Zinc and selenium status in critically ill patients according to severity stratification

Plasma and red blood cell concentrations of zinc, copper, selenium and magnesium in the first week of paediatric critical illness

BACKGROUND & AIMS

Critically ill children are at risk of micronutrient deficiencies, which might lead to poor clinical outcomes. However, the interpretation of micronutrient concentrations in plasma is complicated due to age-dependent and critical illness-dependent changes. Certain red blood cell (RBC) concentrations might reflect the overall body status more reliably than plasma levels in the presence of systemic inflammatory response. This study longitudinally examined micronutrient concentrations in both plasma and RBC in critically ill children.

METHODS

This secondary analysis of the PEPaNIC RCT investigated the impact of early versus late initiation of parenteral macronutrient supplementation in critically ill children. All children received micronutrients when EN was insufficient (<80 % energy requirements). Blood samples were obtained on days 1, 3, 5 and 7 of Paediatric Intensive Care Unit (PICU) admission. Inductively coupled plasma mass spectrometry was used to measure zinc, selenium, and copper in plasma and selenium, copper, and magnesium in RBCs. Plasma magnesium was measured with colorimetric detection. Micronutrient concentrations were compared with age-specific reference values in healthy children and expressed using Z-scores. Changes in micronutrient concentrations over time were examined using the Friedman and post hoc Wilcoxon signed-rank tests.

RESULTS

For 67 critically ill children, median (Q1; Q3) age 9.5 (5.5; 13.2) years, PIM3 score -2.3 (-3.1; -0.8), samples were available at various time points during their PICU stay. For 22 patients, longitudinal samples were available. On day 1, the median plasma Z-score for zinc was -5.2 (-5.2; -2.9), copper -1.6 (-2.9; -0.2), selenium -2.6 (-3.8; -1.0), magnesium -0.2 (-1.6; 1.3), and median RBC Z-score for copper was 0.5 (-0.1; 1.3), selenium -0.3 (-1.1; 0.7), magnesium 0.2 (-0.4; 1.3). In the longitudinal analysis, plasma zinc was significantly higher on day 5 (Z-score -3.2 (-4.6; -1.4)) than on day 1 (Z-score -5.2 (-5.2; -3.0), p = 0.032), and plasma magnesium was significantly higher on day 3 (Z-score 1.1 (-0.7; 4.0)) than on day 1 (Z-score -0.3 (-1.6; 0.5), p = 0.018). Plasma copper and selenium remained stable, and the RBC concentrations of all micronutrients remained stable during the first five days.

CONCLUSIONS

Most patients had low plasma zinc, copper and selenium concentrations in the first week of their PICU stay, whereas they had normal to high RBC concentrations. More research is needed to examine the relationships between micronutrients and clinical outcome.

Assessment of trace elements in critically ill patients with systemic inflammatory response syndrome: A systematic review

BACKGROUND

Zinc (Zn), copper (Cu), and selenium (Se) are involved in immune and antioxidant defense. Their role in systemic inflammatory response syndrome (SIRS) treatment and outcomes remains unclear. This systematic review aimed to describe trace element concentrations in different types of biological samples and their relationship with morbidity and mortality in patients with SIRS.

METHODS

Literature was systematically reviewed according to the preferred reporting items for systematic reviews and meta-analyses (PRISMA). The search results were screened and evaluated for eligibility, and data were extracted and summarized in tables and figures.

RESULTS

Most of the 38 included studies evaluated Se (75%), followed by Zn (42%) and Cu (22%). Plasma was the main biological sample evaluated (58%). Thirteen studies found lower plasma/serum concentrations of Zn, Se, and Cu in SIRS patients than in controls upon admission, 11 studies on adults (intensive care unit-ICU) and two in pediatric ICU (PICU). Three ICU studies found no difference in erythrocyte trace element concentrations in patients with SIRS. In all studies, the two main outcomes investigated were organ failure and mortality. In seven ICU studies, patients with lower plasma or serum Zn/Se levels had higher mortality rates. A study conducted in the PICU reported an association between increased Se variation and lower 28-day mortality. In an ICU study, lower erythrocyte selenium levels were associated with higher ICU/hospital mortality, after adjustment. Five ICU studies associated lower plasma/serum Zn/Se levels with higher organ failure scores and one PICU study showed an association between higher erythrocyte Se levels and lower organ dysfunction scores.

CONCLUSION

There was no difference in erythrocyte Se levels in patients with SIRS. Serum/Plasma Zn and serum/plasma/erythrocyte Se are associated with organ dysfunction, mortality, and inflammation. Trace element deficiencies should be diagnosed by erythrocyte, or complementary measurements in the presence of inflammation.

Factors Associated with Interruptions of Enteral Nutrition and the Impact on Macro- and Micronutrient Deficits in ICU Patients

BACKGROUND AND AIM

Feeding interruptions in critical care patients are often unjustified. We aimed to determine the causes, duration, and frequency of enteral nutrition interruptions (ENIs) and to assess macronutrients and antioxidant deficits according to European Society of Parenteral Enteral Nutrition (ESPEN) guidelines.

METHODS

We prospectively enrolled Intensive Care Unit (ICU) patients admitted for more than 48 h with an inability to orally eat from April to December 2019. The type of enteral nutrition, the number of calories administered, the time of feeding initiation, the reasons for delaying feeding, and the causes for ENI were recorded.

RESULTS

81 patients were enrolled, with a median duration of ENIs of 5.2 (3.4-7.4) hours/day. Gastric residual volume (GRV) monitoring-a highly controversial practice-was the most common cause of ENI (median duration 3 (2.3-3) hours/day). The mean energy intake was 1037 ± 281 kcal/day, while 60.5% of patients covered less than 65% of the total energy needs (1751 ± 295 kcal/day, according to mean Body Mass Index (BMI)). The median daily protein intake did not exceed 0.43 ± 0.3 gr/kg/day of the actual body weight (BW), whereas ESPEN recommends 1.3 gr/kg/day for adjusted BW (p < 0.001). The average administration of micronutrients and antioxidants (arginine, selenium, zinc, vitamins) was significantly less than the dietary reference intake (p < 0.01).

CONCLUSION

ENIs lead to substantial caloric, protein, and antioxidant deficits.

The influence of early selenium supplementation on trauma patients: A propensity-matched analysis

Introduction

Oxidative stress is involved in numerous inflammatory diseases, including trauma. Micronutrients, such as selenium (Se), which contribute to antioxidant defense, exhibit low plasma levels during critical illness. This study aimed to investigate the impact of early Se supplementation on trauma patients.

Materials and methods

A total of 6,891 trauma patients were registered at a single medical center from January 2018 to December 2021. Twenty trauma patients with Se supplemented according to the protocol were included in the study group. Subsequently, 1:5 propensity score matching (PSM) analysis was introduced. These patients received 100 mcg three times a day for 5 days. The primary outcome was overall survival (OS); the secondary outcomes were hospital/intensive care unit (ICU) length of stay (LOS), serologic change, ventilator dependence days, and ventilation profile.

Results

The hospital LOS (20.0 ± 10.0 vs. 37.4 ± 42.0 days, p = 0.026) and ICU LOS (6.8 ± 3.6 vs. 13.1 ± 12.6 days, p < 0.006) were significantly shorter in the study group. In terms of serology, improvement in neutrophil, liver function, and C-reactive protein (CRP) level change percentile indicated better outcomes in the study group as well as a better OS rate (100 vs. 83.7%, p = 0.042). Longer ventilator dependence was found to be an independent risk factor for mortality and pulmonary complications in 6,891 trauma patients [odds ratio (OR) = 1.262, 95% confidence interval (CI) = 1.039-1.532, p < 0.019 and OR = 1.178, 95% CI = 1.033-1.344, p = 0.015, respectively].

Conclusion

Early Se supplementation after trauma confers positive results in terms of decreasing overall ICU LOS/hospital LOS and mortality. Organ injury, particularly hepatic insults, and inflammatory status, also recovered better.

Clinical nutrition approach in medical management of COVID-19 hospitalized patients: A narrative review

BACKGROUND

Malnutrition in COVID-19 hospitalized patients is associated with a high-risk condition to increase disease severity and prolonging the recovery period. Therefore, nutritional therapy, including supplements plays a critical role to reduce disease-related complications and the length of hospital stay.

AIM

To review the latest evidence on nutritional management options in COVID-19 hospitalized patients, as well as possibly prescribed supplements. Methods: This review was conducted by considering the latest recommendations, using the guidelines of the American Society of Enteral and Parenteral (ASPEN) and the European Society of Enteral and Parenteral (ESPEN), and searching Web of Science, PubMed/Medline, ISI, and Medline databases. The relevant articles were found using a mix of related mesh terms and keywords. We attempted to cover all elements of COVID-19 hospitalized patients' dietary management. Results: Energy demand in COVID-19 patients is a vital issue. Indirect Calorimetry (IC) is the recommended method to measure resting energy expenditure. However, in the absence of IC, predictive equations may be used. The ratio of administered diet for the macronutrients could be based on the phase and severity of Covid-19 disease. Moreover, there are recommendations for taking micronutrient supplements with known effects on improving the immune system or reducing inflammation. Conclusions: Nutritional treatment of COVID-19 patients in hospitals seems to be an important element of their medical care. Enteral nutrition would be the recommended feeding method for early nutrition support. However, data in the COVID-19 nutritional domain relating to micronutrient supplementation are still fragmentary and disputed, and further study is required.

Relationship of zinc level with pathogenetically significant homeostasis disorders in severely burned patients

The aim of the study was to assess the zinc content and identify the relationship between the concentration of this element and changes in the biochemical status of patients and markers of inflammation during burn shock. We examined 23 patients aged 45.3±16.1 years with burns of I-II-III degree, area of 31-80%. The serum concentrations of zinc, albumin, interleukin-6, C-reactive protein (CRP), alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were determined. The majority of patients (21/23) had severe hypocincemia, correlated with burn area (r=-0.53; p=0.008). A decrease in zinc levels during burn shock was associated with the development of hypoalbuminemia (r=0.52, p=0.01). The association of deviations in ALT and AST activity with changes in zinc concentration was revealed (-0.59<γ<-0.61, 0.008<p<0.009), which may indicate the role of hepatic dysfunction in the development of hypocinkemia. The development of a systemic inflammatory response was revealed. The correlation analysis revealed an association between the zinc and interleukin-6 levels (r=-0.63, p=0.03), as well as zinc and CRP (r=-0.41, p=0.04). From the first days after the injury, zinc deficiency is observed in severely burned patients, which is affected by an inflammatory reaction and hypoalbuminemia. Due to the fact that zinc is one of the key factors in maintaining homeostasis in the body, it is necessary to further study the molecular mechanisms of regulating the level of this trace element in burned patients and to develop ways to correct hypocinkemia that contribute to the effective treatment of burn disease.

Selenium Levels and Antioxidant Activity in Critically Ill Patients with Systemic Inflammatory Response Syndrome

The Selenium (Se) status could be an important modifiable factor in critically ill patient outcomes due to the important role of this mineral in several functions. Although there are many clinical trials with Se interventions in the literature, the evidence is not sufficient to establish a common criterion regarding the Se status. Background and aims: An analysis was made of the evolution of selenium (Se) and antioxidant status in critically ill patients with Systemic Inflammatory Response Syndrome (SIRS) over 7 days of staying in the Intensive Care Unit (ICU). Methods: A prospective analytical study was carried out on 65 critically ill patients aged 31−77 years. A healthy control group of 56 volunteers from the same region was recruited to allow comparisons with reference normal values. The selenium levels in both the plasma and erythrocytes were analyzed by Inductively Coupled Plasma Mass Spectrometry (ICP-MS). Glutathione Peroxidase (GPx) and Superoxide Dismutase (SOD) activity and the Total Antioxidant Capacity (TAC) were measured using kinetic colorimetric methods. Results: Low erythrocyte and plasma Se levels were found at ICU admission in comparison with the healthy reference group (p < 0.001), and the levels further decreased after one week (p < 0.001). Smaller changes in the plasma Se levels were associated with greater changes in the Sequential Organ Failure Assessment (SOFA) score (p < 0.05). The GPx activity in the critically ill was lower than in the control group (p < 0.05), with an inverse correlation to the severity scores at the baseline (p < 0.05) and reaching normal values after one week (p < 0.05). SOD activity was directly correlated to TAC (p = 0.03), with both parameters exhibiting a direct correlation to albumin (p < 0.05) after 7 days of ICU stay. Conclusions: A deficient Se status was observed at ICU admission and worsened further over follow-up regardless of the evolution of the patient severity and the antioxidant parameters. Adequate Se support from the start of admission could preserve and contribute to improve the Se-related outcomes and critical patient recovery during longer periods in the ICU.

Serum zinc and copper in people with COVID-19 and zinc supplementation in parenteral nutrition

Objectives

Zinc and copper are important to protect cells from oxidative stress and to enhance immunity. An association between low zinc levels and the severity of acute respiratory distress syndrome has been shown for people with COVID-19. We aimed to study serum zinc and copper concentrations in people with severe COVID-19 and zinc supplementation in parenteral nutrition (PN).

Methods

Thirty-five people with COVID-19 in need of PN were studied in a retrospective design. Serum samples were collected at three time points: at the start of PN, between 3 and 7 d after, and at the end of PN.

Results

Participants were on PN for a mean of 14 d, with a mean (± SD) daily supplemental zinc of 14.8 ± 3.7 mg/d. Serum zinc increased during PN administration from 98.8 ± 22.8 to 114.1 ± 23.3 µg/dL (Wilks’ λ = 0.751, F = 5.459, P = 0.009). Conversely, serum copper did not vary from baseline (107.9 ± 34.2 µg/dL) to the end of the study (104.5 ± 37.4 µg/dL, Wilks’ λ = 0.919, F = 1.453, P = 0.248). Serum zinc within the first week after starting PN and at the end of PN inversely correlated with total hospital stay (r = −0.413, P = 0.014, and r = −0.386, P = 0.022, respectively). Participants in critical condition presented lower serum copper (z = 2.615, P = 0.007). Mortality was not associated with supplemental zinc or with serum zinc or copper concentrations at any time of the study (P > 0.1 for all analyses).

Conclusions

Serum zinc concentrations during PN support were inversely associated with length of hospital stay but not with mortality. Serum copper concentrations were lower in participants in critical condition but not associated with prognosis.

Can selenium-enriched spirulina supplementation ameliorate sepsis outcomes in selenium-deficient animals?

In intensive care units, sepsis is the first cause of death. In this pathology, inflammation and oxidative status play a crucial role in patient outcomes. Interestingly, 92% of septic patients exhibit low selenium plasma concentrations (a component of antioxidant enzymes). Moreover, Spirulina platensis, a blue-green algae, demonstrated anti-inflammatory effects. In this context, the main purpose of our study was to analyze the effect of a selenium-enriched spirulina after a selenium deficiency on sepsis outcome in rats. Sixty-four rats were fed 12 weeks with a selenium-deficient food. After 8 weeks, rats were supplemented (via drinking water) for 4 weeks with sodium selenite (Se), spirulina (Spi), or selenium-enriched spirulina (SeSp). Sepsis was then induced by cecal ligature and puncture, and survival duration was observed. The plasma selenium concentration was measured by ICPMS. Expression of GPx1 and GPx3 mRNA was measured by RT-PCR. Blood parameters (lactates and HCO3- concentrations, pH, PO2 , and PCO2 ) were analyzed at 0, 1, and 2 h as well as inflammatory cytokines (IL-6, TNF-α, IL-10). Sodium selenite and SeSP supplementations restored plasma selenium concentration prior to sepsis. The survival duration of SeSP septic rats was significantly lower than that of selenium-supplemented ones. Gpx1 mRNA was increased after a selenium-enriched spirulina supplementation while Gpx3 mRNA levels remained unchanged. Furthermore, sodium selenite prevented sepsis-induced acidosis. Our results show that on a basis of a Se deficiency, selenium-enriched spirulina supplementations significantly worsen sepsis outcome when compared to Se supplementation. Furthermore, Se supplementation but not selenium-enriched spirulina supplementation decreased inflammation and restored acid-base equilibrium after a sepsis induction.

Beneficial effects of Se/Zn co-supplementation on body weight and adipose tissue inflammation in high-fat diet-induced obese rats

This research investigated the effect of co-supplementation of selenium with zinc on weight control and the inflammatory and oxidative status in relation to obesity. Male Wistar rats (N = 32) were randomly divided into four groups after induction of obesity model: 1) "Zn" was supplemented with zinc sulfate (15 mg/kg BW), 2) "Se" supplemented with selenium as sodium selenate (0.5 mg/kg BW), 3) "Zn + Se" which received Zn (15 mg/kg BW) + Se (0.5 mg/kg BW), and 4) "HFD" as the control group. The intervention was done for eight weeks. At the end of treatment, serum and tissue level of Zn, Se, SOD, GSH-Px, MDA, leptin, TNF-α, and IL-6 was evaluated. Weight and food intake were significantly reduced in the Se group(p < .001), while in the Zn group, weight gain due to obesity was prevented compared to the control group (p = .48). There was a significant and stronger increase in SOD, GSH-Px levels and a remarkable decrease in MDA, leptin, TNF-α, and IL-6 in the group receiving the combination of two supplements than either alone(p < .001). Leptin had a positive correlation with inflammatory factors and lipid peroxidation marker and showed an inverse relationship with Zn and Se levels and anti-oxidative enzymes(p < .05). The analysis showed the mediating role of leptin in the effects of zinc. Co-supplementation of selenium and zinc may have a synergistic effect in reduction of oxidative and inflammatory markers. Regarding the effect of zinc on inflammatory factors and lipid peroxidation, leptin can play a mediating role.

Maternal selenium status plays a crucial role on clinical outcomes of pregnant women with COVID-19 infection

Adequate maternal selenium level is essential for immune response and healthy pregnancy. This study aimed to shed light on the selenium status of pregnant women with COVID-19 and the effects of potential deficiency in serum selenium levels. Totally 141 pregnant women, 71 of them were COVID-19 patients, in different trimesters were included in the study. Maternal serum selenium levels, demographic and clinical parameters were determined. Serum selenium levels of pregnant women in the second (p: .0003) and third (p: .001) trimesters with COVID-19 were significantly lower than in the healthy group. Maternal selenium level was found to be negatively correlated with gestational week (p < .0001, r: -.541), D-dimer (p: .0002, r: -.363) and interleukin-6 (IL-6) level (p: .02, r: -.243). In the second trimester, serum selenium level positively correlated with white blood cell (p: .002, r: .424), neutrophil (p: .006, r: .39), lymphocyte (p: .004, r: .410) count and hemoglobin (p: .02, r: .323), hematocrit (p: .008, r: .38) status. In the third trimester, it was found that maternal selenium level positively correlated with monocyte (p: .04, r: .353) and negatively correlated with C-reactive protein level (p: .03, r: -.384). Serum selenium level was gradually decreased during the pregnancy period, however, this natural decrease was enhanced together with COVID-19 infection. The reason might be increased selenium needs depended on the immune response against infection. The decrease in maternal selenium level was found to be related to IL-6 and D-dimer levels, which indicate selenium's role in disease progression.

Clinical characteristics of hospitalised patients with COVID-19 and the impact on mortality: a single-network, retrospective cohort study from Pennsylvania state

Objective

COVID-19 is a respiratory disease caused by SARS-CoV-2 with the highest burden in the USA. Data on clinical characteristics of patients with COVID-19 in US population are limited. Thus, we aim to determine the clinical characteristics and risk factors for in-hospital mortality from COVID-19.

Design

Retrospective observational study.

Setting

Single-network hospitals in Pennsylvania state.

Participants

Patients with confirmed SARS-CoV-2 infection who were hospitalised from 1 March to 31 May 2020.

Primary and secondary outcome measures

Primary outcome was in-hospital mortality. Secondary outcomes were complications, such as acute kidney injury (AKI) and acute respiratory distress syndrome (ARDS).

Results

Of 283 patients, 19.4% were non-survivors. The mean age of all patients was 64.1±15.9 years. 56.2% were male and 50.2% were white. Several factors were identified from our adjusted multivariate analyses to be associated with in-hospital mortality: increasing age (per 1-year increment; OR 1.07 (1.045 to 1.105)), hypoxia (oxygen saturation <95%; OR 4.630 (1.934 to 1.111)), opacity/infiltrate on imaging (OR 3.077 (1.276 to 7.407)), leucocytosis (white blood cell >10 109/µL; OR 2.732 (1.412 to 5.263)), ferritin >336 ng/mL (OR 4.016 (1.195 to 13.514)), lactate dehydrogenase >200 U/L (OR 7.752 (1.639 to 37.037)), procalcitonin >0.25 ng/mL (OR 2.404 (1.011 to 5.714)), troponin I >0.03 ng/mL (OR 2.242 (1.080 to 4.673)), need for advanced oxygen support other than simple nasal cannula (OR 4.608-13.889 (2.053 to 31.250)), intensive care unit admission/transfer (OR 13.699 (6.135 to 30.303)), renal replacement therapy (OR 21.277 (5.025 to 90.909)), need for vasopressor (OR 22.222 (9.434 to 52.632)), ARDS (OR 23.810 (10.204 to 55.556)), respiratory acidosis (OR 7.042 (2.915 to 16.949)), and AKI (OR 3.571 (1.715 to 7.407)). When critically ill patients were analysed independently, increasing Sequential Organ Failure Assessment score (OR 1.544 (1.168 to 2.039)), AKI (OR 2.128 (1.111 to 6.667)) and ARDS (OR 6.410 (2.237 to 18.182)) were predictive of in-hospital mortality.

Conclusion

We reported the characteristics of ethnically diverse, hospitalised patients with COVID-19 from Pennsylvania state.

Micronutrients early in critical illness, selective or generous, enteral or intravenous?

PURPOSE OF REVIEW

Micronutrients have essential antioxidant and immune functions, while low blood concentrations are frequently observed in critically ill patients. This has led to the concepts of complementation, repletion, or even pharmacological supplementation. Over the last three decades, many clinical studies have tested the latter strategy, with controversial or negative results. Therefore, this review aims at evaluating micronutrient-related interventions that are mandatory or need to be assessed in future trials or clinical registries in all or specific critically ill patients.

RECENT FINDINGS

In the critically ill, low plasma/serum micronutrient levels not always reflect a true deficiency in the absence of demonstrable losses. Current practices of micronutrient provision and monitoring in critical care, vary substantially across the world. Also, recent clinical trials testing high dose as monotherapy (selenium, thiamine, vitamin C, vitamin D) or in combination have failed to demonstrate clinical benefits in sepsis. However, these studies have not applied a physiological integrative approach of micronutrient action.

SUMMARY

Micronutrients are essential in nutrition but their administration and monitoring are difficult. So far, different well designed RCTs on intravenous and oral high dose micronutrient supplementation have been conducted. Nevertheless, very high-dose single micronutrients cannot be advocated at this stage in sepsis, or any other critical condition. By contrast, studies using combination of moderate doses of micronutrients in specific diseases, such as burns and trauma have been associated with improved outcomes. Intravenous administration seems to be the most efficient route. Future clinical trials need to integrate the physiology underlying the interconnected micronutrient activity, and choose more specific primary and secondary endpoints.

Oxidative Stress Status in COVID-19 Patients Hospitalized in Intensive Care Unit for Severe Pneumonia. A Pilot Study

BACKGROUND

A key role of oxidative stress has been highlighted in the pathogenesis of COVID-19. However, little has been said about oxidative stress status (OSS) of COVID-19 patients hospitalized in intensive care unit (ICU).

MATERIAL AND METHODS

Biomarkers of the systemic OSS included antioxidants (9 assays), trace elements (3 assays), inflammation markers (4 assays) and oxidative damage to lipids (3 assays).

RESULTS

Blood samples were drawn after 9 (7-11) and 41 (39-43) days of ICU stay, respectively in 3 and 6 patients. Vitamin C, thiol proteins, reduced glutathione, γ-tocopherol, β-carotene and PAOT® score were significantly decreased compared to laboratory reference values. Selenium concentration was at the limit of the lower reference value. By contrast, the copper/zinc ratio (as a source of oxidative stress) was higher than reference values in 55% of patients while copper was significantly correlated with lipid peroxides (r = 0.95, p < 0.001). Inflammatory biomarkers (C-reactive protein and myeloperoxidase) were significantly increased when compared to normals.

CONCLUSIONS

The systemic OSS was strongly altered in critically ill COVID-19 patients as evidenced by increased lipid peroxidation but also by deficits in some antioxidants (vitamin C, glutathione, thiol proteins) and trace elements (selenium).

Preventing the development of severe COVID-19 by modifying immunothrombosis

BACKGROUND

COVID-19-associated acute respiratory distress syndrome (ARDS) is associated with significant morbidity and high levels of mortality. This paper describes the processes involved in the pathophysiology of COVID-19 from the initial infection and subsequent destruction of type II alveolar epithelial cells by SARS-CoV-2 and culminating in the development of ARDS.

MAIN BODY

The activation of alveolar cells and alveolar macrophages leads to the release of large quantities of proinflammatory cytokines and chemokines and their translocation into the pulmonary vasculature. The presence of these inflammatory mediators in the vascular compartment leads to the activation of vascular endothelial cells platelets and neutrophils and the subsequent formation of platelet neutrophil complexes. These complexes in concert with activated endothelial cells interact to create a state of immunothrombosis. The consequence of immunothrombosis include hypercoagulation, accelerating inflammation, fibrin deposition, migration of neutrophil extracellular traps (NETs) producing neutrophils into the alveolar apace, activation of the NLRP3 inflammazome, increased alveolar macrophage destruction and massive tissue damage by pyroptosis and necroptosis Therapeutic combinations aimed at ameliorating immunothrombosis and preventing the development of severe COVID-19 are discussed in detail.

Trace Element Levels in Serum Are Potentially Valuable Diagnostic Markers in Dogs

The objective of this study was to obtain information about the role of trace element imbalance in the pathogenesis of certain diseases in dogs and to evaluate the suitability of trace element profiling as an additional tool in the diagnosis. Serum trace element concentrations (copper, molybdenum, selenium and zinc) were measured in a cohort of healthy (control) dogs (n = 42) and dogs affected by hepatic (n = 25), gastrointestinal (n = 24), inflammatory/infection (n = 24), and renal (n = 22) diseases. These data were analyzed together with data on basic biochemical parameters (alanine aminotransferase, alkaline phosphatase, blood urea nitrogen, creatinine, albumin, globulin, and glucose) by using chemometric techniques. The chemometric analysis revealed distinctive association patterns between trace elements and biochemical parameters for each clinical disorders. The findings provide clear evidence for the important role of trace elements in disease, particularly in relation to acute phase reactions, with serum copper providing an indirect measurement of ceruloplasmin (positive acute-phase protein) and serum selenium and zinc acting as negative acute phase reactants. Molybdenum may also be a suitable marker of incipient renal disease. Thus, the analysis of trace element profiles, by multielement techniques, in a single serum sample would be a valuable additional tool for the diagnosis of certain diseases.

The pathophysiology of SARS-CoV-2: A suggested model and therapeutic approach

In this paper, a model is proposed of the pathophysiological processes of COVID-19 starting from the infection of human type II alveolar epithelial cells (pneumocytes) by SARS-CoV-2 and culminating in the development of ARDS. The innate immune response to infection of type II alveolar epithelial cells leads both to their death by apoptosis and pyroptosis and to alveolar macrophage activation. Activated macrophages secrete proinflammatory cytokines and chemokines and tend to polarise into the inflammatory M1 phenotype. These changes are associated with activation of vascular endothelial cells and thence the recruitment of highly toxic neutrophils and inflammatory activated platelets into the alveolar space. Activated vascular endothelial cells become a source of proinflammatory cytokines and reactive oxygen species (ROS) and contribute to the development of coagulopathy, systemic sepsis, a cytokine storm and ARDS. Pulmonary activated platelets are also an important source of proinflammatory cytokines and ROS, as well as exacerbating pulmonary neutrophil-mediated inflammatory responses and contributing to systemic sepsis by binding to neutrophils to form platelet-neutrophil complexes (PNCs). PNC formation increases neutrophil recruitment, activation priming and extraversion of these immune cells into inflamed pulmonary tissue, thereby contributing to ARDS. Sequestered PNCs cause the development of a procoagulant and proinflammatory environment. The contribution to ARDS of increased extracellular histone levels, circulating mitochondrial DNA, the chromatin protein HMGB1, decreased neutrophil apoptosis, impaired macrophage efferocytosis, the cytokine storm, the toll-like receptor radical cycle, pyroptosis, necroinflammation, lymphopenia and a high Th17 to regulatory T lymphocyte ratio are detailed.

Hypozincaemia is associated with severity of aneurysmal subarachnoid haemorrhage: a retrospective cohort study

BACKGROUND

Hypozincaemia may develop in critically ill patients, including those with acute brain injury in the early phase after hospital admission. The aim of this study was to investigate the prevalence of hypozincaemia after aneurysmal subarachnoid haemorrhage (aSAH) and its association with delayed cerebral ischemia and functional outcome.

METHODS

We retrospectively analysed a cohort of 384 patients with SAH admitted to the Neurointensive Care Unit at Rigshospitalet, Copenhagen, Denmark, in whom at least one measurement of plasma zinc concentration was done during the hospital stay. Hypozincaemia was defined as at least one measurement of plasma zinc below 10 μmol/L. Potential associations between hypozincaemia, demographic variables and functional outcome after aSAH were analysed in multivariable logistic regression models.

RESULTS

Hypozincaemia was observed in 67% (n = 257) of all patients and occurred within 7 days in more than 95% of all hypozincaemic patients. In a multivariable model, severe SAH (WFNS 3-5; OR 4.2, CI 2.21-8.32, p < 0.001) and Sequential Organ Failure Assessment (SOFA) score on the day of admission (OR 1.24, CI 1.11-1.40, p < 0.001) were independently associated with hypozincaemia. In another multivariable model, hypozincaemia was independently associated with an unfavourable outcome (defined as a modified Rankin Scale score from 3 to 6) (OR 1.97, CI 1.06-3.68, p = 0.032), as was age (OR 1.03, CI 1.01-1.05, p = 0.015), SOFA score on the day of admission (OR 1.14, CI 1.02-1.29, p = 0.02), a diagnosis of delayed cerebral ischaemia (OR 4.06, CI 2.29-7.31, p < 0.001) and a clinical state precluding assessment for delayed cerebral ischaemia (OR 15.13, CI 6.59-38.03, p < 0.001).

CONCLUSION

Hypozincaemia occurs frequently after aSAH, is associated with a higher disease severity and independently contributes to an unfavourable outcome.

Association of Initial Low Serum Selenium Level with Infectious Complications and 30-Day Mortality in Multiple Trauma Patients

Low serum selenium levels are commonly observed in critically injured multiple trauma patients. This study aimed to identify the association between initial serum selenium levels and in-hospital infectious complications in multiple trauma patients. We retrospectively reviewed multiple trauma patients admitted between January 2015 and November 2017. We selected 135 patients whose serum selenium levels were checked within 48 h of admission. Selenium deficiency was defined as a serum selenium level <70 ng/mL. Survival analyses of selenium deficiency and 30-day mortality were performed. Multivariate logistic regression analysis was performed to identify the association between initial serum selenium level and in-hospital infectious complications. Thirty-day mortality (8.3% vs. 0.0%; p = 0.018) and incidence rates of pneumonia (66.7% vs. 28.3%; p < 0.001) and infectious complications (83.3% vs. 46.5%; p < 0.001) were higher in patients with selenium deficiency than in patients without selenium deficiency. Kaplan–Meier survival cures also showed similar results (log rank test, p = 0.021). Of 135 patients, 76 (56.3%) experienced at least one infectious complication during admission. High injury severity score (ISS, odds ratio (OR) 1.065, 95% confidence interval (CI) 1.024–1.108; p = 0.002) and selenium deficiency (OR 3.995, 95% CI 1.430–11.156; p = 0.008) increased the risk of in-hospital infectious complications in multiple trauma patients. Patients with selenium deficiency showed higher 30-day mortality and higher risks of pneumonia and infectious complications.

The acute phase serum zinc concentration is a reliable biomarker for predicting the functional outcome after spinal cord injury

BACKGROUND

Spinal cord injury (SCI) is a devastating disorder for which the accurate prediction of the functional prognosis is urgently needed. Due to the lack of reliable prediction methods, the acute evaluation of SCI severity and therapeutic intervention efficacy is extremely difficult, presenting major obstacles to the development of acute SCI treatment. We herein report a novel method for accurately predicting the functional prognosis using the acute-phase serum zinc concentration after SCI.

METHODS

We produced experimental animal SCI models with different prognoses and examined the relationship among the SCI severity, functional outcome, and acute-phase serum zinc concentration. We also examined whether we could predict the functional prognosis by evaluating the serum zinc concentration within 72 h after SCI in a human prospective study.

FINDINGS

In a mouse model, the acute serum zinc concentrations decreased in proportion to SCI severity and the serum zinc concentrations at 12 h after SCI accurately predicted the functional prognosis. We clarified the mechanism underlying this serum zinc proportional decrease, showing that activated monocytes took up zinc from blood-serum and then infiltrated the lesion area in a severity-dependent manner. A non-linear regression analysis of 38 SCI patients showed that the serum zinc concentrations in the acute-phase accurately predicted the long-term functional outcome (R2 = 0·84) more accurately than any other previously reported acute-phase biomarkers.

INTERPRETATION

The acute-phase serum zinc concentration could be a useful biomarker for predicting the functional prognosis. This simple method will allow for more objective clinical trials and the development of patient-tailored treatment for SCI.

Inflammatory process of patients receiving parenteral nutrition is not exclusively responsible for low selenium and glutathione peroxidase levels

OBJECTIVE

The aim of this study was to verify if the selenium status of patients residing in locations with selenium-poor soil who receive parenteral nutrition (PN) without selenium supplementation is associated with the inflammatory process.

METHODS

This was a prospective cohort study with hospitalized patients who started PN. The analyzed biochemical tests were plasma selenium, glutathione peroxidase (GPx), C-reactive protein, prealbumin, albumin, creatinine, lymphocytes, total cholesterol, high-density lipoprotein, and triglycerides.

RESULTS

Seventy-seven patients with a mean age of 56.2 ± 15.7 y were studied. Most of them used PN as a result of clinical issues (70.1%) such as, gastric, renal, or hematologic neoplasia; gastrointestinal dysfunction; pancreatitis; sepsis; trauma without surgical needs; chylothorax; and fistula not related to surgical procedure. There were low levels of plasma selenium (98.7%) and GPx (60%) and elevated C-reactive protein (98.5%) in most cases. At the beginning of PN there was no correlation between selenium and laboratory tests (P > 0.05). At the second evaluation (seventh day of PN), there was a positive correlation of selenium levels with lymphocyte levels (r = 0.36; P = 0.04). After 2 wk of PN, there was a statistically significant correlation between selenium and GPx (r = 0.70; P = 0.02).

CONCLUSIONS

Very low values of selenium and GPx from the beginning of PN were identified. The correlation of selenium levels with GPx in only 14 d of PN, regardless of inflammation, may reflect a critical selenium status, mainly because the correlation was verified after the acute phase. Therefore it is important to emphasize that supplementation should be started from the beginning of PN, especially in regions with selenium-deficient soil.

Relationship between nutritional status and the systemic inflammatory response: micronutrients

Micronutrients such as trace elements and vitamins are important as enzyme cofactors in the metabolism of all cells in the body and therefore key to determining nutritional status. The present systematic review examined the evidence of the impact of the systemic inflammatory response on plasma micronutrient status in acute (surgical) and chronic tissue injury. A literature review using targeted subject headings was carried out. Plasma C-reactive protein was used to classify minor (<10 mg/l), moderate (11–80 mg/l) and major (>80 mg/l) inflammation. The literature search produced 2344 publications and plasma vitamin D, zinc and carotenoids were most commonly studied and plasma vitamins K, B2and B6were least studied. In acute injury thirteen studies (all prospective) and in chronic injury twenty-four studies (largely retrospective) were included in the review. There was consistent evidence that most common measured micronutrients in the plasma (zinc, selenium, vitamins A, D, E, K, B2, B6, B12, C, lutein, lycopene, α- and β-carotene) were significantly lowered from minor to moderate to major inflammation. The results of the present systematic review indicate that most plasma micronutrients fall as part of the systemic inflammatory response irrespective of acute or chronic injury. Therefore, in the presence of a systemic inflammation, plasma micronutrient concentrations should be interpreted with caution. There are a number of methods applied to adjust plasma micronutrient concentrations to avoid misdiagnosis of deficiency. Alternatively, intracellular measurements appear to obviate the need for such plasma adjustment to assess micronutrient status.