Gram-negative Sepsis Research Articles

Efficacy and Safety of Injection Sepsivac® (Heat-killed Mycobacterium W) in Gram-negative Sepsis administered via an Intravenous Route.

As an immunomodulator, the mycobacterium w (Mw) has improved outcomes for patients suffering from severe sepsis. The traditional route of administration for Mw is intradermal (ID), which is limited to administering 0.1 mL per injection (Inj). The intravenous (IV) route can be an alternative to ID. To evaluate the safety and efficacy of Inj Sepsivac® IV in gram-negative sepsis. Present retrospective observational study was conducted in an intensive care unit (ICU) of tertiary care hospital. The study included 30 consecutive patients with presumed gram-negative sepsis within 48 hours of the first organ dysfunction. Patients received Inj Sepsivac® 0.3 mL diluted in 100 mL normal saline to be given as slow IV infusions over at least 15 minutes, every day for 3 consecutive days. Efficacy was assessed by recording the change in vital parameters, sequential organ failure assessment (SOFA) score, and laboratory investigations. Safety was evaluated by the occurrence of allergic reactions including anaphylaxis, the site of infection, and secondary infection. Each patient was followed up for 14 days from the day of enrolment. Mean age of patients with gram-negative sepsis was 62.67 ± 12.77 years with male preponderance (63.3%). Pneumonia (40.1%) and intraabdominal infections (26.7%) were the most common etiologies of sepsis. A significant improvement in all the vitals and mean SOFA scores was observed from day 2 onward. More than half of the patients required ventilator support [17 (56.7%)], and mortality was observed in 7 (25%) patients. None was reported to have a secondary infection. Laboratory parameters improved and oxygen requirement was reduced postday 4 till the end of treatment from baseline. The IV route of administration was found to be efficacious and safe and allow ease of administration in treating gram-negative sepsis. Further large multicentric randomized trials are required to confirm our findings.

SAMHD1 Attenuates Acute Inflammation by Maintaining Mitochondrial Function in Macrophages via Interaction with VDAC1.

Over-activation of Toll-like receptor 4 (TLR4) is the key mechanism in Gram-negative bacterial infection-induced sepsis. SAM and HD domain-containing deoxynucleoside triphosphate triphosphohydrolase 1 (SAMHD1) inhibits multiple viruses, but whether it plays a role during bacterial invasion remains unelucidated. Monocyte-macrophage specific Samhd1 knockout (Samhd1-/-) mice and Samhd1-/- macrophage cell line RAW264.7 were constructed and used as research models to evaluate the role of SAMHD1 in TLR4-activated inflammation. In vivo, LPS-challenged Samhd1-/- mice showed higher serum inflammatory factors, accompanied with more severe inflammation infiltration and lower survival rate. In vitro, Samhd1-/- peritoneal macrophages had more activated TLR4 pathway upon LPS-stimulation, accompanied with mitochondrial depolarization and dysfunction and a higher tendency to be M1-polarized. These results could be rescued by overexpressing full-length wild-type SAMHD1 or its phospho-mimetic T634D mutant into Samhd1-/- RAW264.7 cells, whereas the mutants, dNTP hydrolase-function-deprived H238A and phospho-ablative T634A, did not exert the same effect. Lastly, co-IP and immunofluorescence assays confirmed that SAMHD1 interacted with an outer mitochondrial membrane-localized protein, voltage-dependent anion channel-1 (VDAC1). SAMHD1 inhibits TLR4-induced acute inflammation and M1 polarization of macrophages by interacting with VDAC1 and maintaining mitochondria function, which outlines a novel regulatory mechanism of TLR signaling upon LPS stimulation.

Severe and fatal COVID-19 is characterised by increased circulating glucagon like peptide 1 and procalcitonin modulated by type 2 diabetes.

Endotoxemia commonly occurs in severe and fatal COVID-19, suggesting that concomitant bacterial stimuli may amplify the innate immune response induced by SARS-CoV-2. We previously demonstrated that the endogenous glucagon like peptide 1 (GLP-1) system in conjunction with increased procalcitonin (PCT) is hyperactivated in patients with severe Gram-negative sepsis and modulated by type 2 diabetes (T2D). We aimed to determine the association of COVID-19 severity with endogenous GLP-1 activation upregulated by increased specific pro-inflammatory innate immune response in patients with and withoutT2D. Plasma levels of total GLP-1, IL-6, and PCT were estimated on admission and during hospitalisation in 61 patients (17 with T2D) with non-severe and severe COVID-19. COVID-19 patients demonstrated ten-fold increase of IL-6 levels regardless of disease severity. Increased admission GLP-1 levels (p=0.03) accompanied by two-fold increased PCT were found in severe as compared with non-severe patients. Moreover, GLP-1 and PCT levels were significantly increased in non-survived as compared with survived patients at admission (p=0.01 and p=0.001, respectively) and at 5 to 6days of hospitalisation (p=0.05). Both non-diabetic and T2D patients demonstrated a positive correlation between GLP-1 and PCT response (r=0.33, p=0.03, and r=0.54, p=0.03, respectively), but the intensity of this joint pro-inflammatory/GLP-1 response was modulated by T2D. In addition, hypoxaemia down-regulated GLP-1 response only in T2D patients with bilateral lung damage. The persistent joint increase of endogenous GLP-1 and PCT in severe and fatal COVID-19 suggests a role of concomitant bacterial infection in disease exacerbation. Early elevation of endogenous GLP-1 may serve as a new biomarker of COVID-19 severity and fatal outcome.

Update Management of Chemotherapy-Induced Neutropenia: A Narrative Literature Review

One of the most frequent and significant complicated side effects of myelosuppressive drugs is neutropenia. Neutropenia is not only associated with high morbidity but also mortality. Generally, the onset of neutropenia occurs within 3-7 days after the administration of anticancer agents. Approximately 5-30% of patients will develop febrile neutropenia. The highest incidence occurs during the first cycle of chemotherapy. This literature review aimed to describe chemotherapy-induced neutropenia and its prevention and management. Administration of granulocyte colony-stimulating factor as prophylaxis can prevent neutropenia-induced anticancer drugs. The use of granulocyte colony-stimulating factor (G-CSF) as therapeutic is contradictive, and some guidelines recommend not to use the G-CSF for therapeutic purposes. Up to 70% of mortality among these populations was associated with gram-negative sepsis, therefor empirical antibiotics, and antifungals are the keys to the management of neutropenia. In conclusion, prevention and appropriate management of neutropenia are extremely important in the treatment of patients with cancer.

Fecal Volatile Metabolomics Predict Gram-Negative Late-Onset Sepsis in Preterm Infants: A Nationwide Case-Control Study.

Early detection of late-onset sepsis (LOS) in preterm infants is crucial since timely treatment initiation is a key prognostic factor. We hypothesized that fecal volatile organic compounds (VOCs), reflecting microbiota composition and function, could serve as a non-invasive biomarker for preclinical pathogen-specific LOS detection. Fecal samples and clinical data of all preterm infants (≤30 weeks' gestation) admitted at nine neonatal intensive care units in the Netherlands and Belgium were collected daily. Samples from one to three days before LOS onset were analyzed by gas chromatography-ion mobility spectrometry (GC-IMS), a technique based on pattern recognition, and gas chromatography-time of flight-mass spectrometry (GC-TOF-MS), to identify unique metabolites. Fecal VOC profiles and metabolites from infants with LOS were compared with matched controls. Samples from 121 LOS infants and 121 matched controls were analyzed using GC-IMS, and from 34 LOS infants and 34 matched controls using GC-TOF-MS. Differences in fecal VOCs were most profound one and two days preceding Escherichia coli LOS (Area Under Curve; p-value: 0.73; p = 0.02, 0.83; p < 0.002, respectively) and two and three days before gram-negative LOS (0.81; p < 0.001, 0.85; p < 0.001, respectively). GC-TOF-MS identified pathogen-specific discriminative metabolites for LOS. This study underlines the potential for VOCs as a non-invasive preclinical diagnostic LOS biomarker.

Microbiological Findings and Clinical Outcomes in Ugandan Patients with Infected Burn Wounds

Nosocomial wound infections are a dreaded complication in patients with burns. However, access to the necessary microbiological diagnostics is impaired in low-resource settings. This prospective observational cohort study aimed to describe the bacterial pathogens, resistance profiles and clinical outcomes of patients with wound infections admitted to the largest specialized unit for burns and plastic surgery in Uganda. Blood and wound swab cultures were taken for bacterial species identification and antibiotic susceptibility testing. A total of 140 patients (female: n = 62, 44.3%) with a median age of 26 (IQR 7–35) years were included between October 2020 and April 2022, of which the majority (n = 101, 72.2%) had burn wounds (72.3% Grade 2b, 14.9% Grade 3). Gram-negative Enterobacterales, Pseudomonas spp. and Acinetobacter spp. were most commonly isolated from wound swabs and nearly all isolates were multidrug resistant with very limited treatment options. While the clinical outcome was favorable in 21 (15%) study participants, the majority were left with disabilities (minor: n = 41, 29.3%, moderate: n = 52, 37%, major: n = 14 (10%)). Twelve (8.6%) study participants died, mostly of Gram-negative sepsis. Our findings highlight the urgent need for routine access to microbiological diagnostics to improve patient care and local surveillance efforts on antimicrobial resistance.

Endotoxin content in neonatal formulas, fortification, and lactoferrin products: association with outcomes and guidance on acceptable limits

While endotoxin (lipopolysaccharide) can be harmful and contribute to morbidity and mortality with Gram-negative sepsis or necrotizing enterocolitis in preterm infants, non-toxic amounts are produced as part of the neonatal microbiome and may be present in enteral nutrition and medications administered. The United States Food and Drug Administration has given guidance for endotoxin concentration limits for intravenous medications and fluids of 5 endotoxin units/kg/hour (120 endotoxin units/kg/day), but no guidance for amounts of endotoxin in enteral products. To determine baseline exposure to infants in the neonatal intensive care unit, we examined endotoxin content of enteral formulas and fortification used for preterm infants, as well as bovine lactoferrin products. We also examined endotoxin exposure and outcomes in very low birth weight infants. Endotoxin content was measured using kinetic chromogenic limulus amebocyte lysate analysis. Daily endotoxin exposure from enteral formulas ranged between < 75 to 7110 endotoxin units/kg and from lactoferrin products from 7 to 3720 endotoxin units/kg. In examining neonatal outcomes from a bovine lactoferrin product studied at three different escalating doses (100, 200, and 300 mg/kg/day), we measured endotoxin in the lactoferrin product and daily exposure was 1089 (N = 10), 2178 (N = 10) and 3287 (N = 11) endotoxin units/kg, respectively. There were no cases of necrotizing enterocolitis or mortality and no lactoferrin-related adverse effects in these patients. Enteral endotoxin daily exposures from lactoferrin products are similar to amounts in preterm enteral nutrition and appear safe and not associated with patient harm. Testing enteral products and establishing safety limits may improve care of high risk patients.

Gram-negative bacterial infection causes aggravated innate immune response in sepsis: Studies from clinical samples and cellular models

Bacterial infection is the most common cause for sepsis. The purpose of this study was to evaluate the impact of different bacterial infection on sepsis based on human samples and cellular experiments. Physiological indexes and prognostic information of 121 sepsis patients were analysed based on whether they had a gram-positive or gram-negative bacterial infection. Moreover, murine RAW264.7 macrophages were treated with lipopolysaccharide (LPS) or peptidoglycan (PG) to simulate infection with gram-negative or gram-positive bacteria in sepsis, respectively. Exosomes derived from the macrophages were extracted for transcriptome sequencing. In patients with sepsis, most gram-positive bacterial infections were Staphylococcus aureus, and gram-negative infections were Escherichia coli. Gram-negative bacterial infection was significantly associated with high neutrophil and interleukin (IL)-6 levels in blood and shorter prothrombin (PT) and activated partial thromboplastin time (APTT). Intriguingly, the survival prognosis of sepsis patients was not affected by the type of bacterial infection, but it was significantly related to fibrinogen. Protein transcriptome sequencing of the macrophage-derived exosomes showed that differentially expressed proteins were significantly enriched in megakaryocyte differentiation, leukocyte and lymphocyte-mediated immunity, and complement and coagulation cascade pathways. The complement and coagulation-related proteins were significantly upregulated after LPS induction, which explained the shortened PT and APTT in gram-negative bacterial sepsis. Bacterial infection did not affect mortality in sepsis but did alter the host response. The immune disorder induced by gram-negative infection was more severe than that produced by gram-positive infection. This study provides references for the rapid identification and molecular research of different bacterial infections in sepsis.

Gram-negative Late Onset Neonatal Sepsis in a Tertiary Care Center From Central India: A Retrospective Analysis.

Neonatal sepsis has been a major cause of neonatal mortality and morbidity globally. Late onset sepsis is on the rise mostly due to better health care services and improved survival of premature neonates. Gram-negative sepsis has emerged as a major public health problem constituting significant morbidity and mortality. There is limited data on gram-negative late onset sepsis from the central part of India, therefore this study was conducted at a tertiary care center from rural part of India. To determine the clinical profile and outcome among neonates with gram-negative late onset sepsis. It is a retrospective analysis conducted among neonates with gram-negative late onset sepsis at a tertiary care center from central India. All neonates below 28 days of age suspected to have late onset sepsis were enrolled in the study. The data for the period of January 2019 to December 2021 was collected and analyzed using software SPSS version 29. The outcome variables studied were discharge (good outcome) and death (poor outcome). In the present study, overall prevalence of gram-negative late onset sepsis was 4.8%. Respiratory distress (52.2%), seizure (18.9%), jaundice (15.6%), and lethargy (15.6%) were common clinical symptoms among neonates with sepsis. The most common organism isolated was Klebsiella spp. (36.7%) followed by Acinetobacter spp. (31.1%) and E. coli (17.8%). Low gestational age (n = 20 vs n = 7, P = .002) and low birth weight (n = 33 vs n = 4, P = .02) were associated with poor outcomes in neonates with gram negative LOS. The overall mortality rate was found to be 30% among neonates with gram negative sepsis. The prevalence of gram-negative sepsis was found to be 4.8%. Factors associated with poor outcome in gram-negative sepsis were low birth weight, and prematurity. Klebsiella spp. was found to be a common cause of gram-negative LOS, therefore, the empiric antibiotic policy must provide coverage against these micro-organisms.

Efficacy and safety of heat-killed Mycobacterium w in Gram-negative sepsis: Prospective study of intravenous administration.

Efficacy and safety of heat-killed Mycobacterium w in Gram-negative sepsis: Prospective study of intravenous administration.

Mycobacterium Indicus Pranii (MIP) Vaccine: Pharmacology, Indication, Dosing Schedules, Administration, and Side Effects in Clinical Practice

Mycobacterium indicus pranii (MIP), previously called Mw vaccine, is a one-of-a-kind immunomodulatory vaccine. It was indigenously developed in India for use in leprosy. MIP is heat-killed Mycobacterium w, which is a non-pathogenic atypical mycobacterium belonging to Class IV of Runyon classification. It shares epitopes with Mycobacterium leprae and Mycobacterium tuberculosis, which forms the rationale behind its use in leprosy and tuberculosis. MIP activates both innate and acquired immunity. It induces a Th1 and Th17 immune response along with downregulation of Th2 pathway and activates macrophages and dendritic cells. MIP vaccine is safe with adverse effects such as local site erythema, swelling, and rarely fever and other systemic reactions. Apart from leprosy, MIP has been used in dermatological diseases such as warts and psoriasis. Clinical trials have evaluated the efficacy of MIP in a plenitude of non-dermatological conditions such as category II tuberculosis, Gram-negative sepsis, non-small cell lung cancer, human immunodeficiency virus (HIV), muscle-invasive bladder cancer, and very recently, coronavirus 2019 (COVID-19). In vitro and animal studies have also demonstrated its utility in leishmaniasis, melanoma, and as a vaccine for the prevention of pregnancy. The PubMed database was searched using “Mycobacterium indicus pranii, MIP, Mycobacterium w” as the keyword in title. This comprehensive review provides useful information for healthcare professionals about immunotherapeutic potential of MIP vaccine, its composition, dosing schedule, administration, and side effects besides its efficacy in various indications other than leprosy.

Predictive role of selected biomarkers in differentiating gram-positive from gram-negative sepsis in surgical patients: a retrospective study.

Patients after major surgery are at high risk of developing sepsis, which is accompanied by elevated serum levels of C-reactive protein (CRP) and procalcitonin (PCT). This study aimed to examine the differences in serum biomarker levels concerning the causative agent of sepsis in surgical patients. A retrospective study was carried out in the surgical intensive care unit (ICU) and included 81 septic patients admitted from January 2019 to May 2022, who had positive blood cultures (BC). Serum levels of PCT, CRP, white blood cells (WBC) and platelet counts were recorded on the day of the positive BC and over the following 3 days. Patients with gram(-) sepsis had significantly higher PCT levels, and lower platelet count compared to patients with gram(+) sepsis. High PCT and low platelets levels in all measurements were a significant predictor of gram(-) isolate with the highest predictive value on the third day after BC sampling, with AUROC 0.821 (95% CI: 0.692-0.950), P = 0.001, and AUROC 0.676 (95% CI: 0.541-0.811), P = 0.02, respectively. In multivariate logistic regression, platelets the day after BC sampling and PCT on the third day made a significant contribution in distinguishing gam(+) from gram(-) BC. Age and high serum CRP levels were significant predictors of poor outcomes. PCT and platelets may be useful biomarkers for predicting the causative agent of sepsis in surgical patients.

Continuous Infusion of High Doses of Cefepime in Intensive Care Unit: Assessment of Steady-State Plasma Level and Incidence on Neurotoxicity.

Continuous infusion (CI) with high doses of cefepime is recommended in the empirical antimicrobial regimen of critically ill patients with suspected Gram-negative sepsis. This study aimed to determine factors associated with cefepime overdosing and the incidence of cefepime-induced neurotoxicity (CIN) in these patients. We performed a retrospective study including all patients receiving cefepime treatment between January 2019 and May 2022. The plasma level of cefepime defining overdosing was over 35 mg/L. Neurotoxicity was defined according to strict criteria and correlated with concomitant steady-state concentration of cefepime. Seventy-eight courses of cefepime treatment were analyzed. The mean cefepime plasma level at steady state was 59.8 ± 29.3 mg/L, and overdosing occurred in 80% of patients. Renal failure and a daily dose &gt; 5 g were independently associated with overdosing. CIN was present in 30% of patients. In multivariate analysis, factors associated with CIN were chronic renal failure and a cefepime plasma concentration ≥ 60 mg/L. CIN was not associated with mortality. Overdosing is frequent in patients receiving high doses of cefepime by CI. Steady-state levels are higher than targeted therapeutic pharmacokinetic/pharmacodynamic objectives. The risk of CIN is important when the plasma concentration is ≥60 mg/L.

Evaluating IL-6 and IL-10 as rapid diagnostic tools for Gram-negative bacteria and as disease severity predictors in pediatric sepsis patients in the intensive care unit.

To explore the diagnostic performance of interleukin (IL)-6 and IL-10 in discriminating Gram bacteria types and predicting disease severity in intensive care unit (ICU)-hospitalized pediatric sepsis patients. We retrospectively collected Th1/Th2 cytokine profiles of 146 microbiologically documented sepsis patients. Patients were categorized into Gram-positive (G+) or Gram-negative (G-) sepsis groups, and cytokine levels were compared. Subgroup analysis was designed to eliminate the influence of other inflammatory responses on cytokine levels. After propensity score matching, 78 patients were matched and categorized according to Gram bacteria types. Compared with G+ sepsis, IL-6 and IL-10 were significantly elevated in G- sepsis (p < 0.05). Spearman test proved the linear correlation between IL-6 and IL-10 (r = 0.654, p < 0.001), and their combination indicators (ratio and differences) were effective in identifying G- sepsis. In the subgroup analysis, such cytokine elevation was significant regardless of primary infection site. However, for patients with progressively deteriorating organ function [new or progressive multiple organ dysfunction syndrome (NPMODS)], differences in IL-6 and IL-10 levels were less significant between G+ and G- sepsis. In the receiver operating characteristic (ROC) curves of the G- sepsis group, the area under the curve (AUC) value for IL-6 and IL-10 was 0.679 (95% CI 0.561-0.798) and 0.637 (95% CI 0.512-0.762), respectively. The optimal cutoff value for diagnosing G- sepsis was 76.77 pg/ml and 18.90 pg/ml, respectively. While for the NPMODS group, the AUC for IL-6 and IL-10 was 0.834 (95% CI 0.766-0.902) and 0.781 (95% CI 0.701-0.860), respectively. IL-6 and IL-10 are comparably effective in discriminating G+/G- sepsis in pediatric intensive care unit (PICU) patients. The deteriorated organ function observed in ICU patients reveals that complex inflammatory responses might have contributed to the cytokine pattern observed in severe sepsis patients, therefore confounding the discriminating efficacy of Th1/Th2 cytokines in predicting Gram bacteria types.

The cholesteryl-ester transfer protein isoform (CETPI) and derived peptides: new targets in the study of Gram-negative sepsis

BackgroundSepsis is a syndrome where the dysregulated host response to infection threatens the life of the patient. The isoform of the cholesteryl-ester transfer protein (CETPI) is synthesized in the small intestine, and it is present in human plasma. CETPI and peptides derived from its C-terminal sequence present the ability to bind and deactivate bacterial lipopolysaccharides (LPS). The present study establishes the relationship between the plasma levels of CETPI and disease severity of sepsis due to Gram-negative bacteria.MethodsPlasma samples from healthy subjects and patients with positive blood culture for Gram-negative bacteria were collected at the Intensive Care Unit (ICU) of INCMNSZ (Mexico City). 47 healthy subjects, 50 patients with infection, and 55 patients with sepsis and septic shock, were enrolled in this study. CETPI plasma levels were measured by an enzyme-linked immunosorbent assay and its expression confirmed by Western Blot analysis. Plasma cytokines (IL-1β, TNFα, IL-6, IL-8, IL-12p70, IFNγ, and IL-10) were measured in both, healthy subjects, and patients, and directly correlated with their CETPI plasma levels and severity of clinical parameters. Sequential Organ Failure Assessment (SOFA) scores were evaluated at ICU admission and within 24 h of admission. Plasma LPS and CETPI levels were also measured and studied in patients with liver dysfunction.ResultsThe level of CETPI in plasma was found to be higher in patients with positive blood culture for Gram-negative bacteria that in control subjects, showing a direct correlation with their SOFA values. Accordingly, septic shock patients showing a high CETPI plasma concentration, presented a negative correlation with cytokines IL-8, IL-1β, and IL-10. Also, in patients with liver dysfunction, since higher CETPI levels correlated with a high plasma LPS concentration, LPS neutralization carried out by CETPI might be considered a physiological response that will have to be studied in detail.ConclusionsElevated levels of plasma CETPI were associated with disease severity and organ failure in patients with Gram-negative bacteraemia, defining CETPI as a protein implicated in the systemic response to LPS.

Early-Onset Neonatal Sepsis in Turkey: A Single-Center 7-Year Experience in Etiology and Antibiotic Susceptibility.

The pathogen distribution and antibiotic susceptibility of the pathogens in early-onset sepsis (EOS) differ between countries. The epidemiological data from a limited number of studies about EOS in Turkey are insufficient. In this study, we aimed to evaluate the culture-proven EOS cases, causative microorganisms, antibiotic susceptibility patterns, and risk factors for mortality in EOS. This is a retrospective, single-center study over a 7-year period, from 2013 to 2020, at Zeynep Kamil Maternity and Children's Hospital, İstanbul, Turkey. During the study period, 8229 newborns were admitted to our neonatal intensive care unit. Culture-proven EOS was detected in 101 patients (0.12%). Out of these, 56 (55.4%) were Gram-positive, and 45 (44.5%) were Gram-negative sepsis. The most common isolated organism was E. coli (28.7%, n = 29), followed by GBS (16.8%, n = 17) and S. aureus (15.8%, n = 16). An ampicillin and gentamicin combination had antimicrobial coverage in 92.6% of cases. Seventeen patients (16.8%) died because of EOS. Severe neutropenia was found to be an independent risk factor for mortality in EOS (p = 0.001, OR = 14.4, CI 95%: 2.8-74). Although the majority of causative agents were Gram-positive (55.4%), the most common isolated organism was E. coli. An empirical antibiotic regimen of ampicillin and gentamicin continues to have an adequate coverage for EOS in our population.

Rhamnetin, a Natural Flavonoid, Ameliorates Organ Damage in a Mouse Model of Carbapenem-Resistant Acinetobacter baumannii-Induced Sepsis.

In sepsis, the persistence of uncontrolled inflammatory response of infected host cells eventually leads to severe lung and organ failure and, ultimately, death. Carbapenem-resistant Acinetobacter baumannii (CRAB), causative bacteria of sepsis and lung failure in acute cases, belongs to a group of critical pathogens that cannot be eradicated using the currently available antibiotics. This underlines the necessity of developing new modes of therapeutics that can control sepsis at the initial stages. In this study, we investigated the anti-inflammatory activities in vitro and in vivo and the antiseptic effects of rhamnetin, a naturally occurring flavonoid. We found that among its isoforms, the potency of rhamnetin was less explored but rhamnetin possessed superior anti-inflammatory activity with least cytotoxicity. Rhamnetin showed significant anti-inflammatory effects in lipopolysaccharide-, CRAB-, and Escherichia coli (E. coli)-stimulated mouse macrophages by inhibiting the release of interleukin-6 and nitric oxide. In a mouse model of sepsis infected with clinically isolated CRAB or E. coli, rhamnetin significantly reduced the bacterial burden in the organs. In addition, normalized pro-inflammatory cytokine levels in lung lysates and histological analysis of lung tissue indicated alleviation of lung damage. This study implies that a potent natural product such as rhamnetin could be a future therapeutic for treating carbapenem-resistant gram-negative sepsis.

The Role of Virulence Factors in Neonatal Sepsis Caused by Enterobacterales: A Systematic Review.

Neonatal sepsis is a life-threatening condition with high mortality. Virulence determinants relevant in causing Gram-negative (GN) neonatal sepsis are still poorly characterized. A better understanding of virulence factors (VFs) associated with GN neonatal sepsis could offer new targets for therapeutic interventions. The aim of this review was to assess the role of GN VFs in neonatal sepsis. We primarily aimed to investigate the main VFs leading to adverse outcome and second to evaluate VFs associated with increased invasiveness/pathogenicity in neonates. MEDLINE, Embase, and Cochrane Library were systematically searched for studies reporting data on the role of virulome/VFs in bloodstream infections caused by Enterobacterales among neonates and infants aged 0–90 days. Twenty studies fulfilled the inclusion criteria. Only 4 studies reported data on the association between pathogen virulence determinants and neonatal mortality, whereas 16 studies were included in the secondary analyses. The quality of reporting was suboptimal in the great majority of the published studies. No consistent association between virulence determinants and GN strains causing neonatal sepsis was identified. Considerable heterogeneity was found in terms of VFs analysed and reported, included population and microbiological methods, with the included studies often showing conflicting data. This variability hampered the comparison of the results. In conclusions, pathogens responsible for neonatal sepsis are widely heterogenous and can use different pathways to develop invasive disease. The recent genome-wide approach needs to include multicentre studies with larger sample sizes, analyses of VF gene profiles instead of single VF genes, alongside a comprehensive collection of clinical information. A better understanding of the roles of virulence genes in neonatal GN bacteraemia may offer new vaccine targets and new markers of highly virulent strains. This information can potentially be used for screening and preventive interventions as well as for new targets for anti-virulence antibiotic-sparing therapies.

UTI-Associated Septic Cardiomyopathy: Saving the Heart in the Nick of Time

A patient with gram-negative sepsis developed acute global biventricular dysfunction with reduced left ventricular ejection fraction. A diagnosis of sepsis-induced cardiomyopathy (SICM) was made following the complete resolution of cardiac dysfunction. This case highlights the importance of the early diagnosis of SICM and treatment of the underlying cause.

Impact of EUCAST rapid antimicrobial susceptibility testing (RAST) on management of Gram-negative bloodstream infection

ObjectivesDuring bloodstream infections, reducing the time to antimicrobial susceptibility testing is crucial to initiation of early appropriate antibiotic therapy. For Gram-negative infections, a phenotypic approach remains necessary. Rapid antimicrobial testing (RAST) is a recently developed phenotypic EUCAST method. The goal of this study was to evaluate the accuracy and clinical impact of RAST. Patients and methodsFrom September 2020 to August 2021, Gram-negative episodes with positive blood culture detected in the morning were included in the RAST group. Categorical agreement of RAST with conventional antimicrobial testing on strains was determined. To assess antibiotic management and patient outcomes, the RAST group was compared with a control group (CG) with positive blood culture detected in the afternoon for which overnight antimicrobial testing was performed. ResultsThe RAST group included 61 episodes from 61 patients, while the CG group included 49 episodes from 48 patients. While RAST performed on 41 E. coli, 11 K. pneumoniae and 9 P. aeruginosa strains highlighted 99.3 % of categorical agreement, 7.4 % of unreadable zones and 9.4 % of technical uncertainty area at 4 h incubation were also reported.For the RAST group, effective antibiotic therapy was prescribed in 100 % of patients on the day of positive blood culture (day 1) vs 88 % in CG (p = 0,007). As for beta-lactams on day 1, RAST led to 9 escalations and 6 de-escalations. Mortality and length of hospital stay did not significantly differ between the two groups. ConclusionRAST improves management of antibiotic therapy in patients with Gram-negative sepsis.