitopes contribute significantly to immune response instigation that was further supported by physicochemical analysis and experimental viability. The safety profile of our vaccine was tested for antigenicity, allergenicity, and toxicity against all the identified epitopes before they were used as vaccine candidates. The disulfide engineering was carried out in an area of high mobility to increase the stability of vaccine proteins. In order to determine if the constructed vaccine is compatible with toll-like receptor, the binding affinity of vaccine was investigated via molecular docking approach. With the in silico expression in host cells and subsequent immune simulations, we were able to detect the induction of both arms of the immune response, i.e., humoral response and cytokine induced response. To demonstrate its safety and efficacy, further experimental research is necessary.

Aims: This study aims to produce Achromobacter biosurfactant in nutrient-rich and nutrient-limited media. Methodology and results: This study conducted fermentation on nutrient-rich and nutrient-limited media using a minimal salt medium (MSM). Dextrose and sodium citrate were used as sole carbon supplemented with 0.5% yeast extract for nutrient-rich media, while nutrient-limited media used molasses and rice straw hydrolysate (RSH) at variations of concentrations of 100 ppm and 200 ppm. The research was performed over 120 h and evaluated from growth response, surface tension and emulsification activity. The study revealed that the best surface tension value was when 2% (w/v) sodium citrate was used as C-source and 0.5% (w/v) yeast extract as N-source, after 72 h upon incubation at 30 °C/120 rpm having 45.45 ± 2.19 mN/m with emulsification activity 24.54 ± 3.42%. Whereas the best result of the nutrient-limited medium was obtained by RSH at a concentration of 200 ppm having 48.86 ± 5.36 mN/m. Conclusion, significance and impact of study: The experiment showed that nutrient-limited medium from rice straw hydrolysate could compete with the nutrient-rich medium. The use of rice straw will contribute to the reduction of biosurfactant production costs and valorisation of agricultural waste. [ABSTRACT FROM AUTHOR]

Achromobacter xylosoxidans is an aerobic, Gram negative, non-lactose fermenting rod which inhabits soil and aquatic environments. It is uncommonly encountered in human infections. When it occurs, it is associated with nosocomial infections and infection in immunocompromised individuals. Awareness of its infectious potential is important as it is multi-drug resistant and can lead to increased mortality rates. We describe a case of skull base osteomyelitis secondary to otitis media caused by Achromobacter xylosoxidans in a diabetic patient. He responded to combination treatment with carbapenem and quinolone along with blood sugar level control. Both, the clinical disorder and the causative organism are exceptional. To the best of our knowledge, no case akin to this has been reported previously in literature.

Thomas A Lazzarini,1 Hasenin Al-khersan,1 Nimesh A Patel,1 Nicolas A Yannuzzi,1 Jaime D Martinez,1 Diego Altamirano,1 Lizt K Torres,2 Darlene Miller,1 Juan F Batlle,1,2 Guillermo Amescua,1 Harry W Flynn Jr1 1Department of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miller School of Medicine, Miami, FL, 33136, USA; 2Laser Center, Santo Domingo, Dominican RepublicCorrespondence: Thomas A LazzariniDepartment of Ophthalmology, Bascom Palmer Eye Institute, University of Miami, Miller School of Medicine, 900 NW 17th Street, Miami, FL 33136, USATel +1 305 326-6118Fax +1 305 326-6417Email txl564@miami.eduAbstract: A 79-year-old man presented to a tertiary referral center from the Dominican Republic with an opaque corneal graft and a diagnosis of chronic, recurrent culture-positive Achromobacter xylosoxidans endophthalmitis of the left eye. The patient had a history of penetrating keratoplasty for Fuchs’ dystrophy and had undergone multiple intraocular surgeries including pars plana vitrectomy and anterior chamber wash out for the diagnosis and management of chronic endophthalmitis. After being referred, the patient underwent a third PKP, removal of his intraocular lens (IOL), capsulectomy, and injection of intravitreal antibiotics. All surgical specimens demonstrated the growth of A. xylosoxidans. Five months after surgery, the graft remained clear without evidence of infection and best-corrected visual acuity was 20/350.Keywords: endophthalmitis, Achromobacter xylosoxidans, ophthalmlology, postoperative endophthalmitis, ophthalmic infection

Summary: Background: This report describes recurrent A. xylosoxidans bloodstream and PICC (peripherally-inserted central catheter) line infection in an immunocompromised patient. Presentation of Case: A 64-year-old female with acute promyelocytic leukaemia presented during a non-neutropenic febrile episode, and A. xylosoxidans was isolated from multiple PICC and peripheral blood cultures, and from the tip of the line on removal. The patient was treated with meropenem and a new PICC line was inserted after sterile blood cultures. Six weeks later, she represented with A. xylosoxidans from multiple cultures from the line. She was treated with piperacillin-tazobactam and the line was removed. There was no evidence of deep-seated infection. Further discussion revealed that the patient was using a sponge to clean, and a sleeve to cover her PICC-line while bathing. A. xylosoxidans was cultured from both the sponge and the swab. Whole Genome Sequencing performed on two blood culture isolated and both environmental isolates confirmed all four isolates were indistinguishable. The patient was advised not to use the sponge/sleeve in future and we have incorporated specific advice in this regard into our patient information. Discussion: Achromobacter xylosoxidans is an aerobic, non-lactose fermenting gram-negative bacillus usually considered an opportunistic pathogen. It is associated with infection in immunocompromised patients, and is an emerging pathogen in catheter-related infections, sometimes associated with contaminated water. Conclusion: This case of recurrent A. xylosoxidans line infection highlights diagnostic and management challenges associated with catheter-related infections. Treatment is challenging because of intrinsic and acquired resistance mechanisms. Empiric treatment with anti-pseudomonal penicillins or carbapenems with line removal is typically required.

Background: Achromobacter xylosoxidans (AX) is an aerobic Gram-negative opportunistic bacteria known to inhabit various environments and is most commonly associated with nosocomial infections in immune-compromised patients. Although rare, AX can cause a variety of neurological infections, such as meningitis, ventriculitis, and osteomyelitis. Intravascular catheters, intrathecal pumps, and contaminated surgical instruments are potential vectors for such patients., Case Description: Here, we present a unique case of multidrug-resistant AX-positive meningitis secondary to infection of a nonfunctional intrathecal narcotic pump. The patient has a complex past medical history leading up to infection, and care was significantly compromised by homelessness and inflammatory bowel disease (IBD). Treatment included catheter removal and antibiotics., Conclusion: Patients who suffer from homelessness or IBD show a possible increased risk of this infection. This case emphasizes the need for increased care regarding these patients, along with describing the complications and timeline when treating this rare type of meningitis., Competing Interests: There are no conflicts of interest., (Copyright: © 2024 Surgical Neurology International.)

Achromobacter xylosoxidans is a rod-shaped Gram-negative bacterium linked with causing several infections which mostly includes hematological malignancies. It has been recently reported to be associated with the development and progression of lung cancer and is an emerging respiratory disease-causing bacterium. The treatment of individuals infected with A. xylosoxidans bacteremia is difficult due to the fact that this pathogen has both intrinsic and acquired resistance mechanisms, typically resulting in a phenotype of multidrug resistance (MDR). Efforts are needed to design effective therapeutic strategies to curtail the emergence of this bacterium. Computational vaccine designing has proven its effectiveness, specificity, safety, and stability compared to conventional approaches of vaccine development. Therefore, the whole proteome of A. xylosoxidans was screened for the characterization of potential vaccine targets through subtractive proteomics pipeline for therapeutics design. Annotation of the whole proteome confirmed the three immunogenic vaccine targets, such as (E3HHR6), (E3HH04), and (E3HWA2), which were used to map the putative immune epitopes. The shortlisted epitopes, specific against Cytotoxic T Lymphocytes, Helper T-cell Lymphocytes, and linear B-Cell, were used to design the mRNA and multi-epitopes vaccine (MEVC). Initial validations confirmed the antigenic and non-allergenic properties of these constructs, followed by docking with the immune receptor, TLR-5, which resulted in robust interactions. The interaction pattern that followed in the docking complex included formation of 5 hydrogen bonds, 2 salt bridges, and 165 non-bonded contacts. This stronger binding affinity was also assessed through using the mmGBSA approach, showing a total of free binding energy of −34.64 kcal/mol. Further validations based on in silico cloning revealed a CAI score of 0.98 and an optimal percentage of GC contents (54.4%) indicated a putatively higher expression of the vaccine construct in Escherichia coli. Moreover, immune simulation revealed strong antibodies production upon the injection of the designed MEVC that resulted in the highest peaks of IgM+ IgG production (>3,500) between 10 and 15 days. In conclusion the current study provide basis for vaccine designing against the emerging A. xylosoxidans, which demands further experimental studies for in vitro and in vivo validations.

We report a rare case of recurrent Achromobacter xylosoxidans bacteremia in an older woman in 2014 and 2020. During the more recent bacteremia, a diagnosis of mitral endocarditis was made. The patient could not have surgery because of severe comorbidities and a high operative risk. Combined antibiotic therapy was given with piperacillin/tazobactam and trimethoprim/sulfamethoxazole (TMP/SMX). Antibiotic therapy was administered for six weeks with a good response, but the patient relapsed after six days with A. xylosoxidans bacteremia and cardiac decompensation. Antibiotic therapy was resumed, using meropenem and TMP/SMX, but the patient died one month after the recurrence. We review the 22 cases of A. xylosoxidans endocarditis that have been described in the literature.

Copyright of Journal of South China Agricultural University is the property of Gai Kan Bian Wei Hui and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Egyptian Journal of Botany is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Treatment options for Achromobacter xylosoxidans are limited. Eight cystic fibrosis patients with A. xylosoxidans were treated with 12 cefiderocol courses. Pretreatment in vitro resistance was seen in 3 of 8 cases. Clinical response occurred after 11 of 12 treatment courses. However, microbiologic relapse was observed after 11 of 12 treatment courses, notably without emergence of resistance. [ABSTRACT FROM AUTHOR]

• This study aimed to construct an epitope-based vaccine candidate using immunoinformatic techniques. • A. xylosoxidans was isolated from an auto workshop in Lahore, and its identification was confirmed through 16S rRNA amplification and bioinformatic analysis. • Two protein targets with GenBank accession numbers AKP90890.1 and AKP90355.1 were selected for the vaccine construct. • The vaccine construct demonstrated structural stability, thermostability, solubility, and hydrophilicity. • This epitope-based vaccine could serve as the first preventive immunotherapy against A. xylosoxidans infections, addressing this bacterium's health and financial burdens. • The findings demonstrate the value of employing immunoinformatic tools in vaccine development, paving the way for more precise and tailored approaches to combating microbial threats. Achromobacter xylosoxidans is an aerobic, catalase-positive, non-pigment-forming, Gram-negative, and motile bacterium. It potentially causes a wide range of human infections in cystic fibrosis and non-cystic fibrosis patients. However, developing a safe preventive or therapeutic solution against A. xylosoxidans remains challenging. This study aimed to construct an epitope-based vaccine candidate using immunoinformatic techniques. A. xylosoxidans was isolated from an auto workshop in Lahore, and its identification was confirmed through 16S rRNA amplification and bioinformatic analysis. Two protein targets with GenBank accession numbers AKP90890.1 and AKP90355.1 were selected for the vaccine construct. Both proteins exhibited antigenicity, with scores of 0.757 and 0.580, respectively and the epitopes were selected based on the IC50 value using the ANN 4.0 and NN-align 2.3 epitope prediction method for MHC I and MHC II epitopes respectively and predicted epitopes were analyzed for antigenicity, allergenicity and pathogenicity. The vaccine construct demonstrated structural stability, thermostability, solubility, and hydrophilicity. The vaccine produced 250 B-memory cells per mm3 and approximately 16,000 IgM + IgG counts, indicating an effective immune response against A. xylosoxidans. Moreover, the vaccine candidate interacted stably with toll-like receptor 5, a pattern recognition receptor, with a confidence score of 0.98. These results highlight the potency of the designed vaccine candidate, suggesting its potential to withstand rigorous in vitro and in vivo clinical trials. This epitope-based vaccine could serve as the first preventive immunotherapy against A. xylosoxidans infections, addressing this bacterium's health and financial burdens. The findings demonstrate the value of employing immunoinformatic tools in vaccine development, paving the way for more precise and tailored approaches to combating microbial threats. [ABSTRACT FROM AUTHOR]

Achromobacter xylosoxidans is a gram-negative bacterium that can oxidize xylose. It is commonly found in contaminated soil and water but does not normally infect immunocompetent humans. We report a case of a cavitary lung lesion associated with community-acquired A. xylosoxidans infection, which mimicked pulmonary tuberculosis or lung cancer in an immunocompetent man. The patient was hospitalized due to hemoptysis, and chest computed tomography (CT) revealed a cavitary lesion in the superior segment of the left lower lobe. We performed bronchoscopy and bronchial washing, and subsequent bacterial cultures excluded pulmonary tuberculosis and identified A. xylosoxidans. We performed antibiotic sensitivity testing and treated the patient with a 6-week course of amoxicillin/clavulanate. After 2 months, follow-up chest CT revealed complete resolution of the cavitary lesion.

Cystic fibrosis (CF) is a disorder causing dysfunctional ion transport resulting in the accumulation of viscous mucus. This environment fosters a chronic bacterial biofilm-associated infection in the airways. Achromobacter xylosoxidans, a gram-negative aerobic bacillus, has been increasingly associated with antibiotic resistance and chronic colonisation in CF. In this study, we aimed to create a reproducible model of CF infection using an artificial sputum medium (ASMDM-1) with bronchial (BEAS-2B) and macrophage (THP-1) cells to test A. xylosoxidans infection and treatment toxicity. This study was conducted in three distinct stages. First, the tolerance of BEAS-2B cell lines and two A. xylosoxidans strains against ASMDM-1 was optimised. Secondly, the cytotoxicity of combined therapy (CT) comprising N-acetylcysteine (NAC) and the antibiotics colistin or ciprofloxacin was tested on cells alone in the sputum model in both BEAS-2B and THP-1 cells. Third, the efficacy of CT was assessed in the context of a bacterial infection within the live cell/sputum model. We found that a model using 20% ASMDM-1 in both cell populations tolerated a colistin–NAC-based CT and could significantly reduce bacterial loads in vitro (~2 log10 CFU/mL compared to untreated controls). This pilot study provides the foundation to study other bacterial opportunists that infect the CF lung to observe infection and CT kinetics. This model also acts as a springboard for more complex co-culture models.

Achromobacter xylosoxidans (A. xylosoxidans)  is an opportunistic pathogen that is responsible for various nosocomial and community-acquired infections. It is often found in patients with cystic fibrosis or chronic lung diseases. Here, a 70-year-old female patient presented to an emergency department with complaints of diffuse abdominal pain and distension, on and off giddiness, and generalized body pain for one month with a known case of diabetes and hypertension. The patient had no history of nausea, vomiting, constipation/loose stools, or fever at the time of arrival. Then, the patient was admitted with a provisional diagnosis of incisional hernia. However, the patient developed a fever after she had undergone surgery for an incisional hernia. The blood culture reveals the growth of A. xylosoxidans.  The patient responded well to treatment with intravenous antibiotics piperacillin/tazobactam and meropenem for five days. The literature on bacteremia caused by  A. xylosoxidans  in incisional hernia patients is reviewed in this study, along with the distinct antimicrobial susceptibility pattern., Competing Interests: Human subjects: Consent was obtained or waived by all participants in this study. Conflicts of interest: In compliance with the ICMJE uniform disclosure form, all authors declare the following: Payment/services info: All authors have declared that no financial support was received from any organization for the submitted work. Financial relationships: All authors have declared that they have no financial relationships at present or within the previous three years with any organizations that might have an interest in the submitted work. Other relationships: All authors have declared that there are no other relationships or activities that could appear to have influenced the submitted work., (Copyright © 2024, Dhakshna Murthi et al.)

Contamination of crop seeds and feed with Aspergillus flavus and its associated aflatoxins presents a significant threat to human and animal health due to their hepatotoxic and carcinogenic properties. To address this challenge, researchers have screened for potential biological control agents in peanut soil and pods. This study identified a promising candidate, a strain of the nonpigmented bacterium, Achromobacter xylosoxidans ZJS2-1, isolated from the peanut rhizosphere in Zhejiang Province, China, exhibiting notable antifungal and antiaflatoxin activities. Further investigations demonstrated that ZJS2-1 active substances (ZAS) effectively inhibited growth at a MIC of 60 μL/mL and nearly suppressed AFB1 production by 99%. Metabolomic analysis revealed that ZAS significantly affected metabolites involved in cell wall and membrane biosynthesis, leading to compromised cellular integrity and induced apoptosis in A. flavus through the release of cytochrome c . Notably, ZAS targeted SrbA, a key transcription factor involved in ergosterol biosynthesis and cell membrane integrity, highlighting its crucial role in ZJS2-1's biocontrol mechanism. Moreover, infection of crop seeds and plant wilt caused by A. flavus can be efficiently alleviated by ZAS. Additionally, ZJS2-1 and ZAS demonstrated significant inhibitory effects on various Aspergillus species, with inhibition rates ranging from 80 to 99%. These findings highlight the potential of ZJS2-1 as a biocontrol agent against Aspergillus species, offering a promising solution to enhance food safety and protect human health.

Background: Achromobacter xylosoxidans is a Gram-negative opportunistic aerobe, usually causing nosocomial infections in immunocompromised patients with manifestations including bacteremia, pneumonia, and catheter-related infections. However, A. xylosoxidans have not yet been reported to cause biliary system infections., Case Summary: A 72-year-old woman presented to the outpatient department of our hospital with a chief complaint of jaundice. Computed tomography of her abdomen revealed the presence of a mass of approximately 2.4 cm in the hilar portion of the common hepatic duct, consistent with hilar cholangiocarcinoma. We performed endoscopic retrograde cholangiopancreatography (ERCP) to decompress the obstructed left and right intrahepatic ducts (IHDs) and placed 10 cm and 11 cm biliary stents in the left and right IHDs, respectively. However, the day after the procedure, the patient developed post-ERCP cholangitis as the length of the right IHD stent was insufficient for proper bile drainage. The blood culture of the patient tested positive for A. xylosoxidans . Management measures included the replacement of the right IHD stent (11 cm) with a longer one (12 cm) and administering culture-directed antibiotic therapy, solving the cholangitis-related complications. After the cholangitis had resolved, the patient underwent surgery for hilar cholangiocarcinoma and survived for 912 d without recurrence., Conclusion: A. xylosoxidans -induced biliary system infections are extremely rare. Clinical awareness of physicians and endoscopists is required as this rare pathogen might cause infection after endoscopic procedures., Competing Interests: Conflict-of-interest statement: The authors have no conflicts of interest to declare., (©The Author(s) 2024. Published by Baishideng Publishing Group Inc. All rights reserved.)

Intrastromal antibiotic injections are a type of treatment that can be very useful in bacterial keratitis refractory to topical antibiotics. We present the case of a 44-year-old woman with an infiltrate in a laser in situ keratomiuleusis (LASIK) flap and growth of Achromobacter xylosoxidans, who was treated with topical ceftazidime for 1 month. However, after discontinuation of the antibiotic, there was a worsening with growth of the same germ. Topical treatment was reintroduced and, due to suspicion of germ reservoir, it was decided to give three cycles of intrastromal ceftazidime injections, the last one also with moxifloxacin, with good results. After 4 months asymptomatic and without treatment at the moment, no signs of recurrence have been observed. This case supports the usefulness of intraestromal injections in refractory cases to the topical medication., (Copyright © 2024 Sociedad Española de Oftalmología. Published by Elsevier España, S.L.U. All rights reserved.)