Systemic immune activation profiles in streptococcal necrotizing soft tissue infections: A prospective multicenter study.

OBJECTIVE: Early stages with streptococcal necrotizing soft tissue infections (NSTIs) are often difficult to discern from cellulitis. Increased insight into inflammatory responses in streptococcal disease may guide correct interventions and discovery of novel diagnostic targets. METHODS: Plasma levels of 37 mediators, leucocytes and CRP from 102 patients with ß-hemolytic streptococcal NSTI derived from a prospective Scandinavian multicentre study were compared to those of 23 cases of streptococcal cellulitis. Hierarchical cluster analyses were also performed. RESULTS: Differences in mediator levels between NSTI and cellulitis cases were revealed, in particular for IL-1ß, TNFα and CXCL8 (AUC >0.90). Across streptococcal NSTI etiologies, eight biomarkers separated cases with septic shock from those without, and four mediators predicted a severe outcome. CONCLUSION: Several inflammatory mediators and wider profiles were identified as potential biomarkers of NSTI. Associations of biomarker levels to type of infection and outcomes may be utilized to improve patient care and outcomes.

Discriminatory plasma biomarkers predict specific clinical phenotypes of necrotizing soft-tissue infections.

BACKGROUNDNecrotizing soft-tissue infections (NSTIs) are rapidly progressing infections frequently complicated by septic shock and associated with high mortality. Early diagnosis is critical for patient outcome, but challenging due to vague initial symptoms. Here, we identified predictive biomarkers for NSTI clinical phenotypes and outcomes using a prospective multicenter NSTI patient cohort.METHODSLuminex multiplex assays were used to assess 36 soluble factors in plasma from NSTI patients with positive microbiological cultures (n = 251 and n = 60 in the discovery and validation cohorts, respectively). Control groups for comparative analyses included surgical controls (n = 20), non-NSTI controls (i.e., suspected NSTI with no necrosis detected upon exploratory surgery, n = 20), and sepsis patients (n = 24).RESULTSThrombomodulin was identified as a unique biomarker for detection of NSTI (AUC, 0.95). A distinct profile discriminating mono- (type II) versus polymicrobial (type I) NSTI types was identified based on differential expression of IL-2, IL-10, IL-22, CXCL10, Fas-ligand, and MMP9 (AUC >0.7). While each NSTI type displayed a distinct array of biomarkers predicting septic shock, granulocyte CSF (G-CSF), S100A8, and IL-6 were shared by both types (AUC >0.78). Finally, differential connectivity analysis revealed distinctive networks associated with specific clinical phenotypes.CONCLUSIONSThis study identifies predictive biomarkers for NSTI clinical phenotypes of potential value for diagnostic, prognostic, and therapeutic approaches in NSTIs.TRIAL REGISTRATIONClinicalTrials.gov NCT01790698.FUNDINGCenter for Innovative Medicine (CIMED); Region Stockholm; Swedish Research Council; European Union; Vinnova; Innovation Fund Denmark; Research Council of Norway; Netherlands Organisation for Health Research and Development; DLR Federal Ministry of Education and Research; and Swedish Children's Cancer Foundation.

Effect of immunoglobulin G on cytokine response in necrotising soft-tissue infection: A post hoc analysis.

BACKGROUND: A marked inflammatory response in necrotising soft-tissue infection (NSTI) may contribute to the severe clinical course. Intravenous polyspecific immunoglobulin G (IVIG) is used by some as adjuvant treatment for NSTI, but in the randomised INSTINCT trial, no effect of IVIG in NSTI patients was seen on physical quality of life. In experimental studies, IVIG may induce immunosuppressive effects by reducing the pro-inflammatory response and neutralising circulating superantigens. However, data on the potential immunomodulatory effects are sparse and remain to be investigated in a clinical setting. In this post hoc analysis of the INSTINCT trial, we aimed to assess the effect of IVIG on various inflammatory cytokines up to day 3 after randomisation. METHODS: Tumour necrosis factor (TNF), interleukin-1ß, interleukin-6, interleukin-10 and granulocyte colony-stimulating factor were measured at admission, days 1, 2 and 3. RESULTS: A total of 100 ICU patients with NSTI were included; 50 were allocated to IVIG (25 g/d for 3 days) and 50 to placebo. No difference in the overall inflammatory response was observed between groups except from TNF, which was higher in the IVIG group as compared to the placebo group (area under curve-admission to day 3, 93.6 vs 60.2, P = .02). Similarly, no differences were observed in percentage change from baseline to day 3 in any of the studied cytokines between patients allocated to IVIG group and those allocated to placebo group. CONCLUSION: In ICU patients with NSTI, IVIG did not reduce the plasma concentration of cytokines in the first 3 days.

Long-term patient-important outcomes after septic shock: A protocol for 1-year follow-up of the CLASSIC trial.

BACKGROUND: In patients with septic shock, mortality is high, and survivors experience long-term physical, mental and social impairments. The ongoing Conservative vs Liberal Approach to fluid therapy of Septic Shock in Intensive Care (CLASSIC) trial assesses the benefits and harms of a restrictive vs standard-care intravenous (IV) fluid therapy. The hypothesis is that IV fluid restriction improves patient-important long-term outcomes. AIM: To assess the predefined patient-important long-term outcomes in patients randomised into the CLASSIC trial. METHODS: In this pre-planned follow-up study of the CLASSIC trial, we will assess all-cause mortality, health-related quality of life (HRQoL) and cognitive function 1 year after randomisation in the two intervention groups. The 1-year mortality will be collected from electronic patient records or central national registries in most participating countries. We will contact survivors and assess EuroQol 5-Dimension, -5-Level (EQ-5D-5L) and EuroQol-Visual Analogue Scale and Montreal Cognitive Assessment 5-minute protocol score. We will analyse mortality by logistic regression and use general linear models to assess HRQoL and cognitive function. DISCUSSION: With this pre-planned follow-up study of the CLASSIC trial, we will provide patient-important data on long-term survival, HRQoL and cognitive function of restrictive vs standard-care IV fluid therapy in patients with septic shock.

SuPAR correlates with mortality and clinical severity in patients with necrotizing soft-tissue infections: results from a prospective, observational cohort study.

Necrotizing soft tissue infections (NSTI) have a 90-day mortality rate of 18-22%. Tools are needed for estimating the prognosis and severity of NSTI upon admission. We evaluated soluble urokinase-type plasminogen activator receptor (suPAR) levels at admission as a prognostic marker of NSTI severity and mortality. In a prospective, observational cohort study, suPAR was measured in 200 NSTI patients. We compared admission suPAR levels in survivors and non-survivors, patients with septic shock and non-shock, amputation and non-amputation, correlations with Simplified Acute Physiology Score II (SAPS II) and the Sequential Organ Failure Assessment (SOFA) score. Admission suPAR levels were higher in septic shock vs. non-septic shock patients (9.2 vs. 5.8 ng/mL, p-value < 0.001) and non-survivors vs. survivors (11 vs. 6.1 ng/mL, p-value < 0.001) and correlated with SAPS II (r = 0.52, p < 0.001) and SOFA score (r = 0.64, p < 0.001). Elevated suPAR upon admission was associated with 90-day mortality (log-rank test p < 0.001), however not after adjustment for age, sex, and SOFA score. The AUC for suPAR and 90-day mortality was 0.77. We found that suPAR is a promising candidate for prognosis and severity in patients with NSTI.

Pantoprazole in Patients at Risk for Gastrointestinal Bleeding in the ICU.

BACKGROUND: Prophylaxis for gastrointestinal stress ulceration is frequently given to patients in the intensive care unit (ICU), but its risks and benefits are unclear. METHODS: In this European, multicenter, parallel-group, blinded trial, we randomly assigned adults who had been admitted to the ICU for an acute condition (i.e., an unplanned admission) and who were at risk for gastrointestinal bleeding to receive 40 mg of intravenous pantoprazole (a proton-pump inhibitor) or placebo daily during the ICU stay. The primary outcome was death by 90 days after randomization. RESULTS: A total of 3298 patients were enrolled; 1645 were randomly assigned to the pantoprazole group and 1653 to the placebo group. Data on the primary outcome were available for 3282 patients (99.5%). At 90 days, 510 patients (31.1%) in the pantoprazole group and 499 (30.4%) in the placebo group had died (relative risk, 1.02; 95% confidence interval [CI], 0.91 to 1.13; P=0.76). During the ICU stay, at least one clinically important event (a composite of clinically important gastrointestinal bleeding, pneumonia, Clostridium difficile infection, or myocardial ischemia) had occurred in 21.9% of patients assigned to pantoprazole and 22.6% of those assigned to placebo (relative risk, 0.96; 95% CI, 0.83 to 1.11). In the pantoprazole group, 2.5% of patients had clinically important gastrointestinal bleeding, as compared with 4.2% in the placebo group. The number of patients with infections or serious adverse reactions and the percentage of days alive without life support within 90 days were similar in the two groups. CONCLUSIONS: Among adult patients in the ICU who were at risk for gastrointestinal bleeding, mortality at 90 days and the number of clinically important events were similar in those assigned to pantoprazole and those assigned to placebo. (Funded by Innovation Fund Denmark and others; SUP-ICU ClinicalTrials.gov number, NCT02467621 .).

Effects of shorter versus longer storage time of transfused red blood cells in adult ICU patients: a systematic review with meta-analysis and Trial Sequential Analysis.

PURPOSE: Patients in the intensive care unit (ICU) are often transfused with red blood cells (RBC). During storage, the RBCs and storage medium undergo changes, which may have clinical consequences. Several trials now have assessed these consequences, and we reviewed the present evidence on the effects of shorter versus longer storage time of transfused RBCs on outcomes in ICU patients. METHODS: We conducted a systematic review with meta-analyses and trial sequential analyses (TSA) of randomised clinical trials including adult ICU patients transfused with fresher versus older or standard issue blood. RESULTS: We included seven trials with a total of 18,283 randomised ICU patients; two trials of 7504 patients were judged to have low risk of bias. We observed no effects of fresher versus older blood on death (relative risk 1.04, 95% confidence interval (CI) 0.97-1.11; 7349 patients; TSA-adjusted CI 0.93-1.15), adverse events (1.26, 0.76-2.09; 7332 patients; TSA-adjusted CI 0.16-9.87) or post-transfusion infections (1.07, 0.96-1.20; 7332 patients; TSA-adjusted CI 0.90-1.27). The results were unchanged by including trials with high risk of bias. TSA confirmed the results and the required information size was reached for mortality for a relative risk change of 20%. CONCLUSIONS: We may be able to reject a clinically meaningful effect of RBC storage time on mortality in transfused adult ICU patients as our trial sequential analyses reject a 10% relative risk change in death when comparing fresher versus older blood for transfusion.

Associations of Plasma Nitrite, L-Arginine and Asymmetric Dimethylarginine With Morbidity and Mortality in Patients With Necrotizing Soft Tissue Infections.

BACKGROUND: The nitric oxide system could play an important role in the pathophysiology related to necrotizing soft tissue infection (NSTI). Accordingly, we investigated the association between plasma nitrite level at admission and the presence of septic shock in patients with NSTI. We also evaluated the association between nitrite, asymmetric dimethylarginine (ADMA), L-arginine, L-arginine/ADMA ratio, and outcome. METHODS: We analyzed plasma from 141 NSTI patients taken upon hospital admission. The severity of NSTI was assessed by the presence of septic shock, Simplified Acute Physiology Score (SAPS) II, Sepsis-Related Organ Failure Assessment (SOFA) score, use of renal replacement therapy (RRT), amputation, and 28-day mortality. RESULTS: No difference in nitrite levels was found between patients with and without septic shock (median 0.82 µmol/L [interquartile range (IQR) 0.41-1.21] vs. 0.87 µmol/L (0.62-1.24), P = 0.25). ADMA level was higher in patients in need of RRT (0.64 µmol/L (IQR 0.47-0.90) vs. (0.52 µmol/L (0.34-0.70), P = 0.028), and ADMA levels correlated positively with SAPS II (rho = 0.32, P = 0.0002) and SOFA scores (rho = 0.22, P = 0.01). In a logistic regression analysis, an L-arginine/ADMA ratio below 101.59 was independently associated with 28-day mortality, odds ratio 6.03 (95% confidence interval, 1.41-25.84), P = 0.016. None of the other analyses indicated differences in the NO system based on differences in disease severity. CONCLUSIONS: In patients with NSTI, we found no difference in baseline nitrite levels according to septic shock. High baseline ADMA level was associated with the use of RRT and patients with a low baseline L-arginine/ADMA ratio were at higher risk of dying within 28 days after hospital admission.

Immunoglobulin G for patients with necrotising soft tissue infection (INSTINCT): a randomised, blinded, placebo-controlled trial.

PURPOSE: The aim of the INSTINCT trial was to assess the effect of intravenous polyspecific immunoglobulin G (IVIG) compared with placebo on self-reported physical function in intensive care unit (ICU) patients with necrotising soft tissue infection (NSTI). METHODS: We randomised 100 patients with NSTI 1:1 to masked infusion of 25 g of IVIG (Privigen, CSL Behring) or an equal volume of 0.9% saline once daily for the first 3 days of ICU admission. The primary outcome was the physical component summary (PCS) score of the 36-item short form health survey (SF-36) 6 months after randomisation; patients who had died were given the lowest possible score (zero). RESULTS: Of the 100 patients randomised, 87 were included in the intention-to-treat analysis of the PCS score, 42 patients (84%) in the IVIG group and 45 patients (90%) in the placebo group. The two intervention groups had similar baseline characteristics with the exception of IVIG use before randomisation (1 dose was allowed) and rates of acute kidney injury. Median PCS scores were 36 (interquartile range 0-43) in the group assigned to IVIG and 31 (0-47) in the group assigned to placebo (mean adjusted difference 1 (95% confidence interval -7 to 10), p = 0.81). The result was supported by analyses adjusted for baseline prognostics, those in the per protocol populations, in the subgroups (site of NSTI) and those done post hoc adjusted for IVIG use before randomisation. CONCLUSIONS: In ICU patients with NSTI, we observed no apparent effects of adjuvant IVIG on self-reported physical functioning at 6 months. TRIAL REGISTRATION: NCT02111161.

Biofilm in group A streptococcal necrotizing soft tissue infections.

Necrotizing fasciitis caused by group A streptococcus (GAS) is a life-threatening, rapidly progressing infection. At present, biofilm is not recognized as a potential problem in GAS necrotizing soft tissue infections (NSTI), as it is typically linked to chronic infections or associated with foreign devices. Here, we present a case of a previously healthy male presenting with NSTI caused by GAS. The infection persisted over 24 days, and the surgeon documented the presence of a "thick layer biofilm" in the fascia. Subsequent analysis of NSTI patient tissue biopsies prospectively included in a multicenter study revealed multiple areas of biofilm in 32% of the patients studied. Biopsies associated with biofilm formation were characterized by massive bacterial load, a pronounced inflammatory response, and clinical signs of more severe tissue involvement. In vitro infections of a human skin tissue model with GAS NSTI isolates also revealed multilayered fibrous biofilm structures, which were found to be under the control of the global Nra gene regulator. The finding of GAS biofilm formation in NSTIs emphasizes the urgent need for biofilm to be considered as a potential complicating microbiological feature of GAS NSTI and, consequently, emphasizes reconsideration of antibiotic treatment protocols.

Restricting volumes of resuscitation fluid in adults with septic shock after initial management: the CLASSIC randomised, parallel-group, multicentre feasibility trial.

PURPOSE: We assessed the effects of a protocol restricting resuscitation fluid vs. a standard care protocol after initial resuscitation in intensive care unit (ICU) patients with septic shock. METHODS: We randomised 151 adult patients with septic shock who had received initial fluid resuscitation in nine Scandinavian ICUs. In the fluid restriction group fluid boluses were permitted only if signs of severe hypoperfusion occurred, while in the standard care group fluid boluses were permitted as long as circulation continued to improve. RESULTS: The co-primary outcome measures, resuscitation fluid volumes at day 5 and during ICU stay, were lower in the fluid restriction group than in the standard care group [mean differences -1.2 L (95 % confidence interval -2.0 to -0.4); p < 0.001 and -1.4 L (-2.4 to -0.4) respectively; p < 0.001]. Neither total fluid inputs and balances nor serious adverse reactions differed statistically significantly between the groups. Major protocol violations occurred in 27/75 patients in the fluid restriction group. Ischaemic events occurred in 3/75 in the fluid restriction group vs. 9/76 in the standard care group (odds ratio 0.32; 0.08-1.27; p = 0.11), worsening of acute kidney injury in 27/73 vs. 39/72 (0.46; 0.23-0.92; p = 0.03), and death by 90 days in 25/75 vs. 31/76 (0.71; 0.36-1.40; p = 0.32). CONCLUSIONS: A protocol restricting resuscitation fluid successfully reduced volumes of resuscitation fluid compared with a standard care protocol in adult ICU patients with septic shock. The patient-centred outcomes all pointed towards benefit with fluid restriction, but our trial was not powered to show differences in these exploratory outcomes. TRIAL REGISTRATION: NCT02079402.

The Lectin Complement Pathway in Patients with Necrotizing Soft Tissue Infection.

BACKGROUND: Mannose-binding lectin (MBL) and ficolins are pattern recognition molecules (PRMs) that play an important role during infection through activation of the lectin complement pathway. We assessed whether plasma PRM levels were associated with mortality in patients with necrotizing soft tissue infection (NSTI). METHODS: We conducted a prospective, observational study over 25 months involving 135 NSTI patients with a maximum follow-up of 2.7 years. Blood samples were taken upon admission. Non-infected patients served as controls. RESULTS: PRM levels were significantly lower compared with controls. A baseline Ficolin-2 level below the median was associated with mortality at the end of follow-up (p = 0.007). No significant association was found for MBL, Ficolin-1 and Ficolin-3. A Ficolin-2 level below the median had a negative predictive value of 0.94 for 28-day mortality, and a level below the optimal cut-off was independently associated with 28-day mortality when adjusted for age, sex and chronicity [hazard ratio 6.27 (95% confidence interval 2.28-17.21), p < 0.0001], also when Simplified Acute Physiology Score II was included in the analysis [hazard ratio 3.16 (95% confidence interval 1.03-9.73), p = 0.045]. CONCLUSIONS: All PRMs were significantly lower in patients with NSTI than in controls. Only baseline Ficolin-2 was associated with short- and long-term mortality. A high baseline Ficolin-2 level indicated a 94% chance of surviving the first 28 days after admission.

The effect of a combination of plant sterol-enriched foods in mildly hypercholesterolemic subjects.

BACKGROUND & AIMS: The purpose of this study was to evaluate the effect of low-fat products enriched with plant sterols in addition to a National Cholesterol Education Program step 1 diet on serum lipids and lipoproteins. METHODS: This study was a double-blind, randomised, placebo-controlled cross-over design with a run-in period and 2 intervention periods, each lasting 4 weeks. A total of 46 mildly hypercholesterolemic subjects (age 50.6+/-9.8) completed the trial. The study products consisted of 20 g low-fat margarine (35% fat) and 250 ml low-fat milk (0.7% fat), in total delivering 2.3g plant sterols/d. RESULTS: Serum total and low-density lipoprotein cholesterol were significantly reduced by 5.5% (p<0.001, 95% CI: 2.5; 8.3) and 7.7% (p=0.001, 95% CI: 3.4; 11.9), respectively, by plant sterol-enriched products compared to placebo. Serum apolipoprotein B was significantly reduced by 4.6% (p<0.05, 95% CI: 1.7; 7.5), and apolipoprotein B/apolipoprotein A-I by 3.4% (p<0.05, 95% CI: 0.1; 6.6) after plant sterol intake compared to the placebo supplement. CONCLUSIONS: A combination of low-fat margarine and milk enriched with plant sterols significantly reduced low-density lipoprotein cholesterol, apolipoprotein B and the ratio of apolipoprotein B to apolipoprotein A-I in mildly hypercholesterolemic subjects, but had no effect on C-reactive protein and lipoprotein (a) concentrations. SPONSORSHIP: Unilever Denmark A/S.