Cytokine release syndrome-associated encephalopathy in patients with COVID-19.

BACKGROUND AND PURPOSE: Neurological manifestations in coronavirus disease (COVID)-2019 may adversely affect clinical outcomes. Severe COVID-19 and uremia are risk factors for neurological complications. However, the lack of insight into their pathogenesis, particularly with respect to the role of the cytokine release syndrome (CRS), is currently hampering effective therapeutic interventions. The aims of this study were to describe the neurological manifestations of patients with COVID-19 and to gain pathophysiological insights with respect to CRS. METHODS: In this longitudinal study, we performed extensive clinical, laboratory and imaging phenotyping in five patients admitted to our renal unit. RESULTS: Neurological presentation included confusion, tremor, cerebellar ataxia, behavioral alterations, aphasia, pyramidal syndrome, coma, cranial nerve palsy, dysautonomia, and central hypothyroidism. Notably, neurological disturbances were accompanied by laboratory evidence of CRS. Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) was undetectable in the cerebrospinal fluid (CSF). Hyperalbuminorrachia and increased levels of the astroglial protein S100B were suggestive of blood-brain barrier (BBB) dysfunction. Brain magnetic resonance imaging findings comprised evidence of acute leukoencephalitis (n = 3, one of whom had a hemorrhagic form), cytotoxic edema mimicking ischaemic stroke (n = 1), or normal results (n = 2). Treatment with corticosteroids and/or intravenous immunoglobulins was attempted, resulting in rapid recovery from neurological disturbances in two cases. SARS-CoV2 was undetectable in 88 of the 90 patients with COVID-19 who underwent Reverse Transcription-PCR testing of CSF. CONCLUSIONS: Patients with COVID-19 can develop neurological manifestations that share clinical, laboratory and imaging similarities with those of chimeric antigen receptor T-cell-related encephalopathy. The pathophysiological underpinnings appear to involve CRS, endothelial activation, BBB dysfunction, and immune-mediated mechanisms.

[Evaluation of the interest of procalcitonin in the diagnosis of chorioamnionitis in preterm premature rupture of membranes. An observational and prospective study]. / Évaluation de l'intérêt de la procalcitonine pour le diagnostic de chorioamniotite dans les ruptures prématurées des membranes. Étude prospective observationnelle.

INTRODUCTION: Diagnosis of chorioamnionitis (CA) is difficult because all clinical and biological signs are rarely concordant. According to recent literature, PCT could act as a specific marker of bacterial infection. Our main objective was to assess whether PCT could improve our management of patients with preterm premature rupture of membranes (pPROM), allowing earlier and more specific diagnosis for CA. METHODS: Patients with pPROM from 24 and 34weeks of amenorrhea were included, from November 2013 to October 2014. PCT was collected twice a week, from pPROM until delivery. Obstetricians were blinded from PCT results, in order not to influence the management of the patients. PCT values were then compared to clinical and other biological diagnostic markers (CRP and white blood cells count [WBC]). RESULTS: Thirty patients were included, with 11 cases of histological CA and 5 early-onset neonatal sepsis. With a cut-off value of 0.05ng/mL, the sensitivity of PCT to detect histological CA was 54%, the specificity was 79% and the positive and negative predictive value were respectively 60% and 75%. The positive likelihood ratio was 2.57 and the negative likelihood ratio was 0.58. Using PCT values, our medical decision of foetal extraction would have change in 5 cases (in a wrong way in 3 of them). CONCLUSION: PCT in the diagnostic of CA is not useful in the management of patients.

Compartmentalization of Inflammatory Response Following Gut Ischemia Reperfusion.

OBJECTIVE/BACKGROUND: Gut ischemia reperfusion (IR) is thought to trigger systemic inflammation, multiple organ failure, and death. The aim of this study was to investigate inflammatory responses in blood and in two target organs after gut IR. METHODS: This was a controlled animal study. Adult male Wistar rats were randomized into two groups of eight rats: control group and gut IR group (60 minutes of superior mesenteric artery occlusion followed by 60 minutes of reperfusion). Lactate and four cytokines (tumor necrosis factor-a, interleukin [IL]-1b, IL-6, and IL-10) were measured in mesenteric and systemic blood. The relative gene expression of these cytokines was determined by real time polymerase chain reaction in the gut, liver, and lung. RESULTS: Gut IR significantly increased lactate levels in mesenteric (0.9 ± 0.4 vs. 3.7 ± 1.8 mmol/L; p < .001) and in systemic blood (1.3 ± 0.2 vs. 4.0 ± 0.3 mmol/L; p < .001). Gut IR also increased the levels of four cytokines in mesenteric and systemic blood. IL-6 and IL-10 were the main circulating cytokines; there were no significant differences between mesenteric and systemic cytokine levels. IL-10 was upregulated mainly in the lung,suggesting that this organ could play a major role during gut reperfusion. CONCLUSION: The predominance of IL-10 over other cytokines in plasma and the dissimilar organ responses,especially of the lung, might be a basis for the design of therapies, for example lung protective ventilation strategies, to limit the deleterious effects of the inflammatory cascade. A multi-organ protective approach might involve gut directed therapies, protective ventilation, hemodynamic optimization, and hydric balance.

Chromogranin A-derived peptides are involved in innate immunity.

New endogenous antimicrobial peptides (AMPs) derived from chromogranin A (CgA) are secreted by nervous, endocrine and immune cells during stress. They display antimicrobial activities by lytic effects at micromolar range using a pore-forming mechanism against Gram-positive bacteria, filamentous fungi and yeasts. These AMPs can also penetrate quickly into neutrophils (without lytic effects), where, similarly to "cell penetrating peptides", they interact with cytoplasmic calmodulin, and induce calcium influx via Store Operated Channels therefore triggering neutrophils activation. Staphylococcus aureus and Salmonella enteritis are bacteria responsible for severe infections. We investigated here the effects of S. aureus and S. enteritis bacterial proteases on CgA-derived peptides and evaluated their antimicrobial activities. We showed that the Glu-C protease produced by S. aureus V8 induces the loss of the AMPs antibacterial activities and produces new antifungal peptides. In addition, four antimicrobial CGA-derived peptides (chromofungin, procatestatin, human/bovine catestatin) are degraded when treated with bacterial supernatants from S. aureus and S. enteritis, whereas, cateslytin, the short active form of catestatin, resists to this degradation. Finally, we demonstrate that several antimicrobial CgA-derived peptides are able to act synergistically with antibiotics against bacteria and fungi indicating their roles in innate defense.

Detection of K-Ras mutations in tumour samples of patients with non-small cell lung cancer using PNA-mediated PCR clamping.

Non-small cell lung cancers (NSCLC), in particular adenocarcinoma, are often mixed with normal cells. Therefore, low sensitivity of direct sequencing used for K-Ras mutation analysis could be inadequate in some cases. Our study focused on the possibility to increase the detection of K-Ras mutations in cases of low tumour cellularity. Besides direct sequencing, we used wild-type hybridisation probes and peptide-nucleic-acid (PNA)-mediated PCR clamping to detect mutations at codons 12 and 13, in 114 routine consecutive NSCLC frozen surgical tumours untreated by targeted drugs. The sensitivity of the analysis without or with PNA was 10 and 1% of tumour DNA, respectively. Direct sequencing revealed K-Ras mutations in 11 out of 114 tumours (10%). Using PNA-mediated PCR clamping, 10 additional cases of K-Ras mutations were detected (21 out of 114, 18%, P<0.005), among which five in samples with low tumour cellularity. In adenocarcinoma, K-Ras mutation frequency increased from 7 out of 55 (13%) by direct sequencing to 15 out of 55 (27%) by clamped-PCR (P<0.005). K-Ras mutations detected by these sensitive techniques lost its prognostic value. In conclusion, a rapid and sensitive PCR-clamping test avoiding macro or micro dissection could be proposed in routine analysis especially for NSCLC samples with low percentage of tumour cells such as bronchial biopsies or after neoadjuvant chemotherapy.

Cardio protective effect of glucose-insulin infusion on acute digoxin toxicity in rat.

UNLABELLED: We recently observed a case of digoxin and insulin self-poisoning without cardiac repercussion. We raised the hypothesis that insulin may have a cardio-protective effect in case of digoxin toxicity. We have therefore evaluated the effect of glucose-insulin infusion on mortality and ECG abnormalities during acute digoxin toxicity in rats. Before and after a hyperinsulinemia-euglycemia clamp, rats in glucose-insulin-digoxin (GID) group (n=10) received an intravenous infusion of 12ml/h or 2,5ml/h digoxin (0.25mg/ml) respectively until death occured. Animals receiving digoxin or saline solution intravenously served as control (n=10). ECG recording was performed in all animals over the entire period. Serum insulin and digoxin concentrations were measured by ELISA method after digoxin administration. When digoxin was administered after the clamp, all animals in GID group were alive, whereas 80% of animals in the digoxin group were dead (p<0.001) after 30min. The administration of Digoxin provoked rapid death of rats in the digoxin group in 15+/-12min whereas in GID group the survival period was significantly increased to 38+/-3min (p<0.001). Twenty minutes after digoxin administration, P waves disappeared for 78% of animals in digoxin group while they were present in all rats of GID group (p<0.001). Animal death occurred after a digoxin infusion volume of 7.7+/-0.6ml and 3.0+/-2.4ml in GID and digoxin group respectively (p<0.001). Five minutes after digoxin administration, potassium plasmatic level increased significantly in digoxin group as compared to GID group: 7.1+/-2mmol/l versus 4.4+/-0.4mmol/l (p<0.001). When digoxin was infused before the clamp, 40% of animals in GID group were alive after 180min and the other 60% died after 137+/-40min whereas death of rats in the digoxin group occurred within 80+/-10min (p<0.001). The death of animals was preceded by the P waves disappearing. Thirty minutes after digoxin administration, the potassium plasmatic level increased significantly in the digoxin group as compared to the GID group: 6.9+/-0.5mmol/l versus 4.9+/-0.3mmol/l (p<0.001). At the time of death, both volume of digoxin infusion and serum digoxin concentration were increased in GID group as compared to digoxin group: 5.7+/-1.6ml versus 3.3+/-0.4ml (p<0.001) and 10.7+/-8.3mg/l versus 8.5+/-4.6mg/l. CONCLUSION: Glucose-insulin infusion delayed the abnormalities in cardiac conduction and improved rat survival after acute digoxin toxicity. These results suggest a cardioprotective effect of insulin in case of acute digoxin toxicity.