UPDATED RECOMMENDATIONS FOR THE PREVENTION, DIAGNOSIS AND TREATMENT OF COVID-19 IN CHILDREN IN POLAND. RECOMMENDATIONS FOR PEDIATRICIANS AND GENERAL PRACTITIONERS (18.02.2022).

The course of COVID-19 in pediatric patients is usually mild or asymptomatic, but with the dominance of new virus variants, more children become symptomatic and require hospitalization. Since the end of 2021, a significant increase in the percentage of children infected with SARS-CoV-2 has been observed. This paper aimed to update the recommendations on the management of a child with COVID-19 in outpatient and inpatient settings. The current possibilities of prophylaxis, diagnostics, and antiviral treatment were discussed, indicating the limited availability of therapy for children. The mainstay of COVID-19 treatment in most pediatric patients is symptomatic and supportive treatment, as well as measures aimed at reducing the spread of SARS-CoV-2 infection.Copyright © 2022, Wydawnictwo Czelej Sp. z o.o.. All rights reserved.

GUIDELINES FOR IMMUNIZATION OF CHILDREN FOLLOWING MULTISYSTEM INFLAMMATORY SYNDROME IN CHILDREN (MIS-C).

Multisystem inflammatory syndrome in children, MIS-C is also referred to as a paediatric inflammatory multisystem syndrome, PIMS. It is a late complication of SARS-CoV-2 infec-tion. The underlying cause is immunological dysregulation, leading to severe inflammatory processes. Children with PIMS require hospital treatment, the use of immunomodulating drugs, and often intensive care. The high effectiveness of COVID-19 vaccination has been demonstrated in the prevention of MIS-C in adolescents. However, there are no explic-it vaccination recommendations for children who have already suffered from MIS-C. We present a summary of current knowledge on vaccinations against COVID-19 in the context of MIS-C and the Polish guidance of vaccinations for children following MIS-C.Copyright © 2022, Wydawnictwo Czelej Sp. z o.o.. All rights reserved.

Lack of Evidence for Kidney Invasion by SARS-CoV-2 in a Lethal Mouse Model

Background: There is an ongoing controversy as to whether SARS CoV-2 can infect the kidney parenchyma directly. To date, the presence of SARS CoV-2 in the kidney has been described mainly post-mortem in autopsy studies of patients who died of or with COVID-19, but this has not been examined in an experimental model where the timing of SARS-CoV-2 infection can be defined. We used transgenic mice expressing human ACE2 (k18hACE2) susceptible to lethal SARS-CoV-2 infection to study this issue directly on kidney tissue taken at defined time points and using lung tissue as positive control. Method(s): Transgenic k18hACE2 mice were inoculated with 3x104 PFU SARSCoV-2 in a BSL-3 facility. Kidneys and lungs were removed from the animals sacrificed on days 5 to 7 and used for histology (PAS-staining), immunofluorescence (IF) of the S1 spike protein of SARS-CoV-2 and measurement of viral load by plaque assay. Kidney samples were additionally evaluated by IF using kidney injury markers NGAL and KIM-1. Result(s): Kidney tissue stained using an anti-S1-spike antibody showed negative results in all samples (n=15). By plaque assay, viral titers were also not detectable in any of the kidneys. By contrast, lungs from infected mice showed strong staining for the S1 spike protein in 13 of 14 cases and this was associated with positive viral titers in all lung samples. Despite severe lung disease, only mild and variable kidney damage was observed by histopathology. Positive staining for NGAL in the proximal tubules was consistently seen, while KIM-1 staining was rarely positive. Conclusion(s): In a transgenic mouse model with lethal SARS-CoV-2 infection and severe lung but mild kidney disease there is no evidence of S1 spike protein in the kidney, which is consistent with lack of detection of replicating virus by plaque assay.

Neutralization of the Omicron Variant of SARS-CoV-2 Is Effective by a Human and a Mouse Soluble ACE2 Protein

Background: We have previously reported that ACE2 618-DDC-ABD, a soluble ACE2 protein with extended duration of action and increased binding affinity for SARSCoV-2, provides lung and kidney protection in a lethal mouse model of SARS-CoV-2 infection. Moreover, we showed that this protein also neutralizes the gamma and delta variant SARS-CoV-2 infection in Vero E6 cells. As omicron is most prevalent SARSCoV-2 variant we tested whether ACE2 618-DDC-ABD can also neutralize this variant and hypothesized that it is more sensitive to mouse ACE2 as well as human ACE2. Method(s): The omicron BA.1 SARS-CoV-2 strain was incubated with various concentrations of ACE2 618-DDC-ABD (0-180ug/ml) for 1 hour at 37degreeC. Human ACE2 1-740 and mouse ACE2 1-740 were used as controls at the same concentrations. These mixtures were then used to infect Vero E6 cells. Cells were allowed to grow for 3-4 days until a noticeable cytopathic effect was observed in control wells (0mug/ml soluble ACE2 proteins). Cell numbers were assessed by staining cells with crystal violet and reading absorbance of each well at 595 nm. Values were then normalized to the 0mug/ml control and expressed as a percentage of the mock (no virus) control wells. Result(s): ACE2 618-DDC-ABD (red) neutralized the omicron BA.1 variant at all concentrations tested and to a similar extent as native human soluble ACE2 1-740 (blue) used as control. Native mouse ACE2 1-740 (black) also neutralized infection completely at high concentrations while lower concentrations were less effective as compared to low concentrations of ACE2 618-DDC-ABD or human ACE2 1-740.

Approach to a child with pediatric inflammatory multisystem syndrome with COVID-19 recommendations by the Polish pediatric society expert group and the national consultant in the field of pediatrics

Pediatric inflammatory multisystem syndrome associated with COVID-19 (PIMS) is a new entity, occurring in children and young adults, associated with the SARS-CoV-2 infection. The first cases of PIMS were found in Poland in May 2020. Since October 2020, a significant increase in the incidence of this new disease has been observed in Poland, which reflects the increased incidence of COVID-19 in adults. PIMS development results from dysregulation of the immune system occurring after 2-4 weeks after the SARS-CoV-2 in-fection. Diagnosis is based on a set of clinical features (including fever and features of mul-tiple organ damage) and laboratory abnormalities, with the exclusion of other causes. Most common complications involve cardiovascular system: myocarditis with decreased left ven-tricular ejection fraction, shock and/or coronary artery aneurysms. Mortality is around 2%. Appropriate management, including vital functions support and immunomodulating treat-ment, allows for a quick recovery of the vast majority of patients. The following document is a proposal for diagnostic and therapeutic management of children with suspected PIMS in Poland. Copyright © 2020, Wydawnictwo Czelej Sp. z o.o.. All rights reserved.

Management of a child with COVID-19 recommendations for pediatricians and family medicine physicians in primary healthcare and hospital settings

Recently, a significant increase in the number of patients infected with SARS-CoV-2 has been observed, including children. The available data indicate, that children are less sus-ceptible to SARS-CoV-2 infection compared to adults and may play a lesser role in the transmission of the infection. Children get infected much less frequently than adults, most of them do not have comorbidities, and in 80-90% of cases in children, the clinical course of COVID-19 is mild (oligo-or asymptomatic). The aim of this paper is to discuss the management of a child with COVID-19 in outpatient and inpatient settings. The current options and indications for antiviral therapy (including remdesivir), tociliziumab, and convalescent plasma, were discussed, indicating the limited availability of therapies in children. The mainstay of COVID-19 treatment in most pediatric patients is symptomatic and supportive treatment as well as measures aimed at reducing the spread of SARS-CoV-2 infection. Copyright © 2020, Wydawnictwo Czelej Sp. z o.o.. All rights reserved.

Guidelines for immunization of children following multisystem inflammatory syndrome in children

Multisystem inflammatory syndrome in children (MIS-C) is a late complication of SARS-CoV-2 infection, either symptomatic or asymptomatic. The underlying cause is immunological dysregulation, leading to severe inflammatory processes. Children with MIS-C require hospital treatment, the use of immunomodulating drugs, and often intensive care. COVID-19 vaccination is safe and highly effective in preventing not only severe COVID-19, but also MIS-C in adolescents. However, there are no explicit vaccination recommendations for children who underwent MIS-C. We present a summary of current knowledge on vaccinations against COVID-19 in the context of MIS-C. Moreover, we propose guidance concerning vaccinations for children following MIS-C.

Updated principles of prevention, diagnosis and treatment of COVID-19 in children in Poland - recommendations for paediatricians and family medicine doctors

Since late 2021, we have observed a significant increase in the proportion of children infected with SARS-CoV-2. The course of the disease in children is usually sparsely symptomatic or asymptomatic. However, the predominance of new virus variants makes children more likely to become symptomatically ill and require hospitalisation. This paper aims to update recommendations for managing a child with COVID-19 in out- and inpatient settings. Current options for prevention and antiviral treatment are discussed, noting the limited availability of therapy for children. In most children with COVID-19, the basis for treatment remains symptomatic and supportive therapy and measures to reduce SARS-CoV-2 infection spread.

Approach to a child with pediatric inflammatory multisystem syndrome with covid-19 recommendations by the Polish pediatric society expert group update february 2021

Pediatric inflammatory multisystem syndrome associated with COVID-19 (PIMS) is a new entity, occurring in children and young adults, associated with the SARS-CoV-2 infection. The first cases of PIMS were found in Poland in May 2020. Since October 2020, a signi-ficant increase in this new disease incidence has been observed in Poland, reflecting the increased incidence of COVID-19 in the pediatric population. PIMS development results from dysregulation of the immune system occurring after ca. 4 weeks after the SARS-CoV-2 infection. Diagnosis is based on criteria: a set of clinical features (including fever and features of multiple organ damage) and elevated inflammatory markers, excluding other cau-ses. The most common complications involve the cardiovascular system: heart damage with decreased left ventricular ejection fraction, shock, and coronary artery abnormalities. Mortality is around 2%. Appropriate management, including vital functions support and immunomodulating treatment, allows for a quick recovery of the vast majority of patients. The following document is a guideline for the diagnostic and therapeutic management of children with suspected PIMS in Poland. © 2021, Wydawnictwo Czelej Sp. z o.o.. All rights reserved.

AKI in a mouse model of COVID-19: Therapeutic potential of a novel soluble ACE2 variant

Background: We have previously shown that in the ischemia reperfusion model of AKI kidney ACE2 activity decreases and that the administration of a shorter soluble ACE2 variant markedly attenuates AKI in terms of GFR and kidney histology (Shirazi et al, ASN 2019). Here, we report the effect of a novel ACE2 variant designed to prevent/ treat SARS-CoV-2 in transgenic k18-hACE2 mice infected with a lethal viral dose. Methods: In a BSL-3 facility, transgenic k18-hACE2 mice were infected intranasally with 2×104 PFU SARS-CoV-2. ACE2 1-618-DDC-ABD was administered intranasally and intra-peritoneally 1 hour prior to viral challenge as well as 24 and 48 hours afterwards for a total of 3 doses. Infected control animals received PBS at the same time-points. Kidneys were removed from all animals and examined by light microscopy (LM) histologically and for apoptosis, using PAS and TUNEL staining, respectively. Results: In mice infected with SARS-CoV-2, variable degrees of AKI were found by LM with the following features seen in the few most severe cases: proximal tubule brush border loss (black arrows, figure 1A and B), cytolysis (red arrow, figure 1A), tubular basement membrane disruption (blue arrows, figure 1A and B) and apoptosis (white arrows, figure 1A, B, D and E). In animals treated with ACE2 1-618-DDC-ABD, survival was near 100% and proximal tubular kidney injury was absent or markedly attenuated with less proximal tubule injury (figure 1C) and minimal apoptosis (figure 1F). Glomeruli appeared ischemic (figure 1B, green arrow) but otherwise normal without evidence of thrombosis. Conclusions: Kidneys from a transgenic mouse susceptible to SARS-CoV-2 infection, like patients with COVID-19, displays variable degrees of proximal tubular injury suggesting that this model can be useful to study AKI in COVID-19. Mice that received soluble ACE2 1-618-DDC-ABD protein were essentially protected from AKI suggesting a potential preventative/therapeutic role for soluble ACE2 in this otherwise pharmacologically untreatable devastating disease.

A novel soluble ACE2 protein protects from lethal SARS-CoV-2 infection

Background: Severe acute respiratory syndrome coronavirus type 2 (SARS-CoV-2) uses full-length angiotensin converting enzyme 2 (ACE2) as the main receptor to enter the target cells. A novel soluble ACE2 protein with increased duration of action and binding capacity to exert a decoy effect as a way to intercept SARS-CoV-2 from binding to membrane-bound ACE2 was generated. The protein was administered to a lethal mouse model of COVID-19 to examine its efficacy. Methods: A human soluble ACE2 variant fused with a 5kD albumin binding domain (ABD) was linked via a dimerization motif hinge-like 4-cysteine dodecapeptide to improve binding capacity to the SARS-CoV-2. This novel protein (ACE2 1-618-DDCABD) was administered intranasally and intraperitoneally prior to viral inoculation and on the two following consecutive days. Infected animals were observed for weight, clinical score and mortality in a BSL-3 facility. Upon sacrifice, lung histopathology was evaluated, and viral loads were measured by plaque assay. Results: Infected mice that received ACE2-1-618-DDC-ABD developed only moderate disease assessed by a clinical score, modest weight loss and lung histology. At 6 days, mortality was totally prevented in the treated group (figure), lung histopathology was markedly improved and viral lung and brain titers reduced or non-detectable. By contrast, in untreated animals, lung histology revealed extensive pulmonary alveolar hemorrhage and mononuclear infiltrates, and they all became severely ill and had to be euthanized by day 6/7 (figure). Conclusions: This study demonstrates for the first time in vivo the preventative/ therapeutic efficacy of a soluble ACE2 protein in a preclinical animal model.

ACE2 and TMPRSS2 co-localization in proximal tubules from human kidneys obtained at autopsy from COVID-19 patients

Background: Studies at the single cell level have revealed that the localization of TMPRSS2 is in the distal nephron whereas ACE2 is in the proximal tubule. Since TMPRSS2 is a serine protease necessary for activation of the SARS-CoV-2 S spike protein after it binds to ACE2, this spatial separation would make it difficult to explain how SARS-CoV-2 can infect the kidney. The purpose of this study was to examine the localization of these proteins by immunofluorescence in the kidneys of patients who died from COVID-19. Methods: Human kidney slides from a Northwestern COVID-19 repository were used after IRB approval. Slides from paraffin-embedded blocks were probed with different antibodies (ACE2, TMPRSS2, ACE, NBC-1, Aquaporin 2) for immunofluorescence studies. Mouse kidneys were also examined as additional controls. Results: In mouse kidneys, TMPRSS2 was found in the brush border of proximal tubules and co-localized strongly with ACE2. Similarly, in human kidneys from patients who died from COVID-19, with or without AKI and from non-COVID-19 subjects, ACE2 and TMPRSS2 co-localized in the proximal tubule. TMPRSS2 and ACE2 also co-localized with ACE, a marker of the apical proximal tubule and to a lesser extent with NBC-1, a marker of the basolateral proximal tubule membrane. By contrast, TMPRSS2 and ACE2 did not co-localize with Aquaporin 2, a marker of principal cells in the collecting tubule. Conclusions: In both mouse and human kidneys, ACE2 and TMPRSS2 co-localize in the proximal tubule. In kidneys from patients with COVID-19 with or without AKI obtained at autopsy, both proteins co-localized in the proximal tubule but not in the collecting tubule. Contrary to what was suggested from single-cell mRNA analysis?, the co-localization of both proteins in the proximal tubule would make it possible for the SARS-CoV-2-ACE2 complex to be activated when coronavirus reaches the kidney.

Otorhinolaryngological manifestations of COVID-19 infection

COVID-19 manifests itself in a wide spectrum of clinical symptoms, both in terms of their variety and severity. It can be asymptomatic or abortive, mild, moderate, severe and fulminant, i.e. having a septic course with multiple organ failure and shock. Typical leading symptoms of COVID-19 include: high fever poorly responding to drugs, severe loss of strength, chest pain, dyspnoea, headaches, bone and joint pain and muscle pain, and finally the onset of acute respiratory distress syndrome (ARDS). However, other symptoms not related to the lower respiratory tract involvement are also mentioned as possible in numerous publications. These include gastrointestinal disorders, damage to the central and peripheral nervous system, catarrh of the upper respiratory tract, and dysfunctions of the sensory organs. The aim of this literature review was to determine the frequency of various head and neck dysfunctions that are part of COVID-19. Symptoms of conjunctivitis, nasal mucostis, pharyngits and laryngitis are reported by about 3/4 of patients, albeit they do not always occur at the same time, as in infections caused, for example, by rhinoviruses. Anosmia/hyposmia or ageusia/hypogeusia occur with a similar frequency. Symptoms of damage to the equilibrium system, such as dizziness, are reported by approx. 1/3 of patients, vertigo and hearing loss by approx. 5-6%, of patients, tinnitus by approx. 10% of patients. To date, reports of peripheral paresis of the facial nerve coexisting with COVID-19 are relatively scarce and the symptom is often included in the category of neurological symptoms, the frequency of which also corresponds to about 1/3 of COVID-19 cases. Importantly, both catarrhal and other symptoms listed herein may precede, co-occur or follow the onset of the leading symptoms of COVID-19. They can also be the only symptoms of this disease. This should prompt otorhinolaryngologists to be particularly vigilant in this regard. © 2021 Index Copernicus International. All right reserved.

Approach to a child with Multisystem Inflammatory Syndrome associated with COVID-19. Recommendations by the Polish Paediatric Society Expert Group. Update - February 2021

Multisystem Inflammatory Syndrome in Children (MIS-C) is a new clinical entity occurring in children and young adults, which is associated with the SARS-CoV-2 infection. The first cases of MIS-C were diagnosed in Poland in May 2020. Since October 2020, a significant increase in the incidence of this new disease has been observed in Poland, reflecting the increased incidence of COVID-19 in the paediatric population. MIS-C develops as a result of dysregulation of the immune system occurring 4 weeks after the SARS-CoV-2 infection. Diagnosis is based on the following criteria: a set of clinical features (including fever and signs of multiple organ damage) and elevated inflammatory markers, with exclusion of other causes. The most common complications involve the cardiovascular system: acute myocardial damage with reduced left ventricular ejection fraction, shock, and coronary artery abnormalities and arrhythmias. Mortality in Western Europe and the United States is around 1-2%. Appropriate management, including vital function support and immunomodulatory treatment, allows for a quick recovery in the vast majority of patients. This document is an updated guideline for the diagnostic and therapeutic management of children with suspected MIS-C in Poland. The most important changes concern treatment, steroid therapy, and antiplatelet therapy in particular.

The Perception and Attitudes toward COVID-19 Vaccines: A Cross-Sectional Study in Poland

Vaccine hesitancy is a major threat to the success of COVID-19 vaccination programs. The present cross-sectional online survey of adult Poles (n = 1020) expressing a willingness to receive the COVID-19 vaccine was conducted between February and March 2021 and aimed to assess (i) the general trust in different types of vaccines, (ii) the level of acceptance of the COVID-19 vaccines already in use in Poland (BNT162b2 by BioNTech/Pfizer, mRNA-1273 by Moderna and AZD1222 by Oxford/AstraZeneca) as well as eight vaccines approved outside European Union (EU) or in advanced stages of clinical trials, (iii) level of fear of vaccination against COVID-19, and (iv) main sources of information on COVID-19 vaccination. Among all major vaccine technology, the highest level of trust was observed for the mRNA platform, with a considerable number of surveyed (>20%) not aware of the existence of vaccines produced using the traditional approach (inactivated and live attenuated vaccines). The age of participants was the main factor differentiating the level of trust in a particular vaccine type. Both BNT162b and mRNA-1273 received a high level of acceptance, contrary to AZD1222. From eight vaccines unauthorized in the EU at the moment of study, the CVnCoV (mRNA;CureVac) was met with the highest level of trust, followed by Ad26.COV2.S (vector;Janssen/Johnson&Johnson) and NVX-CoV2373 (protein;Novavax). Sputnik V (vector;Gamaleya Research Institute) was decidedly the least trusted vaccine. The median level of fear (measured by the 10-point Likert-type scale) in the studied group was 4.0, mostly related to the risk of serious allergic reactions, other severe adverse events and unknown long-term effects of vaccination. Female, individuals with a lower level of education and those not seeking any information on the COVID-19 vaccines revealed a higher fear of vaccination. Experts' materials were the major source of information on COVID-19 vaccines in the studied group. The study shows the level of trust in COVID-19 vaccines can vary much across the producers while the mRNA vaccines are received with a high level of acceptance. It also emphasizes the need for effective and continuous science communication when fighting the pandemic as it may be an ideal time to increase the general awareness of vaccines.

Kidney and lung ACE2 expression after an ace inhibitor or an angiotensin ii receptor blocker: implications for COVID-19

Background: There have been concerns that ACE inhibitors and Ang II receptor blockers may cause an increase in full length (FL) membrane bound ACE2, the main receptor for SARs-CoV-2, that could enhance the risk and worsen the clinical course of COVID -19. Information on the impact of ACE deficiency and AT1 blockade on ACE2 expression at target sites is required to understand this issue. Methods: Kidneys from two genetic models of kidney ACE ablation and mice treated with captopril or telmisartan were used to examine ACE2 in isolated kidney and lung membranes. Results: In global ACE KO mice, ACE2 protein abundance in kidney membranes was reduced to 42 % of wild type, p < 0.05. In ACE 8/8 mice that over-express cardiac ACE protein but has no kidney ACE expression, ACE2 protein in kidney membranes wasalso decreased (38 % of the WT, p<0.01). In kidney membranes from mice that received captopril or telmisartan for 2 weeks there was a reduction in ACE2 protein to the level of 37%, p<0.01 and 76%, p <0.05 of that of vehicle control mice, respectively. In lung membranes the expression of ACE2 was very low and not detected by western blotting but no significant differences in terms of ACE2 activity could be detected in mice treated with captopril (118% of control) or telmisartan (93% of control). Conclusions: Genetic kidney ACE deficiency, suppressed ACE enzyme activity by Captopril or blockade of the AT1 receptor with telmisartan are all associated with a decrease in ACE2 expression in kidney membranes. These findings altogether suggest that ACE2 protein abundance at two potential target sites for SARS-CoV-2 infection is decreased or unaffected by RAS blockers. Since these medications do not increase ACE2 expression in lung or kidney epithelia, we conclude that they likely would not pose a risk for increased susceptibility to COVID -19.