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.

Acquired agitation in acute respiratory distress syndrome with COVID-19 compared to influenza patients: a propensity score matching observational study.

BACKGROUND: A growing body of evidence reports that agitation and encephalopathy are frequent in critically ill Covid-19 patients. We aimed to assess agitation's incidence and risk factors in critically ill ARDS patients with Covid-19. For that purpose, we compared SARS-CoV-2 acute respiratory distress syndrome (ARDS) patients with a population of influenza ARDS patients, given that the influenza virus is also known for its neurotropism and ability to induce encephalopathy. METHODS: We included all the patients with laboratory-confirmed Covid-19 infection and ARDS admitted to our medical intensive care unit (ICU) between March 10th, 2020 and April 16th, 2021, and all the patients with laboratory-confirmed influenza infection and ARDS admitted to our ICU between April 10th, 2006 and February 8th, 2020. Clinical and biological data were prospectively collected and retrospectively analyzed. We also recorded previously known factors associated with agitation (ICU length of stay, length of invasive ventilation, SOFA score and SAPS II at admission, sedative and opioids consumption, time to defecation). Agitation was defined as a day with Richmond Agitation Sedation Scale greater than 0 after exclusion of other causes of delirium and pain. We compared the prevalence of agitation among Covid-19 patients during their ICU stay and in those with influenza patients. RESULTS: We included 241 patients (median age 62 years [53-70], 158 males (65.5%)), including 146 patients with Covid-19 and 95 patients with Influenza. One hundred eleven (46.1%) patients had agitation during their ICU stay. Patients with Covid-19 had significantly more agitation than patients with influenza (respectively 80 patients (54.8%) and 31 patients (32.6%), p < 0.01). After matching with a propensity score, Covid-19 patients remained more agitated than influenza patients (49 (51.6% vs 32 (33.7%), p = 0.006). Agitation remained independently associated with mortality after adjustment for other factors (HR = 1.85, 95% CI 1.37-2.49, p < 0.001). CONCLUSION: Agitation in ARDS Covid-19 patients was more frequent than in ARDS influenza patients and was not associated with common risk factors, such as severity of illness or sedation. Systemic hyperinflammation might be responsible for these neurological manifestations, but there is no specific management to our knowledge.

Tolerance and complications of therapeutic plasma exchange by centrifugation: A single center experience.

INTRODUCTION: Therapeutic plasma exchange (TPE) constitutes an important therapy for hematological, neurological, immunological, and nephrological diseases. Most studies have focused on efficacy, whereas tolerance and complications during sessions have been less well studied and not recently. MATERIAL AND METHODS: We conducted a single center retrospective study of all patients who underwent TPE between 2011 and 2018. TPE sessions using the centrifugation technique were performed by dedicated trained nurses. Specific side effects were identified through surveillance forms completed contemporaneously. The primary outcome was the rate of all-type adverse effects that occurred during the TPE sessions. RESULTS: In total, 1895 TPE sessions performed on 185 patients were analyzed. At least one adverse effect was reported for 805 sessions (42.5% [29.9%-70.1%]), corresponding to 171 patients (92.4% [87.6%-95.8%]). Hypotension occurred during 288 sessions (15.2%), was asymptomatic in 95.8% of cases, and more frequent with the use of 4% albumin than fresh frozen plasma (FFP) (19.8 vs 8.9%, P <.0001). Hypocalcemia occurred during 370 sessions (19.6%) and was more frequent with the use of FFP than with the use of albumin alone (FFP alone: 28.0%, albumin + FFP: 26%, albumin alone: 11.7%; P <.0001). Allergic reactions occurred during 56 sessions (3%), exclusively with FFP. Severe adverse effects were reported for 0.3% of sessions and 5.4% of patients. CONCLUSIONS: TPE is a safe therapy when performed by a trained team. Adverse effects were frequent but mostly not serious. The replacement fluid was the main determinant of the occurrence of complications. (ClinicalTrials.gov ID: NCT03888417).

Neutrophil phenotype, effector functions and microbicidal activity in SARS-CoV-2-associated ARDS patients.

Critically ill patients admitted to the intensive care unit (ICU) for SARS-CoV-2-induced acute respiratory distress syndrome (ARDS) are at increased risk of bacterial and fungal secondary pulmonary infections due to acquired immune dysfunction. Given that the activity of neutrophils has not been described in these patients, we aimed to investigate the function of neutrophils at ICU admission and on Day 7 (D7) post admission. Neutrophil maturation and several functional indicators were investigated. We detected a significant decrease in reactive oxygen species production at D7, but we did not observe any other significant alterations in neutrophil function. Furthermore, bronchoalveolar lavage obtained from patients displayed no inhibitory effect on the function of neutrophils from healthy donors. These findings indicate that patients admitted to the ICU for SARS-CoV-2-induced ARDS do not acquire neutrophil dysfunction within the first week of their stay, which suggests that nosocomial infections among these patients are not due to acquired neutrophil dysfunctions.

Clinical description and outcome of overall varicella-zoster virus-related organ dysfunctions admitted in intensive care units: the VAZOREA cohort study.

BACKGROUND: Due to aging population and increasing part of immunocompromised patients, a raise in life-threatening organ damage related to VZV can be expected. Two retrospective studies were already conducted on VZV in ICU but focused on specific organ injury. Patients with high-risk of VZV disease still must be identified. The objective of this study was to report the clinical features and outcome of all life-threatening VZV manifestations requiring intensive care unit (ICU) admission. This retrospective cohort study was conducted in 26 French ICUs and included all adult patients with any life-threatening VZV-related event requiring ICU admission or occurring in ICU between 2010 and 2019. RESULTS: One-hundred nineteen patients were included with a median SOFA score of 6. One hundred eight patients (90.8%) were admitted in ICU for VZV disease, leaving 11 (9.2%) with VZV disease occurring in ICU. Sixty-one patients (51.3%) were immunocompromised. Encephalitis was the most prominent organ involvement (55.5%), followed by pneumonia (44.5%) and hepatitis (9.2%). Fifty-four patients (45.4%) received norepinephrine, 72 (60.5% of the total cohort) needed invasive mechanical ventilation, and 31 (26.3%) received renal-replacement therapy. In-hospital mortality was 36.1% and was significantly associated with three independent risk factors by multivariable logistic regression: immunosuppression, VZV disease occurring in ICU and alcohol abuse. Hierarchical clustering on principal components revealed five phenotypically distinct clusters of patients: VZV-related pneumonia, mild encephalitis, severe encephalitis in solid organ transplant recipients, encephalitis in other immunocompromised hosts and VZV disease occurring in ICU. In-hospital mortality was highly different across phenotypes, ranging from zero to 75% (p < 0.001). CONCLUSION: Overall, severe VZV manifestations are associated with high mortality in the ICU, which appears to be driven by immunosuppression status rather than any specific organ involvement. Deciphering the clinical phenotypes may help clinicians identify high-risk patients and assess prognosis.

A case report of Covid-19 in an autoimmune pulmonary alveolar proteinosis: An association in tune with the times!

Autoimmune pulmonary alveolar proteinosis (PAP) is a rare disease characterized by the alveoli accumulation of surfactants proteins and lipids, which diagnosis is confirmed by the presence of GM-CSF antibodies in serum. PAP can be evoked when its characteristic images on chest computed-tomography (CT) are present: bilateral and multifocal ground-glass opacities and crazy-paving appearance. Patients with PAP are at an increased risk of opportunistic infections caused by Nocardia, mycobacteria and fungal pathogens due to impaired processing of pulmonary surfactant. We here report a typical case of newly diagnosed autoimmune PAP, with initial indication to realize a whole-lung lavage. Despite this treatment the patient presented a marked clinical worsening, with increasing need for oxygen and finally the need for mechanical ventilation. The chest CT was controlled and found to be typical of PAP, while the search for opportunistic infections remained negative. Finally, SARS-CoV-2 PCR was performed on bronchoalveolar lavage fluid, and was positive, whereas it had previously been negative twice. Our case report highlights the difficulty of distinguishing SARS-CoV-2 infection in the context of PAP, as the chest CT features are similar. We believe that a SARS-CoV-2 RT-PCR should be systematically realized in case of respiratory deterioration in PAP patients.

Impact of Arterial CO2 Retention in Patients With Moderate or Severe ARDS.

BACKGROUND: Lung-protective ventilation (reduced tidal volume and limited plateau pressure) may lead to CO2 retention. Data about the impact of hypercapnia in patients with ARDS are scarce and conflicting. METHODS: We performed a non-interventional cohort study with subjects with ARDS admitted from 2006 to 2021 and with PaO2 /FIO2 ≤ 150 mm Hg. We examined the association between severe hypercapnia (PaCO2 ≥ 50 mm Hg) on the first 5 days after the diagnosis of ARDS and death in ICU for 930 subjects. All the subjects received lung-protective ventilation. RESULTS: Severe hypercapnia was noted in 552 subjects (59%) on the first day of ARDS (day 1); 323/930 (34.7%) died in the ICU. Severe hypercapnia on day 1 was associated with mortality in the unadjusted (odds ratio 1.54, 95% CI 1.16-1.63; P = .003) and adjusted (odds ratio 1.47, 95% CI 1.08-2.43; P = .004) models. In the Bayesian analysis, the posterior probability that severe hypercapnia was associated with ICU death was > 90% in 4 different priors, including a septic prior for this association. Sustained severe hypercapnia on day 5, defined as severe hypercapnia present from day 1 to day 5, was noted in 93 subjects (12%). After propensity score matching, severe hypercapnia on day 5 remained associated with ICU mortality (odds ratio 1.73, 95% CI 1.02-2.97; P = .047). CONCLUSIONS: Severe hypercapnia was associated with mortality in subjects with ARDS who received lung-protective ventilation. Our results deserve further evaluation of the strategies and treatments that aim to control CO2 retention.

Bacterial and fungal infections: a frequent and deadly complication among critically ill acute liver failure patients.

BACKGROUND: Acute liver failure (ALF) is a rare but life-threatening condition mostly requiring intensive care unit (ICU) admission. ALF induces immune disorders and may promote infection acquisition. However, the clinical spectrum and impact on patients' prognosis remain poorly explored. METHODS: We conducted a retrospective single-centre study on patients admitted for ALF to the ICU of a referral University Hospital from 2000 to 2021. Baseline characteristics and outcomes according to the presence of infection until day 28 were analysed. Risk factors for infection were determined using logistic regression. The impact of infection on 28-day survival was assessed using the proportional hazard Cox model. RESULTS: Of the 194 patients enrolled, 79 (40.7%) underwent infection: community-acquired, hospital-acquired before ICU and ICU-acquired before/without and after transplant in 26, 23, 23 and 14 patients, respectively. Most infections were pneumonia (41.4%) and bloodstream infection (38.8%). Of a total of 130 microorganisms identified, 55 were Gram-negative bacilli (42.3%), 48 Gram-positive cocci (36.9%) and 21 were fungi (16.2%). Obesity (OR 3.77 [95% CI 1.18-14.40]; p = .03) and initial mechanical ventilation (OR 2.26 [95% CI 1.25-4.12]; p = .007) were independent factors associated with overall infection. SAPSII > 37 (OR 3.67 [95% CI 1.82-7.76], p < .001) and paracetamol aetiology (OR 2.10 [95% CI 1.06-4.22], p = .03) were independently associated with infection at admission to ICU. On the opposite, paracetamol aetiology was associated with lower risk of ICU-acquired infection (OR 0.37 [95% CI 0.16-0.81], p = .02). Patients with any type of infection had lower day 28 survival rates (57% versus 73%; HR 1.65 [1.01-2.68], p = .04). The presence of infection at ICU admission (p = .04), but not ICU-acquired infection, was associated with decreased survival. CONCLUSIONS: The prevalence of infection is high in ALF patients which is associated with a higher risk of death. Further studies assessing the use of early antimicrobial therapy are needed.

Neutrophil function and bactericidal activity against Staphylococcus aureus after cardiac surgery with cardiopulmonary bypass.

Staphylococcus aureus is the main bacterial pathogen encountered in mediastinitis after cardiac surgical procedures; it remains a devastating complication with a high mortality rate. As neutrophils have a primordial role in the defense against staphylococcus infection and cardiopulmonary bypass (CPB) is known to induce immunosuppression, the aim of this study was to investigate CPB impact on neutrophil functions. Patients without known immunosuppression scheduled for cardiac surgery with CPB were included. Bone marrow and blood samples were harvested before, during, and after surgery. Neutrophil phenotypic maturation and functions (migration, adhesion, neutrophil extracellular trap [NET] release, reactive oxygen species (ROS) production, phagocytosis, and bacteria killing) were investigated. Two types of Staphylococcus aureus strains (one from asymptomatic nasal carriage and another from mediastinitis infected tissues) were used to assess in vitro bacterial direct impact on neutrophils. We found that CPB induced a systemic inflammation with an increase in circulating mature neutrophils after surgery. Bone marrow sample analysis did not reveal any modification of neutrophil maturation during CPB. Neutrophil lifespan was significantly increased and functions such as NET release and ROS production were enhanced after CPB whereas bacteria killing and phagocytosis were not impacted. Results were similar with the two different isolates of Staphylococcus aureus. These data suggest that CPB induces a recruitment of mature neutrophils via a demargination process rather than impacting their maturation in the bone marrow. In addition, neutrophils are fully efficient after CPB and do not contribute to postoperative immunosuppression.

[Troponin T cardiac analysis: clinical cases of the limits of its cardiospecificity]. / Illustrations cliniques d'un manque de cardiospécificité du dosage de troponine T hypersensible.

INTRODUCTION: Myositis are systemic diseases, in which heart damage is possible. Cardiac troponin T is often found to be defective to detect cardiac involvement. OBSERVATION: We report cases of two patients with a myositis. Diagnosis was retained based on muscle pain, increase in serum creatinine kinase, and inflammatory muscle damage on MRI. Histology confirmed the diagnosis for one of the two patients. Cardiac troponin T was measured in both patients, to detect myocardial involvement. Despite a serum elevation of this marker, cardiological assessment remained negative (electrocardiogram, cardiac ultrasound, cardiac MRI). Cardiac troponin I was normal in serum because of the absence of correlation with peripheral muscle involvement. CONCLUSION: Cardiac troponin T is correlated with muscle involvement in patients with myositis. Cardiac troponin I should be preferred because of a better specificity.

Impact of Three Different Algorithms for the Screening of SSc-PAH and Comparison with the Decisions of a Multidisciplinary Team.

BACKGROUND: to compare three existing screening algorithms of pulmonary arterial hypertension (PAH) in systemic sclerosis (SSc) with the results of a multidisciplinary team (MDT) meeting from a tertiary center. METHODS: we conducted a monocentric longitudinal study from 2015 to 2018. All patients with SSc according to LeRoy's classification were eligible. Patients were excluded in the case of missing data required by any of the three screening algorithms. The algorithms were applied for each patient at inclusion. Right heart catheterization (RHC) was performed based on the MDT decision. MDT members were all blinded from the results of the three algorithms regarding RHC recommendations. The RHC recommendations of each algorithm were compared with the MDT decision, and the impact on diagnosis and management was evaluated. RESULTS: 117 SSc patients were consecutively included in the study, and 99 had follow-up data over the three-year duration of the study (10 deaths). Among the 117 patients, the MDT suggested RHC for 16 patients (14%), DETECT algorithm for 28 (24%), ASIG for 48 (41%) and ESC/ERS 2015 for 20 (17%). Among the 16 patients who had RHC, SSc-PAH was diagnosed in seven. Among patients with an initial recommendation of RHC based on at least one algorithm but not according to the MDT meeting, no SSc-PAH was diagnosed during the three-year follow-up. Results were unchanged when the new 2018 definition of PAH was applied instead of the previous definition. CONCLUSION: a MDT approach appears interesting for the screening of SSc-PAH, with a significant reduction of RHC performed in comparison with dedicated algorithms. The specific relevance of a MDT for the management and follow-up of patients with RHC recommended by existing algorithms but with no PAH warrants further studies.

Impact on ICU mortality of moderate alcohol consumption in patients admitted with infection.

PURPOSE: Alcohol dependence is associated with poor prognosis in the intensive care unit (ICU), but it remains uncertain whether moderate alcohol consumption negatively affects the prognosis of critically ill patients admitted with infection. MATERIALS AND METHODS: In a prospective observational cohort study performed in 478 patients admitted with documented infection, mortality at day 28 in the group of abstainers and nontrauma patients with estimated alcohol consumption lower than 100 g/week was compared with that in non-alcohol-dependent patients with estimated alcohol consumption between 100 and 350 g/week. RESULTS: In 97 patients (20%), alcohol consumption was estimated to be over 100 g/week, and in 391 patients (80%), alcohol consumption was estimated to be 100 g/week or less. The pathogens identified did not significantly differ between the two groups of patients. After adjusted analysis, alcohol consumption between 100 and 350 g/week remained significantly associated with mortality at day 28 (hazard ratio (HR): 1.67; 95% confidence interval (CI): 1.01-2.77; p = .04). CONCLUSION: Alcohol consumption between 100 and 350 g/week was independently associated with mortality at day 28. Our results suggest that in critically ill patients admitted with infection, moderate alcohol consumption is associated with a poorer prognosis.

Pulmonary arterial hypertension in four patients treated by leflunomide.

Pulmonary arterial hypertension (PAH) is a rare disorder that can be drug-induced, mostly following treatment by appetite-suppressant drugs. We report four cases of patients who developed PAH following a treatment by leflunomide for rheumatoid arthritis, psoriatic arthritis or undetermined connective tissue disease. All patients described a progressive dyspnea from grade II to IV of NYHA classification; clinical examination found signs of heart failure. PAH was finally diagnosed and confirmed by right heart catheterisation. Haemodynamic explorations found pre-capillary pulmonary hypertension with mean pulmonary arterial pressure above 25mmHg, and pulmonary capillary wedge pressure under 15mmHg. Explorations of this pre-capillary pulmonary hypertension were conducted according to international guidelines: pulmonary or chronic thromboembolic aetiologies were excluded after ventilation/perfusion lung scan and high-resolution computed tomography. All other etiologic explorations were negative. Imputability of leflunomide was finally retained. Leflunomide was stopped for all patients; three of them received specific PAH treatments. A favourable clinical and/or haemodynamic evolution was observed for all patients. The conclusions of the investigations conducted by our pharmacovigilance centre were communicated to the European Medicines Agency, leading to the addition of "pulmonary hypertension" in the paragraph "special warning and precautions of use" of the package leaflet of leflunomide.

Adverse Events and Outcomes of High-volume Plasma Exchange in 50 Acute Liver Failure Patients: A Monocentric Retrospective Real-world Study.

Background and aims: Acute liver failure (ALF) is a condition that mostly requires Intensive Care Unit (ICU) admission and sometimes necessitates emergency liver transplantation. High-volume plasma exchange (HVPE) may improve transplant-free survival (TFS) in ALF. Our study assessed complications of HVPE therapy and outcome in ALF patients. Methods: We conducted a single-center retrospective study of all patients admitted to the ICU for ALF and who underwent HVPE between June 2016 and June 2021. The plasmapheresis technique used was centrifugation, and the volume exchanged was calculated as 15% of the ideal body weight. Dedicated staff prospectively collected clinical adverse effects, while biological data were retrospectively collected. The primary outcome was the rate of severe adverse effects (SAE, defined as severe manifestations of hypotension, allergy, metabolic disturbances or other life-threatening event) that occurred during HVPE sessions. Factors influencing day-21 TFS were also studied. Results: One hundred twenty sessions were performed in 50 patients. The main etiology for ALF was paracetamol (52% of the patients). During the session, hemoglobin, platelet, transaminases, ammonia and bilirubin decreased, coagulation factors increased, and creatinine and lactate remained unchanged. At least one SAE was reported for 32 out of 120 sessions (26.7% [19%-35.5%], mostly severe alkalosis [24/117], hypotension [4/120] and hypocalcemia [4/119]). Arterial pH ≤ 7.43 following HVPE and paracetamol etiology were negatively and positively associated with day-21 TFS, respectively. Conclusion: Severe adverse effects were frequent during HVPE performed for ALF, mainly severe alkalosis, hypotension and hypocalcemia. Post-HVPE, pH and paracetamol etiology were prognosis markers.