Clinical Infection Research Articles

Primjena ibuprofena u pedijatrijskoj populaciji

Fever is a common clinical issue, causing concern for parents and being the most frequent reason for visits to pediatricians and pediatric emergency services. Pain accompanies children in various pathological conditions during their growth. Although the importance of pain perception and the use of analgesics is emphasized, pain in the pediatric population is still insufficiently recognized, unlike fever. Ibuprofen is one of the most commonly used medications in the pediatric population, indicated for reducing fever, as well as relieving pain and inflammation in various diseases. The pharmacological properties of ibuprofen indicate a good safety profile with effective results, contributing to its widespread use. The most commonly expected adverse reactions, considering the mechanism of action, such as gastrointestinal bleeding, are rare in children. In a healthy child, there are no adverse effects on the kidneys; however, in conditions of dehydration or kidney disease, fluid volume should be replenished before administering ibuprofen. Given its broad application during fever caused by infection, some conditions are associated with more severe clinical skin and respiratory infections. It is also linked to exacerbations of asthma and a higher risk of asthma if used during pregnancy and the early years of life.This potential association requires additional research to be methodologically confirmed. Therefore, in this paper, through a literature review, we present the effectiveness and safety of ibuprofen use in the pediatric population in various pathological condition.

The Efficacy of Calcium Sulfate/Hydroxyapatite (CaS/HA) Gentamicin in Osteomyelitis Treatment: A Case Series

Background: Osteomyelitis is a challenging condition caused by infection and inflammation of the bone, presenting a significant economic burden to healthcare systems. Calcium sulfate/hydroxyapatite (CaS/HA) is a bone void filler composed of 60% calcium sulfate and 40% hydroxyapatite. This case series aimed to report the efficacy and infection-related outcomes of CaS/HA combined with Gentamicin (CaS/HA-G) in treating osteomyelitis. Methods: Patients aged 18 and older diagnosed with osteomyelitis requiring surgical intervention and treated with CaS/HA-G during their procedure were included in the study, with a median (Q1–Q3) = 10 (7–16)-month follow-up period of time. Data collected included demographic, surgical, and outcome information. Infection eradication was determined by the normalization of the C-reactive protein, erythrocyte sedimentation rate levels, or the absence of clinical infection symptoms. Results: The case series involved 21 patients (twelve male, nine female) with a mean (SD) age of 54.8 (16.6) years. Vancomycin or/and Tobramycin were used as an additional antibiotic in 17 patients. At the last follow-up, 20 out of 21 patients (95.2%) had eradicated the infection, with a median (Q1–Q3) eradication time of 128 (71.8–233.5) days. Conclusions: In conclusion, this study demonstrates that CaS/HA-G is effective in controlling osseous infection in osteomyelitis while acting as an absorbable bone void filler.

Clinical characteristics of diabetes patients complicated with COVID-19

Patients with both diabetes and coronavirus disease 2019 (COVID-19) are more likely to experience negative outcomes. This study aimed to identify the risk factors associated with these adverse outcomes that can assist clinicians in implementing suitable treatment strategies to minimize the occurrence of severe complications. A total of 92 patients with diabetes and COVID-19 in the Endocrine Department of Zhejiang Provincial Hospital of Chinese Medicine from December 2022 to February 2023 were enrolled and divided into the recovered group and the transfer to the intensive care unit (ICU) or death group. The clinical characteristics and infection indicators were compared between the 2 groups. Additionally, the patients were further divided into the normal group and the reduction group based on their glomerular filtration rate (GFR), and their clinical characteristics and infection indicators were also analyzed. Compared with the GFR normal group, the GFR reduction group exhibited worse outcomes, higher COVID-19 severity, a higher proportion of mechanical ventilation, and a longer hospital stay. However, there were no significant differences in leukocyte, lymphocyte, and neutrophil counts between these 2 groups. Compared with the recovered group, the transfer to ICU or death group demonstrated an increase in leukocytes and neutrophils, while lymphocytes decreased (P < .05). The C-reactive protein, procalcitonin, interleukin-6, and serum amyloid A levels in the transfer to ICU or death group were significantly higher than those in the Recovered group (P < .05). In addition, C-reactive protein, procalcitonin, and serum amyloid A levels in the GFR reduction group were significantly higher than those in the normal group (P < .05), while interleukin-6 levels were only slightly higher (P > .05). In clinical treatment, it is necessary to monitor infection indicators and GFR closely and intervene in time to reduce the occurrence of adverse events.

Clinical characteristics and bloodstream infection pathogens by gram-negative bacteria in different aged adults: A retrospective study

This study aims to determine the characteristics and distribution of pathogenic bacteria in bloodstream infections (BSIs) by gram-negative bacteria in adults. One hundred seventy-one adult patients with BSIs who were treated at the Affiliated Hospital of Chengde Medical College between January 2018 and January 2020 were included in this study. The patients were assigned to the young- and middle-aged group and elderly group based on age. General patient data were analyzed. More elderly patients had BSIs and gram-negative bacteria than young- and middle-aged patients. The incidence of underlying diseases in elderly patients was significantly higher than the young- and middle-aged patients (P < .01). The composition of Brucella spp. was significantly different between the elderly group and young- and middle-aged group (P < .05). There were significantly more gallbladder infections in the elderly group than the young- and middle-aged group, and significantly fewer elderly patients had no definite infection sites than the young- and middle-aged group (P < .05). The incidence of complications and in-hospital mortality in the elderly group was higher than the young- and middle-aged group (P < .05). BSIs caused by gram-negative bacteria mainly involved elderly patients. BSIs were characterized by complications and a poor prognosis, as well as pathogenic bacteria and primary infection sites.

Development of a rapid, culture-free, universal microbial identification system using internal transcribed spacer targeting primers.

The indiscriminate administration of broad-spectrum antibiotics is a primary contributor to the increasing prevalence of antibiotic resistance. Unfortunately, culture, the gold standard for bacterial identification is a time intensive process. Due to this extended diagnostic period, broad-spectrum antibiotics are generally prescribed to prevent poor outcomes. To overcome the deficits of culture-based methods, we have developed a rapid universal bacterial identification system. The platform utilizes a unique universal polymerase chain reaction (PCR) primer set that targets the internal transcribed spacer (ITS) regions between conserved bacterial genes, creating a distinguishable amplicon signature for every bacterial species. Bioinformatic simulation demonstrates that at least 45 commonly isolated pathogenic species can be uniquely identified using this approach. We experimentally confirmed these predictions on a representative set of pathogenic bacterial species. We also show that the system can determine the corresponding concentration of each pathogen. Finally, we validated performance in clinical urinary tract infection samples.

Evaluation of the Microbiology of Removed Punctal Plugs and Intracanalicular Devices.

The purpose of this observational study was to characterize the microorganisms colonizing punctal plugs and intracanalicular stents. Devices were removed from participants who previously underwent placement of punctal plugs for tear insufficiency and lacrimal stents for dacryocystorhinostomy and canalicular reconstruction procedures. After removal of the devices, they were cultured for organisms both with and without sonication to loosen any biofilms or adherent microorganisms. Primary outcome measures included culture positivity, identification of isolated microorganisms, recovery of microorganisms from culture after sonication, and clinical evidence of ocular infection. There were no cases of clinical infection. A total of 181 specimens were processed (174 punctal plugs, seven intracanalicular stents), of which 98 (54%) were culture positive. Of the punctal plugs, 92 (52.9%) were culture positive, including 42 with a single organism isolated, whereas 22 yielded two organisms, 7 yielded three organisms, and the remaining 21 yielded a polymicrobial culture with four or more organisms. The most common isolates from punctal plugs were coagulase negative staphylococci (27.6%), diphtheroids (16.4%), and streptococcus viridans (10.2%). Those plugs with polymicrobial culture results grew a mixture of organisms most consistent with skin or upper respiratory flora. Of the intracanalicular stents, 6 (85.6%) were culture positive. Punctal plugs and intracanalicular devices can become colonized with bacteria composed of oropharyngeal flora, skin flora, and other rare but potentially significant pathogens.

First-Genome Sequence Data of an Alcaligenes nematophilus Strain EBU-23 Encoding bla Gene Implicated in Acute Childhood Gastroenteritis.

Although an environmental contaminant, Alcaligenes sp. are now increasingly reported in clinical infections. Here, we present a whole-genome sequence of an extended spectrum beta-lactamase (ESBL) Alcaligenes nematophilus strain EBU-23 encoding beta-lactamase, bla gene, isolated from the stool of a hospitalized infant with acute gastroenteritis in a tertiary hospital in Nigeria. Antibiotics susceptibility test revealed that the isolate was resistant to the β-lactams, cephalosporins, and penicillin, β-lactam combination, and the fluoroquinolones. Genomic analysis exposed the presence of a class A beta-lactam hydrolase gene and multiple multidrug efflux permease which may be responsible for the beta-lactamase and multidrug resistance observed with the isolate. To the best our knowledge, we describe the first whole-genome sequence of a multidrug-resistant A. nematophilus implicated in acute childhood gastroenteritis in Nigeria.

Guanethidine Enhances the Antibacterial Activity of Rifampicin Against Multidrug-Resistant Bacteria

The escalating global threat of antibiotic resistance necessitates innovative strategies, such as the combination of antibiotics with adjuvants. Monotherapy with rifampicin is more likely to induce resistance in pathogens compared to other antibiotics. Herein, we found that the antihypertensive drug guanethidine enhanced the activity of rifampicin against certain clinically resistant Gram-negative bacteria, resulting in a reduction of up to 128-fold in the minimum inhibitory concentration. In infected animal models, this combination has achieved treatment benefits, including increased survival and decreased bacterial burden. The antimicrobial mechanism of guanethidine in synergy with rifampicin involves the disruption of the outer membrane of Gram-negative bacteria, leading to dissipation of the proton motive force. This results in an increase in reactive oxygen species and a reduction in ATP synthesis, severely disturbing energy metabolism and ultimately increasing bacterial mortality. In summary, guanethidine has the potential to become a novel adjuvant for rifampicin, offering a new option for the treatment of clinical Gram-negative bacterial infections.

Gastrointestinal helminths of Cattle slaughtered at Gwagwalada abattoir, federal capital territory, Nigeria

Gastrointestinal parasites are widespread in cattle worldwide, causing both clinical and sub-clinical infections that can lead to significant financial losses. This study investigated the prevalence of gastrointestinal helminths infection in cattle slaughtered in the abattoir at Gwagwalada area council, federal capital territory, Nigeria. A total of 120 faecal samples were collected and analysed by flotation and sedimentation methods. The results revealed an overall prevalence of 26.67%. The helminths identified were Toxocara sp (5.00%), Schistosoma sp (10.83%), and Fasciola sp (10.83%). These findings were compared to existing studies, with variations attributed to differences in climatic conditions, management practices, and seasonal factors. Age, breed, and sex-specific analyses revealed significant differences in infection rates. While no helminth infection was found in young adult cattle (1≤3 years), a 31.37% prevalence was recorded in older adult cattle (≥3 years). Among the breeds examined, Sokoto Gudali showed the highest prevalence (100%), followed by White Fulani (26.42%) and Red Fulani (16.67%). A significant breed-related difference (p = 0.0001) was recorded. Additionally, male cattle exhibited a higher prevalence (31.37%) compared to (0.00%) in females. The study highlighted the impact of geographical, ecological, and environmental factors on helminths infection, as well as the need for strategic anthelmintic treatment, improved livestock management, and educational programs to control these infections. Regular monitoring and selective breeding may further contribute to long-term infection control in cattle populations.

Herd immunity and sustainable development goals: role of nurses in strengthening primary health care

Herd immunity has proven as a highly valuable public health concept for dealing with reinfection. It is the immunity developed in a population to an infectious disease through vaccination or previous infection which is contributed by the virulence of the organism, susceptibility of an individual to infection, extent of immunity developed towards the pathogen, occurrence of clinical and subclinical infection in the herd and herd structure. Herd immunity assessment is imperative for continuously monitoring the risk of epidemics. The minimum proportion of the population that needs to be immune to herd effect is called herd immunity threshold which can be achieved through adequate immunization coverage. Immunization contributes to 14 out of its 17 sustainable development goals (SDGs) and is important in reaching SDGs. Nurses play a vital role in strengthening primary health care through vaccination campaigns, addressing vaccine hesitancy, community outreach programs, monitoring and surveillance of diseases, advocacy, and policy development. Nurse practitioners and nurse-led vaccination programs help in reaching underserved communities or groups with vaccine hesitancy and lead to an upsurge in vaccination rates, patient satisfaction, and attainment of community immunity. Thus, vaccination is a powerful, cost-effective public health tool to achieve the eradication of diseases through proper coverage and development of population immunity.

Genomic characterization of Pantoea dispersa A003 isolated from a clinical patient

IntroductionPantoea dispersa is a Gram-negative bacterium generally considered as a plant pathogen and rarely causes human infections. To date, there have been 13 studies that have documented clinical infections linked to P. dispersa, with a primary emphasis on the initial identification of this pathogen. The genomic features and the mechanisms underlying the pathogenesis of P. dispersa remain largely uninvestigated. In the present study, we describe a clinical infection caused by P. dispersa and provide the first genomic analysis of this bacterium.MethodsThe bacterial strain designated A003 was isolated from blood samples. Preliminary identification of strain A003 was conducted using matrix-assisted laser desorption ionization time-of-flight (MALDI-TOF) technology (VITEK® MS, bioMérieux, France). Biochemical and antimicrobial susceptibility assessments were carried out utilizing the VITEK-2 compact automated microbial analysis system (bioMérieux, France). Additionally, whole genome sequencing and subsequent analysis were performed to further elucidate the potential pathogenicity.ResultsThe bacterial isolate was cultured overnight at 35°C in a CO2-enriched environment on Columbia blood agar, resulting in the appearance of a white, smooth, Gram-negative rod-shaped bacterium with diameters ranging from 1 to 2 mm. Identification of strain A003 was achieved with a high confidence level of 99.9% as P. dispersa using MALDI-TOF mass spectrometry. The average nucleotide identity (ANI) value between strain A003 and the reference strain P. dispersa DSM 30073T was 98.08%, while the DNA–DNA hybridization (DDH) value was 84.10% (Formula 2) based on genome sequencing data, which further confirmed that A003 belonged to the P. dispersa species. Comprehensive analysis revealed the presence of 372 virulence factors, 15 antibiotic resistance genes, 222 carbohydrate-active enzymes, and 666 genes related to Type III secretion system (T3SS) effector proteins, as identified through the core databases of VFDB (Virulence Factors of Pathogenic Bacteria), CARD (Comprehensive Antibiotic Resistance Database), CAZY (Carbohydrate-Active enZYmes Database), and T3SS. The virulence factors included type IV pili (TFP), type VI secretion system, flagella, iron uptake system, and ompA, which are implicated in bacterial pathogenicity. The antibiotic resistance profile indicated resistance to fluoroquinolones, cephalosporins, penams, macrolides, and aminoglycosides, as annotated by the CARD database.ConclusionThe draft genome sequenced represents the inaugural genomic sequence of P. dispersa derived from clinical sources. This advancement may enhance clinical practitioners’ comprehension of the organism’s clinical attributes and serve as a foundational resource for future research into its virulence, antibiotic resistance, and host–pathogen interactions.

Effect of Sugammadex on Postoperative Pulmonary Complications and Rapid Recovery in Lung Cancer Patients Treated with Video-Assisted Thoracic Surgery: A Retrospective Cohort Study.

This study aimed to investigate the effects of sugammadex on postoperative pulmonary complications and rapid recovery in lung cancer patients undergoing video-assisted thoracic surgery (VATS). A retrospective analysis was conducted on the clinical data of 1131 lung cancer patients. Of these, 631 patients received sugammadex at the end of anesthesia, while 500 patients did not. To mitigate potential confounding factors, propensity score matching (PSM) was employed at a 1:1 ratio. After matching, 435 patients were obtained from each group. Patients who received sugammadex at the end of anesthesia were classified into Group S (n = 435) and those who did not receive sugammadex were Group P (n = 435). Postoperative pulmonary complications, indicators of recovery after surgery, nausea and vomiting, pain and lung infection scores and biochemical indices were compared between the two groups. Compared to Group P, Group S demonstrated statistically significant improvements across multiple perioperative and postoperative outcomes. Group S exhibited a lower incidence of postoperative pulmonary complications (χ2 = 9.52, p = 0.002), as well as reduced durations for several key time intervals: from the cessation of muscle relaxation to extubation (Z = 12.96, p < 0.001), from the conclusion of surgery to extubation (Z = 13.66, p < 0.001), and total operating theatre occupancy (Z = 5.81, p < 0.001). Furthermore, Group S showed accelerated recovery in terms of time to first oral intake (drink: Z = 3.80, p < 0.001; eat: Z = 3.80, p < 0.001), time to defecate (Z = 3.25, p = 0.001), and time to chest tube removal (Z = 5.04, p < 0.001). Pain management outcomes were also superior in Group S, with lower motor visual analogue scale (VAS) scores at both 24 h (Z = 4.71, p < 0.001) and 48 h (Z = 5.05, p < 0.001) postoperatively. Group S additionally demonstrated a lower modified Clinical Pulmonary Infection Score (mCPIS) (Z = 4.68, p < 0.001), reduced complication rates during the general anesthesia awakening period (χ2 = 23.54, p < 0.001), and a lower incidence of renal function abnormalities (χ2 =12.65, p < 0.001). Certain parameters, including total hospital stay duration and postoperative drainage volume, did not differ significantly between the two groups (p > 0.05). Sugammadex can effectively reduce the incidence of postoperative pulmonary complications in lung cancer patients treated with VATS, and help promote their rapid postoperative recovery with significant clinical benefits.

Amino acid competition shapes Acinetobacter baumannii gut carriage.

Antimicrobial resistance is an urgent threat to human health. Asymptomatic colonization is often critical for persistence of antimicrobial-resistant pathogens. Gut colonization by the antimicrobial-resistant priority pathogen Acinetobacter baumannii is associated with increased risk of clinical infection. Ecological factors shaping A. baumannii gut colonization remain unclear. Here we show that A. baumannii and other pathogenic Acinetobacter evolved to utilize the amino acid ornithine, a non- preferred carbon source. A. baumannii utilizes ornithine to compete with the resident microbiota and persist in the gut in mice. Supplemental dietary ornithine promotes long-term fecal shedding of A. baumannii . By contrast, supplementation of a preferred carbon source-monosodium glutamate (MSG)- abolishes the requirement for A. baumannii ornithine catabolism. Additionally, we report evidence for diet promoting A. baumannii gut carriage in humans. Together, these results highlight that evolution of ornithine catabolism allows A. baumannii to compete with the microbiota in the gut, a reservoir for pathogen spread.

Analyzing Antibiotic Resistance: A Comparative Study of E. coli Isolates from Wastewater and Clinical UTI Samples at a University Community in Grenada, West Indies

Abstract Introduction/Objective The rise of antibiotic resistance poses a significant global health threat, needing a robust monitoring system to track its emergence and spread. However, most developing countries lack the infrastructure to monitor such resistance effectively. Wastewater-based epidemiology (WBE) has been proven effective in surveilling various outbreaks and offers a promising method for monitoring antibiotic resistance at the community level. This study aims to assess and compare the antibiotic resistance of Escherichia coli isolated from raw wastewater with those isolated from clinical urinary tract infection (UTI) samples from the same community. Methods/Case Report Conducted from January 2022 to October 2023, this study analyzed antibiogram data from eighty-six Escherichia coli isolates sourced from wastewater and thirty-four isolates derived from clinical urinary tract infections (UTIs). The clinical samples were obtained and processed at the Clinical Microbiology Laboratory of a university campus. The isolates were evaluated against the eleven most prescribed antibiotics for UTIs in the University Clinic including: Amoxicillin/Clavulanic Acid, Ampicillin, Cefazolin, Cefoxitin, Ceftriaxone, Cefuroxime, Ciprofloxacin, Gentamicin, Nalidixic Acid, Nitrofurantoin, and Sulfamethoxazole-trimethoprim. Results (if a Case Study enter NA) Explaining the observed trends in both wastewater and clinical samples from the perspective of AWaRE-WHO classification (Access, Watch, Reserve), we see similar trends of resistance in both data sets. A) The antibiotics used in the Access category (Empiric first or second choice for treatment of most common infections) demonstrates similar resistance patterns for both wastewater and clinical isolates except for Nitrofurantoin. B) The antibiotics used in the Watch category (Antibiotics that have higher toxicity issues and higher potential to negatively impact AMR) resistance pattern shows negligible risk in the university community evaluated. Conclusion It is recommended that the university clinic prescribe Nitrofurantoin as the last antibiotic from the Access list to the university community to treat UTI patients. Furthermore, WBE is a useful tool to determine patterns of resistance under the studied settings.

Interference Between S. Aureus and P. Aeruginosa Clinical Isolates

General Background: Understanding microbial interactions between Pseudomonas aeruginosa and Staphylococcus aureus is crucial for clinical infections, as they often coexist and influence each other's growth and virulence. Specific Background: Both organisms are known for their ability to form biofilms and exhibit multidrug resistance (MDR), complicating treatment strategies in hospitalized patients. Knowledge Gap: Previous studies have explored the virulence of P. aeruginosa and S. aureus, but there is limited understanding of their direct in vitro interactions, particularly in protease and lipase production. Aims: The study examined the interaction between P. aeruginosa and S. aureus isolates in hospitalized patients' sputum, urine, and blood samples, focusing on virulence factors, biofilm formation, and antibiotic resistance patterns. Results: In Diyala, Iraq, 50 clinical isolates showed P. aeruginosa as protease producers, lipase producers, and biofilm producers, with significant MDR phenotypes in both species. Novelty: This study highlights the ability of P. aeruginosa to produce staphylolysin, offering novel insights into the antagonistic mechanisms that may suppress S. aureus in co-infections. Implications: The study emphasizes the significance of understanding microbial interactions in clinical infections, particularly in biofilm-associated MDR infections, to improve treatment outcomes and guide more effective therapeutic approaches. Highlights: P. aeruginosa staphylolysin inhibits S. aureus growth in vitro. Both bacteria produce biofilms and exhibit multidrug resistance. Microbial interactions impact infection severity and treatment strategies. Keywords: Microbial interactions, Pseudomonas aeruginosa, Staphylococcus aureus, Biofilm, Multidrug resistance

Ceftriaxone versus cefepime or carbapenems for definitive treatment of low-risk AmpC-Harboring Enterobacterales bloodstream infections in hospitalized adults: A retrospective cohort study

ObjectiveTo compare outcomes of ceftriaxone to AmpC-stable therapies in patients with bacteremia caused by low-risk AmpC harboring Enterobacterales. MethodsIRB-approved, retrospective cohort of hospitalized patients ≥18 years old with Serratia marcescens, Morganella morganii, or Providencia spp. bacteremia from 1/1/2017-2/28/2024. Patients were compared by definitive therapy with ceftriaxone vs AmpC-stable therapy (cefepime, carbapenem). The primary endpoint was 30-day all-cause mortality; secondary endpoints were clinical failure and development of ceftriaxone resistance. Results163 patients were included; 33.1 % received ceftriaxone, 66.9 % AmpC-stable therapies. 30-day all-cause mortality was 9.3 % ceftriaxone vs 10.1 % AmpC stable patients (P = 0.87); ceftriaxone definitive therapy was not associated with 30-day all-cause mortality (adjOR, 0.79; 95 %CI, 0.23-2.3). There were no differences in clinical failure (9.3 % vs 21.1 %, P = 0.059) or relapsing infection (5.6 % vs 9.3 %, P = 0.55) between ceftriaxone and AmpC-stable treated patients. ConclusionsPatients treated with definitive ceftriaxone for low-risk AmpC Enterobacterales bacteremia had similar outcomes to AmpC stable therapies.

Surveillance of fever and neutropenia episodes at Yeolyan Hematology and Oncology Center in Armenia

Abstract Background Fever and neutropenia frequently occur as complications in pediatric patients with malignancies, significantly escalating morbidity and mortality if not appropriately addressed. We implemented a fever registry to identify patient factors and outcomes associated with fever in patients undergoing treatment at our facility. Methods We conducted a single-center prospective observational study at the Pediatric Cancer and Blood Disorders Center of Armenia. All patients aged 0-21 years with a malignancy diagnosis and developing fever and neutropenia between June 25 and November 20, 2023, were included. Variables collected included age, gender, date and time of fever onset, patient symptoms, time to antibiotic administration, identified microbiologic and clinical infections, and subsequent outcomes, including mortality and requirement for critical care level interventions. Data were entered in Microsoft Excel 2016 and analyzed using descriptive statistical methods. Results Sixty-one patient episodes in 36 patients met the inclusion criteria. Of these, 22% of episodes had fever at home. The most common malignancy was acute leukemia, specifically B-ALL (21/61), followed by T-ALL (9/61), AML (7/61), and mixed T- and B-type (1/61). Eight out of 61 fever episodes occurred in patients with relapsed disease. The median time-to-antibiotics was 100 minutes (max: 24 hours 40 minutes) in patients developing fever outside the hospital; for inpatient cases, the median time-to-antibiotics was 30 minutes (max: 6 hours 45 minutes). The time-to-antibiotics was longer for patients experiencing fever at home compared to those in inpatient settings (p=0.043). 21% of patient episodes were pretreated, however 11 out of 61 patient episodes (18%) had a positive blood culture. Of 13 total positive cultures, ten were obtained at the time of the patient’s presentation. The most common pathogens identified were Staphylococcus spp. (8/13) including coagulase-negative (3/8), and Klebsiella spp. (3/13). Polymicrobial-positive cultures were observed during two fever and neutropenia episodes. During 35 episodes, patients presented with no complaints except for general weakness. Among the identified sources of infection (20/61), central-line-related bloodstream infections (n=6), bacteremia (n=5), and Clostridiodes difficile colitis (n=5) were the most common. One febrile neutropenia episode resulted in death (1.6%). Conclusion In summary, over 75% of episodes were observed among patients with hematologic malignancies, and localizing symptoms were absent in half of episodes at presentation. We have identified opportunities for quality improvement in time to administration of antibiotics in outpatient fever episodes. The adaptation of an electronic-based medical record system will simplify the tracking process for a febrile episode.

Characterizing the urobiome in geriatric males with chronic indwelling urinary catheters: an exploratory longitudinal study.

The impact of chronic indwelling urinary catheters (IUCs) on the composition and stability of the urinary microbiota remains unknown. The primary aim of this study was to describe the urinary microbiomes of geriatric males with chronic IUCs. A secondary aim was to explore clinical catheter-associated urinary tract infection (CAUTI) courses of the participants. Geriatric male patients with chronic IUCs were followed longitudinally. Catheterized urine, catheter tips, and both urethral and periurethral swabs were collected from participants at monthly intervals. Microbes were isolated and identified from each specimen using an enhanced culture method called expanded quantitative urine culture (EQUC) and targeted 16S rRNA gene DNA sequencing. Microbial outcomes were examined both in the absence of urinary symptoms and in the context of clinical diagnosis of CAUTI. Ten male participants (mean age 86 years) were enrolled. Urinary microbiomes differed for each participant. However, within each individual, microbiomes were similar over time and across niches (bladder, catheter, urethra, and periurethra). Within-niche microbiomes differed across individuals, and this was observed over time. The most abundant bacteria isolated from all niches were known uropathogens. Six of 10 individuals met diagnostic criteria for CAUTI at least once during the 12-month observation period, but no evidence of this or antibiotic treatment/response was discernable in our monthly samples. The microbiomes of each participant were unique and remained similar over time and across niches. Longitudinal EQUC or 16S rRNA gene sequencing data could be useful to clinicians when diagnosing or treating possible CAUTI.IMPORTANCECatheter-associated urinary tract infections (CAUTIs) are serious but preventable nosocomial infections. The most common risk factor for developing CAUTI is prolonged use of indwelling urinary catheters (IUCs). This study provides the first longitudinal description of the urinary microbiomes of geriatric males with chronic IUCs, in the absence of urinary signs and symptoms, as a first step toward enhancing our knowledge of the impact of chronic IUCs on the composition and stability of the urinary microbiota. This is an understudied area, particularly for males.

Investigation of Citrobacter freundii clinical isolates in a Chinese hospital during 2020-2022 revealed genomic characterization of an extremely drug-resistant C. freundii ST257 clinical strain GMU8049 co-carrying blaNDM-1 and a novel blaCMY variant.

The emergence of multidrug-resistant Citrobacter freundii poses a significant threat to public health. C. freundii isolates were collected from clinical patients in a Chinese hospital during 2020-2022. An unusual strain, GMU8049, was not susceptible to any of the antibiotics tested, including the novel β-lactam/β-lactamase inhibitor combination ceftazidime-avibactam. Whole-genome sequencing (WGS) revealed that GMU8049 harbors a circular chromosome belonging to the rare ST257 and an IncX3 resistance plasmid. Genomic analysis revealed the coexistence of two β-lactamase genes, including plasmid-mediated blaNDM-1 and chromosomal blaCMY encoding a novel CMY variant, combined with an outer membrane porin deficiency, which may account for the extreme resistance to β-lactams. Conjugation experiment confirmed that the blaNDM-1 resistance gene located on pGMU8049 could be successfully transferred to Escherichia coli EC600. The novel CMY variant had an amino acid substitution at position 106 (N106S) compared to the closely related CMY-51. Additionally, a GMU8049-specific truncation in an OmpK37 variant that produces a premature stop codon. Moreover, a variety of chromosome-located efflux pump coding genes and virulence-related genes were also identified. Analysis of strain GMU8049 in the context of other C. freundii strains reveals an open pan-genome and the presence of mobile genetic elements that can mediate horizontal gene transfer of antimicrobial resistance and virulence genes. Our work provides comprehensive insights into the genetic mechanisms of highly resistant C. freundii, highlighting the importance of genomic surveillance of this opportunistic pathogen as a high-risk population for emerging resistance and pathogenicity.IMPORTANCEEmerging pathogens exhibiting multi-, extremely, and pan-drug resistance are a major concern for hospitalized patients and the healthcare community due to limited antimicrobial treatment options and the potential for spread. Genomic technologies have enabled clinical surveillance of emerging pathogens and modeling of the evolution and transmission of antimicrobial resistance and virulence. Here, we report the genomic characterization of an extremely drug-resistant ST257 Citrobacter freundii clinical isolate. Genomic analysis of GMU8049 with a rare ST type and unusual phenotypes can provide information on how this extremely resistant clinical isolate has evolved, including the acquisition of blaNDM-1 via the IncX3 plasmid and accumulation through chromosomal mutations leading to a novel CMY variant and deficiency of the outer membrane porin OmpK37. Our work highlights that the emergence of extremely resistant C. freundii poses a significant challenge to the treatment of clinical infections. Therefore, great efforts must be made to specifically monitor this opportunistic pathogen.

Characterization of clinical infection and drug resistance of group B streptococcus in Chengdu, China

ObjectiveTo investigate the clinical infection characteristics and antibiotic resistance of Group B Streptococcus (Streptococcus agalactiae, GBS) in Chengdu, China, from 2019 to 2021, as well as to provide data to support rational clinical drug use. MethodsThis was a retrospective study to collect 203 culture-positive GBS strains isolated from January 2019 to December 2021 in Chengdu, China, all of which were identified by the VITEK 2 Compact automated microbial Bacterial identification instrument. Data were derived using WHONET 5.6 software. The sample type and ward distribution were counted. Pregnant women and newborns were screened from the original data and their pregnancy outcomes were calculated respectively. ResultsGBS strains were mainly concentrated in obstetrics and neonatology departments, accounting for 40.9 % and 33.5 %. The types of specimens were mainly vaginal secretions, amniotic fluid and sputum, accounting for 25.6 %, 26.1 % and 18.7 %, respectively. Chorioamnionitis, premature rupture of membranes and preterm delivery occurred mainly in pregnant women after infection, accounting for 44.4 %, 31.5 % and 24.1 %. Neonates, on the other hand, were mainly diagnosed with neonatal pneumonia, neonatal sepsis, respiratory failure and septic meningitis, accounting for 91.8 %, 61.2 %, 44.9 % and 16.3 % of all positive neonates. 840 pregnant women were screened for GBS colonization from 2019 to 2021, and a total of 108 GBS positive pregnant women were identified, with a GBS colonization rate of 12.9 %. A total of 9 neonates from 108 GBS positive pregnant women developed early-onset disease. The morbidity in neonates was 8.3 %. No strains resistant to penicillin and ampicillin were found, while the resistance rates of tetracycline and clindamycin were higher than 50 %, respectively 60.1 % and 53.2 %. ConclusionGBS infection mainly affected pregnant women and newborns in Chengdu, China, which can lead to adverse maternal and infant outcomes. Attention should be paid to strengthening general screening of GBS in perinatal urogenital secretions and the prevention strategy of IAP (intrapartum antibiotic prophylaxis). Antimicrobial therapy should be administered with appropriate antibiotics. Penicillin was still the first line drug for the treatment of GBS. These initiatives were important to reduce mother-to-child transmission and neonatal infections.