Search

Objectives We sought to integrate a VEB-1-encoding gene cassette into the integron of the MDR region of genomic islands (GIs) harboured by Proteus mirabilis strains after antibiotic exposure. Methods An IncP1 plasmid from Achromobacter xylosoxidans carrying the cassette array dfrA14–blaVEB-1–aadB was introduced by conjugation into five strains of P. mirabilis: PmBRI, PmABB, PmSCO and Pm2CHAMA harbouring Salmonella GI 1 and PmESC harbouring Proteus GI 1. Circular intermediates of the cassettes were amplified by PCR. blaVEB-harbouring P. mirabilis were exposed to increasing concentrations of ceftazidime each day. Presence of blaVEB-1 in the GI was assessed by PCR. The complete MDR regions were mapped and sequenced in positive clones. Results Circular intermediates were detected for dfrA14 and blaVEB-1–aadB and dfrA14–blaVEB-1–aadB cassettes arrays in A. xylosoxidans, and for aadA2 in P. mirabilis. Insertion of blaVEB-1 into the GIs occurred under ceftazidime pressure. In all cases, the three cassettes from IncP1 were integrated. They replaced the cassette array of PmBRI, PmABB and PmSCO in which floRc, tet(A)G and blaPSE-1 were conserved, whereas they replaced an integron and the IS26-flanked region in Pm2CHAMA. In PmESC, they only replaced aadB, with aadA2 being conserved. blaVEB-1 integration occurred just after conjugation for Pm2CHAMA but required ceftazidime exposure for the other strains. Conclusion Homologous recombination of gene cassettes conferring resistance to clinically important antibiotics may occur under antibiotic pressure between an integron located on a plasmid and a co-resident GI. This feature participates in the acquisition, maintenance and spread of antibiotic resistance genes.

The focus of the present study is to isolate and identify magnetotactic bacteria from fresh water sediments in Salem region, Tamil Nadu. Fresh water sediments were collected and characterized by X-ray diffraction to detect the crystalline nature of particles. Totally 12 isolates were screened for the metal biosorption efficiency in modified nutrient agar plates with 10 mg (lower concentration) of four different metals viz., manganese chloride, zinc sulphate, copper sulphate and potassium dichromate. Followed by testing their ability to tolerate higher concentration of metals viz., 20 mg, 30 mg, 50 mg, 70 mg, 90 mg and 150 mg/50 ml was analyzed. Only four bacteria survived the highest concentration of manganese and zinc (3000 µg/ml), CuSO4 and K2Cr2O7 at a concentration of 1400 µg/ml and 1800 µg/ml, respectively. The four bacterial strains Stenotrophomonas maltophilia, two Pseudomonas aeruginosa strains and Achromobacter xylosoxidans were grown in modified nutrient broth (NB) and Luria Bertani (LB) incorporated with metals such as manganese, zinc, copper and chromium and tested for their efficacy to sustain metal stress. Since the two bacterial strains (SBY and KY1) were able to grow in both medium with a potential to with stand higher metal concentration these strains were further studied. A metal tolerant magnetotactic bacterial strain Pseudomonas aeruginosa SBY was confirmed by TEM analysis to detect the accumulated metal within the cell. As bacterial strains were capable of tolerating higher concentration of metal, they may have a vital role in environmental bioremediation.

Elaborating the plant hormone catabolic activities of bacteria is important for developing a detailed understanding of plant-microbe interactions. In this work, the plant hormone catabolic and plant growth promotion activities of Achromobacter xylosoxidans SOLR10 and A. insolitus AB2 are described. The genome sequences of these strains were obtained and analysed in detail, revealing the genetic mechanisms behind its multiple plant hormone catabolism abilities. Achromobacter strains catabolized indoleacetic acid (IAA) and phenylacetic acid (PAA) (auxins); salicylic acid (SA) and its precursor, benzoic acid (BA); and the ethylene precursor 1-aminocyclopropane-1-carboxylate (ACC). The inoculation of cucumber plants resulted in increased plant growth and development, indicating the beneficial properties of SOLR10 and AB2 strains. Genomic analysis demonstrated the presence of IAA, PAA and BA degradation gene clusters, as well as the nag gene cluster (SA catabolism) and the acdS gene (ACC deaminase), in the genomes of strains SOLR10 and AB2. Additionally, detailed analysis revealed that plant hormone catabolism genes were commonly detected in the Achromobacter genus but were mostly absent in the Bordetella genus, consistent with the notion that Achromobacter evolved in soils in close association with its plant hosts.

Geranium (Pelargonium graveolens) is a strongly aromatic medicinal plant with increasing market demand. The present study demonstrated that the transgenic P. graveolens exhibited a remarkable increase in plant height (~20–23%), total biomass (18–60%), leaf: stem ratio (12–21%) and quantity of oil, compared to its wild-type counterpart. Transgenic P. graveolens expressing ACC deaminase gene from Achromobacter xylosoxidans, encoding 1-aminocyclopropane-1-carboxylilate under the control of 35 S CaMV promoter showed immense tolerance to salinity and drought stress than the wild-type plant. Parameters examined were chlorophyll content, photosynthetic parameters, relative water content (RWC), ROS production, antioxidants, proline, ACC content and real time analysis of ACC synthase, ACC deaminase, and ACC oxidase genes. The ACC deaminase-expressing transgenic lines viz. L1, L5 and L7 demonstrate a decrease of ACC content under salt and drought stress, which could lead increased ethylene production, which in turn may affect salt and drought stress. Transgenic P. graveolens showed enhanced tolerance to salt and drought stress as reflected as a result of higher leaf RWC, chlorophyll content, photosynthetic parameter, accumulation of proline and more antioxidant activity. The reported transgenic P. graveolens lines are potentially valuable materials for cultivation in saline and drought-prone areas. In this manuscript we are reporting successful production of transgenic P. graveolens with acc deaminase gene of bacterial origin. The transgenic plant has shown increase in biomass, high leaf: stem ratio, enhanced tolerance to salt and drought stress with better economic yield.

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.

A cluster of Achromobacter xylosoxidans, an emerging multidrug-resistant aquaphilic bacterium, was identified in 3 long-term-care facility residents. As Pseudomonas aeruginosa and Serratia marcescens were also present in clinical specimens, we conducted an investigation of all 3 water-associated species and identified P. aerguniosa and S. marcescens contamination at the facility. Sequencing analysis linked P. aeruginosa to a clinical isolate. Findings highlight the need for precautionary measures to prevent transmission of water-associated multidrug-resistant bacteria in long-term-care facilities.

Introduction The objective of this study was to describe two challenging cases of intravascular foreign body infections caused by multidrug-resistant Gram-negative pathogens requiring complex antimicrobial regimens including cefiderocol and successfully treated without implant removal. Methods Clinical charts and microbiological reports of the clinical cases. Results Case 1 included a left ventricular assist device (HEARTMATE 3™Abbot®) infection due to Achromobacter xylosoxidans, while case 2 included a portal prosthesis infection due to Pseudomonas aeruginosa. As the pathogens were multidrug-resistant (MDR), both cases required antimicrobial regimens with cefiderocol; treatment was successful without implant removal. Importantly, case 1 presented a probable, drug-induced thrombocytopenia, a non-previously described side effect related to cefiderocol. Conclusion Cefiderocol may be an additional, promising drug to the available arsenal, even for challenging foreign body infections caused by MDR Gram-negative pathogens.

Aim: to evaluate the infection rate and resistance of isolated Achromobacter xylosoxidans to carbapenems in adult cystic fibrosis patients (CF). Patients and Methods: a retrospective analysis of the results of culture test and time-of-flight mass spectrometry MALDI-TOF was conducted: 685 sputum samples of 58 adult CF patients for a period of 5 years (2016–2020). To assess the sensitivity to imipenem and meropenem, the agar gradient diffusion and disk diffusion method were used. Results: the incidence of infection with A. xylosoxidans in adult CF patients for the period from 2016 to 2020 when monitoring a single sample of patients (n=24) to evaluate the occurrence of this pathogen with increasing age ranged from 16.6% in 2016–2017, increasing to 37.5% in 2018–2019, and with a further reduction to 20.8% (associated with disease fatal outcome in 3 of the 9 infected patients). There was no statistically significant dependence of the fatal outcome on infection with A. xylosoxidans. When analyzing the entire pool of patients (n=58) from 2016 to 2020, the release frequency of Pseudomonas aeruginosa remains approximately the same, varying from 63.3% to 46.5% and maintaining a numerical advantage in all follow-up periods, while the A. xylosoxidans infection ranges from 13.7% to 39.3%. In 2016–2018, 50% of isolates were sensitive to carbapenems, in 2018 — 53.8% of isolates, in 2019–2020 — the activity of obtained isolates decreased to 37.5% and 30.7%, respectively. Conclusion: despite the dynamics of indicators and the sample size, the dynamics over 5 years maintained a group-wide proportion of microbiome species dominated primarily by Pseudomonas infection and A. xylosoxidans. In our follow-up, the activity of carbapenems in relation to A. xylosoxidans has almost halved. KEYWORDS: cystic fibrosis, Burkholderia cepacia complex, Achromobacter xylosoxidans, Pseudomonas aeruginosa, lethality, antibiotic resistance, carbapenems. FOR CITATION: Makhmutova V.R., Gembitskaya T.E., Chermensky A.G. et al. Achromobacter xylosoxidans infection and resistance monitoring in adult cystic fibrosis patients. Russian Medical Inquiry. 2021;5(7):462–467 (in Russ.). DOI: 10.32364/2587-6821-2021-5-7-462-467.

Tuberculosis is an airborne disease caused by Mycobacterium tuberculosis. In 15–20% cases of active disease extrapulmonary tuberculosis may occur, most commonly in the head and neck region. Tuberculous otitis media accounts for 0,1% of the total number of tuberculosis patients. This paper provides insight into current state of literature of tuberculous otitis media. It also includes the case of a 53-year-old patient with tuberculous otitis media. The patient had a liver transplantation and she showed an atypical manifestation of the disease including acute otitis media and coinfection with Achromobacter xylosoxidans. The paper describes in detail the methods of diagnosis and the infection treatment. Considering the polymorphic clinical presentation of tuberculous otitis media in cases with long lasting otorrhoea differential diagnosis should include an infection with Mycobacerium tuberculosis.

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.

In this study, 246 bacterial strains were isolated from 23 healthy plant samples were taken from different provinces. Bacterial strains were tested for hypersensitive response (HR) on tobacco. HR test showed that bacterial strains were not pathogenic. The strains were identified by using the Microbial Identification System. According to the fatty acid methyl ester analysis results bacterial strains were determined as follow; Arthbacter (17), Brevibacillus (12), Bacillus (65), Lysinibacillus (3), Herbaspirillum (7), Kocuria (21), Paucimonas (8), Pseudomonas (36), Virgibacillus (3), Microbacterium (11), Micrococcus (8), Erwinia (4), Stenotrophomonas (8), Nesterenkonia (1), Achromobacter (1), Curtobacterium (5), Rhodococcus (7), Enterobacter (2), Escherichia (1), Chryseobacterium (1), Xanthomonas (3), Acinetobacter (5), Rothia (1), Paenibacillus (1), Ochrobacterium (1), Pantoea (1), Sphingbacterium (5), Rhizobium (3), Grimontia (1), Aeromonas (1) , Brevundimonas (1), Phyllobacterium (1) ve Staphylococcus (1). The obtained bacterial strains were tested for nitrogen fixing, phosphate, potassium and calcium solubilising properties. Herbaspirillum huttiense (SK4, SK49), Microbacterium esteraromaticum (SK19, SK39, SY48), Achromobacter xylosoxidans (SK50), Paucimonas lemoignei (SK56), Pantoea agglomerans (SY43) , Pseudomonas putida biotype B (YS2, DT17), Pseudomonas syringae pv. syringae (EP19) and Pseudomonas pseudoalcaligenes (SA20) strains were found to be positive in all tests and the test results of other strains were found to be variable., Bu çalışmada, farklı illerden alınan 23 sağlıklı bitki örneğinden yapılan izolasyon sonucunda 246 bakteri straini elde edilmiştir. Tütünde yapılan HR testi ile bakteri strainlerinin patojen olmadıkları belirlenmiştir. Strainler Mikrobial Tanı Sistemi kullanılarak yağ asit metil analizi ile Arthbacter (17), Brevibacillus (12), Bacillus (65), Lysinibacillus (3), Herbaspirillum (7), Kocuria (21), Paucimonas (8), Pseudomonas (36) , Virgibacillus (3), Microbacterium (11), Micrococcus (8), Erwinia (4), Stenotrophomonas (8), Nesterenkonia (1), Achromobacter (1), Curtobacterium (5), Rhodococcus (7), Enterobacter (2), Escherichia (1), Chryseobacterium (1), Xanthomonas (3), Acinetobacter (5), Rothia (1), Paenibacillus (1), Ochrobacterium (1), Pantoea (1), Sphingbacterium (5), Rhizobium (3), Grimontia (1), Aeromonas (1), Brevundimonas (1), Phyllobacterium (1) ve Staphylococcus (1) olarak belirlenmiştir. Elde edilen bakteri strainleri azot fiksasyonu, fosfat, potasyum ve kalsiyum çözücü özellikleri bakımından test edilmiştir. Bunlar arasında Herbaspirillum huttiense (SK4, SK49), Microbacterium esteraromaticum (SK19, SK39, SY48), Achromobacter xylosoxidans (SK50), Paucimonas lemoignei (SK56), Pantoea agglomerans (SY43), Pseudomonas putida biotype B (YS2, DT17), Pseudomonas syringae pv. syringae (EP19) ve Pseudomonas pseudoalcaligenes (SA20) olmak üzere 12 tane strainin bütün testlerde pozitif sonuç verdiği, diğer strainlerin test sonuçlarının ise değişkenlik gösterdiği belirlenmiştir.

A novel strain KS-M25T was isolated from estuary water in South Korea. Strain KS-M25T was Gram-staining-negative, strictly aerobic, motile rods-shaped bacterium and showed oxidase- and catalase-positive reactions. Growth of strain KS-M25T was observed at 10–25 °C (optimum, 20 °C), at pH 5.5–9.0 (optimum, pH 7.5), and with 0–6.0% (w/v) NaCl (optimum, 1%). Ubiquinone-8 was identified as the sole isoprenoid quinone and the major fatty acids were C16:0, cyclo–C17:0 and sum in feature 3 (comprising C16:1 ω7c and/or C16:1 ω6c). The G+C content values based on genome sequences was 62.3 mol%. Phylogenetic analysis based on 16S rRNA gene sequences showed that strain KS-M25T formed a clear cluster within the genus Achromobacter. Strain KS-M25T was most closely related to Achromobacter anxifer LMG 26857T, Achromobacter dolens LMG 26840T, and Achromobacter xylosoxidans NBRC 15126T with 97.8%, 97.8%, and 97.7% 16S rRNA gene sequence similarities, respectively. Based on phenotypic, chemotaxonomic, and phylogenetic analysis, strain KS-M25T represents a novel species of the genes Achromobacter, for which the name Achromobacter aestuarii sp. nov. is proposed. The type strain is KS-M25T (= KACC 21219T = JCM 33329T).

During the study, we determined the antimicrobial activity of different selected essential oils (thyme, lemongrass, juniper, oregano, sage, fennel, rosemary, mint, rosehips, dill) on some pathogenic and spoilage bacteria isolated from the surface of various fresh vegetables. At the same time, in the case of some volatile oil combinations we followed the phenomena of synergism and antagonism. The identification of the isolated bacterial strains was made using 16S rDNA gene sequence analysis. The most resistant isolates appeared to be Curtobacterium herbarum, Achromobacter xylosoxidans, and Enterobacter ludwigii, while Pseudomonas hibiscicola was the most sensitive. Of the chosen plant essential oils, the most pronounced antimicrobial effect was detected in the case of oregano. The essential oils of thyme and mint also showed elevated antimicrobial activity. A synergistic effect was observed in case of five combinations of essential oil. Based on the results, we find that some individual essential oils and mixture compositions (due to synergic effect) could be good candidates for the preservation of fresh vegetables. These preliminary findings suggest that essential oils from locally grown spices could contribute to decreasing the health risk and also to the suppression of emergence of antibiotic resistance., Is very useful to know the pathogenic strains occurrence in different geographic regions, to prevent disease occurrence in population and among the tourists, how are more susceptible to foodborne pathogens. The main goal was the detection of active antimicrobial essential oil compositions that will be used as ingredients in active packaging materials for fresh vegetables and fruits, for decreasing the health risk and increasing the product shelf‐life.

Objectives Achromobacter xylosoxidans is an emerging pathogen in cystic fibrosis (CF). Relatively little is known about its clinical impact and optimal management. In the present study, the in vitro bactericidal activities of meropenem, either alone or in combination with colistin, levofloxacin, or chloramphenicol, were assessed using A. xylosoxidans strains isolated from CF patients. The synergistic interactions of these combinations were also investigated. Methods Minimal inhibitory concentrations (MICs) were determined by microbroth dilution. Bactericidal and synergistic effects of the tested antibiotic combinations were assessed by using the time-kill curve technique. Results Based on the time-kill curves, we found that meropenem-colistin combinations have bactericidal and synergistic activities for 24 h against A. xylosoxidans strains, both at 1 × MIC and 4 × MIC. Although synergistic interactions were seen with meropenem-levofloxacin combinations, no bactericidal interactions were observed. Additionally, the meropenem-chloramphenicol combinations were found to be neither bactericidal nor synergistic. No antagonism was observed with any combination tested. Conclusions This study’s findings could have important implications for empirical or combination antimicrobial therapy with tested antibiotics.

Cold stress in Ocimum sanctum is a major constraint to crop productivity in certain geographical regions. The current study was carried out to examine the effect of consortia of ACC deaminase producing microbes in reducing cold-induced damage in O. sanctum during winters to enable farmers to have O. sanctum as multi-cut crop. The effect of single and combined inoculation of ACC-deaminase producing four plant growth promoting bacteria (PGPB) including Brevibacterium halotolerans (Sd-6), Bacillus subtilis (Ldr-2), Achromobacter xylosoxidans (Fd-2) and Burkholderia cepacia (Art-7), and a biocontrol agent Trichoderma harzianum (Th) have been investigated. Inoculation of O. sanctum plant with Th+Fd-2 showed better photosynthetic efficiency, which could have resulted in enhanced fresh herb weight (83.78%), compared to un-inoculated control plants. Moreover, the inoculation of Th +Fd-2 improved the nutrient uptake, increased the accumulation of proline, starch, total phenolics, and reduced the accumulation of ACC (1-aminocyclopropane-1-carboxylic acid), a direct precursor for ethylene biosynthesis. Scanning electron microscopy showed the effective co-colonization of Th with Fd-2 on the root surface. Our results suggest that co-inoculation of Th+Fd-2 could be a green initiative that can improve plant growth and alleviate cold stress-induced damages in O. sanctum.

The CO2 fixation by autotrophic microbes has an important significance for improving carbon sequestration in composting. In this work, the succession of autotrophic CO2-fixing bacterial communities was investigated using quantitative PCR and high-throughput sequencing of the ribulose-1,5-bisphosphate carboxylase/oxygenase genes (cbbL and cbbM). The results presented that the number of autotrophic CO2-fixing bacteria was comparable to that in the soil, and most species have not been classified into known bacterial groups, only part of them was assigned into Proteobacteria and Actinobacteria. Phylogenetic analysis displayed that the dominant known cbbL-containing bacteria were Allochromatium vinosum, Rhodobacter sphaeroides, Nitrobacter winogradskyi, Paracoccus yeei and Porphyrobacter sp. CACIAM 03H1, while the dominant known cbbM-containing bacteria were Sulfuritalea hydrogenivorans, Pseudomonas resinovorans, Achromobacter xylosoxidans, Sphingopyxis macrogoltabida and Thermomonospora curvata. In addition, canonical correspondence analysis showed that the evolution of autotrophic CO2-fixing bacterial communities was greatly affected by physico-chemical parameters such as temperature, C/N and pH.

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.

A 78-year-old Japanese man, undergoing maintenance hemodialysis for 20 years and having received coronary artery bypass grafting two months before, was hospitalized because of fever with subclinical left-sided pleurisy. Achromobacter xylosoxidans strains exhibiting identical genomic patterns on a macrorestriction analysis were isolated from the blood and the pleural effusion obtained on admission. Physical and radiological examinations did not reveal any lesions in either chest wall or lung adjacent to the effusion, indicating that the organism in the effusion had entered the pleural space via the bloodstream. Immunocompromising conditions due to undergoing maintenance hemodialysis and the presence of the antecedently accumulated pleural effusion may have been associated with the development of hematogenous dissemination. The patient fully recovered only with antibiotic therapy. To our knowledge, the present report is the first describing a case of hematogenous pleural infection caused by A. xylosoxidans.

Significance Scleral lenses have become an increasingly common treatment for ocular surface disease and irregular corneas. Multidose, preservative-free saline solutions are frequently used off-label to fill scleral lenses. Because the fluid resides over the ocular surface during lens wear, contaminated solutions may increase the risk of infectious complications. Purpose We sought to assess the viability of skin microorganisms and pathogens associated with keratitis once introduced into a multidose preservative-free saline (MDPFS) solution containing the bacteriostatic agent boric acid (PuriLens Plus; The Lifestyle Co., Inc., Freehold, NJ). Methods Eleven bacterial and one yeast isolate were each inoculated to three lots of MDPFS as well as to sterile normal saline for comparison. Microorganism concentrations were enumerated at baseline and days 1, 3, 7, 14, 21, and 28. Persistence of microorganism viability was compared between MDPFS lots and between MDPFS and normal saline for each organism. Results Duration of microorganism viability was ≥24 hours in MDPFS with no significant difference in the distribution of survival duration of microorganisms in MDPFS versus normal saline (P = .15). Candida albicans concentrations declined 14 days earlier in MDPFS, whereas concentrations of viable organisms in MDPFS remained within 1 log of baseline for the longest durations for Pseudomonas aeruginosa (7 days), Escherichia coli (14 days), and Achromobacter xylosoxidans (≥28 days). Gram-positive organism concentrations remained within 1 log of baseline for no more than 3 days. Mild lot-to-lot variation in organism concentrations was noted near the end points of viability. Bacteriostasis was demonstrated in that concentrations of all organisms remained at or below baseline levels throughout the 28-day period. Conclusions After microbial contamination, persistence of organism viability was similar in PuriLens and normal saline. Environmental gram-negative organisms, many of which can contribute to infectious keratitis, can persist for weeks once introduced into saline solutions.

SummaryWe report a rare case of Achromobacter xylosoxidans bacteremia recurrence in non-immunecompromised old woman in 2014 and 2020. During the last 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. The patient relapsed 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 21 cases of Achromobacter xylosoxidans endocarditis that have been described in the literature.

Introduction Fungi are considered to be opportunistic pathogens that may play a significant role in the pathogenesis of endodontic infections. The main purpose of the study was to assess the prevalence of two selected genera of fungi, namely Candida albicans and Aspergillus spp. by using Real Time-Polymerace Chain Reaction (RT-PCR) and to compare the findings with the respective ones obtained by a culture-dependent approach, the Matrix-assisted laser desorption/ionization Time of Flight Mass Spectrometry (MALDI-ToF MS). A secondary aim was to assess the presence of other bacteria growing under aerobic conditions. Methods Microbial samples were obtained from root canals of 60 teeth associated with pulp necrosis and apical periodontitis. DNA was extracted and RT-PCR was applied for detection of C. albicans and Aspergillus spp. pathogenic subtypes. In addition, MALDI-ToF MS was performed to identify microorganisms grown under aerobic conditions. Results Based on RT-PCR, Aspergillus was detected in 8 cases whereas C. albicans in 4 cases. Using MALDI-ToF MS, no trace of Aspergillus was detected whereas C. albicans identified in two cases. Significant differences were revealed in the detection potential for the Aspergillus spp. between MALDI-ToF MS and RT-PCR (p=0.01); conversely, this was not the case for C. albicans (p=0.50). Following MALDI-ToF MS, 35 samples showed evidence of bacterial growth. The vast majority was colonized by Achromobacter xylosoxidans, followed by Lactobacillus spp., Methylobacterium spp. and Enterococcus faecalis. Conclusions The findings confirm the presence of fungi in primarily infected canals with apical periodontitis as well as of some rarely inspected aerobic bacterial species. A. xylosoxidans was prevalent, while the clinical relevance of its presence is deemed to be further investigated.

Achromobacter xylosoxidans (A. xylosoxidans) is an aerobic gram-negative bacillus and often isolated from aquatic environments. It is supposed to cause infections in patients with malignancy or immunodeficiency. It causes various healthcare-associated infections, but cellulitis is rare. Herein, we report the first case of sever cellulitis by A. xylosoxidans after allogeneic hematopoietic stem cell transplantation (HSCT). A 49-year-old man underwent allogeneic HSCT from 8/8 HLA-matched unrelated donor with myeloablative conditioning for relapsed acute myeloid leukemia. He developed skin chronic graft versus host disease 11 months after HSCT. During the prolonged treatment with prednisolone and cyclosporine, he developed cellulitis on his left leg and admitted to our hospital. Blood and exudate culture revealed A. xylosoxidans. Although empirical therapy with cefepime was ineffective, his symptoms were dramatically improved after administration of meropenem. To our knowledge, this is the first case of A. xylosoxidans cellulitis after allogeneic HSCT. A. xylosoxidans should be considered as a possible cause of cellulitis in post-allogeneic HSCT patients on prolonged immunosuppressive therapy.

Atypical microbial keratitis refers to corneal infections caused by micro-organisms not commonly encountered in clinical practice. Unlike infections caused by common bacteria, cases of atypical microbial keratitis are often associated with worse clinical outcomes and visual prognosis. This is due to the challenges in the identification of causative organisms with standard diagnostic techniques, resulting in delays in the initiation of appropriate therapies. Furthermore, due to the comparatively lower incidence of atypical microbial keratitis, there is limited literature on effective management strategies for some of these difficult to manage corneal infections. This review highlights the current management and available evidence of atypical microbial keratitis, focusing on atypical mycobacteria keratitis, nocardia keratitis, achromobacter keratitis, and pythium keratitis. It will also describe the management of two uncommonly encountered conditions, infectious crystalline keratopathy and post-refractive infectious keratitis. This review can be used as a guide for clinicians managing patients with such challenging corneal infections.

After a cholecystectomy, dropped stones can serve as a nidus for abscess formation. Intrabdominal abscesses tend to cause irritation and inflammation of the peritoneum and are thus rarely asymptomatic. This report discusses a 38-year-old female complaining of a recurrent right upper quadrant pain that led to multiple hospital admissions. Her surgical history was significant for cholecystectomy six years back complicated by a retroperitoneal abscess which was drained twice. A computed tomography (CT) scan was done, and she was diagnosed with a subdiaphragmatic collection as a result of a dropped stone.

Cystic fibrosis (CF) is a genetic disorder causing dysfunctional ion transport resulting in accumulation of viscous mucus that fosters chronic bacterial biofilm-associated infection in the airways. Achromobacter xylosoxidans and Stenotrophomonas maltophilia are increasingly prevalent CF pathogens and while Burkholderia cencocepacia is slowly decreasing, all are complicated by multidrug resistance that is enhanced by biofilm formation. This study investigates potential synergy between the antibiotics ciprofloxacin (0.5–128 µg/mL), colistin (0.5–128 µg/mL) and tobramycin (0.5–128 µg/mL) when combined with the neutral pH form of N-Acetylcysteine (NACneutral) (0.5–16.3 mg/mL) against 11 cystic fibrosis strains of Burkholderia, Stenotrophomonas and Achromobacter sp. in planktonic and biofilm cultures. We screened for potential synergism using checkerboard assays from which fraction inhibitory concentration indices (FICI) were calculated. Synergistic (FICI ≤ 0.5) and additive (0.5 &gt, FICI ≥ 1) combinations were tested on irreversibly attached bacteria and 48 h mature biofilms via time-course and colony forming units (CFU/mL) assays. This study suggests that planktonic FICI analysis does not necessarily translate to reduction in bacterial loads in a biofilm model. Future directions include refining synergy testing and determining further mechanisms of action of NAC to understand how it may interact with antibiotics to better predict synergy.

Aims: To assess the prevalence of A. xylosoxidans isolated from non-respiratory tract samples from adult inpatients and outpatients and the antibiotic resistance levels at a tertiary-care teaching hospital in Szeged, Hungary retrospectively, during a 10-year study period. Study Design: Retrospective microbiological study. Place and Duration of Study: 1st of January 2008 - 31st of December 2017 at the University of Szeged, which is affiliated with the Albert Szent-Györgyi Clinical Center, a primary- and tertiary-care teaching hospital in the Southern Great Plain of Hungary. Methodology: Data collection was performed electronically. Antimicrobial susceptibility testing (AST) was performed using disk diffusion method and when appropriate, E-tests on Mueller–Hinton agar plates. Results: During the 10-year study period, a total of 68 individual A. xylosoxidans isolates were identified (6.8±3.6/year, range: 0-11 isolates). The frequency of isolation in the first half of the study period (2008-2017) was n=22, while in 2013-2017, this number was n=46. The majority of isolates (51 out of 68) were from inpatient departments. 32 out of 68 patients were female (female-to-male ratio: 0.89). The susceptibilities of the respective A. xylosoxidans isolates (n=68) were the following: high levels of susceptibility for imipenem and meropenem (n=63; 92.6%), and moxifloxacin (n=55; 80.9%), while higher rates of resistance were detected for sulfamethoxazole/trimethoprim (susceptible: n=36; 52.9%), ciprofloxacin (susceptible: n=40; 58.8%) and almost all isolates were resistant to ceftazidime (susceptible: n=3; 4.4%) and cefepime (n=2; 2.9%). Conclusion: The existing literature on Achromobacter infections in the context of non-respiratory human infections is scarce, as the incidence of these pathogens in clinically-relevant syndromes in low. The developments in diagnostic technologies in routine clinical microbiology will probably lead to a shift in the isolation frequency of these bacteria in the future.

Corneal infection is a devastating sight-threatening complication that is associated with contact lens (CL) wear, commonly caused by Pseudomonas aeruginosa. Lately, Achromobacter xylosoxidans, Delf...

Azithromycin (AZM), the most commonly prescribed antibiotic in the United States, is thought to have no activity against multidrug-resistant Gram-negative pathogens such as Achromobacter xylosoxidans (AX) per standard minimum inhibitory concentration testing in cation-adjusted Mueller Hinton Broth. Here we provide the first report of AZM bactericidal activity against carbapenem-resistant isolates of AX, with a multifold decrease in minimum inhibitory concentration across 12 clinical isolates when examined under physiologic testing conditions that better recapitulate the in vivo human environment. This pharmaceutical activity, evident in eukaryotic tissue culture media, is associated with enhanced AZM intracellular penetration and synergistic killing with human whole blood, serum, and neutrophils. Additionally, AZM monotherapy inhibited preformed AX biofilm growth in a dose-dependent manner together with a reduction in viable bacteria. In an illustrative case, AZM in combination with piperacillin-tazobactam exerted clear therapeutic effects in a patient with carbapenem-resistant AX mediastinitis, sternal osteomyelitis, and aortic graft infection. Our study reinforces how current antimicrobial testing practices fail to recapitulate the host environment or host-pathogen interactions and may misleadingly declare complete resistance to useful agents, adversely affecting patient outcomes. We conclude that AZM merits further exploration in the treatment of drug-resistant AX infections. Novel approaches to antimicrobial susceptibility testing that better recapitulate the host environment should be considered, especially as infections caused by multidrug-resistant Gram-negative bacterial pathogens are expanding globally with high morbidity and mortality.

Open in a separate window In the present study, the effects of the corrosive bacterial community and the biofilm on cooling water systems made from mild steel (MS) and brass (BR) were studied under field exposure conditions using electrochemical impedance spectroscopy measurements, scanning electron microscope, and X-ray diffraction methods. Results from16S rRNA gene sequences showed that the predominant bacteria species detected in the biofilm of MS and BR metals during 360 days of exposure were Bacillus cereus EN14, Achromobacter xylosoxidans EN15, A. xylosoxidans EN16, and B. cereus EN17. The weight loss results revealed that a higher corrosion rate was observed in MS (0.7 ± 0.1 mm/y) compared with that in BR (0.17 ± 0.05 mm/y) at the end of the exposure period. This can be explained by the bacterial communities enhancing the corrosion rates by creating a local corrosive environment. Scanning electron microscope images revealed the adsorption of biofilm on the MS and BR surfaces following180 days of exposure. From the electrochemical impedance study, a higher charge transfer resistance (Rct) was obtained for BR (119.6 Ω cm2) when compared with that of MS (43.4 Ω cm2). This study explains the role of bacterial communities and their mechanisms in the corrosion of MS and BR in cooling water systems.

Chromium contamination in soil and water bodies is increasing predominantly due to inappropriate discharge from industries, and it is causing severe environmental problems and soil infertility. To improve soil quality, the sustainable approach needs to identify specific microbes capable of reducing chromium toxicity, enhancing soil P pool and expressing multiple plant growth-promoting activities. In the current investigation, a microbial strain OS2 was recuperated from polluted soil and was characterized by employing biochemical and molecular methods. Bacterial strain OS2 was identified as Achromobacter xylosoxidans by 16S rRNA quality sequencing, BLASTn, and phylogenetic examination. Strain OS2 survived well at high doses of heavy metals: Cr, Ni, Cu and Zn. A. xylosoxidans could solubilize up to 363 µg mL−1 tricalcium phosphate and reduced 100 µg mL−1 chromium after 24-h incubation. SEM and EDX analyses showed the highest accumulation of phosphate and binding with chromium up to 10.22 and 1.09 weight percent of total weight, respectively. A. xylosoxidans significantly produced IAA (26 µg mL−1) when grown up within 100 µg mL−1 chromium, as detected by HPLC. Further, strain OS2, when used as a microbial inoculant, decontaminated the chromium and concurrently improved the growth of mung bean plants while growing under metal stress conditions significantly in a sustainable manner.

International audience; Several predictive models have been proposed to understand the microbial risk factors associated with cystic fibrosis (CF) progression. Very few have integrated fungal airways colonisation, which is increasingly recognized as a key player regarding CF progression. To assess the association between the percent predicted forced expiratory volume in 1 s (ppFEV1) change and the fungi or bacteria identified in the sputum, 299 CF patients from the “MucoFong” project were included and followed-up with over two years. The relationship between the microorganisms identified in the sputum and ppFEV1 course of patients was longitudinally analysed. An adjusted linear mixed model analysis was performed to evaluate the effect of a transient or chronic bacterial and/or fungal colonisation at inclusion on the ppFEV1 change over a two-year period. Pseudomonas aeruginosa, Achromobacter xylosoxidans, Stenotrophomonas maltophilia, and Candida albicans were associated with a significant ppFEV1 decrease. No significant association was found with other fungal colonisations. In addition, the ppFEV1 outcome in our model was 11.26% lower in patients presenting with a transient colonisation with non-pneumoniae Streptococcus species compared to other patients. These results confirm recently published data and provide new insights into bacterial and fungal colonisation as key factors for the assessment of lung function decline in CF patients.

Achromobacter species are increasingly being detected in cystic fibrosis (CF) patients, where they can establish chronic infections by adapting to the lower airway environment. To better understand the mechanisms contributing to a successful colonization by Achromobacter species, we sequenced the whole genome of 54 isolates from 26 patients with occasional and early/late chronic lung infection. We performed a phylogenetic analysis and compared virulence and resistance genes, genetic variants and mutations, and hypermutability mechanisms between chronic and occasional isolates. We identified five Achromobacter species as well as two non-affiliated genogroups (NGs). Among them were the frequently isolated Achromobacter xylosoxidans and four other species whose clinical importance is not yet clear: Achromobacter insuavis, Achromobacter dolens, Achromobacter insolitus and Achromobacter aegrifaciens . While A. insuavis and A. dolens were isolated only from chronically infected patients and A. aegrifaciens only from occasionally infected patients, the other species were found in both groups. Most of the occasional isolates lacked functional genes involved in invasiveness, chemotaxis, type 3 secretion system and anaerobic growth, whereas the great majority (>60%) of chronic isolates had these genomic features. Interestingly, almost all (n=22/23) late chronic isolates lacked functional genes involved in lipopolysaccharide production. Regarding antibiotic resistance, we observed a species-specific distribution of blaOXA genes, confirming what has been reported in the literature and additionally identifying blaOXA-2 in some A. insolitus isolates and observing no blaOXA genes in A. aegrifaciens or NGs. No significant difference in resistance genes was found between chronic and occasional isolates. The results of the mutator genes analysis showed that no occasional isolate had hypermutator characteristics, while 60% of early chronic (1 year from first colonization) isolates were classified as hypermutators. Although all A. dolens, A. insuavis and NG isolates presented two different mutS genes, these seem to have a complementary rather than compensatory function. In conclusion, our results show that Achromobacter species can exhibit different adaptive mechanisms and some of these mechanisms might be more useful than others in establishing a chronic infection in CF patients, highlighting their importance for the clinical setting and the need for further studies on the less clinically characterized Achromobacter species.

Non-Hodgkin B-cell lymphomas (NHL) are a heterogeneous group of lymphoid neoplasms with complex etiopathology, rich symptomatology, and a variety of clinical courses, therefore requiring different therapeutic approaches. The hypothesis that an infectious agent may initiate chronic inflammation and facilitate B lymphocyte transformation and lymphogenesis has been raised in recent years. Viruses, like EBV, HTLV-1, HIV, HCV and parasites, like Plasmodium falciparum, have been linked to the development of lymphomas. The association of chronic Helicobacter pylori (H. pylori) infection with mucosa-associated lymphoid tissue (MALT) lymphoma, Borrelia burgdorferi with cutaneous MALT lymphoma and Chlamydophila psittaci with ocular adnexal MALT lymphoma is well documented. Recent studies have indicated that other infectious agents may also be relevant in B-cell lymphogenesis such as Coxiella burnettii, Campylobacter jejuni, Achromobacter xylosoxidans, and Escherichia coli. The aim of the present review is to provide a summary of the current literature on infectious bacterial agents associated with B-cell NHL and to discuss its role in lymphogenesis, taking into account the interaction between infectious agents, host factors, and the tumor environment.

Achromobacter xylosoxidans(AX), also called alcaligenes xylosoxidans, is an aerobic, non-fermenting mobile, gram-negative bacillus which was first isolated in an otorrhea samples in 1971. Infections with these species are quite rare and have often been described in immunocompromised and in premature infants. However, very few cases of meningitis related to AX have been reported in the literature. The authors report a new case of meningitis due to AX in a 45-day-old female infant with polymarformative syndrome meningitis was confirmed by a cyto-biochemical analysis and culture of the cerebrospinal fluid and was treated by antibiotherapy. Hydrocephalus was managed initially with external ventricular drainage followed by a ventriculoperitoneal shunt after rigorous cerebrospinal fluid (CSF) sterilization, with good clinical and radiological outcomes. The prompt and adequate antibiotic adjustment following bacterial isolation has been shown to rapidly modify the clinical outcomes.

Achromobacter xylosoxidans,subspecies denitrificans is a rare Gram-negative bacillus that causes health care associated infections in immunocompromised hosts. Carbapenems and anti-pseudomonal penicillins are listed as suitable empiric therapy in the literature. Herein, we report a case of a 77-year-old male with stage IV adenocarcinoma of the lung who presented with and was improving from Salmonella javiana enterocolitis, only to subsequently develop A. xylosoxidans,subspecies denitrificans bacteremia that was resistant to both meropenem and piperacillin-tazobactam. With empiric antibiotic coverage falling short of microbial clearance, timelyin vitrosusceptibility testing and prompt infectious disease consultation are of the utmost importance for treatment.

Background Achromobacter xylosoxidans is an opportunistic environmental aerobe. In cases where A. xylosoxidans infects humans, it most commonly manifests as bacteraemia in the immunosuppressed. A. xylosoxidans causing chronic osteomyelitis is rare, particularly in the immunocompetent and young. Case We present the case of a 23-year-old man with chronic osteomyelitis of the right femur caused by co-infection of A. xylosoxidans and Staphylococcus aureus. Five years earlier, he had sustained a right femur fracture and was treated with intramedullary fixation at a peripheral hospital in a developing nation. Past medical history was otherwise unremarkable. Management comprised of surgical debridement and culture-directed antibiotic therapy, resulting in clinical cure. Conclusion In the context of local trauma and previous surgery, osteomyelitis caused by atypical pathogens must be considered. A multidisciplinary approach commensurate with duration and severity of infection and tailored to the causative organism is paramount.

Background Despite the increasing prevalence of Achromobacter xylosoxidans lung infection in patients with cystic fibrosis (CF), its clinical pathogenicity remains controversial. The objective of this study was to evaluate the effects of this emerging bacterium on lung disease severity in CF children. Methods This case–control retrospective study took place in two French paediatric CF centres. 45 cases infected by A. xylosoxidans were matched for age, sex, CFTR genotypes and pancreatic status to 45 never-infected controls. Clinical data were retrieved from clinical records over the 2 years before and after A. xylosoxidans initial infection. Results At infection onset, lung function was lower in cases compared with controls (p=0.006). Over the 2 years prior to A. xylosoxidans acquisition, compared with controls, cases had more frequent pulmonary exacerbations (p=0.02), hospitalisations (p=0.05), and intravenous (p=0.03) and oral (p=0.001) antibiotic courses. In the 2 years following A. xylosoxidans infection, cases remained more severe with more frequent pulmonary exacerbations (p=0.0001), hospitalisations (p=0.0001), and intravenous (p=0.0001) and oral antibiotic courses (p=0.0001). Lung function decline tended to be faster in cases (−5.5% per year) compared with controls (−0.5% per year). Conclusions This case–control study demonstrates that A. xylosoxidans occurs more frequently in the patients with the worse lung disease. Further studies assessing the pathogenicity of this emerging pathogen and international treatment recommendations are warranted., The prevalence of the opportunistic pathogen Achromobacter xylosoxidans increases in patients with CF. This study shows an association between airway infection with this bacterium and more severe lung disease in children with CF. https://bit.ly/3a7ioSi

In response to environmental and health concerns about the extended use of pesticides, it exists a considerable interest in finding alternative control approaches. The current study compared the antifungal activities of some biocontrol agents. Three fungal strains were isolated from infected tomato. Two belonged to genus Aspergillus and the third was Fusarium sp. Ten morphologically different bacterial strains were isolated from intact tomato roots and rhizospheric soils, they were screened for their antagonistic effects against the fungal isolates. Achromobacter xylosoxidans produced the most potent antifungal activity as indicated by the percentage of fungal weight loss recorded (equivalent to 73, 77, and 99% for Aspergillus sp. 1, Fusarium sp., and Aspergillus sp. 2, respectively). Four tested plants: Inula (Dittrichia viscosa), Onion (Allium cepa), Basillic (Ocimum basilicum), and Quinoa (Chenopodium quinoa) were evaluated for their antifungal activities against the isolated fungal pathogens. Inula extract exhibited the highest inhibition of fungal growth among the tested plants. The MIC values were evaluated for the tested biocontrol agents and compared with the standard antifungal chemicals: Between and Logico. In vivo study was performed. using seedlings of Tomato (Solanum lycopersicum). The seedlings infected with the fungal pathogens using spraying technique showed severe symptoms of fungal disease, while the tomato seedlings infected with fungal pathogens and treated with the biocontrol agents (cell-free supernatant of A. xylosoxidans or Inula extract) exhibited observed reduction in the percentage of disease severity.

Arsenotrophic bacteria play an essential role in lowering arsenic contamination by converting toxic arsenite [As (III)] to less toxic and less bio-accumulative arsenate [As (V)]. The current study focused on the qualitative and electrocatalytic detection of the arsenite oxidation potential of an arsenite-oxidizing bacteria A. xylosoxidans BHW-15 (retrieved from As-contaminated tube well water), which could significantly contribute to arsenic detoxification, accumulation, and immobilization while also providing a scientific foundation for future electrochemical sensor development. The minimum inhibitory concentration (MIC) value for the bacteria was 15 mM As (III). Scanning Electron Microscopy (SEM) investigation validated its intracellular As uptake capacity and demonstrated a substantial association with the MIC value. During the stationary phase, the strain’s As (III) transformation efficiency was 0.0224 mM/h. Molecular analysis by real-time qPCR showed arsenite oxidase (aioA) gene expression increased 1.6-fold in the presence of As (III) compared to the untreated cells. The immobilized whole-cell also showed As (III) conversion up to 18 days. To analyze the electrochemical oxidation in water, we developed a modified GCE/P-Arg/ErGO-AuNPs electrode, which successfully sensed and quantified conversion of As (III) into As (V) by accepting electrons; implying a functional As oxidase enzyme activity in the cells. To the best of our knowledge, this is the first report on the electrochemical observation of the As-transformation mechanism with Achromobactersp. Furthermore, the current work highlighted that our isolate might be employed as a promising candidate for arsenic bioremediation, and information acquired from this study may be helpful to open a new window for the development of a cost-effective, eco-friendly biosensor for arsenic species detection in the future.

In patients with cystic fibrosis (CF), the lung is a remarkable ecological niche in which the microbiome is subjected to important selective pressures. An inexorable colonization by bacteria of both endogenous and environmental origin is observed in most patients, leading to a vicious cycle of infection–inflammation. In this context, long-term colonization together with competitive interactions among bacteria can lead to over-inflammation. While Pseudomonas aeruginosa and Staphylococcus aureus, the two pathogens most frequently identified in CF, have been largely studied for adaptation to the CF lung, in the last few years, there has been a growing interest in emerging pathogens of environmental origin, namely Achromobacter xylosoxidans and Stenotrophomonas maltophilia. The aim of this review is to gather all the current knowledge on the major pathophysiological traits, their supporting mechanisms, regulation and evolutionary modifications involved in colonization, virulence, and competitive interactions with other members of the lung microbiota for these emerging pathogens, with all these mechanisms being major drivers of persistence in the CF lung. Currently available research on A. xylosoxidans complex and S. maltophilia shows that these emerging pathogens share important pathophysiological features with well-known CF pathogens, making them important members of the complex bacterial community living in the CF lung.

Good’s syndrome is a rare, adult-onset immunodeficiency syndrome associated with thymomas. Here, we present a 71-year-old, previously healthy male with a history of opportunistic infections status post-thymectomy, who presented with a septic knee complicated with bacteremia without any inciting factor. Therefore, a diagnosis of Good syndrome was made. While this is a rare disease, clinicians should have a high suspicion in patients with a history of thymoma. Early diagnosis and treatment can reduce opportunistic infections and improve morbidity and mortality.

Background While Pseudomonas aeruginosa (Pa) eradication regimens have contributed to a decline in Pa prevalence in people with cystic fibrosis (CF), this antibiotic exposure might increase the risk of acquisition of drug-resistant organisms. This study evaluated the association between antipseudomonal antibiotic exposure intensity and acquisition risk of drug-resistant organisms among children with CF and new Pa infection. Methods We utilized data from the Early Pseudomonas Infection Control Clinical Trial (EPIC CT), a randomized controlled trial comparing Pa eradication strategies in children with CF and new Pa. The exposure was the number of weeks of oral or inhaled antipseudomonal antibiotics or ever versus never treatment with intravenous antipseudomonal antibiotics during the 18 months of EPIC CT participation. Primary outcomes were risks of acquisition of several respiratory organisms during 5 years of follow-up after EPIC CT estimated using Cox proportional hazards models separately for each specific organism. Results Among 249 participants, there was no increased acquisition risk of any organism associated with greater inhaled antibiotic exposure. With each additional week of oral antibiotics, there was an increased hazard of Achromobacter xylosoxidans acquisition (HR, 1.24; 95% CI: 1.02–1.50; P = .03). Treatment with intravenous antibiotics was associated with an increased hazard of acquisition of multidrug-resistant Pa (HR, 2.47; 95% CI: 1.28–4.78; P = .01) and MRSA (HR, 1.57; 95% CI: 1.03–2.40; P = .04). Conclusions Results from this study illustrate the importance of making careful antibiotic choices to balance the benefits of antibiotics in people with CF while minimizing risk of acquisition of drug-resistant organisms.

Aims: The genus Achromobacter includes lactose-non-fermenting Gram-negative bacteria that are aerobic, motile (with peritrichous flagella), oxidase and catalase-positive. To assess the prevalence of A. xylosoxidans isolated from non-respiratory tract samples from adult inpatients and outpatients and the antibiotic resistance levels at a tertiary-care teaching hospital in Szeged, Hungary retrospectively, during a 10-year study period. Study Design: Retrospective microbiological study. Place and Duration of Study: 1st of January 2008 - 31st of December 2017 at the University of Szeged, which is affiliated with the Albert Szent-Gyorgyi Clinical Center, a primary- and tertiary-care teaching hospital in the Southern Great Plain of Hungary. Methodology: Data collection was performed electronically. Antimicrobial susceptibility testing (AST) was performed using disk diffusion method and when appropriate, E-tests on Mueller–Hinton agar plates. Results: During the 10-year study period, a total of 68 individual A. xylosoxidans isolates were identified (6.8±3.6/year, range: 0-11 isolates). The frequency of isolation in the first half of the study period (2008-2017) was n=22, while in 2013-2017, this number was n=46. The majority of isolates (51 out of 68) were from inpatient departments. 32 out of 68 patients were female (female-to-male ratio: 0.89). The susceptibilities of the respective A. xylosoxidans isolates (n=68) were the following: high levels of susceptibility for imipenem and meropenem (n=63; 92.6%), and moxifloxacin (n=55; 80.9%), while higher rates of resistance were detected for sulfamethoxazole/trimethoprim (susceptible: n=36; 52.9%), ciprofloxacin (susceptible: n=40; 58.8%) and almost all isolates were resistant to ceftazidime (susceptible: n=3; 4.4%) and cefepime (n=2; 2.9%). Conclusion: The existing literature on Achromobacter infections in the context of non-respiratory human infections is scarce, as the incidence of these pathogens in clinically-relevant syndromes in low. It should be noted, that the difficulty in the adequate identification (especially in low-resource settings) may be partly blamed for the infrequent characterization of these bacteria as significant pathogens. The developments in diagnostic technologies in routine clinical microbiology will probably lead to a shift in the isolation frequency of these bacteria in the future.

Mucosa-associated lymphoid tissue (MALT) lymphoma is generally associated with chronic antigen stimulation: auto-antigens or of microbial origin. Only one study suggested association between Achromobacter xylosoxidans and pulmonary MALT lymphoma. We aimed to investigate the presence of virus or any infectious agents in pulmonary MALT lymphoma by using metagenomic next-generation sequencing (mNGS).All lung samples were centrally reviewed. The t(11;18) (q21;q21) was evaluated by FISH analysis. The snap frozen large lung biopsies were analyzed by mNGS. After lung biopsies homogenization total nucleic acids (RNA and DNA) were extracted, amplified and classified according to their taxonomic assignment, after exclusion of host DNA.We included 13 samples from pulmonary MALT lymphoma (mean age: 60.3 years, 7 women, 3 with auto-immune background) and 10 controls. The diagnosis of MALT lymphoma was confirmed for the 13 samples, 3 showed API2-MALT1 translocation (23%). No evidence of the presence of a specific pathogen was clearly identified in the group of patients with pulmonary MALT lymphoma. We identifiedA. xylosoxidans sequence in 4/13 patients and in 4/10 controls.This study did not find evidence for a DNA or RNA virus, a fungi, a parasite or a bacteria associated with pulmonary MALT lymphoma either in the stroma or in tumor cells.

Achromobacter spp. are ubiquitous in nature and are increasingly being recognized as emerging nosocomial pathogens. Nevertheless, to date, only 30 complete genome sequences of Achromobacter phages are available in GenBank, and nearly all of those phages were isolated on Achromobacter xylosoxidans. Here, we report the isolation and characterization of bacteriophage vB_AchrS_AchV4. To the best of our knowledge, vB_AchrS_AchV4 is the first virus isolated from Achromobacter spanius. Both vB_AchrS_AchV4 and its host, Achromobacter spanius RL_4, were isolated in Lithuania. VB_AchrS_AchV4 is a siphovirus, since it has an isometric head (64 ± 3.2 nm in diameter) and a non-contractile flexible tail (232 ± 5.4). The genome of vB_AchrS_AchV4 is a linear dsDNA molecule of 59,489 bp with a G+C content of 62.8%. It contains no tRNA genes, yet it includes 82 protein-coding genes, of which 27 have no homologues in phages. Using bioinformatics approaches, 36 vB_AchrS_AchV4 genes were given a putative function. A further four were annotated based on the results of LC–MS/MS. Comparative analyses revealed that vB_AchrS_AchV4 is a singleton siphovirus with no close relatives among known tailed phages. In summary, this work not only describes a novel and unique phage, but also advances our knowledge of genetic diversity and evolution of Achromobacter bacteriophages.

(1) Background: Environmental contamination with antibiotics is particularly serious because the usual methods used in wastewater treatment plants turn out to be insufficient or ineffective. An interesting idea is to support natural biodegradation processes with physicochemical methods as well as with bioaugmentation with efficient microbial degraders. Hence, the aim of our study is evaluation of the effectiveness of different methods of nitrofurazone (NFZ) degradation: photolysis and photodegradation in the presence of two photocatalysts, the commercial TiO2-P25 and a self-obtained Fe3O4@SiO2/TiO2 magnetic photocatalyst. (2) Methods: The chemical nature of the photocatalysis products was investigated using a spectrometric method, and then, they were subjected to biodegradation using the strain Achromobacter xylosoxidans NFZ2. Additionally, the effects of the photodegradation products on bacterial cell surface properties and membranes were studied. (3) Results: Photocatalysis with TiO2-P25 allowed reduction of NFZ by over 90%, demonstrating that this method is twice as effective as photolysis alone. Moreover, the bacterial strain used proved to be effective in the removal of NFZ, as well as its intermediates. (4) Conclusions: The results indicated that photocatalysis alone or coupled with biodegradation with the strain A. xylosoxidans NFZ2 leads to efficient degradation and almost complete mineralization of NFZ.

Background Carbapenem resistance in Gram-negative bacteria is an ongoing public health problem of global dimensions leaving very few treatment options for infected patients. Objectives To study the dissemination of plasmid-borne carbapenemase genes in Gram-negative bacteria from a diagnostic centre in Tamil Nadu, India. Methods A total of 151 non-repetitive isolates belonging to 10 genera were collected between January 2015 and December 2016 from a diagnostic centre in Tamil Nadu. The isolates included Escherichia coli (n = 57), Klebsiella pneumoniae (n = 45), Pseudomonas aeruginosa (n = 10), Salmonella Typhi (n = 8), Enterobacter cloacae (n = 8), Acinetobacter baumannii (n = 7), Serratia marcescens (n = 5), Achromobacter xylosoxidans (n = 5), Proteus mirabilis (n = 5), Klebsiella oxytoca (n = 5) and Elizabethkingia meningoseptica (n = 1). Results Of the 151 isolates, 71% (n = 107) and 68% (n = 103) were found to be resistant to meropenem and imipenem, respectively. The most prevalent β-lactamase gene was blaNDM-1 (n = 22), followed by blaOXA-181 (n = 21), blaGES-1 (n = 11), blaOXA-51 (n = 9), blaGES-9 (n = 8), blaOXA-23 (n = 7) and blaIMP-1 (n = 3). We also observed blaOXA-23 in E. coli (n = 4), and three K. pneumoniae were positive for both, blaOXA-23 and blaOXA-51. Plasmid incompatibility (inc/rep) typing results showed that the resistance genes (n = 11) were present in the isolates carrying plasmid-types IncX, IncA/C, IncFIA-FIB and IncFIIA. The plasmid-borne resistance genes in E. coli and K. pneumoniae were transferred to susceptible E. coli AB1157. Conclusions This study highlights the prevalence of carbapenem resistance and the acquisition of plasmid-borne carbapenemase genes in Gram-negative bacteria isolated at this centre.