Non-fermenting Bacteria Research Articles

Impact of the COVID-19 Pandemic on Diabetic Foot Patients: A Shift in the Infectious Agent Profile Toward Nonfermentative Gram-Negative Bacilli.

Diabetes foot infection is a very important public health problem that causes serious health problems, mortality, and high health expenditures, and is one of the most important complications of diabetes mellitus. There are concerns that approaches such as limited personal visits to doctors, avoidance of hospitals, and restrictions on nonemergency surgical procedures during the coronavirus disease of 2019 pandemic pose a threat to those with diabetic foot problems, including diabetic foot ulcers (DFUs), ischemia, and infection, resulting in increased limb loss and mortality. This multicenter, retrospective, cross-sectional study was conducted in 14 tertiary care hospitals from various regions of Turkey. A total of 1,394 patient records were evaluated, 794 of which were between January 1, 2019, and January 30, 2020 (prepandemic [Pre-P]), and 605 of which were between February 1, 2020, and February 28, 2021 (pandemic period [PP]). During the PP, diabetic foot patient follow-up decreased by 23.8%. In addition, the number of hospitalizations attributable to DFU has decreased significantly during the PP (P = .035). There was no difference between the groups regarding patient demographics, medical history, DFU severity, biochemical and radiologic findings, or comorbidities, but the mean duration of diabetes mellitus years was longer in patients in the Pre-P than in those in the PP (15.1 years versus 13.7 years). There was no difference between the two groups in terms of major complications such as limb loss and mortality, but infection recurrence was higher in the PP than in the Pre-P (12.9% versus 11.4%; P < .05). The prevalence of nonfermentative gram-negative bacteria as causative agents in DFU infections increased during the PP. In particular, the prevalence of carbapenem-resistant Pseudomonas spp. increased statistically during the PP. The rapid adaptation to the pandemic with the measures and changes developed by the multidisciplinary diabetic foot care committees may be the reasons why there was no increase in complications because of DFU during the pandemic in Turkey.

Species diversity of non-fermenting gram-negative bacteria selected from wound drainage of patients of a multidisciplinary hospital

Species diversity of non-fermenting gram-negative bacteria selected from wound drainage of patients of a multidisciplinary hospital

Comparison of COVID-19 and Non–COVID-19 Patients in Intensive Care Unit for Secondary Infections

Background Bacterial secondary infections were commonly reported in viral respiratory tract infections. However, it is not clear whether there is a difference in the infection rates during the hospitalization in intensive care unit (ICU) caused by COVID-19. The aim of this study was to evaluate the secondary infections in long-term hospitalized patients in the ICU due to COVID-19 and whether COVID-19 increases the tendency to secondary infection in ICU patients. Methods This is a retrospective case-control study. It was conducted in a tertiary care hospital including 34-bed COVID-19 ICU and 20-bed non–COVID-19 ICU. Adult patients in the ICU hospitalized for ≥10 days were included the study. The results of microbiological cultures of blood, urine, and respiratory samples were evaluated in terms of infections during their hospitalization. Results The study group consisted of 51 patients with COVID-19 and the control group consisted of 57 non–COVID-19 patients. There was no significant difference between 2 groups in terms of distribution and frequency of agents isolated from blood culture. The frequency of isolation of Enterobacterales members in urine cultures and nonfermenting bacteria in respiratory samples were significantly higher in non–COVID-19 patients compared with COVID-19 patients (P &lt; 0.05). Conclusions This study revealed that there was no difference among the patients with and without COVID-19 in ICU for the secondary infections when the ICU stay was prolonged. We think that prolonged hospitalization, urinary catheterization, and mechanical ventilation are more important risk factors for secondary infections in ICUs and COVID-19 does not occur an additional risk factor in prolonged ICU stay.

Single-drug versus combination antimicrobial therapy in critically ill patients with hospital-acquired pneumonia and ventilator-associated pneumonia due to Gram-negative pathogens: a multicenter retrospective cohort study

Key messagesIn this study including 391 critically ill patients with nosocomial pneumonia due to Gram-negative pathogens, combination therapy was not associated with a reduced hazard of death at Day 28 or a greater likelihood of clinical cure at Day 14. No over-risk of AKI was observed in patients receiving combination therapy.BackgroundThe benefits and harms of combination antimicrobial therapy remain controversial in critically ill patients with hospital-acquired pneumonia (HAP), ventilated HAP (vHAP) or ventilator-associated pneumonia (VAP) involving Gram-negative bacteria.MethodsWe included all patients in the prospective multicenter OutcomeRea database with a first HAP, vHAP or VAP due to a single Gram-negative bacterium and treated with initial adequate single-drug or combination therapy. The primary endpoint was Day-28 all-cause mortality. Secondary endpoints were clinical cure rate at Day 14 and a composite outcome of death or treatment-emergent acute kidney injury (AKI) at Day 7. The average effects of combination therapy on the study endpoints were investigated through inverse probability of treatment-weighted regression and multivariable regression models. Subgroups analyses were performed according to the resistance phenotype of the causative pathogens (multidrug-resistant or not), the pivotal (carbapenems or others) and companion (aminoglycosides/polymyxins or others) drug classes, the duration of combination therapy (< 3 or ≥ 3 days), the SOFA score value at pneumonia onset (< 7 or ≥ 7 points), and in patients with pneumonia due to non-fermenting Gram-negative bacteria, pneumonia-related bloodstream infection, or septic shock.ResultsAmong the 391 included patients, 151 (38.6%) received single-drug therapy and 240 (61.4%) received combination therapy. VAP (overall, 67.3%), vHAP (16.4%) and HAP (16.4%) were equally distributed in the two groups. All-cause mortality rates at Day 28 (overall, 31.2%), clinical cure rate at Day 14 (43.7%) and the rate of death or AKI at Day 7 (41.2%) did not significantly differ between the groups. In inverse probability of treatment-weighted analyses, combination therapy was not independently associated with the likelihood of all-cause death at Day 28 (adjusted odd ratio [aOR], 1.14; 95% confidence interval [CI] 0.73–1.77; P = 0.56), clinical cure at Day 14 (aOR, 0.79; 95% CI 0.53–1.20; P = 0.27) or death or AKI at Day 7 (aOR, 1.07; 95% CI 0.71–1.63; P = 0.73). Multivariable regression models and subgroup analyses provided similar results.ConclusionsInitial combination therapy exerts no independent impact on Day-28 mortality, clinical cure rate at Day 14, and the hazard of death or AKI at Day 7 in critically ill patients with mono-bacterial HAP, vHAP or VAP due to Gram-negative bacteria.

Microbiological profile and antibiotic resistance of urinary tract infections in Maternity and Children Hospital, Hafr Al Batin, Saudi Arabia within 2022

Objective: This study aimed to characterize the antibiotic sensitivity, microbial resistance, and prevalence of the bacteria responsible for urinary tract infections (UTIs) at Maternity and Children Hospital (MCH), Hafr Al Batin, Saudi Arabia. Methods: Analysis was done on 1273 culture samples that were processed in the microbiology lab between January and December of 2022. Results: In all, 1273 urine culture (UC) samples were gathered. Gram-negative bacteria accounted for 46.9% of the 1273 positive UC, followed by Gram-positive bacteria with 28.8%, fungal pathogens with 13.1%, and Gram-negative non-fermenting bacteria with 11.2%. The most common uropathogenic organism (76.8%) was Pseudomonas aeruginosa, which was followed by Escherichia coli (55.6%), Staphylococcus epidermidis (22.9%), and Klebsiella pneumonia (24.3%). Candida albicans (69.5%) was determined to be the most frequent agent in terms of fungus, followed by C. glabrata (19.2%). The study revealed that the bacterial isolates exhibited effective resistance to antimicrobial drugs such as Amikacin, Cefepime, Ciprofloxacin, Gentamicin, imipenem, Levofloxacin, and Piperacillin/Tazobactam when administered against Gram-negative bacteria. Furthermore, the most effective antibiotics against Gram‑positive was Erythromycin but were sensitive to Vancomycin. Conclusions: One of the most typical infections that affect women is bacterial urinary tract infection. Using antibiotics for a very long time, and their misuse will result in the widespread growth of resistant bacteria.

Assessing changes in the pattern of healthcare-associated infectious agents in intensive care units during a novel coronavirus infection pandemic (COVID-19)

Introduction. The novel coronavirus infection (COVID-19) pandemic has been a major challenge to the global healthcare system, affecting more than 32 million patients worldwide. Unprecedented anti-epidemic measures carried out in hospitals allowed clinicians to hope for a decrease of hospital infection, however, the pandemic exacerbated the problem of the spread and circulation of multidrug-resistant bacteria in hospitals. The goal of study to conduct a comparative assessment of changes in the microbial landscape and the level of antibiotic resistance of the main pathogens of lower respiratory tract infections in ICU patients who were in different epidemiological conditions during the COVID-19 pandemic in comparison with the “pre-Covid” period. Materials and methods. A multicenter retrospective observational cohort study was conducted, which included the ICU of 4 hospitals in Yekaterinburg, which were in different epidemiological situations during the COVID-19 pandemic, as well as a comparative analysis of the length of stay of patients in the ICU, the frequency and duration of mechanical ventilation, the resuscitation mortality rate, and also the results of microbiological examination of sputum with an assessment of the structure of pathogens and the level of their antibiotic resistance. Results. The structure of pathogens in sputum in ICU patients of the “green zone” has not fundamentally changed. In the “red zone” there was an increase in the number of documented infections of the lower respiratory tract and blood flow, while hospitals showed differences in changes in the microbial landscape. The microbiological situation in the ICU of the “red zone” was characterized by a decrease in the number of isolated strains of Enterobacterales and non-fermenting Gram-negative bacteria by the end of the pandemic, as well as a significant increase fungi in sputum. In hospitals, where there was an alternation of periods of work in the “red” and “green” zones, there was a decrease of Enterobacterales, an increase in non-fermenting Gram-negative bacteria and a fungi. Among the microflora isolated by bacteriological methods in patients with COVID-19, gram-negative bacteria and fungi predominated, mainly Klebsiella pneumonia, Acinetobacter baumanii and fungi of the Candida spp. A significant increase in the proportion of fungi in sputum was noted in ICU patients in infectious diseases hospitals during the pandemic period. An increase in the level of antibiotic resistance of the main pathogens of lower respiratory tract infections was revealed with the appearance of multi-resistant and extremely resistant strains of Klebsiella pneumoniae and Acinetobacter baumanii. Discussion. Changes in the microbial landscape may indirectly reflect the features of immune damage in patients with a new coronavirus infection COVID-19, which, combined with the severity of the disease and the characteristics of its therapy, led to an increase in complications in the form of a secondary bacterial infection. The reasons for the increase in HAI cases include: an increase in the number of patients with severe comorbidities in an artificial closed ecosystem - the “red zone”; features of the methods of treatment (glucocorticosteroids, genetically engineered biological products - IL-6 inhibitors, etc.); high frequency of unreasonable use of antibacterial drugs; increase in the duration ofuse of various invasive devices and mechanical ventilation; changing the structure and practice of staffing hospitals, increasing the number of inexperienced medical workers and volunteers; inadequate hand hygiene, use of unsuitable individual protection means with a lack of developed methods for their processing in the new conditions. Conclusion. The results obtained indicate the importance of the work of a multidisciplinary with a microbiologist, epidemiologist, clinical pharmacologist in order to improve the quality of care for patients, especially in a difficult epidemiological situation. Surveillance over the spread of HAI pathogens should be attributed to the most progressive form of anti-epidemic activity. Microbiological monitoring and its results can serve as the basis for making managerial decisions to combat and prevent hospital infections. It is the main method for assessing the etiology, phenotype, mechanisms of resistance to antimicrobial drugs, allows you to identify epidemiological relationships between diseases, reasonably prescribe antibiotic therapy, and conduct targeted purchases of drugs (antibiotics) for the needs of this hospital.

Phenotypic characteristics of environmental Pseudomonas aeruginosa: an in vitro study on epidemiological aspects

Pseudomonas aeruginosa is one of the most commonly isolated species among non-fermenting Gram-negative bacteria, both from clinical samples and from environmental sources. The survival of the species in harsh conditions is ensured by the production of a protective biofilm; assessment of biofilm-forming capacity aids future pathogen eradication strategies. The aim of our present study was to assess the relationship between antibiotic resistance, biofilm-forming capacity and other phenotypic virulence factors in environmental P. aeruginosa isolates. One hundred and fourteen (n = 114) isolates were included in the study, which were obtained from various geographical regions and environmental origins. Antimicrobial susceptibility testing was carried out using standard protocols. Biofilm-forming capacity and pyocyanin pigment production were tested using microtiter plate-based methods. Swarming, swimming and twitching motility, and siderophore-production were assessed using agar-plate based methodologies. Resistance in environmental isolates were highest for levofloxacin/ciprofloxacin 49.12% (n = 56), ceftazidime 42.98% (n = 49) and cefepime 35.96% (n = 41), while lowest for colistin 0% (n = 0); overexpression of RND-type efflux pumps was seen in 33.33% (n = 33) of isolates. 21.93% (n = 25) met the criteria to be classified as multidrug resistant (MDR). 17.54% (n = 20) of isolates were weak/non-biofilm producers, while (25.45%, n = 29) and (57.01%, n = 65) were moderate and strong biofilm producers, respectively. No significant differences were noted in biofilm-formation (OD570 values non-MDR [mean ± SD]: 0.396 ± 0.138 vs. MDR: 0.348 ± 0.181; p &gt; 0.05) or pyocyanin pigment production (OD686 values non-MDR: 0.403 ± 0.169 vs. MDR: 0.484 ± 0.125; p &gt; 0.05) between MDR and non-MDR environmental P. aeruginosa. Highest motility values were observed for swarming motility, followed by swimming and twitching motility; no relevant differences (p &gt; 0.05) in motility were noted in the context of MDR status or biofilm-formation in the tested isolates. P. aeruginosa is an opportunistic pathogen with high medical importance, being a causative agent of recalcitrant infections, which are becoming difficult to treat with the onset of MDR. Further studies are warranted to assess biofilm-forming capacity, and to provide insights into the mechanisms underlying biofilm-formation both in isolates of clinical and environmental origins.

Evolving trends among Pseudomonas aeruginosa: a 12-year retrospective study from the United Arab Emirates.

Pseudomonas is a group of ubiquitous non-fermenting Gram-negative bacteria (NFGNB). Of the several species associated with humans, Pseudomonas aeruginosa (PA) can acclimate to diverse environments. The global frequency of PA infections is rising and is complicated by this organism's high intrinsic and acquired resistance to several clinically relevant antibiotics. Data on the epidemiology, levels, and trends of antimicrobial resistance of PA in clinical settings in the MENA/GCC region is scarce. A retrospective 12-year analysis of 56,618 non-duplicate diagnostic Pseudomonas spp. from the United Arab Emirates (UAE) was conducted. Data was generated at 317 surveillance sites by routine patient care during 2010-2021, collected by trained personnel and reported by participating surveillance sites to the UAE National antimicrobial resistance (AMR) Surveillance program. Data analysis was conducted with WHONET (https://whonet.org/). Among the total isolates (N = 56,618), the majority were PA (95.6%). Data on nationality revealed 44.1% were UAE nationals. Most isolates were from soft tissue (55.7%), followed by respiratory tract (26.7%). PA was more commonly found among inpatients than among outpatients, followed by ICUs. PA showed a horizontal trend for resistance to fluoroquinolones, 3rd- and 4th-generation cephalosporins, and decreasing trends of resistance for aminoglycosides and meropenem. The highest percentage of multidrug resistant (MDR) isolates was reported in 2011 at 35.6%. As an overall trend, the percentage of MDR, extensively drug-resistant (XDR), and possible pandrug-resistant (PDR) isolates generally declined over the study period. Carbapenem-resistant PA (CRPA) were associated with a higher mortality (RR: 2.7), increased admission to ICU (RR: 2.3), and increased length of stay (LOS) (12 excess inpatient days per case), as compared to carbapenem-susceptible PA (CSPA). The resistance trends in Pseudomonas species in the UAE indicated a decline in AMR and in percentages of Pseudomonas isolates with MDR and XDR profiles. The sustained Pseudomonas spp. circulation particularly in the hospital settings highlights the importance of surveillance techniques, infection control strategies, and stewardship to limit the continued dissemination. This data also shows that CRPA are associated with higher mortality, increased ICU admission rates, and a longer hospitalization, thus higher costs due to increased number of in-hospital and ICU days.

866. A new protocol for bacterial identification and carbapenemases by MALDI-TOF and lateral flow assay directly from positive blood culture: MALDI-FAST

Abstract Background Infectious diseases are a global public health problem, accounting for more than 20% of the mortality burden. Klebsiella pneumoniae and Pseudomonas aeruginosa caused more than 1.3 million deaths globally in 2019. Antimicrobial resistance (AMR) is a major factor in this mortality. Rapid molecular test for the detection of the blaKPC gene improves treatment time and mortality in patients with bacteremia caused by carbapenem-resistant Enterobacterales, however, the use of molecular biology techniques may not be optimal in multiple resourced care settings limited. Our goal is to perform rapid identification of Gram-negative bacilli and detection of carbapenemases directly from blood cultures using the combination of mass spectrometry (MALDI-TOF) and the lateral flow immunochromatography test.4 Methods We analyzed 97 bottles of positive blood cultures detected by the BACT/Alert 3D system (BioMérieux®). Our new method (MALDI-FAST) uses 0.5ml of blood obtained from the positive blood culture bottle for Gram-negative bacilli, from which a pellet is obtained by rapid centrifugation in 3 minutes. This material is processed both for bacterial identification by MALDI-TOF mass spectrophotometry (Bruker®), and rapid detection of carbapenemases by NG Test Carba 5 lateral flow immunochromatography (NG Biotech®). The results obtained were compared with the gold standard RT-PCR FilmArray Panel BCID 2.0 (BioMérieux®) Results Of the 97 blood culture bottles, 94/97 (96.9%) were correctly identified to the species level and 3/97 (3.1%) were polymicrobial blood cultures. Klebsiella pneumoniae was detected in 39 samples, E. coli in 24, and 34 other microorganisms including non-fermenting bacteria. Excellent concordance (kappa index 1,000) was achieved in 31/97 blood cultures (31.9%) that presented carbapenemases, 18/31 KPC (18.6%) and 13/31 with KPC and NDM coproduction (13.4%). 66/97(68.15%) bottles did not present carbapenemase. Conclusion Our protocol presents very good results for bacterial identification by mass spectrometry and carbapenemase detection by lateral flow immunoassay in a few minutes directly from the positive blood culture, becoming a fast and cost-effective tool to contribute to patient management. Disclosures All Authors: No reported disclosures

Soil-specific responses in the antibiotic resistome of culturable Acinetobacter spp. and other non-fermentative Gram-negative bacteria following experimental manure application.

Acinetobacter spp. and other non-fermenting Gram-negative bacteria (NFGNB) represent an important group of opportunistic pathogens due to their propensity for multiple, intrinsic, or acquired antimicrobial resistance (AMR). Antimicrobial resistant bacteria and their genes can spread to the environment through livestock manure. This study investigated the effects of fresh manure from dairy cows under antibiotic prophylaxis on the antibiotic resistome and AMR hosts in microcosms using pasture soil. We specifically focused on culturable Acinetobacter spp. and other NFGNB using CHROMagar Acinetobacter. We conducted two 28-days incubation experiments to simulate natural deposition of fresh manure on pasture soil and evaluated the effects on antibiotic resistance genes (ARGs) and bacterial hosts through shotgun metagenomics. We found that manure application altered the abundance and composition of ARGs and their bacterial hosts, and that the effects depended on the soil source. Manure enriched the antibiotic resistome of bacteria only in the soil where native bacteria had a low abundance of ARGs. Our study highlights the role of native soil bacteria in modulating the consequences of manure deposition on soil and confirms the potential of culturable Acinetobacter spp. and other NFGNB to accumulate AMR in pasture soil receiving fresh manure.

Multidrug-resistant among Non-Fermenting Gram-negative Bacteria Isolated in the Department of Microbiology of a Tertiary Care Centre.

Infection caused by Non-fermenting Gram-negative bacteria (NFGNB) like Pseudomonas aeruginosa and Acinetobacter baumannii leads to life-threatening conditions. These bacteria are often multidrug-resistant which leads to limited therapeutic options leading to treatment failure. Little information is available regarding the prevalence and resistance pattern of such bacteria in our country. The aim of the study was to find out the prevalence of multidrug-resistant among non-fermenting Gram-negative bacteria isolated in the Department of Microbiology of a tertiary care centre. A descriptive cross-sectional study was conducted in the Department of Microbiology of a tertiary care centre from 1 September 2021 to 30 August 2022 after obtaining ethical approval from the Institutional Review Committee. All samples received in the Microbiology laboratory for diagnostic purposes were included. A convenience sampling method was used. The point estimated was calculated at a 95% Confidence Interval. Among 412 non-fermenting Gram-negative bacteria, multidrug resistance was observed in 373 (90.53%) (87.70-93.36, 95% Confidence Interval) isolates. Among 373 isolates, Acinetobacter baumannii was 253 (67.83%) and Pseudomonas aeruginosa was 120 (32.17%). The prevalence of multidrug-resistant non-fermenting Gram-negative bacteria was found to be higher than in the study conducted in similar settings. Acinetobacter baumannii; antibiotic; Pseudomonas aeruginosa; prevalence.

Evaluation of distribution and susceptibility of microorganisms isolated from joint fluid cultures: five-year data

Aims: Septic arthritis is joint inflammation. It is an orthopedic emergency that requires prompt diagnosis and treatment. In this study, it was aimed to examine the distribution and antibiotic resistance profiles of microorganisms isolated from joint fluid samples taken from patients who applied to the orthopedic clinic of our hospital in the last five years. &#x0D; Methods: In our study, 1162 joint fluid samples were sent to the medical microbiology laboratory of our hospital from the orthopedics and traumatology clinic between January 01, 2018 and December 31, 2022. Joint fluid samples taken from clinically appropriate patients under sterile conditions were incubated in a BacT/Alert 3D (Biomerieux, France) culture device. Bacteria isolated from 164 specimens with growth detected, were identified by matrix-mediated laser desorption/ionization-time-of-flight mass spectrometry (MALDI-TOF MS) based VITEK MS (Biomerieux, France). Antibiotic susceptibility tests were performed on the VITEK 2 Compact (Biomerieux, France) device.&#x0D; Results: Staphylococcus aureus (S. aureus) (29.3%) and coagulase negative Staphylococci (CNS) (29.3%) were the most commonly grown microorganisms. Other microorganisms grown were Streptococcus spp. (9.1%), Enterococcus spp. (6.1%), Pseudomonas aeruginosa (P. aeuruginosa) (7.3%), Escherichiae coli (E. coli) (4.3%) and Klebsiella pneumoniae (K. pneumoniae) (4.3%). When antibiotic susceptibility results were evaluated according to EUCAST restricted reporting criteria, linezolid in Gram-positive strains, amikacin in Enterobacterales, colistin and tigecycline in nonfermentative Gram-negative bacteria were found to be the most susceptible antibiotics. &#x0D; Conclusion: The continuous change in antibiotic susceptibility profiles in joint infections, the long duration of treatment and follow-up, and the increase in polymicrobial infections require regular monitoring of culture and antibiotic susceptibility tests. In our study, the distribution of microorganisms isolated from joint fluid samples of our hospital and the determination of antibiotic resistance profiles will contribute to the clinician in terms of guiding empirical treatment.

Efficacy of Colistin with Carbapenems Combination by Checkerboard Assay against Carbapenem Resistant Non Lactose Fermenting Gram Negative Bacteria

Recent emergence of carbapenem resistant non-fermenting Gram negative bacteria (CRNFGNB) predominantly Pseudomonas and Acinetobacter species are responsible for significant proportion of nosocomial infections with increased mortality. Of the various mechanisms known, carbapenemases especially metallo beta lactamase (MBL) mediated resistance is the most concerning because of its easy transmissibility via mobile genetic elements and lack of MBL inhibitors for clinical use. In the present study we determined to estimate the prevalence of carbapenem resistant Pseudomonas and Acinetobacter species, their resistance mechanisms by phenotypic tests and synergistic studies with Colistin and carbapenems combination by checkerboard assay. Carbapenem resistance among these two bacteria is 53.2% being isolated predominantly from pus and endotracheal secretions and from patients within the age group of less than 9 years (44%) and more than 60 years (23%). The incidence of carbapenemase and MBL production in NFGNB is 89.8% and 87.9%, respectively. Only Colistin and Tigecycline show significant antibacterial activity while most of the tested antibiotics were found to be least effective against carbapenem resistant NFGNB. Colistin and Imipenem combination demonstrated synergistic activity in majority of the NFGNB species; however, translation of such in vitro efficacy models into highly variable in vivo conditions could be possible only with strong clinical support.

Clonal diversity, antimicrobial resistance, and genome features among nonfermenting gram-negative bacteria isolated from patients with cystic fibrosis in Russia

Nonfermenting gram-negative (NFGN) bacteria were isolated from cystic fibrosis (CF) patients and subjected to susceptibility testing and whole-genome sequencing. Among 170 enrolled CF patients, 112 (65.9%) were colonized with at least 1 key NFGN species. The species-specific infection rate was highest for Pseudomonas aeruginosa (40.6%) followed by Stenotrophomonas maltophilia (14.1%), Achromobacter spp. (9.4%), and Burkholderia cepacia complex (Bcc, 8.2%) demonstrating a significant age-dependent increase for P. aeruginosa and Achromobacter spp., but not for S. maltophilia or Bcc. P. aeruginosa sequence types (STs) related to high-risk epidemic and global CF clones were carried by 12 (7.1%) and 13 (7.6%) patients, respectively. In total, 47% NFGN isolates, predominantly P. aeruginosa, harbored at least 1 plasmid-borne resistance gene; 5 ST235 isolates carried blaVIM2. Pathogenicity island-borne virulence genes were harbored by 9% NFGN isolates. These findings in conjunction with frequent early colonization by Bcc raised serious concerns regarding infection control in Russian CF centers.

Potential sources of water contamination in Sulaymaniyah city hospitals: isolation and identification of non-fermentative gram-negative bacteria

Potential sources of water contamination in Sulaymaniyah city hospitals: isolation and identification of non-fermentative gram-negative bacteria

Antibiotic resistance patterns in nosocomial infections: preliminary data from Hospital of Al-Hoceima, Morocco.

Nosocomial infections or healthcare-associated infections (HCAIs) represent a public health problem. The burden of antibiotic resistance in these infections is still unclear in Morocco. The objective of this study was to describe antibiotic susceptibility of the main bacteria responsible for nosocomial infections in order to propose prevention measures. Data were collected from 1519 laboratory records including hospital inpatients suspected of nosocomial infections in Mohamed V Hospital of Al-Hoceima between January 2016 and December 2020. The data were analyzed using SPSS software version 25. Bacteriological test samples included 65.5% of urine, 27.2% of pleural fluid, 4.5% of pus, and 2.8% of protected distal swab. Two hundred and twenty-seven (15%) samples were culture-positive. The bacteria isolated were mainly enterobacteria (Escherichia coli, 43.6% and Klebsiella pneumoniae, 13%), non-fermentative Gram-negative bacteria (Pseudomonas aeruginosa, 10.8%), and Staphylococcus aureus (24.3%). Extended spectrum beta-lactamases (ESBLs)-producing Enterobacteriaceae represented 25.4% and those resistant to other families of antibiotics accounted for 12.5%. In our study, we reported 17% ESBL producers among urinary infections. Methicillin-resistant Staphylococcus aureus accounted for 22.2%. Pseudomonas aeruginosa that were resistant to ticarcillin, ceftazidime, and imipenem represented 29% of the cases. Our results showed a higher frequency of resistance. A microbiological surveillance system is highly needed to identify bacterial niches in the hospital environment at Mohamed V Hospital.

Isolation of a rare pathogen &lt;i&gt;Chryseobacterium indologenes&lt;/i&gt; in patients with pneumonia

Introduction. Chryseobacterium indologenes bacteria are rarely detected, poorly studied opportunistic bacteria of the nonfermenting gram-negative bacilli group that are characterized by high intrinsic and acquired multidrug resistance and involvement in healthcare associated infections.Aim. To analyze detection rate of C. indologenes strains from various biomaterials obtained from patients with pneumonia, as well as levels of pathogen drug resistance to antimicrobial drugs.Materials and methods. The research included 1740 clinical samples obtained from patients with pneumonia hospitalized in in-patient facilities of the Khabarovsk city during the COVID-19 pandemic. Clinical samples included 1305 respiratory samples (744 sputum samples and 561 nasopharyngeal swabs), 435 samples of autopsy material (lung tissue) obtained from patients with a fatal outcome of the disease. The study was performed via classical bacteriological method. Pathogens were identified with Vitek 2 bacteriological analyzer and Vitek MS mass spectrometer. Sensitivity to antimicrobial drugs was determined by disk-diffusion method and in a bacteriological analyzer.Results. A comparative analysis of detection of the entire nonfermenting gram-negative bacteria (NFGNB) group and C. indologenes from various clinical samples was carried out. Detection rate of NFGNB equaled 17.3%. NFGNB were isolated from autopsy material most often ‒ in 31.7% of cases, less often ‒ from sputum and nasopharyngeal smears (13.8% and 10.7%, respectively). C. indologenes was detected in 0.5% of the cases (8 isolates out of 1740 samples). Isolation of this pathogen was most frequent in nasopharyngeal smears – in 1.1% (6 cases out of 561 samples), least frequent ‒ from sputum, which totaled 0.3% (2 isolates from 744 samples). The detection rate of the pathogen in respiratory samples equaled 0.6% (8 isolates out of 1305 samples). This pathogen was not found in the autopsy material. Carbapenem-resistant variants of C. indologenes were isolated in 75% (6 cases out of 8) of the cases.Conclusion. Further intensifying of diagnostic methods will result in more frequent detection of these unusual pathogens, clinical significance of which needs more justification.

Carbapenem is not always the best choice in the treatment of septic shock

BackgroundSeptic shock is a global public health burden. In addition to the improvement of the level of individual care, the improvement of the overall hospital quality control management is also an essential key aspect of the Surviving Sepsis Campaign (SSC). Using of antibiotics is a cornerstone in the treatment of septic shock, so we conducted this study to investigate the influence of antibiotics and pathogenic bacteria on the mortality of septic shock at the level of overall hospital in China.MethodsThis was an observational database study in 2021 enrolled the data of 787 hospitals from 31 provinces/municipalities/autonomous regions of Mainland China collected in a survey from January 1, 2021 to December 31, 2021.ResultsThe proportion of ICU patients with septic shock was 3.55%, while the patient mortality of septic shock was 23.08%. While carbapenem was the most preferred antibiotic medication used in 459 of the 782 hospitals, the preference for carbapenem did not show significant effect on the patient mortality in the treatment of septic shock (p-value 0.59). Compared with patients with fermenting bacteria as the most common pathogenic bacteria causing septic shock, patients with non-fermenting bacteria had a higher mortality (p-value 0.01).ConclusionsWhether using carbapenem as the preferred antibiotic or not, did not show effect on the patient mortality of septic shock. Compared with patients with fermenting bacteria as the most common pathogenic bacteria, patients of septic shock with non-fermenting bacteria had a higher mortality.

The microbiology and pathogenesis of nonfermenting Gram-negative infections.

This review provides an overview of most recent evidence about pathogenesis traits and virulence factors contributing to successful colonization or infection by P. aeruginosa , A. baumannii , S. maltophilia and B. cepacia complex, among the most clinically relevant nonfermenting Gram-negative bacteria (NFGNB). The growing clinical importance of NFGNB as important opportunistic pathogens causing difficult-to-treat infections in a fragile patients' population in stressed by numerous studies. Identification of novel virulence factors and deciphering of their mechanisms of action have greatly furthered our understanding of NFGNB pathogenesis, revealing that each pathogen-specific armamentarium of virulence factors (adhesins, motility, capsule, biofilm, lipopolysaccharide, exotoxins, exoenzymes, secretion systems, siderophores) can be likely responsible for the difference in the pathophysiology even in the context of a similar infection site. Emerging evidence of the immunomodulatory effect of some virulence factors is also acknowledged. NFGNB continue to be a serious global problem as cause of life-threatening opportunistic infections, owing to a highly heterogeneous content of virulence factors and their extensive number of intrinsic resistance mechanisms. Further efforts in development of novel effective antimicrobials and of alternative strategies targeting key virulence factors are warranted.

One year experience of Achromobacter bacteremia at a tertiary care hospital in Northern India.

Achromobacter is a Gram-negative, motile, obligate aerobic and non-fermentative bacterium. It is an emerging pathogen in the hospital environment as it is frequently found in various solutions. Information about the incidence and risk factors of Achromobacter bacteremia from India is limited. We conducted this study to identify the risk factors and underlying conditions predisposing to bacteremia by Achromobacter spp. and analyse the antibiotic resistance pattern of the isolates. We performed a retrospective observational study where automated blood cultures positive for Achromobacter spp. were assessed for clinical characteristics and antibiotic susceptibility patterns from January 2022 to December 2022 in the microbiology laboratory of a tertiary care centre in Northern India. A total of 14 cases (14/2435, 0.57 %) of Achromobacter spp. were identified from bloodstream infections in one year. The mean age of the patients was 37.59±23.17 years with a male predominance (8/14, 57.1 %). All patients were managed on intravenous antibiotics and intravenous access as peripheral line catheters and only 5(5/14, 35.7 %) patients were managed on central line catheters. The isolates were found highly susceptible to ticarcillin-clavulanic acid (14/14, 100.0 %) followed by fluoroquinolones (12/14, 85.72 %) and trimethoprim-sulphamethoxazole (12/14, 85.72 %). Only 57.14 % (8/14, 57.14 %) of the patients were susceptible to piperacillin-tazobactam. The all-cause 40 day mortality was observed in 35.7 % (5/14, 35.7 %) with two deaths that were directly attributable to sepsis. This study provides insight into the incidence of Achromobacter bacteremia at our centre and the necessary antibiotic therapy to combat it.