Evaluation of the safety profile and therapeutic efficacy of remdesivir in children with SARS-CoV-2 infection - a single-center, retrospective, cohort study.

Despite 3.5 years of the SARS-CoV-2 pandemic, we still lack effective drugs against COVID-19. The first and most widely used drug, remdesivir, has not yet been shown to be effective in adults. Even less is known about its effectiveness in children. Therefore, the aim of this retrospective study was to evaluate the safety and efficacy of remdesivir in pediatric patients with COVID-19 hospitalized in one medical center. The medical records of 328 children with COVID-19 were analyzed. Analysis was performed on the subgroups of children treated and not treated with remdesivir. Clinical data on general health, course of COVID-19 and treatment received were analyzed. Remdesivir was administered to 64 children, 16 to treat severe or critical illness and 48 because of the presence of risk factors to prevent progression to severe COVID-19. In children with severe COVID-19, remdesivir did not reduce the mortality rate. However, in patients with milder disease and risk factors, the drug significantly reduced the risk of progression to severe disease. Among adverse events, only mild aminotransferase elevations were observed in 4 patients, but none of these required discontinuation of treatment. CONCLUSIONS: Remdesivir is a safe treatment option for children with COVID-19. However, the efficacy of this therapy is still uncertain. It appears that in children with asymptomatic to moderate COVID-19 and risk factors for severe disease, remdesivir could be an effective method of prophylaxis. However, its efficacy in controlling severe disease is questionable and requires further study. WHAT IS KNOWN: • There are still no effective drugs to combat COVID-19, and the efficacy of the widely used remdesivir in adults is controversial. • All recommendations and guidelines on the use of remdesivir in the pediatric population are based mainly on clinical trials in adults. WHAT IS NEW: • Remdesivir is a safe treatment for COVID-19 in the pediatric population. • In children with asymptomatic to moderate COVID-19 and risk factors for severe disease, remdesivir could be an effective drug to prevent disease progression. However, its efficacy in treating severe disease in children needs further exploration.

Immune Response to SARS-CoV-2 Infections in Children with Secondary Immunodeficiencies.

BACKGROUND AND PURPOSE: It is a matter of research, whether children with immunodeficiencies are able to generate an effective immune response to prevent SARS-CoV-2 reinfection. This study aimed to evaluate and compare the seroconversion rates and changes of lymphocyte subsets during COVID-19 in immunocompetent children and those with secondary immunodeficiencies. METHODS: In 55 children - 28 immunocompromised and 27 immunocompetent - hospitalized with confirmed SARS-CoV-2 infection, the level of IgG antibodies against the Spike protein was determined on two to three occasions. In those children from the study group whose immunosuppressive treatment did not alter during the study (n = 13) and in selected children from the control group (n = 11), flow cytometric evaluation of lymphocyte subsets was performed twice - 2 weeks and 3 months post-infection. RESULTS: Seroconversion reached 96.3% in both studied groups; however, the immunocompromised cohort achieved lower titers of detectable anti-S antibodies. There was no correlation between seroconversion or titers of antibodies and the total number of lymphocytes or their subsets. In the immunocompetent cohort, we reported a significant decrease in NK cells during the infection. In this group and the entire study population, a positive correlation was noticed between the CD4 + /CD8 + T cell ratio and the severity of COVID-19 pneumonia. CONCLUSIONS: Children with secondary immunodeficiencies seroconvert in equal percentages but with a significantly lower titer of anti-S antibodies compared to their immunocompetent peers. The lower number of NK cells in the immunocompetent cohort may result from their participation in antiviral immunity, whereas reduced CD4 + /CD8 + T cell ratios among immunocompromised children may be a protective factor against a severe COVID-19.

Long-COVID in immunocompromised children.

Coronavirus disease 2019 (COVID-19) can lead to an illness characterized by persistent symptoms which affect various organs and systems, known as long-COVID. This study aimed to assess the prevalence and clinical characteristics of long-COVID in children with immunodeficiency, in comparison to those without. A self-constructed questionnaire was created, which included questions regarding the child's general health, the course of their COVID-19, their symptoms of long-COVID and its impact on their daily functioning, the diagnosis of multisystem inflammatory syndrome (MIS-C), and vaccination status. The questionnaire was completed by parents of 147 children - 70 children with a diagnosis of immunodeficiency (47.6%) and 77 who were immunocompetent (52.4%). Immunocompetent children were more significantly affected by long-COVID than those immunocompromised. Its prevalence in the first 12-week post-infection was 60.0% and 35.7% in these groups, respectively. Beyond this period, these percentages had dropped to 34.6% and 11.43%, respectively. Children who were immunocompetent reported more often symptoms of fatigue, reduced exercise tolerance, and difficulty concentrating. Meanwhile, there was a slight increase in complaints of gastrointestinal symptoms in immunocompromised patients. The risk of developing long-COVID increased with age and COVID-19 severity in both groups. Furthermore, the daily activities of immunocompetent children were limited more frequently (41.8%) than for those who were immunocompromised (25%). CONCLUSIONS: Although immunocompromised children experienced long-COVID, its prevalence and impact on daily functioning were significantly lower than among immunocompetent children. However, as the pathomechanisms of long-COVID are not yet fully understood, it is not currently possible to fully explain these findings. WHAT IS KNOWN: • Long COVID is characterized by persistent symptoms following COVID-19, which can affect various tissues and organs, as well as mental health. • Due to the similar course of COVID-19 - mainly mild or asymptomatic - among children with and without immunodeficiency, the question arises, over whether the prevalence and severity of long-COVID is also similar in both groups. WHAT IS NEW: • Immunocompromised children also suffer from long-COVID, but the prevalence is significantly lower than in the immunocompetent group of children. • The potential causes of less frequent and milder long-COVID in this group may be the milder course of COVID-19 and the state of reduced immunity protecting against neuroinflammation.

Mucopolysaccharidosis-Plus Syndrome: Report on a Polish Patient with a Novel VPS33A Variant with Comparison with Other Described Patients.

Eleven patients from Yakutia with a new lysosomal disease assumed then as mucopolysaccharidosis-plus syndrome (MPS-PS) were reported by Gurinova et al. in 2014. Up to now, a total number of 39 patients have been reported; in all of them, the c.1492C>T (p.Arg498Trp) variant of the VPS33A gene was detected. Here, we describe the first Polish MPS-PS patient with a novel homozygous c.599G>C (p.Arg200Pro) VPS33A variant presenting over 12 years of follow-up with some novel clinical features, including fetal ascites (resolved spontaneously), recurrent joint effusion and peripheral edemas, normal growth, and visceral obesity. Functional analyses revealed a slight presence of chondroitin sulphate (only) in urine glycosaminoglycan electrophoresis, presence of sialooligosaccharides in urine by thin-layer chromatography, and normal results of lysosomal enzymes activity and lysosphingolipids concentration in dried blood spot. The comparison with other MPS-PS described cases was also provided. The presented description of the natural history of MPS-PS in our patient may broaden the spectrum of phenotypes in this disease.

Eosinophilic cystitis and cholangitis - systemic disease triggered by mycobacterium tuberculosis?

Eosinophilic cystitis (EC) is a rare inflammatory disorder of the urinary tract characterized by infiltration of bladder with eosinophils. The cause remains unclear, immunological mechanisms have been implicated in pathogenesis. Potential etiological factors include: tumors, allergy, parasitic infections, trauma. The disease may have a variable course, from a mild self-limiting, through common symptoms like: dysuria, hematuria, abdominal pain, tumor, to severe renal failure, with eosinophilic infiltration of the other organs and systemic complications. Treatment depending on disease severity and etiology is pharmacological and/or surgical. Here we report a case of a previously healthy 16-year old girl with inflammatory tumor in the liver hilum infiltrating extrahepatic biliary tract who developed three months later haematuria with acute dysuric signs and renal failure. Based on histopathological findings diagnosis of eosinophilic cystitis was established. Tests for Mycobacterium tuberculosis were positive. To our knowledge, EC association with cholangitis and tuberculosis have never been reported before.

Eosinophilic cystitis and cholangitis - systemic disease triggered by mycobacterium tuberculosis?

Eosinophilic cystitis (EC) is a rare inflammatory disorder of the urinary tract characterized by infiltration of bladder with eosinophils. The cause remains unclear, immunological mechanisms have been implicated in pathogenesis. Potential etiological factors include: tumors, allergy, parasitic infections, trauma. The disease may have a variable course, from a mild self-limiting, through common symptoms like: dysuria, hematuria, abdominal pain, tumor, to severe renal failure, with eosinophilic infiltration of the other organs and systemic complications. Treatment depending on disease severity and etiology is pharmacological and/or surgical. Here we report a case of a previously healthy 16-year old girl with inflammatory tumor in the liver hilum infiltrating extrahepatic biliary tract who developed three months later haematuria with acute dysuric signs and renal failure. Based on histopathological findings diagnosis of eosinophilic cystitis was established. Tests for Mycobacterium tuberculosis were positive. To our knowledge, EC association with cholangitis and tuberculosis have never been reported before.

Cerebrospinal fluid eosinophilia in a child with neuroborreliosis.

Cerebrospinal fluid eosinophilia is rare and usually associated with eosinophilic meningitis caused by helminthic infections. It is also observed in bacterial or fungal meningitis (syphilis, tuberculosis, coccidioidomycosis), in patients with malignancies, ventriculoperitonial shunts, hypereosinophilic syndrome or allergy to some medications. Here we present a case of an 8-year-old boy admitted with fever and clinical signs of meningitis. Cerebrospinal fluid (CSF) analysis showed marked eosinophilia. Basing on further serological CSF testing the diagnosis of borreliosis was established. Cerebrospinal fluid eosinophilia in Borrelia burgdorferi infection has never been reported before.

FCGR2/3 polymorphisms are associated with susceptibility to Kawasaki disease but do not predict intravenous immunoglobulin resistance and coronary artery aneurysms.

Introduction: Kawasaki disease (KD) is a pediatric vasculitis that can result in coronary artery aneurysm (CAA) formation, which is a dangerous complication. Treatment with intravenous immunoglobulin (IVIg) significantly decreases the risk of CAA, possibly through competitive binding to Fc-gamma receptors (FcγRs), which reduces the binding of pathological immune complexes. However, ~20% of children have recrudescence of fever and have an increased risk of CAA. Therefore, we aimed to identify genetic markers at the FCGR2/3 locus associated with susceptibility to KD, IVIg resistance, or CAA. Materials and methods: We investigated the association of single-nucleotide polymorphisms (SNPs) and copy number variations (CNVs) at the FCGR2/3 locus with KD susceptibility, IVIg resistance, and CAA risk using a family-based test (KD susceptibility) and case-control analyses (IVIg resistance and CAA risk) in different cohorts, adding up to a total of 1,167 KD cases. We performed a meta-analysis on IVIg resistance and CAA risk including all cohorts supplemented by previous studies identified through a systematic search. Results: FCGR2A-p.166His was confirmed to be strongly associated with KD susceptibility (Z = 3.17, p = 0.0015). In case-control analyses, all of the investigated genetic variations at the FCGR2/3 locus were generally not associated with IVIg resistance or with CAA risk, apart from a possible association in a Polish cohort for the FCGR3B-NA2 haplotype (OR = 2.15, 95% CI = 1.15-4.01, p = 0.02). Meta-analyses of all available cohorts revealed no significant associations of the FCGR2/3 locus with IVIg resistance or CAA risk. Discussion: FCGR2/3 polymorphisms are associated with susceptibility to KD but not with IVIg resistance and CAA formation. Currently known genetic variations at the FCGR2/3 locus are not useful in prediction models for IVIg resistance or CAA risk.

[Secondary hemophagocytic syndromes]. / Wtórne zespoly hemofagocytarne--aktualny problem interdyscyplinarny.

Hemophagocytic lymphohistiocytosis (HLH) is a life-threatening extreme whole body inflammatory state. It results from the pathological hyperactivation of the immune system, because of congenital or acquired abnormalities of cytotoxicity and NK or T cells. Uncontrolled stimulation of lymphocytes and macrophages lead to hypercytokinemia, organ infiltration by these cells and multiple organ failure. There are genetic HLH and secondary HLH, associated with infections, autoimmune disorders, malignancies. The frequency of the secondary form is difficult to estimate because of the wrong and difficult diagosis. The clinical course is often insidious and nonspecific. Symptoms are varied. The most important are: unremitting fever, hepatosplenomegaly. Generalized edema, rash, lymphadenopathy may occur. Liver failure, respiratory, circulatory and multiple organ failure could develop in a very short time. Most common abnormalities in additional tests are: cytopenias, hypofibrinogenaemia, hypertriglyceridaemia, hyperferritinaemia, hypertransaminasaemia, elevated parameters of inflammation (excepting lowering erythrocyte sedimentaion rate). Criteria for diagnosis and therapeutic protocols referto the genetic forms of HLH. Currently, there are no guidelines for secondary HLH. Diagnostic and therapeutic difficulties also arise from clinical picture, similar as in the systemic inflammatory response syndrome, sepsis, multiple organ dysfunction syndrome. We present the clinical presentation, diagnostic pitfalls and treatment of secondary HLH, based on a review of the current literature and our own observations.

Lipoid pneumonia--a case of refractory pneumonia in a child treated with ketogenic diet.

Lipoid pneumonia (LP) is a chronic inflammation of the lung parenchyma with interstitial involvement due to the accumulation of endogenous or exogenous lipids. Exogenous LP (ELP) is associated with the aspiration or inhalation of oil present in food, oil-based medications or radiographic contrast media. The clinical manifestations of LP range from asymptomatic cases to severe pulmonary involvement, with respiratory failure and death, according to the quantity and duration of the aspiration. The diagnosis of exogenous lipoid pneumonia is based on a history of exposure to oil and the presence of lipid-laden macrophages on sputum or bronchoalveolar lavage (BAL) analysis. High-resolution computed tomography (HRCT) is the imaging technique of choice for evaluation of patients with suspected LP. The best therapeutic strategy is to remove the oil as early as possible through bronchoscopy with multiple BALs and interruption in the use of mineral oil. Steroid therapy remains controversial, and should be reserved for severe cases. We describe a case of LP due to oil aspiration in 3-year-old girl with intractable epilepsy on ketogenic diet. Diagnostic problems were due to non-specific symptoms that were mimicking serious infectious pneumonia. A high index of suspicion and precise medical history is required in cases of refractory pneumonia and fever unresponsive to conventional therapy. Gastroesophageal reflux and a risk of aspiration may be regarded as relative contraindications to the ketogenic diet. Conservative treatment, based on the use of oral steroids, proved to be an efficient therapeutic approach in this case.

Different Course of SARS-CoV-2 Infection in Two Adolescents With Other Immunosuppressive Factors.

Even after two years of the Coronavirus Disease 2019 (COVID-19) pandemic, despite known risk factors, we are still unable to predict the severity of the infection in specific patients. Due to the contradictory data, the protective role of immunosuppression in preventing the severe course of the infection remains uncertain. Therefore, we want to discuss the influence of several immunosuppressive factors on the COVID-19 pattern in children, based on two case reports regarding 17-year-old boys with other immunosuppressive factors and a completely different course of the disease. The first patient suffered from AIDS, syphilis and primary central nervous system B-cell lymphoma, treated with radiotherapy. He experienced a light path of the infection, presenting only periodically appearing cough with no X-ray inflammatory changes. Nevertheless, due to the risk of severe COVID-19 and transient hypoxia, remdesivir was administered. He remained in a generally good condition and his follow-up did not reveal any noticeable complications. The second patient was characterised by Down syndrome, obesity, polyarteritis nodosa and chronic immunosuppressive therapy. He developed massive pneumonia, required treatment in the intensive care unit with the use of mechanical ventilation, remdesivir and anakinra. Despite the initial improvement of his general condition, including the degree of lung involvement and respiratory function, he developed an intracerebral haemorrhage, leading to brain herniation and ultimately death. In conclusion, HIV infection, oncological and immunosuppressive treatment do not seem to predispose to the severe course of COVID-19, whereas Down syndrome and obesity do.

Clinical characteristics of Kawasaki disease in Polish children: A retrospective study.

BACKGROUND: Kawasaki disease (KD), an acute, generalized vasculitis, is associated with an increased risk of coronary heart disease and is the most common cause of acquired heart disease in childhood. The incidence of KD is increasing worldwide. AIMS: Our study aims to analyze KD's clinical course in children and to evaluate risk factors for persistent changes in coronary vessels after 6-8 weeks of treatment. METHODS: The retrospective analysis included patients with KD hospitalized in a single tertiary carehospital. The diagnosis, as well as treatment, were based on the current worldwide treatment standards. The clinical course, selected laboratory parameters, the treatment effect, and following cardiac complications were analyzed in different age groups. RESULTS: In the years 2006-2019, 140 patients aged from two months to 16 years: 52 girls and 88 boys, were diagnosed with KD. Coronary artery aneurysms (CAA) at weeks 6-8 of disease were found in 16% of patients. Boys and infants were more likely to develop aneurysms at weeks 6-8 of the disease (P = 0.045; P = 0.03; respectively). The CAA frequency was related to the atypical course (P = 0.02), late diagnosis (P = 0.04), presence of changes in the coronary arteries at the time of diag nosis (P<0.001), immunoglobulin resistance (P = 0.002), a lower hemoglobin concentraction (P<0.001), and a higher platelet count (P = 0.02). There were 28% of patients resistant to first-line time treatment. In this group, we found CAA in 31% of children. CONCLUSIONS: We found that late diagnosis, low hemoglobin level, high platelet count, CAA presence at diagnosis, atypical course of KD, and resistance to intravenous immunoglobulins are predictors of CAA after 6-8 weeks in KD patients.

Clinical characteristics of children with MIS-C fulfilling classification criteria for macrophage activation syndrome.

Background: Macrophage activation syndrome (MAS) is a potentially life-threatening complication of various inflammatory disorders, including multisystem inflammatory syndrome in children (MIS-C). MIS-C refractory to treatment should raise suspicion of MAS, which can be fatal if a definitive diagnosis is delayed. Unfortunately, there is a lack of data on MAS in children with MIS-C. Objective: Our study aims to analyze the risk factors for the development of MAS in MIS-C, its clinical course and response to treatment, and identify predictive factors for pediatric intensive care. Material and methods: We analyzed data from the Polish MIS-C registry of the MultiOrgan Inflammatory Syndromes COVID-19 Related Study. Patients were diagnosed according to the WHO MIS-C definition and treated according to national guidelines (Polish Pediatric Society) based on international consensus. MAS definition was based on 2016 Classification Criteria for Macrophage Activation Syndrome Complicating Systemic Juvenile Idiopathic Arthritis. Results: Two-hundred and seventy four children met the study inclusion criteria. Fifty-nine patients fulfilled MAS classification criteria, nine of which required admission to the pediatric intensive care unit (PICU). MIS-C patients with MAS were significantly older than patients without MAS (median 11.2 vs. 8.1 years). Multivariable analysis showed that age, symptoms characteristic of atypical Kawasaki disease, and skin erosions were significant factors associated with MAS in MIS-C patients. Analysis of laboratory parameters showed that on admission, MIS-C patients with MAS had significantly lower median lymphocyte and platelet counts, albumin and sodium levels, and higher median levels of C-reactive protein, procalcitonin, ferritin, D-dimers, triglycerides, serum creatinine, urea, and γ-glutamyl transpeptidase, and neutrophil count. Multivariate analysis showed that higher procalcitonin, ferritin, and fibrinogen levels at admission were predictive of MAS. Only elevated troponin level was a factor indicating a requirement of PICU hospitalization for children with MAS. MIS-C patients fulfilling MAS criteria were treated more often with intravenous immunoglobulins and steroids than children without MAS. Children with MAS more often required mechanical ventilation. None of the patients required biological agents. Conclusions: The clinical course of MAS in MIS-C seems milder, treatment less aggressive, and the prognosis better than expected based on the current knowledge on MAS complicating other rheumatological diseases.

Anti-inflammatory Treatment of Kawasaki Disease: Comparison of Current Guidelines and Perspectives.

Kawasaki disease (KD), an acute, generalized vasculitis, is associated with an increased risk of coronary heart disease and is the most common cause of acquired heart disease in childhood. The incidence of KD is increasing worldwide. There are numerous international treatment guidelines. Our study aims to perform the first one so far comparison of them. While the gold standard therapy remains still the same (intravenous immunoglobulins and aspirin), there is currently a lack of evidence for choosing optimal treatment for high-risk patients and refractory KD. In this review, we also discuss the treatment of complications of KD and Kawasaki-like phenotypes, present an anti-inflammatory treatment in the light of new scientific data, and present novel potential therapeutic targets for KD.

Association Between rs12037447, rs146732504, rs151078858, rs55723436, and rs6094136 Polymorphisms and Kawasaki Disease in the Population of Polish Children.

Background: Kawasaki disease (KD) is an acute self-limited febrile vasculitis that mainly affects young children. Coronary artery involvement is the most serious complication in children with KD. It is currently the leading cause of acquired cardiac disease in children from developed countries. Literature data indicate a significant role of genetic susceptibility to KD. Objective: The aim of this study was to perform the first Genome-Wide Association Study (GWAS) in a population of Polish children with KD and identify susceptible genes involved in the pathogenesis of KD. Materials and Methods: The blood samples of Kawasaki disease patients (n = 119) were collected between 2016 and 2020, isolated and stored at the Department of Pediatrics, Nutrition and Metabolic Diseases, Children's Memorial Health Institute in Warsaw. The control group was based on Polish donors (n = 6,071) registered as the POPULOUS collection at the Biobank Lab of The Department of Molecular Biophysics in University of Lodz. DNA samples were genotyped for 558,231 Single Nucleotide Polymorphisms (SNPs) using the 24 × 1 Infinium HTS Human Core Exome microarrays according to the protocol provided by the manufacturer. In order to discover and verify genetic risk-factors for KD, association analysis was carried out using PLINK 1.9. Results: Of all 164,395 variants, 5 were shown to occur statistically (padjusted < 0.05) more frequent in Kawasaki disease patients than in controls. Those are: rs12037447 in non-coding sequence (padjusted = 8.329 × 10-4, OR = 8.697, 95% CI; 3.629-20.84) and rs146732504 in KIF25 (padjusted = 0.007354, OR = 11.42, 95% CI; 3.79-34.43), rs151078858 in PTPRJ (padjusted = 0.04513, OR = 8.116, 95% CI; 3.134-21.01), rs55723436 in SPECC1L (padjusted = 0.04596, OR = 5.596, 95% CI; 2.669-11.74), rs6094136 in RPN2 (padjusted = 0.04755, OR = 10.08, 95% CI; 3.385-30.01) genes. Conclusion: Polymorphisms of genes KIF25, PTRPJ, SPECC1L, RNP2 may be linked with the incidence of Kawasaki disease in Polish children.

Exome Sequencing Reveals Novel Variants and Expands the Genetic Landscape for Congenital Microcephaly.

Congenital microcephaly causes smaller than average head circumference relative to age, sex and ethnicity and is most usually associated with a variety of neurodevelopmental disorders. The underlying etiology is highly heterogeneous and can be either environmental or genetic. Disruption of any one of multiple biological processes, such as those underlying neurogenesis, cell cycle and division, DNA repair or transcription regulation, can result in microcephaly. This etiological heterogeneity manifests in a clinical variability and presents a major diagnostic and therapeutic challenge, leaving an unacceptably large proportion of over half of microcephaly patients without molecular diagnosis. To elucidate the clinical and genetic landscapes of congenital microcephaly, we sequenced the exomes of 191 clinically diagnosed patients with microcephaly as one of the features. We established a molecular basis for microcephaly in 71 patients (37%), and detected novel variants in five high confidence candidate genes previously unassociated with this condition. We report a large number of patients with mutations in tubulin-related genes in our cohort as well as higher incidence of pathogenic mutations in MCPH genes. Our study expands the phenotypic and genetic landscape of microcephaly, facilitating differential clinical diagnoses for disorders associated with most commonly disrupted genes in our cohort.

Pediatric Inflammatory Multisystem Syndrome (PIMS) Did Occur in Poland during Months with Low COVID-19 Prevalence, Preliminary Results of a Nationwide Register.

Pediatric inflammatory multisystem syndrome (PIMS) is a new entity in children, likely associated with previous coronavirus disease 19 (COVID-19) infection. Most of the reports about PIMS come from countries particularly hit by the COVID-19 pandemic. Our aim was to investigate the nature of inflammatory syndromes in Poland (country with low COVID-19 prevalence) and to perceive the emergence of PIMS in our country. On 25 May 2020, we launched a nationwide survey of inflammatory syndromes in children for retrospective (since 4 March 2020) and prospective data collection. Up to 28 July, 39 reported children met the inclusion criteria. We stratified them according to age (<5 and ≥ 5 years old) and COVID-19 status. The majority of children had clinical and laboratory features of Kawasaki disease, probably non-associated with COVID-19. However, children ≥5 years of age had PIMS characteristics, and nine children had COVID-19 confirmation. This is, to our knowledge, the first report of the PIMS register from a country with a low COVID-19 prevalence, and it proves that PIMS may emerge in any area involved in the COVID-19 pandemic. In a context of limited COVID-19 testing availability, other risk factors of PIMS, e.g., older age, should be considered in the differential diagnosis of inflammatory syndromes in children.

The influence of various therapeutic regimens on early clinical and laboratory response and outcome of children with secondary hemophagocytic lymphohistiocytosis.

INTRODUCTION: Secondary hemophagocytic lymphohistiocytosis (sHLH) is a life-threatening syndrome of severe hyperinflammation which is often triggered by infection or autoimmune disease (macrophage activation syndrome - MAS). The aim of our study was to assess the frequency of sHLH/MAS in children treated in our institution and to compare the effectiveness of various therapeutic interventions. MATERIAL AND METHODS: Between 2005 and 2013, 24 children (age: 1-17 years) were consecutively treated for sHLH/MAS. Therapy was based on glucocorticoids (GCs) in high or standard doses (hd-GCs or sd-GCs), intravenous immunoglobulin (IVIG), and cyclosporin A (CyA). A comparison of selected laboratory and clinical parameters during the first 72 h of treatment and after a week from the last intervention applied in the first 72 h after diagnosis was performed retrospectively. RESULTS: The majority of patients (14/24, 58%) suffered from sHLH/MAS in the course of an autoimmune disease (12 patients diagnosed with a systemic form of juvenile idiopathic arthritis). We found with a confidence level of 95% that the application of hd-GCs in the first 24 h caused rapid alleviation of fever, reduction of hepatosplenomegaly, and an increase in thrombocytes and s-fibrinogen concentrations. The use of combination therapy with hd-GCs, IVIG, and CyA in the first 72 h caused a faster increase in s-fibrinogen. All patients survived and were alive at the follow-up of 1-8 years. CONCLUSIONS: The results indicate that treatment of sHLH/MAS based on hd-GCs, CyA and IVIG is an effective therapy in children.

Congenital disorder of glycosylphosphatidylinositol (GPI)-anchor biosynthesis--The phenotype of two patients with novel mutations in the PIGN and PGAP2 genes.

BACKGROUND: Glycosylphosphatidylinositol (GPI)-anchor deficiencies are a new subclass of congenital disorders of glycosylation. About 26 genes are involved in the GPI-anchor biosynthesis and remodeling pathway, of which mutations in thirteen have been reported to date as causative of a diverse spectrum of intellectual disabilities. Since the clinical phenotype of these disorders varies and the number of described individuals is limited, we present new patients with inherited GPI-anchor deficiency (IGD) caused by mutations in the PGAP2 and PIGN genes. PATIENTS AND METHODS: The first girl presented with profound psychomotor retardation, low birth parameters, and chest deformities already existing in neonatal period. The disease course was slowly progressive with severe hypotonia, chronic fever, and respiration insufficiency at the age of 6. The second girl showed profound psychomotor retardation, marked hypotonia, and high birth weight (97 centile). Dysmorphy was mild or absent in both girls. Whole exome sequencing revealed novel variants in the genes PGAP2 (c.2T>G and c.221G>A) and PIGN (c.790G>A and c.932T>G). Impaired GPI binding were was subsequently uncovered, although the hyperactivity of alkaline phosphatase (a GPI-anchored protein) occurred only in first case. CONCLUSIONS: Based on our results we can conclude that: 1. GPI-anchor biosynthesis disorders may represent a relatively frequent and overlooked metabolic defect; 2. The utility of GPI binding assessment as a screening test for this group of rare diseases requires further studies.

Gastroenterological complications of Anderson-Fabry disease.

Fabry disease is a multisystemic X-linked lysosomal storage disorder, caused by the partial or complete deficiency of alpha-galactosidase A activity. The storage of glycosphingolipids in the vascular endothelium and in various tissues can lead to a broad spectrum of clinical manifestations. Renal failure, cardiovascular disease, and strokes are the main causes of morbidity and mortality. Gastrointestinal symptoms, although common, are often under-reported in the literature. This review covers the gastroenterological aspects of Fabry disease.