[Guidelines for the diagnosis and treatment of severe traumatic brain injury. Part 2. Intensive care and neuromonitoring]

Traumatic brain injury (TBI) is one of the major causes of death and disability in young and middle-aged people. The most problematic group is comprised of patients with severe TBI who are in a coma. The adequate diagnosis of primary brain injuries and timely prevention and treatment of the secondary injury mechanisms largely define the possibility of reducing mortality and severe disabling consequences. When developing these guidelines, we used our experience in the development of international and national recommendations for the diagnosis and treatment of mild traumatic brain injury, penetrating gunshot wounds to the skull and brain, severe traumatic brain injury, and severe consequences of brain injuries, including a vegetative state. In addition, we used international and national guidelines for the diagnosis, intensive care, and surgical treatment of severe traumatic brain injury, which had been published in recent years. The proposed guidelines concern intensive care of severe TBI in adults and are particularly intended for neurosurgeons, neurologists, neuroradiologists, anesthesiologists, and intensivists who are routinely involved in the treatment of these patients.

Tracheostomy management in patients with severe acute respiratory distress syndrome receiving extracorporeal membrane oxygenation: an International Multicenter Retrospective Study

Background

Current practices regarding tracheostomy in patients treated with extracorporeal membrane oxygenation (ECMO) for acute respiratory distress syndrome are unknown. Our objectives were to assess the prevalence and the association between the timing of tracheostomy (during or after ECMO weaning) and related complications, sedative, and analgesic use.

Methods

International, multicenter, retrospective study in four large volume ECMO centers during a 9-year period.

Results

Of the 1,168 patients treated with ECMO for severe ARDS (age 48 ± 16 years, 76% male, SAPS II score 51 ± 18) during the enrollment period, 353 (30%) and 177 (15%) underwent tracheostomy placement during or after ECMO, respectively. Severe complications were uncommon in both groups. Local bleeding within 24 h of tracheostomy was four times more frequent during ECMO (25 vs 7% after ECMO, p < 0.01). Cumulative sedative consumption decreased more rapidly after the procedure with sedative doses almost negligible 48–72 h later, when tracheostomy was performed after ECMO decannulation (p < 0.01). A significantly increased level of consciousness was observed within 72 h after tracheostomy in the “after ECMO” group, whereas it was unchanged in the “during-ECMO” group.

Conclusion

In contrast to patients undergoing tracheostomy after ECMO decannulation, tracheostomy during ECMO was neither associated with a decrease in sedation and analgesia levels nor with an increase in the level of consciousness. This finding together with a higher risk of local bleeding in the days following the procedure reinforces the need for a case-by-case discussion on the balance between risks and benefits of tracheotomy when performed during ECMO.

Supplementary Information

The online version contains supplementary material available at 10.1186/s13054-021-03649-8.

Impact of pathogen reduction methods on immunological properties of the COVID-19 convalescent plasma

BACKGROUND AND OBJECTIVES

COVID-19 convalescent plasma is an experimental treatment against SARS-CoV-2. The aim of this study is to assess the impact of different pathogen reduction methods on the levels and virus neutralizing activity of the specific antibodies against SARS-CoV2 in convalescent plasma.

MATERIALS AND METHODS

A total of 140 plasma doses collected by plasmapheresis from COVID-19 convalescent donors were subjected to pathogen reduction by three methods: methylene blue (M)/visible light, riboflavin (R)/UVB and amotosalen (A)/UVA. To conduct a paired comparison, individual plasma doses were divided into 2 samples that were subjected to one of these methods. The titres of SARS-CoV2 neutralizing antibodies (NtAbs) and levels of specific immunoglobulins to RBD, S- and N-proteins of SARS-CoV-2 were measured before and after pathogen reduction.

RESULTS

The methods reduced NtAbs titres differently: among units with the initial titre 80 or above, 81% of units remained unchanged and 19% decreased by one step after methylene blue; 60% were unchanged and 40% decreased by one step after amotosalen; after riboflavin 43% were unchanged and 50% (7%, respectively) had a one-step (two-step, respectively) decrease. Paired two-sample comparisons (M vs. A, M vs. R and A vs. R) revealed that the largest statistically significant decrease in quantity and activity of the specific antibodies resulted from the riboflavin treatment.

CONCLUSION

Pathogen reduction with methylene blue or with amotosalen provides the greater likelihood of preserving the immunological properties of the COVID-19 convalescent plasma compared to riboflavin.

[Guidelines for the management of severe traumatic brain injury. Part 3. Surgical management of severe traumatic brain injury (Options)]

Traumatic brain injury (TBI) is one of the main causes of mortality and severe disability in young and middle age patients. Patients with severe TBI, who are in coma, are of particular concern. Adequate diagnosis of primary brain injuries and timely prevention and treatment of secondary injury mechanisms markedly affect the possibility of reducing mortality and severe disability. The present guidelines are based on the authors' experience in developing international and national recommendations for the diagnosis and treatment of mild TBI, penetrating gunshot wounds of the skull and brain, severe TBI, and severe consequences of brain injury, including a vegetative state. In addition, we used the materials of international and national guidelines for the diagnosis, intensive care, and surgical treatment of severe TBI, which were published in recent years. The proposed recommendations for surgical treatment of severe TBI in adults are addressed primarily to neurosurgeons, neurologists, neuroradiologists, anesthesiologists, and intensivists who are routinely involved in treating these patients.

Clinical and pathophysiologic aspects of ECMO-associated hemorrhagic complications

Extracorporeal membrane oxygenation (ECMO) is increasingly used to treat severe cases of acute respiratory or cardiac failure. Hemorrhagic complications represent one of the most common complications during ECMO, and can be life threatening. The purpose of this study was to elucidate pathophysiological mechanisms of ECMO-associated hemorrhagic complications and their impact on standard and viscoelastic coagulation tests. The study cohort included 27 patients treated with VV-ECMO or VA-ECMO. Hemostasis was evaluated using standard coagulation tests and viscoelastic parameters investigated with rotational thromboelastometry. Anticoagulation and hemorrhagic complications were analyzed for up to seven days depending on ECMO duration. Hemorrhagic complications developed in 16 (59%) patients. There were 102 discrete hemorrhagic episodes among 116 24-hour-intervals, of which 27% were considered to be clinically significant. The highest number of ECMO-associated hemorrhages occurred on the 2^nd and 3^rd day of treatment. Respiratory tract bleeding was the most common hemorrhagic complication, occurring in 62% of the 24-hour intervals. All 24-hours-intervals were divided into two groups: “with bleeding” and “without bleeding”. The probability of hemorrhage was significantly associated with abnormalities of four parameters: increased international normalized ratio (INR, sensitivity 71%, specificity 94%), increased prothrombin time (PT, sensitivity 90%, specificity 72%), decreased intrinsic pathway maximal clot firmness (MCFin, sensitivity 76%, specificity 89%), and increased extrinsic pathway clot formation time (CFTex, sensitivity 77%, specificity 87%). In conclusions, early ECMO-associated hemorrhagic complications are related to one traditional and two novel viscoelastic coagulation abnormalities: PT/INR elevation, reduced maximum clot firmness due to intrinsic pathway dysfunction (MCFin), and prolonged clot formation time due to extrinsic pathway dysfunction (CFTex). When managing hemostasis during ECMO, derangements in PT/INR, MCFin and CFT_ex should be focused on.

Guidelines for the management of severe head injury. Part 1. Neurotrauma system and neuroimaging

Traumatic brain injury is one of the main causes of mortality and disability in young and middle-aged individuals. The patients with severe traumatic brain injury who are in coma are the most difficult to deal with. Appropriate diagnosis of the primary brain injuries and early prevention and treatment of secondary damage mechanisms largely determine the possibility of reducing mortality and severe disabling consequences. The authors compiled these guidelines based on their experience in development of international and Russian recommendations on the diagnosis and treatment of mild traumatic brain injury, penetrating gunshot injury of the skull and brain, severe traumatic brain injury, and severe consequences of brain injuries, including a vegetative state. In addition, we used the materials of international and Russian recommendations on the diagnosis, intensive care, and surgical treatment of severe traumatic brain injury published in recent years. The proposed recommendations are related to organization of medical care and diagnosis of severe traumatic brain injury in adults and are primarily addressed to neurosurgeons, neurologists, neuroradiologists, anesthesiologists, and emergency room doctors, who are routinely involved in management of these patients.

[New perspectives of motor rehabilitation of patients after focal brain lesions]

Rehabilitation of patients after focal brain lesions is one of the topical issues of modern medicine. Motor disorders are known to develop in more than 80% of survivors of stroke and traumatic brain injury and be one of the main causes of disability, which necessitates an active search for new effective techniques for correction of motor disorders. Modern rehabilitation includes both traditional techniques for recovery of patients with motor deficit (exercise therapy and physiotherapy) and botulinum therapy, kinesiotherapy, mechanotherapy, etc., which have been developed in recent years. Robotic technologies have been developed, improved, and implemented. Currently, due to progress in computerization, virtual reality-based rehabilitation of patients is of particular interest. The article reviews the key studies in this field. We describe various visualization methods and means of immersion in a virtual environment for recovery of upper and lower extremity function in patients with focal brain lesions. The study provides an assessment of the effectiveness and safety of various virtual reality-based rehabilitation programs in patients with motor disorders after stroke and traumatic brain injury.

Diagnosis and treatment of persons with acute thallium poisoning

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This study presents a case of mass thallium poisoning including 44 persons.

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For thallium poisoning, early diagnose is difficult and treatment approaches should be developed.

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Delayed alopecia and skin lesions are specific features of thallium poisoning.

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A combination of potassium-ferric hexacyanoferrate and intestinal lavage is effective against this poisoning.

Objective

This study aimed to describe organs and systems damages in persons after mass poisoning with thallium and show the results of treatment.

Methods

Forty-four persons (12 males and 32 females) with acute oral thallium poisoning were tested for thallium levels in blood and urine and examined by a toxicologist and a neurologist, and in some –cases, by a gynecologist, an ophthalmologist, and a psychiatrist. Persons were divided into the following three groups depending on the severity of the poisoning: I: This group consisted of 9 persons (blood thallium level 8.3–26.7 μg/L) and treatment applied in the hospital included intestinal lavage, antidote therapy with potassium-ferric hexacyanoferrate, sodium dimercaptopropanesulfonate; II: This group consisted of 21 persons (0.3-6.1 μg/L) who received a similar treatment at home; and III: This group consisted of 14 (normal) persons who did not receive any treatment.

Results

The most common combination of several symptoms such as alopecia (on day 17–23), muscle pain of different localization in the debut of the disease (>88.9 % of the persons), sudden unexplained general weakness (>76.2 % of the persons), peripheral paraparesis or tetraparesis (including no complaints), polyneuropathy (88.89 % in group I vs. 54.14 % in group II, p < 0.05), static and dynamic ataxia (33.3 % in group I vs. 19.4 % in group II, p < 0.05), vertigo (1/3 of the persons), postural tremor (1/3 of the persons), and cognitive and emotional disorders (2/3 of the persons). Ovarian dysfunction was observed in all women of group I but in 42.9 % of group II, p < 0.05. The treatment was successful. In group I, plasma and urine thallium level significantly decreased by 69.3 % and 84 %, respectively. Pain, movement and coordination disorders regressed first while tremor, sensory, cognitive and emotional disorders lasted longer. Polyneuropathies later became mononeuropathies. Tremor could increase despite a decreased thallium concentration.

Discussion

The Sklifosovsky Institute conducted the largest study in Russian Federation investigating disorders in persons with acute thallium poisoning confirmed by laboratory tests. The clinical symptoms were consistent with those reported in the literature. The applied treatment was successful and led to better results compared to our previous approaches of treating mass thallium poisoning.

Conclusions

This study shows a typical combination of thallium poisoning symptoms and allows us to recommend a complex therapy without the use of extracorporeal detoxification methods.

Thermovaccination - thermoheliox as a stimulator of the immune response. Kinetics of the synthesis of antibodies and C-reactive protein in coronavirus infection

Clinical trials of thermoheliox application (inhalation with a high-temperature mixture of oxygen and helium, 90 °C) in the treatment of the acute phase of coronavirus infection were conducted. Dynamics of disease development in infected patients (PCR test for the virus) and, dynamics of changes in blood concentration of C-reactive protein, immunoglobulin M, specific immunoglobulin G were studied. High efficiency of thermoheliox in releasing the organism from the virus and stimulating the immune response (thermovaccination effect) was shown. The kinetic model of the process is proposed and analyzed.

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Clinical trials of thermoheliox application in the treatment of acute phase of coronavirus were performed.

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High efficiency of thermoheliox in stimulating the immune response (thermovaccination effect) was shown.

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Influence of thermoheliox on IgG synthesis kinetics and kinetic behavior of C-reactive protein is studied.

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Kinetic model for the synthesis of antibodies and CRP is proposed.

Long-term follow-up study of post-COVID-19 patients

Aim. To evaluate dynamic changes in the lungs, hemostasis system, immune system in different terms after coronavirus pneumonia. Materials and methods. Ventilation-perfusion single-photon emission computed tomography/computed tomography (CT), functional methods of lung investigation, evaluation of hemostasis system, immune status and specific humoral immune response were performed and evaluated in different terms after coronavirus pneumonia. A total of 71 patients were examined according to this protocol. We examined patients with the lesion volume not less than 50% according to chest CT. All patients were divided into 2 groups depending on the distance from the acute stage of coronavirus pneumonia. Group 1 included patients who were examined early (3060 days after hospital discharge), group 2 included patients who were examined later (61180 days after hospital discharge). Results. We obtained gradual regression of pathologically-modified tissue from 67.3% during the inpatient phase to 30.9% during the early period and to 19.7% during the late period of examination, according to CT scan of the chest organs. The same tendency was demonstrated by diffusion capacity of the lungs. Perfusion scintigraphy data showed a decrease in perfusion deficit from 26.012.8% during the early period of examination to 19.46.2% during the late period of examination. On the contrary, ventilatory scintigraphy demonstrates the increase of isotope passage time through the alveolar-capillary membrane over time (from 48.231.3 minutes in the early period to 83.637.2 minutes in the late period). An increase in D-dimer was detected in 24% of patients in the early group. The levels of inflammatory markers, indices of immune status, and specific humoral immune response did not differ in the two described groups. Conclusion. The results demonstrate gradual regression of pathological changes caused by coronavirus infection.

[Dilated cardiomyopathy as a cause of ischemic stroke]

Dilated cardiomyopathy (DCMP) is a disease of the myocardium characterized by the dilatation of heart cavities with the development of systolic dysfunction but without a decrease in the thickness of the myocardium. DCMP is a frequent cause of cardioembolic syndrome, in particular cardioembolic ischemic stroke (CES). A case of a patient with DCMP after CES is presented.

Optically transparent electrodes to study living cells: A mini review

The use of electrochemical methods to study living systems, including cells, has been of interest to researchers for a long time. Thus, controlling the polarization of the electrode contacting living cells, one can influence, for example, their proliferation or the synthesis of specific proteins. Moreover, the electrochemical approach formed the basis of the biocompatibility improvement of the materials contacting with body tissues that use in carbon hemosorbents and implants development. It became possible to reach a fundamentally new level in the study of cell activity with the introduction of optically transparent electrodes in this area. The advantage of the using of optically transparent electrodes is the possibility of simultaneous analysis of living cells by electrochemical and microscopic methods. The use of such materials allowed approaching to the study of the influence of the electrode potential on adhesion activity and morphology of the different cell types (HeLa cells, endothelial cell, etc.) more detailed. There are a negligible number of publications in this area despite the advantages of the usage of optically transparent electrodes to study living cells. This mini-review is devoted to some aspects of the interaction of living cells with conductive materials and current advances in the use of optically transparent electrodes for the study of living cells, as well as the prospects for their use in cellular technologies.

[Locoregional anesthesia in endoscopic surgery of intracerebral hypertensive hemangiomas]

Introduction

Currently, minimally invasive methods of surgical treatment of hypertensive intracerebral hematomas (ICHs) are actively used. However, anesthetic management of these surgeries are unclear. Moreover, advisability of locoregional anesthesia (LRA) for endoscopic aspiration of hypertensive ICHs has not been studied.

Objective

To analyze application of regional anesthesia in minimally invasive surgery of hypertensive intracerebral hematomas.

Material and methods

Patients were divided into 2 groups. Group 1 included 45 patients who underwent surgery under total intravenous anesthesia with mechanical ventilation (TIVA + mechanical ventilation), group 2 (n=43) - surgery under LRA. The incidence of pneumonia and postoperative outcomes in accordance with the GOS grading system were analyzed depending on the method of anesthesia.

Results

Pneumonia was 3 times more common in the first group (33%) that required prolonged ventilation and tracheostomy. Thus, there were 9 tracheostomies (20%) in the first group. In the second group, one patient required mechanical ventilation on the second postoperative day due to severe chronic obstructive pulmonary disease followed by deterioration of respiratory failure. Tracheostomy was also performed in this case. According to analysis of GOS outcomes, the LRA group was characterized by 4 times lower mortality and 1.5 times greater number of patients with good recovery and moderate disabilities compared with the first group.

Conclusions

LRA is a feasible and effective method for the anesthetic management of minimally invasive surgery in patients with hypertensive ICHs. This approach ensures decrease of mortality rate, increase of good neurological outcomes and reduce pulmonary infectious complications.

[Current guidelines for the diagnosis and treatment of severe brain injury]

Based on the international and Russian guidelines, the paper describes standards, recommendations and options developed on the principles of evidence-based medicine for severe brain injury. It also presents a spectrum of recognition, management, and differential treatment of victims with severe brain and skull injury.

[Prognostic significance of leukocyte count in the venous blood in the acute stage of cerebral aneurism rupture]

AIM

To determine a prognostic role of leukocyte count in the venous blood in the acute stage of cerebral aneurysm (CA) rupture.

MATERIAL AND METHODS

Fifty-one patients with CA rupture, aged from 20 to 65 years, hospitalized in the first 72 h over the period from 01.10.12 to 01.02.16 were examined. The severity of disease and anatomical form of hemorrhage was corresponded to III-IV degree on the W. Hunt - R. Hess scale and Fisher scale. All patients underwent surgery. Outcomes after open and endovascular surgeries were similar.

RESULTS

Normal leukocyte number in the venous blood at admission was identified in 12 (24%) of patients (on average 7.3±1.4·109/L), leukocytosis in 39 (76%) (14.3±3.1·109/L) (p<0.0001). Leukocyte number in the acute stage of CA rupture was correlated with the frequency and severity of the vessel spasm. In 28 (55%) of patients with ischemic lesions of the brain matter, mean leukocyte number in the first 72 h after hemorrhage was higher by 2-24% (3±4.8·109/L) compared to patients without ischemia (11.9±2.5·109/L) (p=0.06). The level of leukocytes in survivors was lower by 3 - 28% (122±3.4·109/L) compared to patients with fatal outcome and patients with severe neurological deficit after the surgery (14.5±3.9·109/L) (p>0.05).

CONCLUSION

The increase in leukocyte number in the venous blood in the first 72 h after CA rupture ≥10,1·109/L is a reliable risk factor of marked vessel spasm. The level of leukocytes in patients with cerebral ischemia and poor prognosis in the first 72h after aneurysmal hemorrhage was higher by 2-28% compared to survivors without neurological impairment or mild neurological deficit.

[Sepsis in patients with intracranial hemorrhage: incidence and influence on outcome]

The aim of the study is to analyze sepsis and septic shock incidence and their influence on the outcome in critically ill patients with intracranial hemorrhage. Sepsis incidence (33,7%) and septic shock incidence (18,6%) in the patients studied did not depend on intracranial hemorrhage etiology. Septic complications led to higher mortality which was 22,8% in patients with sepsis and 74,4% in patients with septic shock. Sepsis and septic shock risk factors are defined. The problem of sepsis and septic shock diagnosis in critically ill patients with intracranial hemorrhage are highlighted.

[Effect of hemotransfusion on brain oxygenation and metabolism in patients with intracranial hemorrhages]

The paper analyzes the impact of anemia correction on the time course of changes in oxygen tension in the brain and on the biochemical composition of brain interstitial fluid (tissue microdialysis) in the affected and conditionally intact hemisphere in 8 patients with intracranial hemorrhages and a reduced awakening level up to 4-8 scores by the Glasgow coma scale. Anemia correction in patients with intracranial hemorrhage was shown to fail to change oxygen tension in the brain and to be followed by a reduction in lactate/pyruvate ratio in the involved cerebral hemisphere. Only in significant anemia (Hb < 7 g/dl), hemotransfusion elevated cerebral perfusion pressure, by increasing mean blood pressure.

[Decompressive craniotomy in the complex intensive treatment of malignant forms of massive ischemic stroke]

A group of patients with benign course of massive ischemic stroke (MII) without development of the dislocation syndrome and a group of patients with malignant course with development of the hemispheric brain edema with the following transtentorial herniation were singled out. Risk factors for the development of malignant form of MII and its fatal outcomes were specified as lateral dislocation (>7 mm), more than 70% of ischemia size in frontal and parietal lobes and more than 80% - in temporal lobes, the disturbance of wakefulness up to moderate coma or more. Based on these results, it was selected patients for decompressive craniotomy in the affected hemisphere that allowed to reduce the fatality rate by more than twice compared to patients treated without surgery.

[Systemic hemodynamic disorders in critically ill patients with intracranial hemorrhages]

The paper analyzes systemic hemodynamic disorders in 45 victims of severe brain injury and patients with nontraumatic intracranial hemorrhages. The incidence of hypovolemia in patients with nontraumatic intracranial hemorrhages and victims of severe brain injury is 65.4% and 73.7%, respectively. Infusion therapy based on the estimation of routine hemodynamic parameters (blood pressure, heart rate, central venous pressure, daily fluid balance) could not prevent hypovolemia in the examinees and caused a high rate of sympathomimetic use in uncorrected volemic states.

[Enteral therapy in patients with blunt abdominal trauma]

OBJECTIVE

To improve the outcomes in ICU patients with blunt abdominal trauma via enteral therapy by saline enteral solution.

MATERIAL AND METHODS

A retrospective and prospective study included 24 patients (18 (75%) men and 6 (25%) women) with blunt abdominal trauma who underwent examination and treatment at the Sklifosovsky Research Institute for Emergency Care. Age of patients ranged from 38 to 81 years (mean 50.1±13.6).

RESULTS

Enteral therapy was followed by normalization of serum lactate, alanine aminotransferase and aspartate aminotransferase after 3 days. There were significant differences in decrease of lactate dehydrogenase, alanine aminotransferase and C-reactive protein. In the control group, these parameters decreased only by the 10th day.

CONCLUSION

Inclusion of saline enteral solution into the complex therapy contributes to earlier recovery of gastrointestinal function and prevents compartment syndrome. These aspects reduced the number of patients with multiple organ failure.

[Endoscopic ultrasonography in diagnosis of chemical esophageal burn and prediction of cicatricial stenosis]

OBJECTIVE

To analyze the role of endoscopic ultrasonography (EUS) in predicting the risk of cicatricial stenosis after chemical esophageal burn.

MATERIAL AND METHODS

A retrospective study included 56 patients with chemical esophageal burn grade III/IV. Primary endoscopy was performed upon admission. To estimate lesion of muscular layer of esophageal wall, we performed EUS using mini-sensor 20 MHz in 3-5 days after injury. To assess severity of chemical esophageal burn, we used the classification proposed by Volkov S.V. (1997) and supplemented by Pesnya-Prasolova E.A. (2006): grade I - catarrhal damage, grade II - erosive, grade III - ulcerative, grade IV - ulcerative-necrotic damage.

RESULTS

To predict the risk of cicatricial esophageal stenosis, we identified 4 grades (a, b, c, d) of damage to muscular layer of esophageal wall considering EUS data. There was no esophageal stenosis in chemical esophageal burn grade III/IVa and acetic essence poisoning with esophageal burn grade IVb. Cicatricial stenosis occurred in 22 (78.6%) out of 28 patients with chemical esophageal burn grade IV (chemical burn grade IVb following alkalis poisoning and in all patients with chemical burn grade IVc/IVd). The risk of cicatricial stenosis was 9.4 times higher after alkalis burn compared to acetic acid burn.

CONCLUSION

EUS in chemical esophageal burn grade IV made it possible to identify additional grades (a, b, c, d) of damage to muscular layer of esophageal wall. This increased the effectiveness of endoscopic diagnostics and assessment of the risk of cicatricial esophageal stenosis.

GWAS and polygenic risk score of severe COVID-19 in Eastern Europe

Background

COVID-19 disease has infected more than 772 million people, leading to 7 million deaths. Although the severe course of COVID-19 can be prevented using appropriate treatments, effective interventions require a thorough research of the genetic factors involved in its pathogenesis.

Methods

We conducted a genome-wide association study (GWAS) on 7,124 individuals (comprising 6,400 controls who had mild to moderate COVID-19 and 724 cases with severe COVID-19). The inclusion criteria were acute respiratory distress syndrome (ARDS), acute respiratory failure (ARF) requiring respiratory support, or CT scans indicative of severe COVID-19 infection without any competing diseases. We also developed a polygenic risk score (PRS) model to identify individuals at high risk.

Results

We identified two genome-wide significant loci (P-value <5 × 10-8) and one locus with approximately genome-wide significance (P-value = 5.92 × 10-8-6.15 × 10-8). The most genome-wide significant variants were located in the leucine zipper transcription factor like 1 (LZTFL1) gene, which has been highlighted in several previous GWAS studies. Our PRS model results indicated that individuals in the top 10% group of the PRS had twice the risk of severe course of the disease compared to those at median risk [odds ratio = 2.18 (1.66, 2.86), P-value = 8.9 × 10-9].

Conclusion

We conducted one of the largest studies to date on the genetics of severe COVID-19 in an Eastern European cohort. Our results are consistent with previous research and will guide further epidemiologic studies on host genetics, as well as for the development of targeted treatments.