Carbapenems are considered as last-resort antibiotics for the treatment of infections caused by multidrug-resistant Gram-negative bacteria. With the increasing use of carbapenems in clinical practice, the emergence of carbapenem-resistant pathogens now poses a great threat to human health. Currently, antibiotic options for the treatment of carbapenem-resistant Enterobacteriaceae (CRE) are very limited, with polymyxins, tigecycline, fosfomycin, and aminoglycosides as the mainstays of therapy. The need for new and effective anti-CRE therapies is urgent. Here, we describe the current understanding of issues related to CRE and review combination therapeutic strategies for CRE infections, including high-dose tigecycline, high-dose prolonged-infusion of carbapenem, and double carbapenem therapy. We also review the newly available antibiotics which have potential in the future treatment of CRE infections: ceftazidime/avibactam, which is active against KPC and OXA-48 producers; meropenem/vaborbactam, which is active against KPC producers; plazomicin, which is a next-generation aminoglycoside with in vitro activity against CRE; and eravacycline, which is a tetracycline class antibacterial with in vitro activity against CRE. Although direct evidence for CRE treatment is still lacking and the development of resistance is a concern, these new antibiotics provide additional therapeutic options for CRE infections. Finally, we review other potential anti-CRE antibiotics in development: imipenem/relebactam and cefiderocol. Currently, high-dose and combination strategies that may include the new β-lactam/β-lactamase inhibitors should be considered in severe CRE infections to maximize treatment success. In the future, when more treatment options are available, therapy for CRE infections should be individualized and based on molecular phenotypes of resistance, susceptibility profiles, disease severity, and patient characteristics. More high-quality studies are needed to guide effective treatment for infections caused by CRE.

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A RDS, the more severe form of acute lung injury (ALI), is a common and lethal disease in ICUs worldwide. Clinically, ARDS is characterized by acute respiratory failure with severe hypoxemia and diffuse pulmonary infi ltrates. Despite recent advances in critical care and signifi cant efforts invested in the basic research and clinical trials of ARDS, its mortality rate (35%-45%) has remained relatively unchanged since 1994. 1 ARDS usually develops in patients with predisposing conditions that induce systemic infl ammatory response, such as sepsis, pneumonia, major trauma, multiple transfusions, aspiration, and acute pancreatitis, among which sepsis is the most common cause of ARDS. [2][3][4][5] In a large prospective cohort study, severe sepsis with a suspected pulmonary source (46%) or a nonpulmonary source (33%) was the most common risk factor for ALI. 6 On the other hand, only Background: ARDS may occur after either septic or nonseptic injuries. Sepsis is the major cause of ARDS, but little is known about the differences between sepsis-related and non-sepsis-related ARDS. Methods: A total of 2,786 patients with ARDS-predisposing conditions were enrolled consecutively into a prospective cohort, of which 736 patients developed ARDS. We defi ned sepsis-related ARDS as ARDS developing in patients with sepsis and non-sepsis-related ARDS as ARDS developing after nonseptic injuries, such as trauma, aspiration, and multiple transfusions. Patients with both septic and nonseptic risks were excluded from analysis. Results: Compared with patients with non-sepsis-related ARDS (n 5 62), patients with sepsisrelated ARDS (n 5 524) were more likely to be women and to have diabetes, less likely to have preceding surgery, and had longer pre-ICU hospital stays and higher APACHE III (Acute Physiology and Chronic Health Evaluation III) scores (median, 78 vs 65, P , .0001). There were no differences in lung injury score, blood pH, Pa O 2 /F IO 2 ratio, and Pa CO 2 on ARDS diagnosis. However, patients with sepsis-related ARDS had signifi cantly lower Pa O 2 /F IO 2 ratios than patients with nonsepsis-related ARDS patients on ARDS day 3 ( P 5 .018), day 7 ( P 5 .004), and day 14 ( P 5 .004) (repeated-measures analysis, P 5 .011). Compared with patients with non-sepsis-related ARDS, those with sepsis-related had a higher 60-day mortality (38.2% vs 22.6%; P 5 .016), a lower successful extubation rate (53.6% vs 72.6%; P 5 .005), and fewer ICU-free days ( P 5 .0001) and ventilatorfree days ( P 5 .003). In multivariate analysis, age, APACHE III score, liver cirrhosis, metastatic cancer, admission serum bilirubin and glucose levels, and treatment with activated protein C were independently associated with 60-day ARDS mortality. After adjustment, sepsis-related ARDS was no longer associated with higher 60-day mortality (hazard ratio, 1.26; 95% CI, 0.71-2.22). Conclusion: Sepsis-related ARDS has a higher overall disease severity, poorer recovery from lung injury, lower successful extubation rate, and higher mortality than non-sepsis-related ...

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The A/H1N1 influenza strain isolated in Mexico in 2009 caused severe pulmonary illness in a small number of exposed individuals. Our objective was to determine the influence of genetic factors on their susceptibility. We carried out a case–control association study genotyping 91 patients with confirmed severe pneumonia from A/H1N1 infection and 98 exposed but asymptomatic household contacts, using the HumanCVD BeadChip (Illumina, San Diego, CA, USA). Four risk single-nucleotide polymorphisms were significantly (p<0.0001) associated with severe pneumonia: rs1801274 (Fc fragment of immunoglobulin G, low-affinity IIA, receptor (FCGR2A) gene, chromosome 1; OR 2.68, 95% CI 1.69–4.25); rs9856661 (gene unknown, chromosome 3; OR 2.62, 95% CI 1.64–4.18); rs8070740 (RPA interacting protein (RPAIN) gene, chromosome 17; OR 2.67, 95% CI 1.63–4.39); and rs3786054 (complement component 1, q subcomponent binding protein (C1QBP) gene, chromosome 17; OR 3.13, 95% CI 1.89–5.17). All SNP associations remained significant after adjustment for sex and comorbidities. The SNPs on chromosome 17 were in linkage disequilibrium. These findings revealed that gene polymorphisms located in chromosomes 1 and 17 might influence susceptibility to development of severe pneumonia in A/H1N1 infection. Two of these SNPs are mapped within genes (FCGR2A, C1QBP) involved in the handling of immune complexes and complement activation, respectively, suggesting that these genes may confer risk due to increased activation of host immunity.

ObjectivesCurrent mortality prediction models used in the intensive care unit (ICU) have a limited role for specific diseases such as influenza, and we aimed to establish an explainable machine learning (ML) model for predicting mortality in critically ill influenza patients using a real-world severe influenza data set.Study designA cross-sectional retrospective multicentre study in TaiwanSettingEight medical centres in Taiwan.ParticipantsA total of 336 patients requiring ICU-admission for virology-proven influenza at eight hospitals during an influenza epidemic between October 2015 and March 2016.Primary and secondary outcome measuresWe employed extreme gradient boosting (XGBoost) to establish the prediction model, compared the performance with logistic regression (LR) and random forest (RF), demonstrated the feature importance categorised by clinical domains, and used SHapley Additive exPlanations (SHAP) for visualised interpretation.ResultsThe data set contained 76 features of the 336 patients with severe influenza. The severity was apparently high, as shown by the high Acute Physiology and Chronic Health Evaluation II score (22, 17 to 29) and pneumonia severity index score (118, 88 to 151). XGBoost model (area under the curve (AUC): 0.842; 95% CI 0.749 to 0.928) outperformed RF (AUC: 0.809; 95% CI 0.629 to 0.891) and LR (AUC: 0.701; 95% CI 0.573 to 0.825) for predicting 30-day mortality. To give clinicians an intuitive understanding of feature exploitation, we stratified features by the clinical domain. The cumulative feature importance in the fluid balance domain, ventilation domain, laboratory data domain, demographic and symptom domain, management domain and severity score domain was 0.253, 0.113, 0.177, 0.140, 0.152 and 0.165, respectively. We further used SHAP plots to illustrate associations between features and 30-day mortality in critically ill influenza patients.ConclusionsWe used a real-world data set and applied an ML approach, mainly XGBoost, to establish a practical and explainable mortality prediction model in critically ill influenza patients.

Background: Hyperbilirubinaemia is a common complication of sepsis. Elevated bilirubin may induce inflammation and apoptosis. It was hypothesised that increased serum bilirubin on Intensive Care Unit (ICU) admission contributes to sepsis-related acute respiratory distress syndrome (ARDS). Methods: Serum bilirubin on ICU admission was measured in 1006 patients with sepsis. Serial serum bilirubin was analysed prospectively in patients with sepsis who had ARDS for a period of 28 days. The effects of clinical factors and variants of the UGT1A1 gene on serum bilirubin levels were determined. Outcomes were ARDS risk and mortality. Results: During 60-day follow-up, 326 patients with sepsis developed ARDS, of whom 144 died from ARDS. The hyperbilirubinaemia (>2.0 mg/dl) rate in patients with ARDS (22.4%) was higher than in those without ARDS (14.1%, p = 0.002). For each 1.0 mg/dl increase in admission bilirubin, ARDS risk and 28-and 60-day ARDS mortalities were increased by 7% (OR = 1.07; p = 0.003), 20% (OR = 1.20; p = 0.002) and 18% (OR = 1.18; p = 0.004), respectively. Compared with subjects with bilirubin levels ,2.0 mg/dl, patients with hyperbilirubinaemia had higher risks of ARDS (OR = 2.12; p = 0.0007) and 28-day (OR = 2.24; p = 0.020) and 60-day ARDS mortalities (OR = 2.09; p = 0.020). In sepsisrelated ARDS, serial bilirubin levels in non-survivors were consistently higher than in survivors (p,0.0001). Clinical variables explained 29.5% of the interindividual variation in bilirubin levels, whereas genetic variants of UGT1A1 contributed 7.5%. Conclusion: In sepsis, a higher serum bilirubin level on ICU admission is associated with subsequent ARDS development and mortality.

Rationale: Acute respiratory distress syndrome (ARDS) behaves as a complex genetic trait, yet knowledge of genetic susceptibility factors remains incomplete. Objectives: To identify genetic risk variants for ARDS using large scale genotyping. Methods: A multistage genetic association study was conducted of three critically ill populations phenotyped for ARDS. Stage I, a trauma cohort study (n ¼ 224), was genotyped with a 50K gene-centric single-nucleotide polymorphism (SNP) array. We tested SNPs associated with ARDS at P , 5 3 10 24 for replication in stage II, a trauma case-control population (n ¼ 778). SNPs replicating their association in stage II (P , 0.005) were tested in a stage III nested case-control population of mixed subjects in the intensive care unit (n ¼ 2,063). Logistic regression was used to adjust for potential clinical confounders. We performed ELISA to test for an association between ARDSassociated genotype and plasma protein levels. Measurements and Main Results: A total of 12 SNPs met the stage I threshold for an association with ARDS. rs315952 in the IL1RN gene encoding IL-1 receptor antagonist (IL1RA) replicated its association with reduced ARDS risk in stages II (P , 0.004) and III (P , 0.02), and was robust to clinical adjustment (combined odds ratio ¼ 0.81; P ¼ 4.2 3 10 25 ). Plasma IL1RA level was associated with rs315952C in a subset of critically ill subjects. The effect of rs315952 was independent from the tandem repeat variant in IL1RN. Conclusions: The IL1RN SNP rs315952C is associated with decreased risk of ARDS in three populations with heterogeneous ARDS risk factors, and with increased plasma IL1RA response. IL1RA may attenuate ARDS risk.Keywords: functional genetic polymorphism; acute lung injury; acute respiratory distress syndrome; IL-1 receptor antagonist; replication Acute respiratory distress syndrome (ARDS) is a syndrome characterized by acute bilateral alveolar flooding and severe hypoxemia in the absence of clinical heart failure (1, 2). ARDS afflicts an estimated 190,000 people annually in the United States, and carries a mortality of between 30 and 40% (3). The syndrome can emerge after a variety of potential inciting events, such as sepsis, pneumonia, aspiration, and trauma. However, the risk of ARDS after potential at-risk injuries is not uniform; it appears that individual genetic variation contributes to a patient's susceptibility to ARDS (4, 5). The pathophysiology underlying ARDS remains imprecisely understood, but dysregulated inflammation and altered permeability of the alveolocapillary membrane seem Supported by National Institutes of Health (NIH) grants to fund the study populations, Hospital of the University of Pennsylvania (HL060290, HL079063), Harborview (GM066946), and Massachusetts General Hospital (HL060710). Additional NIH grants RC2HL101770, HL081619, HL090021, and HL102254 supported the genetic and molecular investigations described herein. The genetic determinants of acute respiratory distress syndrome (ARDS) susceptibility remain incompletely u...