The Plasma Lipidomic Landscape in Patients with Sepsis due to Community-acquired Pneumonia.

Rationale: The plasma lipidome has the potential to reflect many facets of the host status during severe infection. Previous work is limited to specific lipid groups or was focused on lipids as prognosticators.Objectives: To map the plasma lipidome during sepsis due to community-acquired pneumonia (CAP) and determine the disease specificity and associations with clinical features.Methods: We analyzed 1,833 lipid species across 33 classes in 169 patients admitted to the ICU with sepsis due to CAP, 51 noninfected ICU patients, and 48 outpatient controls. In a paired analysis, we reanalyzed patients still in the ICU 4 days after admission (n = 82).Measurements and Main Results: A total of 58% of plasma lipids were significantly lower in patients with CAP-attributable sepsis compared with outpatient controls (6% higher, 36% not different). We found strong lipid class-specific associations with disease severity, validated across two external cohorts, and inflammatory biomarkers, in which triacylglycerols, cholesterol esters, and lysophospholipids exhibited the strongest associations. A total of 36% of lipids increased over time, and stratification by survival revealed diverging lipid recovery, which was confirmed in an external cohort; specifically, a 10% increase in cholesterol ester levels was related to a lower odds ratio (0.84; P = 0.006) for 30-day mortality (absolute mortality, 18 of 82). Comparison with noninfected ICU patients delineated a substantial common illness response (57.5%) and a distinct lipidomic signal for patients with CAP-attributable sepsis (37%).Conclusions: Patients with sepsis due to CAP exhibit a time-dependent and partially disease-specific shift in their plasma lipidome that correlates with disease severity and systemic inflammation and is associated with higher mortality.

Beneficial effects of citrulline enteral administration on sepsis-induced T cell mitochondrial dysfunction.

Severe sepsis induces a sustained immune dysfunction associated with poor clinical behavior. In particular, lymphopenia along with increased lymphocyte apoptosis and decreased lymphocyte proliferation, enhanced circulating regulatory T cells (Treg), and the emergence of myeloid-derived suppressor cells (MDSCs) have all been associated with persistent organ dysfunction, secondary infections, and late mortality. The mechanisms involved in MDSC-mediated T cell dysfunction during sepsis share some features with those described in malignancies such as arginine deprivation. We hypothesized that increasing arginine availability would restore T cell function and decrease sepsis-induced immunosuppression. Using a mouse model of sepsis based on cecal ligation and puncture and secondary pneumonia triggered by methicillin-resistant Staphylococcus aureus inoculation, we demonstrated that citrulline administration was more efficient than arginine in increasing arginine plasma levels and restoring T cell mitochondrial function and proliferation while reducing sepsis-induced Treg and MDSC expansion. Because there is no specific therapeutic strategy to restore immune function after sepsis, we believe that our study provides evidence for developing citrulline-based clinical studies in sepsis.

Kidney Increase Natriuresis but Not Glomerular Filtration Under Veno-venous ECMO, a Retrospective Study.

PURPOSE: Acute kidney injury is a frequent complication of acute respiratory distress syndrome (ARDS). We aim to study the evolution of kidney function in patients presenting severe ARDS and requiring veno-venous extracorporeal membrane oxygenation (VV ECMO). METHODS: We conducted a multicenter retrospective study, including adult patients requiring VV ECMO for ARDS. The primary outcome was the evolution of the serum creatinine level after VV ECMO initiation. Secondary outcomes were change in urine output, and urine biochemical parameters after VV ECMO initiation. RESULTS: One hundred and two patients were included. VV ECMO was initiated after a median of 6 days of mechanical ventilation, mainly for ARDS caused by COVID-19 (73%). Serum creatinine level did not significantly differ after VV ECMO initiation (P = .20). VV ECMO was associated with a significant increase in daily urine output (+6.6 mL/kg/day, [3.8;9.3] P < .001), even after adjustment for potential confounding factors; with an increase in natriuresis. The increase in urine output under VV ECMO was associated with a reduced risk of receiving kidney replacement therapy (OR 0.4 [0.2;0.8], P = .026). CONCLUSIONS: VV ECMO initiation in severe ARDS is associated with an increase in daily urine output and natriuresis, without change in glomerular filtration rate.

Platelet transfusions in adult ICU patients with thrombocytopenia: A sub-study of the PLOT-ICU inception cohort study.

BACKGROUND: Platelet transfusions are frequently used in the intensive care unit (ICU), but current practices including used product types, volumes, doses and effects are unknown. STUDY DESIGN AND METHODS: Sub-study of the inception cohort study 'Thrombocytopenia and Platelet Transfusions in the ICU (PLOT-ICU)', including acutely admitted, adult ICU patients with thrombocytopenia (platelet count <150 × 109/L). The primary outcome was the number of patients receiving platelet transfusion in ICU by product type. Secondary outcomes included platelet transfusion details, platelet increments, bleeding, other transfusions and mortality. RESULTS: Amongst 504 patients with thrombocytopenia from 43 hospitals in 10 countries in Europe and the United States, 20.8% received 565 platelet transfusions; 61.0% received pooled products, 21.9% received apheresis products and 17.1% received both with a median of 2 (interquartile range 1-4) days from admission to first transfusion. The median volume per transfusion was 253 mL (180-308 mL) and pooled products accounted for 59.1% of transfusions, however, this varied across countries. Most centres (73.8%) used fixed dosing (medians ranging from 2.0 to 3.5 × 1011 platelets/transfusion) whilst some (mainly in France) used weight-based dosing (ranging from 0.5 to 0.7 × 1011 platelets per 10 kg body weight). The median platelet count increment for a single prophylactic platelet transfusion was 2 (-1 to 8) × 109/L. Outcomes of patients with thrombocytopenia who did and did not receive platelet transfusions varied. CONCLUSIONS: Among acutely admitted, adult ICU patients with thrombocytopenia, 20.8% received platelet transfusions in ICU of whom most received pooled products, but considerable variation was observed in product type, volumes and doses across countries. Prophylactic platelet transfusions were associated with limited increases in platelet counts.

Blood leukocyte transcriptomes in Gram-positive and Gram-negative community-acquired pneumonia.

BACKGROUND: Gram-positive and Gram-negative bacteria are the most common causative pathogens in community-acquired pneumonia (CAP) on the intensive care unit (ICU). The aim of this study was to determine whether the host immune response differs between Gram-positive and Gram-negative CAP upon ICU admission. METHODS: 16 host response biomarkers providing insight into pathophysiological mechanisms implicated in sepsis and blood leukocyte transcriptomes were analysed in patients with CAP upon ICU admission in two tertiary hospitals in the Netherlands. RESULTS: 309 patients with CAP with a definite or probable likelihood (determined by predefined criteria) were included. A causative pathogen was determined in 74.4% of admissions. Patients admitted with Gram-positive CAP (n=90) were not different from those admitted with Gram-negative CAP (n=75) regarding demographics, chronic comorbidities, severity of disease and mortality. Host response biomarkers reflective of systemic inflammation, coagulation activation and endothelial cell function, as well as blood leukocyte transcriptomes, were largely similar between Gram-positive and Gram-negative CAP. Blood leukocyte transcriptomes were also similar in Gram-positive and Gram-negative CAP in two independent validation cohorts. On a pathogen-specific level, Streptococcus pneumoniae and Escherichia coli induced the most distinct host immune response. CONCLUSION: Outcome and host response are similar in critically ill patients with CAP due to Gram-positive bacteria compared with Gram-negative bacteria.

Effect of erythromycin on mortality and the host response in critically ill patients with sepsis: a target trial emulation.

BACKGROUND: Immunomodulatory therapies that improve the outcome of sepsis are not available. We sought to determine whether treatment of critically ill patients with sepsis with low-dose erythromycin-a macrolide antibiotic with broad immunomodulatory effects-decreased mortality and ameliorated underlying disease pathophysiology. METHODS: We conducted a target trial emulation, comparing patients with sepsis admitted to two intensive care units (ICU) in the Netherlands for at least 72 h, who were either exposed or not exposed during this period to treatment with low-dose erythromycin (up to 600 mg per day, administered as a prokinetic agent) but no other macrolides. We used two common propensity score methods (matching and inverse probability of treatment weighting) to deal with confounding by indication and subsequently used Cox regression models to estimate the treatment effect on the primary outcome of mortality rate up to day 90. Secondary clinical outcomes included change in SOFA, duration of mechanical ventilation and the incidence of ICU-acquired infections. We used linear mixed models to assess differences in 15 host response biomarkers reflective of key pathophysiological processes from admission to day 4. RESULTS: In total, 235 patients started low-dose erythromycin treatment, 470 patients served as controls. Treatment started at a median of 38 [IQR 25-52] hours after ICU admission for a median of 5 [IQR 3-8] total doses in the first course. Matching and weighting resulted in populations well balanced for proposed confounders. We found no differences between patients treated with low-dose erythromycin and control subjects in mortality rate up to day 90: matching HR 0.89 (95% CI 0.64-1.24), weighting HR 0.95 (95% CI 0.66-1.36). There were no differences in secondary clinical outcomes. The change in host response biomarker levels from admission to day 4 was similar between erythromycin-treated and control subjects. CONCLUSION: In this target trial emulation in critically ill patients with sepsis, we could not demonstrate an effect of treatment with low-dose erythromycin on mortality, secondary clinical outcomes or host response biomarkers.

Association between age and the host response in critically ill patients with sepsis.

BACKGROUND: The association of ageing with increased sepsis mortality is well established. Nonetheless, current investigations on the influence of age on host response aberrations are largely limited to plasma cytokine levels while neglecting other pathophysiological sepsis domains like endothelial cell activation and function, and coagulation activation. The primary objective of this study was to gain insight into the association of ageing with aberrations in key host response pathways and blood transcriptomes in sepsis. METHODS: We analysed the clinical outcome (n = 1952), 16 plasma biomarkers providing insight in deregulation of specific pathophysiological domains (n = 899), and blood leukocyte transcriptomes (n = 488) of sepsis patients stratified according to age decades. Blood transcriptome results were validated in an independent sepsis cohort and compared with healthy individuals. RESULTS: Older age was associated with increased mortality independent of comorbidities and disease severity. Ageing was associated with lower endothelial cell activation and dysfunction, and similar inflammation and coagulation activation, despite higher disease severity scores. Blood leukocytes of patients ≥ 70 years, compared to patients < 50 years, showed decreased expression of genes involved in cytokine signaling, and innate and adaptive immunity, and increased expression of genes involved in hemostasis and endothelial cell activation. The diminished expression of gene pathways related to innate immunity and cytokine signaling in subjects ≥ 70 years was sepsis-induced, as healthy subjects ≥ 70 years showed enhanced expression of these pathways compared to healthy individuals < 50 years. CONCLUSIONS: This study provides novel evidence that older age is associated with relatively mitigated sepsis-induced endothelial cell activation and dysfunction, and a blood leukocyte transcriptome signature indicating impaired innate immune and cytokine signaling. These data suggest that age should be considered in patient selection in future sepsis trials targeting the immune system and/or the endothelial cell response.

Plasma Ferritin as Marker of Macrophage Activation-Like Syndrome in Critically Ill Patients With Community-Acquired Pneumonia.

OBJECTIVES: Plasma ferritin levels above 4,420 ng/mL have been proposed as a diagnostic marker for macrophage activation-like syndrome in sepsis and used for selection of sepsis patients for anti-inflammatory therapy. We here sought to determine the frequency, presentation, outcome, and host response aberrations of macrophage activation-like syndrome, as defined by admission ferritin levels above 4,420 ng/mL, in critically ill patients with community-acquired pneumonia. DESIGN: A prospective observational cohort study. SETTING: ICUs in two tertiary hospitals in the Netherlands. PATIENTS: One hundred fifty-three patients admitted with community-acquired pneumonia. MEASUREMENTS AND MAIN RESULTS: Patients were stratified in community-acquired pneumonia-macrophage activation-like syndrome (n = 15; 9.8%) and community-acquired pneumonia-control groups (n = 138; 90.2%) based on an admission plasma ferritin level above or below 4,420 ng/mL, respectively. Community-acquired pneumonia-macrophage activation-like syndrome patients presented with a higher disease severity and had a higher ICU mortality (46.7% vs 12.3% in community-acquired pneumonia-controls; p = 0.002). Twenty-three plasma biomarkers indicative of dysregulation of key host response pathways implicated in sepsis pathogenesis (systemic inflammation, cytokine responses, endothelial cell activation, and barrier function, coagulation activation) were more disturbed in community-acquired pneumonia-macrophage activation-like syndrome patients. Hematologic malignancies were overrepresented in community-acquired pneumonia-macrophage activation-like syndrome patients (33.3% vs 5.1% in community-acquired pneumonia-controls; p = 0.001). In a subgroup analysis excluding patients with hematologic malignancies (n = 141), differences in mortality were not present anymore, but the exaggerated host response abnormalities in community-acquired pneumonia-macrophage activation-like syndrome patients remained. CONCLUSIONS: Macrophage activation-like syndrome in critically ill patients with community-acquired pneumonia occurs more often in patients with hematologic malignancies and is associated with deregulation of multiple host response pathways.

Venoarterial extracorporeal membrane oxygenation induces early immune alterations.

BACKGROUND: Venoarterial extracorporeal membrane oxygenation (VA-ECMO) provides heart mechanical support in critically ill patients with cardiogenic shock. Despite important progresses in the management of patients under VA-ECMO, acquired infections remain extremely frequent and increase mortality rate. Since immune dysfunctions have been described in both critically ill patients and after surgery with cardiopulmonary bypass, VA-ECMO initiation may be responsible for immune alterations that may expose patients to nosocomial infections (NI). Therefore, in this prospective study, we aimed to study immune alterations induced within the first days by VA-ECMO initiation. METHODS: We studied immune alterations induced by VA-ECMO initiation using cytometry analysis to characterize immune cell changes and enzyme-linked immunosorbent assay (ELISA) to explore plasma cytokine levels. To analyze specific changes induced by VA-ECMO initiation, nine patients under VA-ECMO (VA-ECMO patients) were compared to nine patients with cardiogenic shock (control patients). RESULTS: Baseline immune parameters were similar between the two groups. VA-ECMO was associated with a significant increase in circulating immature neutrophils with a significant decrease in C5a receptor expression. Furthermore, we found that VA-ECMO initiation was followed by lymphocyte dysfunction along with myeloid-derived suppressor cells (MDSC) expansion. ELISA analysis revealed that VA-ECMO initiation was followed by an increase in pro-inflammatory cytokines such as IL-6, IL-8 and TNF-α along with IL-10, a highly immunosuppressive cytokine. CONCLUSION: VA-ECMO is associated with early immune changes that may be responsible for innate and adaptive immune alterations that could confer an increased risk of infection.

Elevated trefoil factor 3 plasma levels in critically ill patients with abdominal sepsis or non-infectious abdominal illness.

Trefoil factor 3 (TFF3) is a small peptide secreted mainly by goblet cells in the gut, where it plays a key role in gastrointestinal defence and repair. Plasma TFF3 has been reported as a biomarker of intestinal injury and as such it has been evaluated as a marker of disease activity in colitis. Impaired gut barrier function has been postulated as the "motor" of critical illness. We here sought to determine the temporal dynamics of plasma TFF3 in adult patients admitted to intensive care unit with abdominal sepsis or after major abdominal surgery for a non-infectious condition (post-op GI patients). TFF3 was measured in plasma obtained from 143 patients with abdominal sepsis and 98 post-op GI patients on admission to the intensive care (day 0) and at days 2 and 4 thereafter. Abdominal sepsis patients showed sustained elevated plasma TFF3 levels from day 0 to 4 relative to healthy control values, while in post-op GI patients admission TFF3 levels were not increased, only rising at day 2 and 4. In both patient groups, the presence of shock was associated with higher TFF3 levels. Moreover, patients with 3 or more organs failing had higher plasma TFF3 concentrations. While plasma TFF3 was higher in sepsis patients who did not survive until day 30, TFF3 levels were not independently associated with 30-day mortality in a Cox regression analysis. These results could support the theory that intestinal injury contributes to the pathogenesis of critical illness. Future studies are needed to elucidate whether the proposed gut dysfunction precedes or supersedes organ dysfunction in time.

Impaired efferocytosis and neutrophil extracellular trap clearance by macrophages in ARDS.

Exaggerated release of neutrophil extracellular traps (NETs) along with decreased NET clearance and inability to remove apoptotic cells (efferocytosis) may contribute to sustained inflammation in acute respiratory distress syndrome (ARDS). Recent studies in experimental models of ARDS have revealed the crosstalk between AMP-activated protein kinase (AMPK) and high-mobility group box 1 (HMGB1), which may contribute to effectiveness of efferocytosis, thereby reducing inflammation and ARDS severity.We investigated neutrophil and NET clearance by macrophages from control and ARDS patients and examined how bronchoalveolar lavage (BAL) fluid from control and ARDS patients could affect NET formation and efferocytosis. Metformin (an AMPK activator) and neutralising antibody against HMGB1 were applied to improve efferocytosis and NET clearance.Neutrophils from ARDS patients showed significantly reduced apoptosis. Conversely, NET formation was significantly enhanced in ARDS patients. Exposure of neutrophils to ARDS BAL fluid promoted NET production, while control BAL fluid had no effect. Macrophage engulfment of NETs and apoptotic neutrophils was diminished in ARDS patients. Notably, activation of AMPK in macrophages or neutralisation of HMGB1 in BAL fluid improved efferocytosis and NET clearance.In conclusion, restoration of AMPK activity with metformin or specific neutralisation of HMGB1 in BAL fluid represent promising therapeutic strategies to decrease sustained lung inflammation during ARDS.

T-cell defect in diffuse large B-cell lymphomas involves expansion of myeloid-derived suppressor cells.

In diffuse large B-cell lymphoma (DLBCL), the number of circulating monocytes and neutrophils represents an independent prognostic factor. These cell subsets include monocytic and granulocytic myeloid-derived suppressor cells (M- and G-MDSCs) defined by their ability to suppress T-cell responses. MDSCs are a heterogeneous population described in inflammatory and infectious diseases and in numerous tumors including multiple myeloma, chronic lymphocytic leukemia, and DLBCL. However, their mechanisms of action remain unclear. We broadly assessed the presence and mechanisms of suppression of MDSC subsets in DLBCL. First, a myeloid suppressive signature was identified by gene expression profiling in DLBCL peripheral blood. Accordingly, we identified, in a cohort of 66 DLBCL patients, an increase in circulating G-MDSC (Lin(neg)HLA-DR(neg)CD33(pos)CD11b(pos)) and M-MDSC (CD14(pos)HLA-DR(low)) counts. Interestingly, only M-MDSC number was correlated with the International Prognostic Index, event-free survival, and number of circulating Tregs. Furthermore, T-cell proliferation was restored after monocyte depletion. Myeloid-dependent T-cell suppression was attributed to a release of interleukin-10 and S100A12 and increased PD-L1 expression. In summary, we identified expanded MDSC subsets in DLBCL, as well as new mechanisms of immunosuppression in DLBCL.

Early Expansion of Circulating Granulocytic Myeloid-derived Suppressor Cells Predicts Development of Nosocomial Infections in Patients with Sepsis.

RATIONALE: Sepsis induces a sustained immune dysfunction responsible for poor outcome and nosocomial infections. Myeloid-derived suppressor cells (MDSCs) described in cancer and inflammatory processes may be involved in sepsis-induced immune suppression, but their clinical impact remains poorly defined. OBJECTIVES: To clarify phenotype, suppressive activity, origin, and clinical impact of MDSCs in patients with sepsis. METHODS: Peripheral blood transcriptomic analysis was performed on 29 patients with sepsis and 15 healthy donors. A second cohort of 94 consecutive patients with sepsis, 11 severity-matched intensive care patients, and 67 healthy donors was prospectively enrolled for flow cytometry and functional experiments. MEASUREMENTS AND MAIN RESULTS: Genes involved in MDSC suppressive functions, including S100A12, S100A9, MMP8, and ARG1, were up-regulated in the peripheral blood of patients with sepsis. CD14posHLA-DRlow/neg monocytic (M)-MDSCs were expanded in intensive care unit patients with and without sepsis and CD14negCD15pos low-density granulocytes/granulocytic (G)-MDSCs were more specifically expanded in patients with sepsis (P < 0.001). Plasma levels of MDSC mediators S100A8/A9, S100A12, and arginase 1 were significantly increased. In vitro, CD14pos- and CD15pos-cell depletion increased T-cell proliferation in patients with sepsis. G-MDSCs, made of immature and mature granulocytes expressing high levels of degranulation markers, were specifically responsible for arginase 1 activity. High initial levels of G-MDSCs, arginase 1, and S100A12 but not M-MDSCs were associated with subsequent occurrence of nosocomial infections. CONCLUSIONS: M-MDSCs and G-MDSCs strongly contribute to T-cell dysfunction in patients with sepsis. More specifically, G-MDSCs producing arginase 1 are associated with a higher incidence of nosocomial infections and seem to be major actors of sepsis-induced immune suppression.

DC-SIGN-expressing macrophages trigger activation of mannosylated IgM B-cell receptor in follicular lymphoma.

Follicular lymphoma (FL) results from the accumulation of malignant germinal center (GC) B cells leading to the development of an indolent and largely incurable disease. FL cells remain highly dependent on B-cell receptor (BCR) signaling and on a specific cell microenvironment, including T cells, macrophages, and stromal cells. Importantly, FL BCR is characterized by a selective pressure to retain surface immunoglobulin M (IgM) BCR despite an active class-switch recombination process, and by the introduction, in BCR variable regions, of N-glycosylation acceptor sites harboring unusual high-mannose oligosaccharides. However, the relevance of these 2 FL BCR features for lymphomagenesis remains unclear. In this study, we demonstrated that IgM(+) FL B cells activated a stronger BCR signaling network than IgG(+) FL B cells and normal GC B cells. BCR expression level and phosphatase activity could both contribute to such heterogeneity. Moreover, we underlined that a subset of IgM(+) FL samples, displaying highly mannosylated BCR, efficiently bound dendritic cell-specific intercellular adhesion molecule-3-grabbing nonintegrin (DC-SIGN), which could in turn trigger delayed but long-lasting BCR aggregation and activation. Interestingly, DC-SIGN was found within the FL cell niche in situ. Finally, M2 macrophages induced a DC-SIGN-dependent adhesion of highly mannosylated IgM(+) FL B cells and triggered BCR-associated kinase activation. Interestingly, pharmacologic BCR inhibitors abolished such crosstalk between macrophages and FL B cells. Altogether, our data support an important role for DC-SIGN-expressing infiltrating cells in the biology of FL and suggest that they could represent interesting therapeutic targets.

At-risk drinking is independently associated with ICU and one-year mortality in critically ill nontrauma patients*.

OBJECTIVES: The impact of at-risk drinking on the outcomes of nontrauma patients is not well characterized. The aim of this study was to determine whether at-risk drinking is independently associated with the survival of nontrauma patients in an ICU and within 1 year following ICU discharge. DESIGN: Observational cohort study. SETTING: A 21-bed mixed ICU in a university hospital. PATIENTS: A total of 662 patients who experienced an ICU stay of 3 days or more and for whom alcohol consumption could be assessed. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: ICU-related variables were collected prospectively, and a 1-year follow-up was determined retrospectively. Analyses were adjusted based on prognostic determinants of short- and long-term outcomes, as previously described in ICU patients and alcohol abusers. Two hundred and eight patients (33%) were identified as at-risk drinkers according to the National Institute on Alcohol Abuse and Alcoholism criteria. Additionally, 111 patients (17%) died in the ICU, and 97 (15%) died after ICU discharge. From the ICU admission until the end of the 1-year follow-up period, the at-risk drinkers exhibited poorer survival than the non-at-risk drinkers (p = 0.0004, as determined by the log-rank test). More specifically, 50 at-risk drinkers (24%) versus 61 non-at-risk drinkers (13%) died in the ICU (p = 0.0009 for the comparison). After adjustment, at-risk drinking remained independently associated with mortality in the ICU (adjusted odds ratio of 1.83; 95% CI of 1.16-2.89; p = 0.01) and with mortality within the year following ICU discharge (adjusted hazard ratio of 1.70; 95% CI of 1.15-2.52; p = 0.008). The causes of death in the at-risk and non-at-risk drinkers were similar. CONCLUSIONS: In this population of critically ill nontrauma patients, at-risk drinking was independently associated with death in the ICU and within the year following ICU discharge.

Short-term decline in all-cause acquired infections with the routine use of a decontamination regimen combining topical polymyxin, tobramycin, and amphotericin B with mupirocin and chlorhexidine in the ICU: a single-center experience.

OBJECTIVES: In a multicenter, placebo-controlled, randomized, double-blind trial, we showed that acquired infections in intubated patients were reduced by the combination of topical polymyxin plus tobramycin and nasal mupirocin plus chlorhexidine body wash. Because intubated patients are particularly at risk for acquired infections, we reassessed the impact of this protocol as a routine procedure to control acquired infections in the ICU. DESIGN: Nonrandomized study comparing acquired infections in ICU patients during two 1-year periods: the last year before (group A, n = 925) and the first year after the implementation of the protocol (group B, n = 1,022). Acquired infections were prospectively recorded. SETTING: Polyvalent medical ICU at a university-affiliated hospital. PATIENTS: All patients admitted to the ICU. INTERVENTIONS: Administration of polymyxin/tobramycin/amphotericin B in the oropharynx and the gastric tube plus a mupirocin/chlorhexidine regimen in intubated patients and standard care in the other patients. MEASUREMENTS AND MAIN RESULTS: The comparison of acquired infection rates between groups was adjusted for differences at baseline. Infection rates were lower in group B compared with group A (5.3% vs 11.0%; p < 0.001), as were the incidence rates of total acquired infections (9.4 vs 23.6 per 1,000 patient-days; p < 0.001), intubation-related pneumonia (5.1 vs 17.1 per 1,000 ventilator-days; p < 0.001), and catheter-related bloodstream infections (1.0 vs 3.5 per 1,000 catheter-days; p = 0.03). There were fewer acquired infections caused by ceftazidime-resistant Enterobacteriaceae (0.8‰ vs 3.6‰; p < 0.001), ciprofloxacin-resistant Enterobacteriaceae (0.8‰ vs 2.5‰; p = 0.02), ciprofloxacin-resistant Pseudomonas aeruginosa (0.5‰ vs 1.6‰; p = 0.05), and colistin-resistant Gram-negative bacilli (0.7‰ vs 1.9‰; p = 0.04). Fewer patients got acquired infections due to multidrug-resistant aerobic Gram-negative bacilli (p = 0.008). CONCLUSIONS: In intubated patients, the use of topical polymyxin/tobramycin/amphotericin B plus mupirocin/chlorhexidine was associated with the reduction of all-cause ICU-acquired infections. Long-term emergence of multidrug-resistant organisms deserves further investigation.