Activate: Randomized Clinical Trial of BCG Vaccination against Infection in the Elderly.

BCG vaccination in children protects against heterologous infections and improves survival independently of tuberculosis prevention. The phase III ACTIVATE trial assessed whether BCG has similar effects in the elderly. In this double-blind, randomized trial, elderly patients (n = 198) received BCG or placebo vaccine at hospital discharge and were followed for 12 months for new infections. At interim analysis, BCG vaccination significantly increased the time to first infection (median 16 weeks compared to 11 weeks after placebo). The incidence of new infections was 42.3% (95% CIs 31.9%-53.4%) after placebo vaccination and 25.0% (95% CIs 16.4%-36.1%) after BCG vaccination; most of the protection was against respiratory tract infections of probable viral origin (hazard ratio 0.21, p = 0.013). No difference in the frequency of adverse effects was found. Data show that BCG vaccination is safe and can protect the elderly against infections. Larger studies are needed to assess protection against respiratory infections, including COVID-19 (ClinicalTrials.gov NCT03296423).

qSOFA combined with suPAR for early risk detection and guidance of antibiotic treatment in the emergency department: a randomized controlled trial.

BACKGROUND: Sepsis guidelines suggest immediate start of resuscitation for patients with quick Sequential Organ Failure Assessment (qSOFA) 2 or 3. However, the interpretation of qSOFA 1 remains controversial. We investigated whether measurements of soluble urokinase plasminogen activator receptor (suPAR) may improve risk detection when qSOFA is 1. METHODS: The study had two parts. At the first part, the combination of suPAR with qSOFA was analyzed in a prospective cohort for early risk detection. At the second part, the double-blind, randomized controlled trial (RCT) SUPERIOR evaluated the efficacy of the suPAR-guided medical intervention. SUPERIOR took place between November 2018 and December 2020. Multivariate stepwise Cox regression was used for the prospective cohort, while univariate and multivariate logistic regression was used for the RCT. Consecutive admissions at the emergency department (ED) with suspected infection, qSOFA 1 and suPAR ≥ 12 ng/mL were allocated to single infusion of placebo or meropenem. The primary endpoint was early deterioration, defined as at least one-point increase of admission Sequential Organ Failure Assessment (SOFA) score the first 24 h. RESULTS: Most of the mortality risk was for patients with qSOFA 2 and 3. Taking the hazard ratio (HR) for death of patients with qSOFA = 1 and suPAR < 12 ng/mL as reference, the HR of qSOFA = 1 and suPAR ≥ 12 ng/mL for 28-day mortality was 2.98 (95% CI 2.11-3.96). The prospective RCT was prematurely ended due to pandemia-related ED re-allocations, with 91 patients enrolled: 47 in the placebo and 44 in the meropenem arm. The primary endpoint was met in 40.4% (n = 19) and 15.9% (n = 7), respectively (difference 24.5% [5.9-40.8]; odds ratio 0.14 [0.04-0.50]). One post hoc analysis showed significant median changes of SOFA score after 72 and 96 h equal to 0 and - 1, respectively. CONCLUSIONS: Combining qSOFA 1 with the biomarker suPAR improves its prognostic performance for unfavorable outcome and can help decision for earlier treatment. Trial registration EU Clinical Trials Register (EudraCT, 2018-001008-13) and Clinical-Trials.gov (NCT03717350). Registered 24 October 2018.

Host cystathionine-γ lyase derived hydrogen sulfide protects against Pseudomonas aeruginosa sepsis.

Hydrogen sulfide (H2S) has recently been recognized as a novel gaseous transmitter with several anti-inflammatory properties. The role of host- derived H2S in infections by Pseudomonas aeruginosa was investigated in clinical and mouse models. H2S concentrations and survival was assessed in septic patients with lung infection. Animal experiments using a model of severe systemic multidrug-resistant P. aeruginosa infection were performed using mice with a constitutive knock-out of cystathionine-γ lyase (Cse) gene (Cse-/-) and wild-type mice with a physiological expression (Cse+/+). Experiments were repeated in mice after a) treatment with cyclophosphamide; b) bone marrow transplantation (BMT) from a Cse+/+ donor; c) treatment with H2S synthesis inhibitor aminooxyacetic acid (ΑΟΑΑ) or propargylglycine (PAG) and d) H2S donor sodium thiosulfate (STS) or GYY3147. Bacterial loads and myeloperoxidase activity were measured in tissue samples. The expression of quorum sensing genes (QS) was determined in vivo and in vitro. Cytokine concentration was measured in serum and incubated splenocytes. Patients survivors at day 28 had significantly higher serum H2S compared to non-survivors. A cut- off point of 5.3 µΜ discriminated survivors with sensitivity 92.3%. Mortality after 28 days was 30.9% and 93.7% in patients with H2S higher and less than 5.3 µΜ (p = 7 x 10-6). In mice expression of Cse and application of STS afforded protection against infection with multidrug-resistant P. aeruginosa. Cyclophosphamide pretreatment eliminated the survival benefit of Cse+/+ mice, whereas BMT increased the survival of Cse-/- mice. Cse-/- mice had increased pathogen loads compared to Cse+/+ mice. Phagocytic activity of leukocytes from Cse-/- mice was reduced but was restored after H2S supplementation. An H2S dependent down- regulation of quorum sensing genes of P.aeruginosa could be demonstrated in vivo and in vitro. Endogenous H2S is a potential independent parameter correlating with the outcome of P. aeruginosa. H2S provides resistance to infection by MDR bacterial pathogens.

A novel optical biosensor for the early diagnosis of sepsis and severe Covid-19: the PROUD study.

BACKGROUND: The accuracy of a new optical biosensor (OB) point-of-care device for the detection of severe infections is studied. METHODS: The OB emits different wavelengths and outputs information associated with heart rate, pulse oximetry, levels of nitric oxide and kidney function. At the first phase, recordings were done every two hours for three consecutive days after hospital admission in 142 patients at high-risk for sepsis by placing the OB on the forefinger. At the second phase, single recordings were done in 54 patients with symptoms of viral infection; 38 were diagnosed with COVID-19. RESULTS: At the first phase, the cutoff value of positive likelihood of 18 provided 100% specificity and 100% positive predictive value for the diagnosis of sepsis. These were 87.5 and 91.7% respectively at the second phase. OB diagnosed severe COVID-19 with 83.3% sensitivity and 87.5% negative predictive value. CONCLUSIONS: The studied OB seems valuable for the discrimination of infection severity.

Developing a Tool for Differentiation Between Bacterial and Viral Respiratory Infections Using Myxovirus Resistance Protein A and C-Reactive Protein.

INTRODUCTION: The aim was to assess the performance of a blood assay combining measurements of MxA (myxovirus resistance protein A) and CRP (C-reactive protein) to differentiate viral from bacterial respiratory infections. METHODS: In a prospective study, MxA and CRP were measured in the blood by the AFIAS panel in adults admitted with respiratory infection. Patients were split into discovery and validation cohorts. Final diagnosis was adjudicated by a panel of experts. Microbiology-confirmed cases comprised the discovery cohort, and infections adjudicated as highly probable viral or bacterial comprised the validation cohort. RESULTS: A total of 537 patients were analyzed: 136 patients were adjudicated with definitive viral infections and 131 patients with definitive bacterial infections. Using logistic regression analysis, an equation was developed to calculate the probability for bacterial infection using the absolute value of MxA and CRP. Calculated probability ≥ 0.5 and/or MxA to CRP ratio less than 2 applied as the diagnostic rule for bacterial infections. This rule provided 91.6% sensitivity and 90.4% negative predictive value for the diagnosis of bacterial infections. This diagnostic sensitivity was confirmed in the validation cohort. A MxA/CRP ratio less than 0.15 was associated with unfavorable outcome. CONCLUSION: The calculation of the probability for bacterial infection using MxA and CRP may efficiently discriminate between viral and bacterial respiratory infections.

Interferon-gamma driven elevation of CXCL9: a new sepsis endotype independently associated with mortality.

BACKGROUND: Endotype classification becomes the cornerstone of understanding sepsis pathogenesis. Macrophage activation-like syndrome (MALS) and immunoparalysis are the best recognized major endotypes, so far. Interferon-gamma (IFNγ) action on tissue macrophages stimulates the release of the cytotoxic chemokine CXCL9. It was investigated if this mechanism may be an independent sepsis endotype. METHODS: In this cohort study, 14 patient cohorts from Greece, Germany and Italy were studied. The cohorts were 2:1 randomly split into discovery and validation sets. Sepsis was defined by the Sepsis-3 definitions and blood was sampled the first 24 h from meeting the Sepsis-3 definitions. Concentrations of IFNγ, CXCL9, IP-10 (IFNγ induced protein-10), soluble CD163 and ferritin were measured. The endotype of IFNγ-driven sepsis (IDS) was defined in the discovery set as the combination of a) blood IFNγ above a specified cut-off associated with the minimal risk for immunoparalysis (defined as ≥8000 HLA-DR receptors on CD45/CD14-monoytes); and b) increase of CXCL9. Results were compared to the validation set. FINDINGS: 5503 patients were studied; 3670 in the discovery set and 1833 in the validation set. IDS was defined as IFNγ more than 3 pg/ml and CXCL9 more than 2200 pg/ml. The frequency of IDS in the discovery set was 19.9% (732 patients; 95% confidence intervals-CIs 18.7-21.3%) and in the validation set 20.0% (366 patients; 95% CIs 18.2-21.9%). Soluble CD163, a marker of macrophage activation, was greater in IDS and IDS had features distinct from MALS. The mortality in IDS patients was 43.0% (315 patients; 95% CIs 39.5-46.6%) in the discovery set and 40.4% in the validation set (148 patients; 95% CIs 35.5-45.5%) (p = 0.44 compared to patients of the discovery set). IDS was an independent risk factor for death in the presence of other endotypes, severity scores and organ dysfunctions of the multivariate model [hazard ratio 1.71 (95% CIs 1.45-2.01) in the discovery set and 1.70 (95% CIs 1.34-2.16) in the validation set]. Decreases of IFNγ and CXCL9 blood levels within the first 72 h were associated with better outcome. INTERPRETATION: IDS is a new sepsis endotype independently associated with unfavorable outcome. FUNDING: Hellenic Institute for the Study of Sepsis; Horizon 2020 project ImmunoSep; Swedish Orphan BioVitrum AB (publ) and German Federal Ministry of Education and Research.

An animal model of limitation of gut colonization by carbapenemase-producing Klebsiella pneumoniae using rifaximin.

Current knowledge suggests that infection by carbapenem-resistant enterobacteria is preceded by gut colonization. It is hypothesized that colonization is eradicated by non-absorbable antibiotics like rifaximin. We investigated the effect of rifaximin against carbapenem-resistant Klebsiella pneumoniae (CRKP) in vitro and in a mouse model. We studied the in vitro efficacy of rifaximin against 257 CRKP clinical isolates, 188 KPC producers and 69 OXA-48 producers, by minimum inhibitory concentration and time-kill assays. We then developed a model of gut colonization by feeding 30 C57Bl6 mice with 108 cfu of one KPC-KP isolate for 7 days; mice were pre-treated orally with saline, omeprazole or ampicillin. Then, another 60 mice with established KPC-2 gut colonization received orally for 7 consecutive days rifaximin 180 mg/kg dissolved in ethanol and 4% bile or vehicle. On days 0, 3 and 7 stool samples were collected; mice were sacrificed for determination of tissue outgrowth. At a concentration of 1000 µg/ml rifaximin inhibited 84.8% of CRKP isolates. Α 3 × log10 decrease of the starting inoculum was achieved by 100, 250 and 500 µg/ml of rifaximin after 24 h against 25, 55 and 55% of isolates. Pre-treatment with ampicillin was necessary for gut colonization by KPC-KP. Treatment with rifaximin succeeded in reducing KPC-KP load in stool and in the intestine. Rifaximin inhibits at clinically meaningful gut concentrations the majority of CRKP isolates and is efficient against gut colonization by KPC-KP.

BioFire® FilmArray® Pneumonia Panel for Severe Lower Respiratory Tract Infections: Subgroup Analysis of a Randomized Clinical Trial.

INTRODUCTION: The epidemiology of severe lower respiratory tract infections (LRTI) is constantly changing. We aimed to describe it using the BioFire® FilmArray® Pneumonia plus (PNplus) Panel. METHODS: In a sub-study of the PROGRESS trial, sputum samples of 90 patients with sepsis and LRTI were retrospectively studied. The primary endpoint was the comparative detection rate of pathogens between conventional microbiology and PNplus Panel; secondary endpoints were microbiology and the association with the inflammatory host response. RESULTS: Fifty-six patients with community-acquired pneumonia without risk factors for multidrug-resistant (MDR) pathogens and another 34 patients with risk factors for MDR were studied; median pneumonia severity index (PSI) was 113 (88-135). PNplus detection rate was 72.2% compared to 10% by conventional microbiology (p < 0.001); Streptococcus pneumoniae was the most common pathogen. PSI and procalcitonin were greater among patients with bacterial pathogens than viral pathogens. Median procalcitonin was 0.49 ng/ml and 0.18 ng/ml among patients with ≥ 105 and < 105 copies/ml of detected bacteria, respectively (p = 0.004). Resistance reached 14.4%. CONCLUSION: PNplus detects severe pneumonia pathogens at a greater rate than conventional microbiology. High levels of inflammation accompany bacterial detection. TRIAL REGISTRATION: PROGRESS, ClinicalTrials.gov NCT03333304, 06/11/2017.

Early Start of Oral Clarithromycin Is Associated with Better Outcome in COVID-19 of Moderate Severity: The ACHIEVE Open-Label Single-Arm Trial.

INTRODUCTION: The anti-inflammatory effect of macrolides prompted the study of oral clarithromycin in moderate COVID-19. METHODS: An open-label non-randomized trial in 90 patients with COVID-19 of moderate severity was conducted between May and October 2020. The primary endpoint was defined at the end of treatment (EOT) as no need for hospital re-admission and no progression into lower respiratory tract infection (LRTI) for patients with upper respiratory tract infection and as at least 50% decrease of the respiratory symptoms score without progression into severe respiratory failure (SRF) for patients with LRTI. Viral load, biomarkers, the function of mononuclear cells and safety were assessed. RESULTS: The primary endpoint was attained in 86.7% of patients treated with clarithromycin (95% CIs 78.1-92.2%); this was 91.7% and 81.4% among patients starting clarithromycin the first 5 days from symptoms onset or later (odds ratio after multivariate analysis 6.62; p 0.030). The responses were better for patients infected by non-B1.1 variants. Clarithromycin use was associated with decreases in circulating C-reactive protein, tumour necrosis factor-alpha and interleukin (IL)-6; by increase of production of interferon-gamma and decrease of production of interleukin-6 by mononuclear cells; and by suppression of SARS-CoV-2 viral load. No safety concerns were reported. CONCLUSIONS: Early clarithromycin treatment provides most of the clinical improvement in moderate COVID-19. TRIAL REGISTRATION: ClinicalTrials.gov, NCT04398004.

Early treatment of COVID-19 with anakinra guided by soluble urokinase plasminogen receptor plasma levels: a double-blind, randomized controlled phase 3 trial.

Early increase of soluble urokinase plasminogen activator receptor (suPAR) serum levels is indicative of increased risk of progression of coronavirus disease 2019 (COVID-19) to respiratory failure. The SAVE-MORE double-blind, randomized controlled trial evaluated the efficacy and safety of anakinra, an IL-1α/ß inhibitor, in 594 patients with COVID-19 at risk of progressing to respiratory failure as identified by plasma suPAR ≥6 ng ml-1, 85.9% (n = 510) of whom were receiving dexamethasone. At day 28, the adjusted proportional odds of having a worse clinical status (assessed by the 11-point World Health Organization Clinical Progression Scale (WHO-CPS)) with anakinra, as compared to placebo, was 0.36 (95% confidence interval 0.26-0.50). The median WHO-CPS decrease on day 28 from baseline in the placebo and anakinra groups was 3 and 4 points, respectively (odds ratio (OR) = 0.40, P < 0.0001); the respective median decrease of Sequential Organ Failure Assessment (SOFA) score on day 7 from baseline was 0 and 1 points (OR = 0.63, P = 0.004). Twenty-eight-day mortality decreased (hazard ratio = 0.45, P = 0.045), and hospital stay was shorter.

Serum Hydrogen Sulfide and Outcome Association in Pneumonia by the SARS-CoV-2 Coronavirus.

BACKGROUND: The pneumonia of COVID-19 illness has often a subtle initial presentation making mandatory the use of biomarkers for evaluation of severity and prediction of final patient disposition. We evaluated the use of hydrogen sulfide (H2S) for the outcome of COVID-19 pneumonia. PATIENTS AND METHODS: We studied 74 patients with COVID-19. Clinical data were collected, and survival predictors were calculated. Blood was collected within 24 h after admission (day 1) and on day 7. H2S was measured in sera by monobromobimane derivation followed by high-performance liquid chromatography and correlated to other markers like procalcitonin and C-reactive protein (CRP). Tumor necrosis factor alpha and interleukin (IL)-6 were also measured in serum. RESULTS: Survivors had significantly higher H2S levels on days 1 and 7 after admission. A cut-off point of 150.44 µM could discriminate survivors from non-survivors with 80% sensitivity, 73.4% specificity, and negative predictive value 95.9%. Mortality after 28 days was 32% with admission levels lower than or equal to 150.44 µM and 4.1% with levels above 150.44 µM (P: 0.0008). Mortality was significantly greater among patients with a decrease of H2S levels from day 1 to day 7 greater than or equal to 36% (p: 0.0005). Serum H2S on day 1 was negatively correlated with IL-6 and CRP and positively correlated with the absolute lymphocyte count in peripheral blood. CONCLUSION: It is concluded that H2S is a potential marker for severity and final outcome of pneumonia by the SARS-CoV-2 coronavirus. Its correlation with IL-6 suggests anti-inflammatory properties.

Complex Immune Dysregulation in COVID-19 Patients with Severe Respiratory Failure.

Proper management of COVID-19 mandates better understanding of disease pathogenesis. The sudden clinical deterioration 7-8 days after initial symptom onset suggests that severe respiratory failure (SRF) in COVID-19 is driven by a unique pattern of immune dysfunction. We studied immune responses of 54 COVID-19 patients, 28 of whom had SRF. All patients with SRF displayed either macrophage activation syndrome (MAS) or very low human leukocyte antigen D related (HLA-DR) expression accompanied by profound depletion of CD4 lymphocytes, CD19 lymphocytes, and natural killer (NK) cells. Tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) production by circulating monocytes was sustained, a pattern distinct from bacterial sepsis or influenza. SARS-CoV-2 patient plasma inhibited HLA-DR expression, and this was partially restored by the IL-6 blocker Tocilizumab; off-label Tocilizumab treatment of patients was accompanied by increase in circulating lymphocytes. Thus, the unique pattern of immune dysregulation in severe COVID-19 is characterized by IL-6-mediated low HLA-DR expression and lymphopenia, associated with sustained cytokine production and hyper-inflammation.