Long-term immunosuppressive treatment is not associated with worse outcome in patients hospitalized in the intensive care unit for septic shock: the PACIFIC study.

BACKGROUND: Except in a few retrospective studies mainly including patients under chemotherapy, information regarding the impact of immunosuppressive therapy on the prognosis of patients admitted to the intensive care unit (ICU) for septic shock is scarce. Accordingly, the PACIFIC study aimed to asses if immunosuppressive therapy is associated with an increased mortality in patients admitted to the ICU for septic shock. METHODS: This was a retrospective epidemiological multicentre study. Eight high enroller centres in septic shock randomised controlled trials (RCTs) participated in the study. Patients in the "exposed" group were selected from the screen failure logs of seven recent RCTs and excluded because of immunosuppressive treatment. The "non-exposed" patients were those included in the placebo arm of the same RCTs. A multivariate logistic regression model was used to estimate the risk of death. RESULTS: Among the 433 patients enrolled, 103 were included in the "exposed" group and 330 in the "non-exposed" group. Reason for immunosuppressive therapy included organ transplantation (n = 45 [44%]) or systemic disease (n = 58 [56%]). ICU mortality rate was 24% in the "exposed" group and 25% in the "non-exposed" group (p = 0.9). Neither in univariate nor in multivariate analysis immunosuppressive therapy was associated with a higher ICU mortality (OR: 0.95; [95% CI 0.56-1.58]: p = 0.86 and 1.13 [95% CI 0.61-2.05]: p = 0.69, respectively) or 3-month mortality (OR: 1.13; [95% CI 0.69-1.82]: p = 0.62 and OR: 1.36 [95% CI 0.78-2.37]: p = 0.28, respectively). CONCLUSIONS: In this study, long-term immunosuppressive therapy excluding chemotherapy was not associated with significantly higher or lower ICU and 3-month mortality in patients admitted to the ICU for septic shock.

Prevention of Early Ventilator-Associated Pneumonia after Cardiac Arrest.

BACKGROUND: Patients who are treated with targeted temperature management after out-of-hospital cardiac arrest with shockable rhythm are at increased risk for ventilator-associated pneumonia. The benefit of preventive short-term antibiotic therapy has not been shown. METHODS: We conducted a multicenter, double-blind, randomized, placebo-controlled trial involving adult patients (>18 years of age) in intensive care units (ICUs) who were being mechanically ventilated after out-of-hospital cardiac arrest related to initial shockable rhythm and treated with targeted temperature management at 32 to 34°C. Patients with ongoing antibiotic therapy, chronic colonization with multidrug-resistant bacteria, or moribund status were excluded. Either intravenous amoxicillin-clavulanate (at doses of 1 g and 200 mg, respectively) or placebo was administered three times a day for 2 days, starting less than 6 hours after the cardiac arrest. The primary outcome was early ventilator-associated pneumonia (during the first 7 days of hospitalization). An independent adjudication committee determined diagnoses of ventilator-associated pneumonia. RESULTS: A total of 198 patients underwent randomization, and 194 were included in the analysis. After adjudication, 60 cases of ventilator-associated pneumonia were confirmed, including 51 of early ventilator-associated pneumonia. The incidence of early ventilator-associated pneumonia was lower with antibiotic prophylaxis than with placebo (19 patients [19%] vs. 32 [34%]; hazard ratio, 0.53; 95% confidence interval, 0.31 to 0.92; P = 0.03). No significant differences between the antibiotic group and the control group were observed with respect to the incidence of late ventilator-associated pneumonia (4% and 5%, respectively), the number of ventilator-free days (21 days and 19 days), ICU length of stay (5 days and 8 days if patients were discharged and 7 days and 7 days if patients had died), and mortality at day 28 (41% and 37%). At day 7, no increase in resistant bacteria was identified. Serious adverse events did not differ significantly between the two groups. CONCLUSIONS: A 2-day course of antibiotic therapy with amoxicillin-clavulanate in patients receiving a 32-to-34°C targeted temperature management strategy after out-of-hospital cardiac arrest with initial shockable rhythm resulted in a lower incidence of early ventilator-associated pneumonia than placebo. No significant between-group differences were observed for other key clinical variables, such as ventilator-free days and mortality at day 28. (Funded by the French Ministry of Health; ANTHARTIC ClinicalTrials.gov number, NCT02186951.).

High prevalence of infections in non-COVID-19 patients admitted to the Emergency Department with severe lymphopenia.

BACKGROUND: In the Emergency Department (ED), early and accurate recognition of infection is crucial to prompt antibiotic therapy but the initial presentation of patients is variable and poorly characterized. Lymphopenia is commonly associated with bacteraemia and poor outcome in intensive care unit patients. The objective of this retrospective study was to assess the prevalence of community-acquired infection in a cohort of unselected patients admitted to the ED with undifferentiated symptoms and severe lymphopenia. METHODS: This is a retrospective single-center study conducted over a 1 year-period before the COVID-19 pandemic. Consecutive adult patients admitted to the ED with severe lymphopenia (lymphocyte count < 0.5 G/L) were studied. Patients with hematological or oncological diseases, HIV infection, hepato-cellular deficiency, immunosuppression, or patients over 85 years old were excluded. Diagnoses of infection were validated by an independent adjudication committee. The association between various parameters and infection was assessed using a multivariate logistic regression analysis. RESULTS: Of 953 patients admitted to the ED with severe lymphopenia, 245 were studied (148 men; mean age: 63 ± 19 years). Infection was confirmed in 159 patients (65%) (bacterial: 60%, viral: 30%, other: 10%). Only 61 patients (25%) were referred to the ED for a suspected infection. In the univariate analysis, SIRS criteria (OR: 5.39; 95%CI: 3.04-9.70; p < 0.001) and temperature ≥ 38.3 °C (OR: 10.95; 95%CI: 5.39-22.26; p < 0.001) were strongly associate with infection. In the multivariate analysis, only SIRS criteria (OR: 2.4; 95%CI: 1.48-3.9; p < 0.01) and fever (OR: 3.35; 95%CI: 1.26-8.93; p = 0.016) were independently associated with infection. CONCLUSIONS: The prevalence of underlying infection is high in patients admitted to the ED with lymphopenia, irrespective of the reason for admission. Whether lymphopenia could constitute a valuable marker of underlying infection in this clinical setting remains to be confirmed prospectively in larger cohorts. TRIAL REGISTRATION: No registration required as this is a retrospective study.

Serial measurement of pancreatic stone protein for the early detection of sepsis in intensive care unit patients: a prospective multicentric study.

BACKGROUND: The early recognition and management of sepsis improves outcomes. Biomarkers may help in identifying earlier sub-clinical signs of sepsis. We explored the potential of serial measurements of C-reactive protein (CRP), procalcitonin (PCT) and pancreatic stone protein (PSP) for the early recognition of sepsis in patients hospitalized in the intensive care unit (ICU). METHODS: This was a multicentric international prospective observational clinical study conducted in 14 ICUs in France, Switzerland, Italy, and the United Kingdom. Adult ICU patients at risk of nosocomial sepsis were included. A biomarker-blinded adjudication committee identified sepsis events and the days on which they began. The association of clinical sepsis diagnoses with the trajectories of PSP, CRP, and PCT in the 3 days preceding these diagnoses of sepsis were tested for markers of early sepsis detection. The performance of the biomarkers in sepsis diagnosis was assessed by receiver operating characteristic (ROC) analysis. RESULTS: Of the 243 patients included, 53 developed nosocomial sepsis after a median of 6 days (interquartile range, 3-8 days). Clinical sepsis diagnosis was associated with an increase in biomarkers value over the 3 days preceding this diagnosis [PSP (p = 0.003), PCT (p = 0.025) and CRP (p = 0.009)]. PSP started to increase 5 days before the clinical diagnosis of sepsis, PCT 3 and CRP 2 days, respectively. The area under the ROC curve at the time of clinical sepsis was similar for all markers (PSP, 0.75; CRP, 0.77; PCT, 0.75). CONCLUSIONS: While the diagnostic accuracy of PSP, CRP and PCT for sepsis were similar in this cohort, serial PSP measurement demonstrated an increase of this marker the days preceding the onset of signs necessary to clinical diagnose sepsis. This observation justifies further evaluation of the potential clinical benefit of serial PSP measurement in the management of critically ill patients developing nosocomial sepsis. Trial registration The study has been registered at ClinicalTrials.gov (no. NCT03474809), on March 16, 2018. https://www.clinicaltrials.gov/ct2/show/NCT03474809?term=NCT03474809&draw=2&rank=1 .

Spontaneous community-acquired PVL-producing Staphylococcus aureus mediastinitis in an immunocompetent adult - a case report.

BACKGROUND: Mediastinitis caused by hematogenous spread of an infection is rare. We report the first known case of community-acquired mediastinitis from hematogenous origin in an immunocompetent adult. This rare invasive infection was due to Panton-Valentine Leucocidin-producing (PVL+) methicillin-susceptible Staphylococcus aureus (MSSA). CASE PRESENTATION: A 22-year-old obese man without other medical history was hospitalized for febrile precordial chest pain. He reported a cutaneous back abscess 3 weeks before. CT-scan was consistent with mediastinitis and blood cultures grew for a PVL+ MSSA. Intravenous clindamycin (600 mg t.i.d) and cloxacillin (2 g q.i.d.), secondary changed for fosfomycin (4 g q.i.d.) because of a related toxidermia, was administered. Surgical drainage was performed and confirmed the presence of a mediastinal abscess associated with a fistula between the mediastinum and right pleural space. All local bacteriological samples also grew for PVL+ MSSA. In addition to clindamycin, intravenous fosfomycin was switched to trimethoprim-sulfamethoxazole after 4 weeks for a total of 10 weeks of antibiotics. CONCLUSIONS: We present the first community-acquired mediastinitis of hematogenous origin with PVL+ MSSA. Clinical evolution was favorable after surgical drainage and 10 weeks of antibiotics. The specific virulence of MSSA PVL+ strains played presumably a key role in this rare invasive clinical presentation.

Community-acquired Staphylococcus aureus bacteriuria: a warning microbiological marker for infective endocarditis?

BACKGROUND: Urinary tract infection (UTI) is frequently diagnosed in the Emergency Department (ED). Staphylococcus aureus (SA) is an uncommon isolate in urine cultures (0.5-6% of positive urine cultures), except in patients with risk factors for urinary tract colonization. In the absence of risk factors, community-acquired SA bacteriuria may be related to deep-seated SA infection including infective endocarditis. We hypothesized that SA bacteriuria could be a warning microbiological marker of unsuspected infective endocarditis in the ED. METHODS: This is a retrospective chart review of consecutive adult patients between December 2005 and February 2018. All patients admitted in the ED with both SA bacteriuria (104 CFU/ml SA isolated from a single urine sample) and SA bacteremia, without risk factors for UT colonization (i.e., < 1 month UT surgery, UT catheterization) were analyzed. Diagnosis of infective endocarditis was based on the Duke criteria. RESULTS: During the study period, 27 patients (18 men; median age: 61 [IQR: 52-73] years) were diagnosed with community-acquired SA bacteriuria and had subsequently documented bacteremia and SA infective endocarditis. Only 5 patients (18%) had symptoms related to UT infection. Median delay between ED admission and SA bacteriuria identification was significantly shorter than that between ED admission and the diagnosis of infective endocarditis (1.4 ± 0.8 vs. 4.3 ± 4.2 days: p = 0.01). Mitral and aortic valves were most frequently involved by infective endocarditis (93%). Mortality on day 60 reached 56%. CONCLUSIONS: This study suggests that community-acquired SA bacteriuria should warn the emergency physician about a potentially associated left-sided infective endocarditis in ED patients without risk factors for UT colonization.

Phagosomal granulocytic ROS in septic patients induce the bacterial SOS response.

Septic patients with worst clinical prognosis have increased circulating immature granulocytes (IG), displaying limited phagocytosis and reactive oxygen species (ROS) production. Here, we developed an ex vivo model of incubation of human granulocytes, from septic patients or healthy donors, with Escherichia coli. We showed that the ROS production in Sepsis-IG is lower due to decreased activation and protein expression of the NADPH oxidase complex. We also demonstrated that the low level of ROS production and lower phagocytosis of IG in sepsis induce the bacterial SOS response, leading to the expression of the SOS-regulated quinolone resistance gene qnrB2. Without antimicrobial pressure, the sepsis immune response alone may promote antibiotic resistance expression.

Can Biomarkers Correctly Predict Ventilator-associated Pneumonia in Patients Treated With Targeted Temperature Management After Cardiac Arrest? An Exploratory Study of the Multicenter Randomized Antibiotic (ANTHARTIC) Study.

IMPORTANCE: Ventilator-associated pneumonia (VAP) frequently occurs in patients with cardiac arrest. Diagnosis of VAP after cardiac arrest remains challenging, while the use of current biomarkers such as C-reactive protein (CRP) or procalcitonin (PCT) is debated. OBJECTIVES: To evaluate biomarkers' impact in helping VAP diagnosis after cardiac arrest. DESIGN SETTING AND PARTICIPANTS: This is a prospective ancillary study of the randomized, multicenter, double-blind placebo-controlled ANtibiotherapy during Therapeutic HypothermiA to pRevenT Infectious Complications (ANTHARTIC) trial evaluating the impact of antibiotic prophylaxis to prevent VAP in out-of-hospital patients with cardiac arrest secondary to shockable rhythm and treated with therapeutic hypothermia. An adjudication committee blindly evaluated VAP according to predefined clinical, radiologic, and microbiological criteria. All patients with available biomarker(s), sample(s), and consent approval were included. MAIN OUTCOMES AND MEASURES: The main endpoint was to evaluate the ability of biomarkers to correctly diagnose and predict VAP within 48 hours after sampling. The secondary endpoint was to study the combination of two biomarkers in discriminating VAP. Blood samples were collected at baseline on day 3. Routine and exploratory panel of inflammatory biomarkers measurements were blindly performed. Analyses were adjusted on the randomization group. RESULTS: Among 161 patients of the ANTHARTIC trial with available biological sample(s), patients with VAP (n = 33) had higher body mass index and Acute Physiology and Chronic Health Evaluation II score, more unwitnessed cardiac arrest, more catecholamines, and experienced more prolonged therapeutic hypothermia duration than patients without VAP (n = 121). In univariate analyses, biomarkers significantly associated with VAP and showing an area under the curve (AUC) greater than 0.70 were CRP (AUC = 0.76), interleukin (IL) 17A and 17C (IL17C) (0.74), macrophage colony-stimulating factor 1 (0.73), PCT (0.72), and vascular endothelial growth factor A (VEGF-A) (0.71). Multivariate analysis combining novel biomarkers revealed several pairs with p value of less than 0.001 and odds ratio greater than 1: VEGF-A + IL12 subunit beta (IL12B), Fms-related tyrosine kinase 3 ligands (Flt3L) + C-C chemokine 20 (CCL20), Flt3L + IL17A, Flt3L + IL6, STAM-binding protein (STAMBP) + CCL20, STAMBP + IL6, CCL20 + 4EBP1, CCL20 + caspase-8 (CASP8), IL6 + 4EBP1, and IL6 + CASP8. Best AUCs were observed for CRP + IL6 (0.79), CRP + CCL20 (0.78), CRP + IL17A, and CRP + IL17C. CONCLUSIONS AND RELEVANCE: Our exploratory study shows that specific biomarkers, especially CRP combined with IL6, could help to better diagnose or predict early VAP occurrence in cardiac arrest patients.

Along with PaO2/FiO2 ratio and lymphopenia, low HLA-DR monocytes are the only additional parameter that independently predicts the clinical course of undifferentiated SARS-CoV-2 patients in emergency departments.

Because one-third of patients deteriorate after their admission to the emergency department, assessing the prognosis of COVID-19 patients is of great importance. However, to date, only lymphopenia and the partial pressure of oxygen/fraction of inspired oxygen (PaO2/FiO2) ratio have been reported as partly predictive of COVID-19-related further deterioration, and their association has not been evaluated. We asked whether other key biomarkers of SARS-CoV-2 immunologic defects-increase in circulating immature granulocytes, loss of monocyte HLA-DR (mHLA-DR) expression, and monocyte differentiation blockade-could also predict further COVID-19 deterioration. A series of 284 consecutive COVID-19 patients, with the sole inclusion criterion of being an adult, were prospectively enrolled at emergency department admission (day 0) of 2 different hospitals: 1 for the exploratory cohort (180 patients) and 1 for the confirmatory cohort (104 patients). Deterioration was assessed over the next 7 days. Neither increased immature granulocyte levels nor monocyte differentiation blockade predicted patient worsening. Among more than 30 clinical, biological, and radiological parameters, the value of decreased P/F ratio and lymphopenia for prediction of further COVID-19 deterioration was strongly confirmed, and the loss of mHLA-DR was the only additional independent marker. Combined together in a simple OxyLymphoMono score, the 3 variables perfectly predicted patients who did not worsen and correctly predicted worsening in 59% of cases. By highlighting lymphocyte and monocyte defects as preceding COVID-19 deterioration, these results point on early immunosuppression in COVID-19 deterioration. Combining P/F ratio, lymphopenia, and loss of mHLA-DR together in a simple and robust score could offer a pragmatic method for COVID-19 patient stratification.

Clinical phenotypes and outcomes associated with SARS-CoV-2 Omicron sublineage JN.1 in critically ill COVID-19 patients: a prospective, multicenter cohort study in France, November 2022 to January 2024.

BACKGROUND: A notable increase in severe cases of COVID-19, with significant hospitalizations due to the emergence and spread of JN.1 was observed worldwide in late 2023 and early 2024. However, no clinical data are available regarding critically-ill JN.1 COVID-19 infected patients. METHODS: The current study is a substudy of the SEVARVIR prospective multicenter observational cohort study. Patients admitted to any of the 40 participating ICUs between November 17, 2022, and January 22, 2024, were eligible for inclusion in the SEVARVIR cohort study (NCT05162508) if they met the following inclusion criteria: age ≥ 18 years, SARS-CoV-2 infection confirmed by a positive reverse transcriptase-polymerase chain reaction (RT-PCR) in nasopharyngeal swab samples, ICU admission for acute respiratory failure. The primary clinical endpoint of the study was day-28 mortality. Evaluation of the association between day-28 mortality and sublineage group was conducted by performing an exploratory multivariable logistic regression model, after systematically adjusting for predefined prognostic factors previously shown to be important confounders (i.e. obesity, immunosuppression, age and SOFA score) computing odds ratios (OR) along with their corresponding 95% confidence intervals (95% CI). RESULTS: During the study period (November 2022-January 2024) 56 JN.1- and 126 XBB-infected patients were prospectively enrolled in 40 French intensive care units. JN.1-infected patients were more likely to be obese (35.7% vs 20.8%; p = 0.033) and less frequently immunosuppressed than others (20.4% vs 41.4%; p = 0.010). JN.1-infected patients required invasive mechanical ventilation support in 29.1%, 87.5% of them received dexamethasone, 14.5% tocilizumab and none received monoclonal antibodies. Only one JN-1 infected patient (1.8%) required extracorporeal membrane oxygenation support during ICU stay (vs 0/126 in the XBB group; p = 0.30). Day-28 mortality of JN.1-infected patients was 14.6%, not significantly different from that of XBB-infected patients (22.0%; p = 0.28). In univariable logistic regression analysis and in multivariable analysis adjusting for confounders defined a priori, we found no statistically significant association between JN.1 infection and day-28 mortality (adjusted OR 1.06 95% CI (0.17;1.42); p = 0.19). There was no significant between group difference regarding duration of stay in the ICU (6.0 [3.5;11.0] vs 7.0 [4.0;14.0] days; p = 0.21). CONCLUSIONS: Critically-ill patients with Omicron JN.1 infection showed a different clinical phenotype than patients infected with the earlier XBB sublineage, including more frequent obesity and less immunosuppression. Compared with XBB, JN.1 infection was not associated with higher day-28 mortality.

COVID-19 associated pulmonary aspergillosis in critically-ill patients: a prospective multicenter study in the era of Delta and Omicron variants.

BACKGROUND: During the first COVID-19 pandemic wave, COVID-19-associated pulmonary aspergillosis (CAPA) has been reported in up to 11-28% of critically ill COVID-19 patients and associated with increased mortality. As new SARS-CoV-2 variants emerged, the characteristics of critically ill COVID-19 patients have evolved, particularly in the era of Omicron. The purpose of this study is to investigate the characteristics of CAPA in the era of new variants. METHODS: This is a prospective multicenter observational cohort study conducted in France in 36 participating intensive care units (ICU), between December 7th, 2021 and April 26th 2023. Diagnosis criteria of CAPA relied on European Confederation of Medical Mycology (ECMM)/International Society for Human & Animal Mycology (ISHAM) consensus criteria. RESULTS: 566 patients were included over the study period. The prevalence of CAPA was 5.1% [95% CI 3.4-7.3], and rose to 9.1% among patients who required invasive mechanical ventilation (IMV). Univariable analysis showed that CAPA patients were more frequently immunosuppressed and required more frequently IMV support, vasopressors and renal replacement therapy during ICU stay than non-CAPA patients. SAPS II score at ICU admission, immunosuppression, and a SARS-CoV-2 Delta variant were independently associated with CAPA in multivariable logistic regression analysis. Although CAPA was not significantly associated with day-28 mortality, patients with CAPA experienced a longer duration of mechanical ventilation and ICU stay. CONCLUSION: This study contributes valuable insights into the prevalence, characteristics, and outcomes of CAPA in the era of Delta and Omicron variants. We report a lower prevalence of CAPA (5.1%) among critically-ill COVID-19 patients than previously reported, mainly affecting intubated-patients. Duration of mechanical ventilation and ICU stay were significantly longer in CAPA patients.

SEPSIS UNIT IN THE EMERGENCY DEPARTMENT: IMPACT ON MANAGEMENT AND OUTCOME OF SEPTIC PATIENTS.

ABSTRACT: Study hypothesis : Implementation of a new pathway dedicated to septic patients within the emergency department (ED) would improve early management, organ dysfunction, and outcome. Methods: During phase 1, all consecutive adult patients with infection and qualifying quick Sequential Organ Failure Assessment (qSOFA) score upon ED admission were managed according to standards of care. A multifaceted intervention was then performed (implementation phase): educational program, creation of a sepsis alert upon ED admission incorporated in the professional software, together with severity scores and Surviving Sepsis Campaign (SSC) bundle reminders, and dedication of two rooms to the management of septic patients (sepsis unit). During phase 2, patients were managed according to this new organization. Results: Of the 89,040 patients admitted to the ED over the two phases, 2,643 patients (3.2%) had sepsis including 277 with a qualifying qSOFA score on admission (phase 1, 141 patients; phase 2, 136 patients). Recommendations of SSC 3-h bundle significantly improved between the two periods regarding lactate measurement (87% vs. 96%, P = 0.006), initiation of fluid resuscitation (36% vs. 65%, P < 0.001), blood cultures sampling (83% vs. 93%, P = 0.014), and administration of antibiotics (18% vs. 46%, P < 0.001). The Sequential Organ Failure Assessment score between H0 and H12 varied significantly more during phase 2 (1.9 ± 1.9 vs. 0.8 ± 2.6, P < 0.001). Mortality significantly decreased during the second phase, on day 3 (28% vs. 15%, P = 0.008) and on day 28 (40% vs. 28%, P = 0.013). Conclusion: Systematic detection, education, and per protocol organization with a sepsis unit dedicated to the early management of septic patients appear to improve compliance with SSC bundles, organ dysfunction, and short-term mortality. These results warrant to be confirmed by prospective studies.

Intravenously administered interleukin-7 to reverse lymphopenia in patients with septic shock: a double-blind, randomized, placebo-controlled trial.

BACKGROUND: Profound lymphopenia is an independent predictor of adverse clinical outcomes in sepsis. Interleukin-7 (IL-7) is essential for lymphocyte proliferation and survival. A previous phase II study showed that CYT107, a glycosylated recombinant human IL-7, administered intramuscularly reversed sepsis-induced lymphopenia and improved lymphocyte function. Thepresent study evaluated intravenous administration of CYT107. This prospective, double-blinded, placebo-controlled trial was designed to enroll 40 sepsis patients, randomized 3:1 to CYT107 (10 µg/kg) or placebo, for up to 90 days. RESULTS: Twenty-one patients were enrolled (fifteen CYT107 group, six placebo group) at eight French and two US sites. The study was halted early because three of fifteen patients receiving intravenous CYT107 developed fever and respiratory distress approximately 5-8 h after drug administration. Intravenous administration of CYT107 resulted in a two-threefold increase in absolute lymphocyte counts (including in both CD4+ and CD8+ T cells (all p < 0.05)) compared to placebo. This increase was similar to that seen with intramuscular administration of CYT107, was maintained throughout follow-up, reversed severe lymphopenia and was associated with increase in organ support free days (OSFD). However, intravenous CYT107 produced an approximately 100-fold increase in CYT107 blood concentration compared with intramuscular CYT107. No cytokine storm and no formation of antibodies to CYT107 were observed. CONCLUSION: Intravenous CYT107 reversed sepsis-induced lymphopenia. However, compared to intramuscular CYT107 administration, it was associated with transient respiratory distress without long-term sequelae. Because of equivalent positive laboratory and clinical responses, more favorable pharmacokinetics, and better patient tolerability, intramuscular administration of CYT107 is preferable. TRIAL REGISTRATION: Clinicaltrials.gov, NCT03821038. Registered 29 January 2019, https://clinicaltrials.gov/ct2/show/NCT03821038?term=NCT03821038&draw=2&rank=1 .

Demultiplexing Ig repertoires by parallel mRNA/DNA sequencing shows major differential alterations in severe COVID-19.

To understand the fine differential elements that can lead to or prevent acute respiratory distress syndrome (ARDS) in COVID-19 patients, it is crucial to investigate the immune response architecture. We herein dissected the multiple layers of B cell responses by flow cytometry and Ig repertoire analysis from acute phase to recovery. Flow cytometry with FlowSOM analysis showed major changes associated with COVID-19 inflammation such as an increase of double-negative B-cells and ongoing plasma cell differentiation. This paralleled COVID-19-driven expansion of two disconnected B-cell repertoires. Demultiplexing successive DNA and RNA Ig repertoire patterns characterized an early expansion of IgG1 clonotypes with atypically long and uncharged CDR3, the abundance of this inflammatory repertoire being correlated with ARDS and likely pejorative. A superimposed convergent response included convergent anti-SARS-CoV-2 clonotypes. It featured progressively increasing somatic hypermutation together with normal-length or short CDR3 and it persisted until a quiescent memory B-cell stage after recovery.

Bicentric evaluation of stabilizing sampling tubes for assessment of monocyte HLA-DR expression in clinical samples.

BACKGROUND: Diminished expression of human leukocyte antigen DR on circulating monocytes (mHLA-DR), measured by standardized flow cytometry procedure, is a reliable indicator of immunosuppression in severely injured intensive care unit patients. As such, it is used as stratification criteria in clinical trials evaluating novel immunostimulating therapies. Preanalytical constraints relative to the short delay between blood sampling and flow cytometry staining have nevertheless limited its use in multicentric studies. The objective of the present work was to compare mHLA-DR expression between whole blood samples simultaneously drawn in EDTA or Cyto-Chex BCT tubes. METHODS: In two university hospitals, mHLA-DR was assessed in fresh whole blood from septic patients (n = 12) and healthy donors (n = 6) simultaneously sampled on EDTA and Cyto-Chex BCT tubes. Staining was performed immediately after sampling and after blood storage at room temperature. RESULTS: We confirmed that samples collected in Cyto-Chex tube had substantially enhanced stability for mHLA-DR results (48-72 h) over those collected in EDTA. On baseline values, despite good correlation between tubes (r = 0.98, p < 0.001), mHLA-DR expression was systematically lower with Cyto-Chex BCT. CONCLUSION: The present reports confirms the potential of Cyto-Chex BCT tubes to stabilize mHLA-DR expression before staining and extends the work of Quadrini et al. [Cytometry B 2021;100:103-114]. In centers without rapid access to flow cytometry facilities, it enables to tolerate delays in mHLA-DR staining. However, a 30% gap exists between results obtained with EDTA and Cyto-Chex BCT tubes. As current thresholds for clinical decisions were obtained with EDTA samples, further studies are needed to confirm clinical thresholds with Cyto-Chex BCT tubes.

De novo natural anti-M alloantibody emergence in severe Coronavirus Disease 2019.

The immune response is a key player in the course of SARS-CoV-2 infection, and is often seriously dysfunctional in severe Coronavirus Disease 2019. The hyperinflammatory status has been described to be accompanied by the appearance of autoantibodies. In a lethal COVID-19 infection, we observed the emergence of a de novo natural alloantibody which targeted the M antigen from the MNS blood group on red blood cells (RBC) without evidence of any cross-reaction with SARS-CoV-2 antigens. This IgM lambda alloantibody was unmutated and unswitched. Here, we describe for the first time the emergence of a bystander de novo natural alloantibody against RBCs in a severe COVID-19 patient, highlighting the extra-follicular humoral response reported in these cases.

Immature granulocytes can help the diagnosis of pulmonary bacterial infections in patients with severe COVID-19 pneumonia.

During COVID-19, immature granulocyte (IG) concentration is heterogeneous with higher concentrations than those found in bacterial sepsis. We investigated the relationship between IG levels at ICU admission and on days 7 (± 2) and 15 (± 2) and associated pulmonary bacterial infections in intensive care unit (ICU) patients hospitalized for an acute respiratory distress syndrome (ARDS) related to SARS-CoV-2. Patients with associated pulmonary bacterial infection had a peak of IGs. IG thresholds of 18% or 2 G/L allowed discriminating patients with ventilator associated pneumonia with 100% sensitivity and specificity. Our study supports that IGs could help identifying pulmonary bacterial infections in this population.

Comparative immune profiling of acute respiratory distress syndrome patients with or without SARS-CoV-2 infection.

Acute respiratory distress syndrome (ARDS) is the main complication of coronavirus disease 2019 (COVID-19), requiring admission to the intensive care unit (ICU). Despite extensive immune profiling of COVID-19 patients, to what extent COVID-19-associated ARDS differs from other causes of ARDS remains unknown. To address this question, here, we build 3 cohorts of patients categorized in COVID-19-ARDS+, COVID-19+ARDS+, and COVID-19+ARDS-, and compare, by high-dimensional mass cytometry, their immune landscape. A cell signature associating S100A9/calprotectin-producing CD169+ monocytes, plasmablasts, and Th1 cells is found in COVID-19+ARDS+, unlike COVID-19-ARDS+ patients. Moreover, this signature is essentially shared with COVID-19+ARDS- patients, suggesting that severe COVID-19 patients, whether or not they experience ARDS, display similar immune profiles. We show an increase in CD14+HLA-DRlow and CD14lowCD16+ monocytes correlating to the occurrence of adverse events during the ICU stay. We demonstrate that COVID-19-associated ARDS displays a specific immune profile and may benefit from personalized therapy in addition to standard ARDS management.

New Agents in Development for Sepsis: Any Reason for Hope?

Sepsis is a syndrome which is defined as a dysregulated host response to infection leading to organ failure. Since it remains one of the leading causes of mortality worldwide, numerous drug candidates have already been tested, and continue to be developed, as potential adjunct therapies. Despite convincing mechanisms of action and robust pre-clinical data, almost all drug candidates in the field of sepsis have failed to demonstrate clinical efficacy in the past two decades. Accordingly, the development of new sepsis drugs has markedly decreased in the past few years. Nevertheless, thanks to a better understanding of sepsis pathophysiology and pathways, new promising drug candidates are currently being developed. Instead of a unique sepsis profile as initially suspected, various phenotypes have been characterised. This has  resulted in the identification of multiple targets for new drugs together with relevant biomarkers, and a better understanding of the most appropriate time to intervention. Within the entire sepsis drugs portfolio, those targeting the immune response are probably the most promising. Monoclonal antibodies targeting either cytokines or infectious agents are undoubtedly part of the potential successful therapeutic classes to come.