Clinical and molecular epidemiological features of critically ill patients with invasive group A Streptococcus infections: a Belgian multicenter case-series

BACKGROUND

Recent alerts have highlighted an increase in group A streptococcal (GAS) infections since 2022 in Europe and the United States. Streptococcus pyogenes can cause limited skin or mucosal disease, but can also present as severe invasive disease necessitating critical care. We performed a multicenter retrospective study of patients with GAS infections recently admitted to Belgian intensive care units (ICUs) since January 2022. We describe patient characteristics and investigate the molecular epidemiology of the S. pyogenes strains involved.

RESULTS

Between January 2022 and May 2023, a total of 86 cases (56 adults, 30 children) with GAS disease were admitted to critical care in the university hospitals of Leuven, Antwerp and Liège. We noted a strikingly high incidence of severe community-acquired pneumonia (sCAP) (45% of adults, 77% of children) complicated with empyema in 45% and 83% of adult and pediatric cases, respectively. Two-thirds of patients with S. pyogenes pneumonia had viral co-infection, with influenza (13 adults, 5 children) predominating. Other disease presentations included necrotizing fasciitis (23% of adults), other severe skin/soft tissue infections (16% of adults, 13% of children) and ear/nose/throat infections (13% of adults, 13% of children). Cardiogenic shock was frequent (36% of adults, 20% of children). Fifty-six patients (65%) had toxic shock syndrome. Organ support requirements were high and included invasive mechanical ventilation (77% of adults, 50% of children), renal replacement therapy (29% of adults, 3% of children) and extracorporeal membrane oxygenation (20% of adults, 7% of children). Mortality was 21% in adults and 3% in children. Genomic analysis of S. pyogenes strains from 55 out of 86 patients showed a predominance of emm1 strains (73%), with a replacement of the M1global lineage by the toxigenic M1UK lineage (83% of emm1 strains were M1UK).

CONCLUSIONS

The recent rise of severe GAS infections (2022-23) is associated with introduction of the M1UK lineage in Belgium, but other factors may be at play-including intense circulation of respiratory viruses and potentially an immune debt after the COVID pandemic. Importantly, critical care physicians should include S. pyogenes as causative pathogen in the differential diagnosis of sCAP.

ESPEN practical and partially revised guideline: Clinical nutrition in the intensive care unit

Following the new ESPEN Standard Operating Procedures, the previous 2019 guideline to provide best medical nutritional therapy to critically ill patients has been shortened and partially revised. Following this update, we propose this publication as a practical guideline based on the published scientific guideline, but shortened and illustrated by flow charts. The main goal of this practical guideline is to increase understanding and allow the practitioner to implement the Nutrition in the ICU guidelines. All the items discussed in the previous guidelines are included as well as special conditions.

Development and validation of the creatinine clearance predictor machine learning models in critically ill adults

BACKGROUND

In critically ill patients, measured creatinine clearance (CrCl) is the most reliable method to evaluate glomerular filtration rate in routine clinical practice and may vary subsequently on a day-to-day basis. We developed and externally validated models to predict CrCl one day ahead and compared them with a reference reflecting current clinical practice.

METHODS

A gradient boosting method (GBM) machine-learning algorithm was used to develop the models on data from 2825 patients from the EPaNIC multicenter randomized controlled trial database. We externally validated the models on 9576 patients from the University Hospitals Leuven, included in the M@tric database. Three models were developed: a "Core" model based on demographic, admission diagnosis, and daily laboratory results; a "Core + BGA" model adding blood gas analysis results; and a "Core + BGA + Monitoring" model also including high-resolution monitoring data. Model performance was evaluated against the actual CrCl by mean absolute error (MAE) and root-mean-square error (RMSE).

RESULTS

All three developed models showed smaller prediction errors than the reference. Assuming the same CrCl of the day of prediction showed 20.6 (95% CI 20.3-20.9) ml/min MAE and 40.1 (95% CI 37.9-42.3) ml/min RMSE in the external validation cohort, while the developed model having the smallest RMSE (the Core + BGA + Monitoring model) had 18.1 (95% CI 17.9-18.3) ml/min MAE and 28.9 (95% CI 28-29.7) ml/min RMSE.

CONCLUSIONS

Prediction models based on routinely collected clinical data in the ICU were able to accurately predict next-day CrCl. These models could be useful for hydrophilic drug dosage adjustment or stratification of patients at risk.

TRIAL REGISTRATION

Not applicable.

Development and validation of clinical prediction models for acute kidney injury recovery at hospital discharge in critically ill adults

PURPOSE

Acute kidney injury (AKI) recovery prediction remains challenging. The purpose of the present study is to develop and validate prediction models for AKI recovery at hospital discharge in critically ill patients with ICU-acquired AKI stage 3 (AKI-3).

METHODS

Models were developed and validated in a development cohort (n = 229) and a matched validation cohort (n = 244) from the multicenter EPaNIC database to create prediction models with the least absolute shrinkage and selection operator (Lasso) machine-learning algorithm. We evaluated the discrimination and calibration of the models and compared their performance with plasma neutrophil gelatinase-associated lipocalin (NGAL) measured on first AKI-3 day (NGAL_AKI3) and reference model that only based on age.

RESULTS

Complete recovery and complete or partial recovery occurred in 33.20% and 51.23% of the validation cohort patients respectively. The prediction model for complete recovery based on age, need for renal replacement therapy (RRT), diagnostic group (cardiac/surgical/trauma/others), and sepsis on admission had an area under the receiver operating characteristics curve (AUROC) of 0.53. The prediction model for complete or partial recovery based on age, need for RRT, platelet count, urea, and white blood cell count had an AUROC of 0.61. NGAL_AKI3 showed AUROCs of 0.55 and 0.53 respectively. In cardiac patients, the models had higher AUROCs of 0.60 and 0.71 than NGAL_AKI3's AUROCs of 0.52 and 0.54. The developed models demonstrated a better performance over the reference models (only based on age) for cardiac surgery patients, but not for patients with sepsis and for a general ICU population.

CONCLUSION

Models to predict AKI recovery upon hospital discharge in critically ill patients with AKI-3 showed poor performance in the general ICU population, similar to the biomarker NGAL. In cardiac surgery patients, discrimination was acceptable, and better than NGAL. These findings demonstrate the difficulty of predicting non-reversible AKI early.

A guide to enteral nutrition in intensive care units: 10 expert tips for the daily practice

The preferential use of the oral/enteral route in critically ill patients over gut rest is uniformly recommended and applied. This article provides practical guidance on enteral nutrition in compliance with recent American and European guidelines. Low-dose enteral nutrition can be safely started within 48 h after admission, even during treatment with small or moderate doses of vasopressor agents. A percutaneous access should be used when enteral nutrition is anticipated for ≥ 4 weeks. Energy delivery should not be calculated to match energy expenditure before day 4–7, and the use of energy-dense formulas can be restricted to cases of inability to tolerate full-volume isocaloric enteral nutrition or to patients who require fluid restriction. Low-dose protein (max 0.8 g/kg/day) can be provided during the early phase of critical illness, while a protein target of > 1.2 g/kg/day could be considered during the rehabilitation phase. The occurrence of refeeding syndrome should be assessed by daily measurement of plasma phosphate, and a phosphate drop of 30% should be managed by reduction of enteral feeding rate and high-dose thiamine. Vomiting and increased gastric residual volume may indicate gastric intolerance, while sudden abdominal pain, distension, gastrointestinal paralysis, or rising abdominal pressure may indicate lower gastrointestinal intolerance.

Monocyte-driven atypical cytokine storm and aberrant neutrophil activation as key mediators of COVID-19 disease severity

Epidemiological and clinical reports indicate that SARS-CoV-2 virulence hinges upon the triggering of an aberrant host immune response, more so than on direct virus-induced cellular damage. To elucidate the immunopathology underlying COVID-19 severity, we perform cytokine and multiplex immune profiling in COVID-19 patients. We show that hypercytokinemia in COVID-19 differs from the interferon-gamma-driven cytokine storm in macrophage activation syndrome, and is more pronounced in critical versus mild-moderate COVID-19. Systems modelling of cytokine levels paired with deep-immune profiling shows that classical monocytes drive this hyper-inflammatory phenotype and that a reduction in T-lymphocytes correlates with disease severity, with CD8+ cells being disproportionately affected. Antigen presenting machinery expression is also reduced in critical disease. Furthermore, we report that neutrophils contribute to disease severity and local tissue damage by amplification of hypercytokinemia and the formation of neutrophil extracellular traps. Together our findings suggest a myeloid-driven immunopathology, in which hyperactivated neutrophils and an ineffective adaptive immune system act as mediators of COVID-19 disease severity.

Prevalence of hypophosphatemia in the ICU - Results of an international one-day point prevalence survey

BACKGROUND & AIMS

Hypophosphatemia (HypoP) is associated with organ dysfunction and mortality. Despite its potential severe consequences, HypoP remains poorly characterized in terms of real prevalence and timing of onset. The primary objective was to determine the prevalence of HypoP defined as blood phosphate <0.8 and < 0.65 mmol/l on one particular day at international level.

METHODS

One-day point prevalence survey conducted by the Section of Metabolism, Endocrinology and Nutrition (MEN) of the European Society of Intensive Care Medicine (ESICM) during week 11-2020.

RESULTS

In total, 56 adult and 4 paediatric ICUs, from 22 countries participated: 41 ICUs were mixed medico surgical, the 19 others being cardiac, medical or surgical. Phosphate measurements were performed daily in 21 ICUs, and 1-3 times per week in 39 ICUs. On D-Day 909 patients (883 adults) were present and 668/883 (75.7%) had serum/plasma phosphate determined, revealing a HypoP in 103 (15.4%) patients aged 62 [18 to 85] years. Of those, 49 patients presented phosphate <0.65 mmol/l: cases of hypophosphatemia were detected at any time of patient's ICU stay. No HypoP was observed in children. A treatment protocol existed only in 41.1% of adult ICUs, independently of ICU type, or size. Only 41/98 of the HypoP patients (29/41 of patients with phosphate <0.65 mmol/l) were receiving phosphate.

CONCLUSION

HypoP is present at least in 15.4% of ICU patients, and may occur at any time during the ICU stay. The absence of phosphate repletion protocols in 60% of participating ICUs is an unexpected finding, and confirms the necessity for the development of ICU phosphate protocols and guidelines.

CLINICALTRIALS IDENTIFIER

NCT04201899.

Early neuromuscular electrical stimulation reduces the loss of muscle mass in critically ill patients - A within subject randomized controlled trial

PURPOSE

To investigate the effect of Neuromuscular Electrical Stimulation (NMES) on muscle thickness, strength and morphological and molecular markers of the quadriceps.

MATERIALS AND METHODS

Adult critically ill patients with an expected prolonged stay received unilateral quadriceps NMES sessions for 7 consecutive days. Before and after the intervention period, quadriceps thickness was measured with ultrasound. After the intervention period, strength was assessed in cooperative patients and muscle biopsies were taken. Multivariable regression was performed to identify factors affecting muscle thickness loss.

RESULTS

Muscle thickness decreased less in the stimulated leg (-6 ± 16% versus -12 ± 15%, p = 0.014, n = 47). Strength was comparable. Opioid administration, minimal muscle contraction and more muscle thickness loss in the non-stimulated muscle were independently associated with better muscle thickness preservation. Stimulated muscles showed a shift towards larger myofibers and higher MyHC-I gene expression. NMES did not affect gene expression of other myofibrillary proteins, MuRF-1 or atrogin-1. Signs of myofiber necrosis and inflammation were comparable for both muscles.

CONCLUSIONS

NMES attenuated the loss of muscle mass, but not of strength, in critically ill patients. Preservation of muscle mass was more likely in patients receiving opioids, patients with a minimal muscle contraction during NMES and patients more prone to lose muscle mass.

TRIAL REGISTRATION

clinicaltrials.govNCT02133300.

Severe Adverse Reaction to Vemurafenib in a Pregnant Woman with Metastatic Melanoma

Targeted therapies have drastically changed the management of metastatic melanoma and have shown encouraging results on tumour progression but are also known for their high rates of adverse reactions. In general, targeted therapies are contraindicated during pregnancy due to concerns about teratogenesis. For the BRAF V600 inhibitor vemurafenib, the available literature about the effects on human pregnancy is limited to a single case report. In patients with metastatic melanoma that wish to continue their pregnancy, targeted therapies like vemurafenib offer the only possibility of improving maternal outcome. In this article, we report on a pregnant woman with metastatic melanoma who was treated with vemurafenib during pregnancy and experienced a fatal adverse reaction.

Withholding parenteral nutrition during critical illness increases plasma bilirubin but lowers the incidence of biliary sludge

Cholestatic liver dysfunction (CLD) and biliary sludge often occur during critical illness and are allegedly aggravated by parenteral nutrition (PN). Delaying initiation of PN beyond day 7 in the intensive care unit (ICU) (late PN) accelerated recovery as compared with early initiation of PN (early PN). However, the impact of nutritional strategy on biliary sludge and CLD has not been fully characterized. This was a preplanned subanalysis of a large randomized controlled trial of early PN versus late PN (n = 4,640). In all patients plasma bilirubin (daily) and liver enzymes (alanine aminotransferase [ALT], aspartate aminotransferase [AST], gamma-glutamyl transpeptidase [GGT], alkaline phosphatase [ALP], twice weekly; n = 3,216) were quantified. In a random predefined subset of patients, plasma bile acids (BAs) were also quantified at baseline and on days 3, 5, and last ICU-day (n = 280). Biliary sludge was ultrasonographically evaluated on ICU-day 5 (n = 776). From day 1 after randomization until the end of the 7-day intervention window, bilirubin was higher in the late PN than in the early PN group (P < 0.001). In the late PN group, as soon as PN was started on day 8 bilirubin fell and the two groups became comparable. Maximum levels of GGT, ALP, and ALT were lower in the late PN group (P < 0.01). Glycine/taurine-conjugated primary BAs increased over time in ICU (P < 0.01), similarly for the two groups. Fewer patients in the late PN than in the early PN group developed biliary sludge on day 5 (37% versus 45%; P = 0.04).

CONCLUSION

Tolerating substantial caloric deficit by withholding PN until day 8 of critical illness increased plasma bilirubin but reduced the occurrence of biliary sludge and lowered GGT, ALP, and ALT. These results suggest that hyperbilirubinemia during critical illness does not necessarily reflect cholestasis and instead may be an adaptive response that is suppressed by early PN.

Gallbladder wall sonolucency in acute cholecystitis

The usual ultrasound findings in acute cholecystitis include diffuse hyperreflective wall thickening, hazy wall delineation and gallbladder distension. In 11 patients with acute cholecystitis, an additional sign was seen consisting of a hyporeflective or sonolucent layer, continuous or interrupted, within the hyperreflective, thickened gallbladder wall. Anatomic-pathologic correlation, comparative CT scans and clinical follow-up studies showed subserosal edema and necrosis to be the most probable cause of this finding.