Despite the improved outcomes in patients with hematological malignancies, infections caused by multidrug-resistant organisms (MDROs) pose a new threat to these patients. We retrospectively reviewed the patients with hematological cancer and bacterial bloodstream infections (BSIs) at a tertiary hospital between 2003 and 2022 to assess the impact of MDROs on outcomes. Among 328 BSIs, 81 (24.7%) were caused by MDROs. MDRO rates increased from 10.3% (2003-2007) to 39.7% (2018-2022) (P < 0.001). The 30-day mortality rate was 25.0%, which was significantly higher in MDRO-infected patients than in non-MDRO-infected patients (48.1 vs. 17.4%; P < 0.001). The observed trend was more pronounced in patients with newly diagnosed diseases and relapsed/refractory disease but less prominent in patients in complete remission. Among MDROs, carbapenem-resistant Gram-negative bacteria exhibited the highest mortality, followed by vancomycin-resistant enterococci, methicillin-resistant Staphylococcus aureus, and extended-spectrum β-lactamase-producing Enterobacteriaceae. Multivariate analysis identified independent risk factors for 30-day mortality as age ≥ 65 years, newly diagnosed disease, relapsed/refractory disease, MDROs, polymicrobial infection, CRP ≥ 20 mg/L, and inappropriate initial antibiotic therapy. In conclusion, MDROs contribute to adverse outcomes in patients with hematological cancer and bacterial BSIs, with effects varying based on the underlying disease status and causative pathogens. Appropriate initial antibiotic therapy may improve patient outcomes.

BACKGROUND: Before the COVID-19 pandemic there has been a constant increase in antimicrobial resistance (AMR) of Escherichia coli, the most common cause of urinary tract infections and bloodstream infections. The aim of this study was to investigate the impact of the COVID-19 pandemic on extended-spectrum β-lactamase (ESBL) production in urine and blood E. coli isolates in Finland to improve our understanding on the source attribution of this major multidrug-resistant pathogen.
METHODS: Susceptibility test results of 564,233 urine (88.3% from females) and 23,860 blood E. coli isolates (58.8% from females) were obtained from the nationwide surveillance database of Finnish clinical microbiology laboratories. Susceptibility testing was performed according to EUCAST guidelines. We compared ESBL-producing E. coli proportions and incidence before (2018-2019), during (2020-2021), and after (2022) the pandemic and stratified these by age groups and sex.
RESULTS: The annual number of urine E. coli isolates tested for antimicrobial susceptibility decreased 23.3% during 2018-2022 whereas the number of blood E. coli isolates increased 1.1%. The annual proportion of ESBL-producing E. coli in urine E. coli isolates decreased 28.7% among males, from 6.9% (average during 2018-2019) to 4.9% in 2022, and 28.7% among females, from 3.0 to 2.1%. In blood E. coli isolates, the proportion decreased 32.9% among males, from 9.3 to 6.2%, and 26.6% among females, from 6.2 to 4.6%. A significant decreasing trend was also observed in most age groups, but risk remained highest among persons aged ≥ 60 years.
CONCLUSIONS: The reduction in the proportions of ESBL-producing E. coli was comprehensive, covering both specimen types, both sexes, and all age groups, showing that the continuously increasing trends could be reversed. Decrease in international travel and antimicrobial use were likely behind this reduction, suggesting that informing travellers about the risk of multidrug-resistant bacteria, hygiene measures, and appropriate antimicrobial use is crucial in prevention. Evaluation of infection control measures in healthcare settings could be beneficial, especially in long-term care.

UNASSIGNED: Nosocomial bloodstream infections associated with intravascular catheters pose significant financial burden, morbidity, and mortality. There is much debate about whether or not blood cultures should be drawn through central venous catheters, and while guidelines advocate for catheter-drawn cultures when catheter infection is suspected, there is variable practice in this regard.
UNASSIGNED: We performed a retrospective cohort study assessing episodes of positive catheter-drawn blood cultures with concomitant negative percutaneously-drawn cultures in tertiary care hospitals in the United States and Spain.
UNASSIGNED: We identified 143 episodes in 122 patients meeting inclusion criteria. Thirty percent of such episodes revealed growth of potential pathogens such as Staphylococcus aureus. Overall, 21% of follow-up percutaneously-drawn blood cultures obtained within 48 hours revealed growth of the same microbe after an episode of positive catheter-drawn blood cultures with negative concomitant percutaneously-drawn cultures (33% when potential pathogens were isolated; 16% when common skin contaminants were isolated). Patients with cultures growing pathogenic organisms were more likely to receive targeted antimicrobial therapy and have their catheters removed sooner.
UNASSIGNED: Many episodes of positive catheter-drawn blood cultures with concomitant negative percutaneously-drawn cultures lead to growth from percutaneously-drawn follow-up blood cultures. Thus, such initial discordant results should not be disregarded. Our findings advocate for a nuanced approach to blood culture interpretation, emphasizing the value of catheter-drawn blood cultures in clinical decision making and management.

Cytomegalovirus reactivation (CMVr) and bloodstream infections (BSI) are the most common infectious complications in patients after allogeneic haematopoietic stem cell transplantation (allo-HSCT). Both are associated with great high morbidity whilst the BSI is the leading cause of mortality. This retrospective study evaluated the incidence of CMVr and BSI, identified associated risk factors, assessed their impact on survival in allo-HSCT recipients during the first 100 days after transplantation. The study comprised 500 allo-HSCT recipients who were CMV DNA-negative and CMV IgG-positive before allo-HSCT. Amongst them, 400 developed CMVr and 75 experienced BSI within 100 days after allo-HSCT. Multivariate regression revealed that graft failure and acute graft-versus-host disease were significant risk factors for poor prognosis, whereas CMVr or BSI alone were not. Amongst all 500 patients, 56 (14%) developed both CMVr and BSI in the 100 days after HSCT, showing significantly reduced 6-month overall survival (p = 0.003) and long-term survival (p = 0.002). Specifically, in the initial post-transplant phase (within 60 days), BSI significantly elevate mortality risk, However, patients who survive BSI during this critical period subsequently experience a lower mortality risk. Nevertheless, the presence of CMVr in patients with BSI considerably diminishes their long-term survival prospects. This study provides real-world data on the impact of CMVr and BSI following transplantation on survival, particularly in regions such as China, where the prevalence of CMV IgG-positivity is high. The findings underscore the necessity for devising and executing focused prevention and early management strategies for CMVr and BSI to enhance outcomes for allo-HSCT recipients.

UNASSIGNED: The Stenotrophomonas maltophilia complex (Smc) has emerged as a significant nosocomial pathogen contributing to increased mortality rates, particularly in case of bloodstream infections.
UNASSIGNED: This study employed whole-genome sequencing (WGS) to assess the genetic diversity, antimicrobial resistance profiles, molecular epidemiology and frequencies of virulence genes among 55 S. maltophilia isolates obtained from bacteremic cases over a 9-year period.
UNASSIGNED: Based on the threshold of 95% average nucleotide identity (ANI) and 70% digital DNA-DNA hybridization (dDDH) for genospecies delineation, we classified 37 isolates into 6 known species, all belonging to the Smc. The remaining 18 isolates sequenced in this study were assigned to 6 new genomospecies. Among the 55 isolates, we identified 44 different sequence types (STs), comprising 22 known and 22 novel allele combinations. The resistance rate of Smc against trimethoprim-sulfamethoxazole (TMP/SMX) was found to be 3.6%, with the sul1 and class one integron integrase genes (intI) detected in these isolates. All Smc isolates were susceptible to minocycline. Furthermore, all Smc strains harbored the motA, pilU, smf-1 and Stmpr2 genes. Genomospecies 1 (100%, n = 9), Stenotrophomonas maltophilia (84.21%, n = 19) and Stenotrophomonas sepilia (71.43%, n = 7) demonstrated a higher percentage of the afaD gene, which was also associated with a higher separation rate. In addition to motA, pilU, smf-1, and Stmpr2 genes, all S. maltophilia strains (100%) contained entA, gspD, KatA, and stmPr1 genes, while all genomospecies 1 strains (100%) contained afaD, entA, gspD, and KatA genes.
UNASSIGNED: Our study highlights the genetic diversity among Smc isolates from patients with bacteremia, revealing 22 novel ST types, 58 new alleles and 6 new genomospecies. S. maltophilia and S. pavanii were found to carry more virulence factors, emphasizing the importance of accurate strain identification. Minocycline emerged as a promising alternative antibiotic for patients who were resistant to TMP/SMX.

In 2022, an outbreak with severe bloodstream infections caused by Serratia marcescens occurred in an adult intensive care unit (ICU) in Hungary. Eight cases, five of whom died, were detected. Initial control measures could not stop the outbreak. We conducted a matched case-control study. In univariable analysis, the cases were more likely to be located around one sink in the ICU and had more medical procedures and medications than the controls, however, the multivariable analysis was not conclusive. Isolates from blood cultures of the cases and the ICU environment were closely related by whole genome sequencing and resistant or tolerant against the quaternary ammonium compound surface disinfectant used in the ICU. Thus, S. marcescens was able to survive in the environment despite regular cleaning and disinfection. The hospital replaced the disinfectant with another one, tightened the cleaning protocol and strengthened hand hygiene compliance among the healthcare workers. Together, these control measures have proved effective to prevent new cases. Our results highlight the importance of multidisciplinary outbreak investigations, including environmental sampling, molecular typing and testing for disinfectant resistance.

OBJECTIVE: Bloodstream infections in patients with COVID-19 are linked to higher mortality rates, whilst data on epidemiology and resistance patterns remains scarce to guide management and prevent antibiotic resistance. This research focuses on the prevalence, clinical features, causative microorganisms, and antimicrobial susceptibility of bacterial and fungal secondary bloodstream co-infections in hospitalized patients with COVID-19.
METHODS: In this retrospective study analysis of 230 patients with COVID-19 from Central Taiwan (June 2021 to June 2022), pathogens were identified via MALDI-TOF MS and Vitek 2 system with Clinical & Laboratory Standards Institute (CLSI) standards.
RESULTS: In the cohort, 17.8% experienced bloodstream infections, resulting in a total of 45 isolates from the 41 bloodstream infection patients: predominantly gram-positive bacteria (Staphylococcus and Enterococcus) at 69%, gram-negative at 29% (Escherichia coli and Klebsiella pneumoniae), and fungi at 2%. Infected patients showed significantly elevated levels of white blood count (WBC), C-reactive protein (CRP) and procalcitonin (PCT). Of note, resistance to common antibiotics, such as fluoroquinolones, cephalosporins, and oxacillin was significant, especially in K. pneumoniae, Acinetobacter species, and S. aureus infections.
CONCLUSIONS: Our study highlights the influence of bacterial infections in hospitalized patients with COVID-19. The bacterial infections were discovered to impact the clinical trajectory of COVID-19, potentially exacerbating or mitigating its symptoms, severity and fatality. These insights are pivotal to addressing clinical challenges in COVID-19 management and underscoring the need for tailored medical interventions. Understanding these co-infections is thus essential for optimizing patient care and improving overall outcomes in the post COVID-19 pandemic era.

Central line-associated bloodstream infections (CLABSIs) are the most frequent pediatric hospital-acquired infections and significantly impact outcomes. The aim of this study was to estimate the attributable mortality for CLABSIs in pediatric and neonatal patients in Greece. A retrospective matched-cohort study was performed, in two tertiary pediatric hospitals. Inpatients with a central line in neonatal and pediatric intensive care units (NICUs and PICUs), hematology/oncology units, and a bone marrow transplantation unit between June 2012 and June 2015 were eligible. Patients with confirmed CLABSI were enrolled on the day of the event and were matched (1:1) to non-CLABSI patients by hospital, hospitalization unit, and length of stay prior to study enrollment (188 children enrolled, 94 CLABSIs). Attributable mortality was estimated. During the study period, 22 patients with CLABSI and nine non-CLABSI patients died (23.4 vs. 9.6%, respectively, p  = 0.011), leading to an attributable mortality of 13.8% (95% confidence interval [CI] = 3.4-24.3%). Children in PICUs were more likely to die, presenting an attributable mortality of 20.2% (95% CI = - 1.4-41.8%), without reaching, however, statistical significance. After multiple logistic regression, patients with CLABSI were four times more likely to die (odds ratio [OR] = 4.29, 95% CI = 1.28-14.36, p  = 0.018). Survival analysis showed no difference in time to death after study enrollment between patients with CLABSI and non-CLABSI patients (log-rank p  = 0.137, overall median survival time = 7.8 months). Greek pediatric mortality rates are increased by the CLABSI occurrence, highlighting the importance of infection prevention strategies.

BACKGROUND: Although central line-associated bloodstream infection (CLABSI) is the most common type of healthcare-associated infection among patients with inserted devices, few studies have comprehensively evaluated the related risk factors.
OBJECTIVE: This retrospective study analyzed the risk factors, predictors, causative organisms, and impact of CLABSI on clinical outcomes mortality, and length of stay (LOS) in older adults.
METHODS: We included 36 patients diagnosed with CLABSI according to the Centers for Disease Control and Prevention criteria at King Abdulaziz University Hospital during 2013-2014 cases and 375 control patients controls. Risk factors were evaluated using a multivariate logistic regression analysis.
RESULTS: Cases and controls did not differ significantly in age or sex distribution. However, cases had a significantly longer LOS than controls 78 vs. 19 days, p < 0.001. One-third of 12/36 CLABSI cases were admitted to the medical intensive care unit (MICU). Most had renal disease, acute coronary syndrome, and used steroids. Additionally, 34 cases (94.4%) and 2 cases (5.6%) presented with primary and secondary infections, respectively, and hypotension was the most prevalent symptom (12/36). The internal jugular vein was the most common insertion site, and the nasogastric tube and mechanical ventilator were the most common insertion devices. Seven cases died, and three deaths were attributed to bloodstream infection (BSI). The most common cause of blood infection was Staphylococcus epidermidis, followed by Klebsiella pneumoniae.
CONCLUSIONS: The present study reveals age, LOS, total parenteral nutrition/partial parenteral nutrition (TPN/PPN), and transplantation as the independent risk factors/predictors of CLABSI.

UNASSIGNED: Meropenem-vaborbactam is a recent and promising option for the treatment of KPC-producing Klebsiella pneumoniae (KPC-Kp) infections, including those resistant to ceftazidime-avibactam.
UNASSIGNED: We conducted a retrospective analysis of observational data from 19 Italian hospitals on use and outcomes of patients treated with meropenem-vaborbactam for at least ≥24 hours for KPC-Kp infections. Crude and propensity-weighted multiple Cox regression models were performed to ascertain risk factors independently associated with 30-day mortality.
UNASSIGNED: The cohort included 342 adults with bloodstream infections (n = 172) and nonbacteremic infections (n = 170), of which 107 were lower respiratory tract infections, 30 were complicated urinary tract infections, and 33 were infections involving other sites. Most infections (62.3%) were managed with meropenem-vaborbactam monotherapy, or in combination with at least 1 other active drug (usually fosfomycin, tigecycline, or gentamicin) (37.7%). The 30-day mortality rate was 31.6% (108/342). In multiple Cox regression model, 30-day mortality was independently associated with septic shock at infection onset, Charlson comorbidity index ≥ 3, dialysis, concomitant COVID-19, and INCREMENT score ≥ 8. Administration of meropenem-vaborbactam within 48 hours from infection onset was a negative predictor of mortality. All predictors, except administration of meropenem-vaborbactam within 48 hours, remained significant when the multiple Cox regression model was repeated after adjustment for the propensity score for receipt of combination therapy.
UNASSIGNED: Despite the limits of a retrospective study, the data derived from this multicenter cohort provide additional evidence on the efficacy of meropenem-vaborbactam in treating severe KPC-Kp infections, even when used as monotherapy.