Publications by authors named "Katarzyna Mazur-Melewska"

Background: Group A Streptococci (GAS) may cause infections of the pharynx and soft tissues and invasive infections in children (iGAS). A significant increase in severe iGAS infections has been reported in Europe since the fall of 2022.

Objectives: This retrospective study aims to analyse clinical data of children with invasive and non-invasive GAS infections in the post-COVID-19 pandemic era, searching for predisposing factors to developing invasive infections.

View Article and Find Full Text PDF
Article Synopsis
  • Lyme borreliosis (LB) is a significant health issue, causing numerous infections in children, and this study is the first to link it with environmental factors.
  • Researchers analyzed medical records of 196 children diagnosed with LB in Poland and found a positive correlation between LB cases and environmental elements like deer density, broadleaved forest coverage, and urbanization.
  • Results indicated that LB cases in children increased with urbanization and forest coverage, particularly in males, with a notable rise in cases from 2017 to 2021, highlighting the relationship between deer density and infection risk.
View Article and Find Full Text PDF

This study investigates the impact of Epstein-Barr virus (EBV) infection on children's proteomes across different phases of the disease, utilising seventy-nine blood samples categorised into three groups: EBV-naive patients, acute infectious mononucleosis (IM) cases, and convalescents followed up for 12 months post-IM. The aim is to identify proteins influenced by EBV infection, shedding light on the chronic processes triggered by the virus. The results reveal thirty-nine proteins distinguishing between naive patients and those with IM, including actin, lumican, peroxiredoxin-2, fibulin-1, gelsolin, and alpha-2-macroglobulin, which are involved in immune responses, cell adhesion, and inflammation.

View Article and Find Full Text PDF
Article Synopsis
  • The Poxviridae family consists of a variety of viruses, divided into two subfamilies: Chordopoxvirinae for vertebrates and Entomopoxvirinae for insects, with only three species that can infect humans.
  • Post-smallpox eradication in 1980, mass vaccination was stopped, leaving many, especially children, unprotected against Orthopoxvirus (OPV).
  • This chapter aims to explore the causes, symptoms, diagnosis, and treatment of Poxviridae infections in pediatric populations.
View Article and Find Full Text PDF

Autism spectrum disorder (ASD) is a complex neurodevelopmental condition characterized by several core symptoms: restricted interests, communication difficulties, and impaired social interactions. Many ASD children experience gastrointestinal functional disorders, impacting their well-being. Emerging evidence suggests that a gut microbiota imbalance may exacerbate core and gastrointestinal symptoms.

View Article and Find Full Text PDF

Purpose: The aim of the study was to analyse magnetic resonance imaging (MRI) of paediatric patients referred because of back pain.

Material And Methods: The retrospective analysis included the medical records of 328 patients referred in 2020-2022 to the Department of Paediatric Radiology for spine examination. The criterion for inclusion in the analysed group was back pain as the dominant symptom.

View Article and Find Full Text PDF

Neuroborreliosis is a form of Lyme Borreliosis (LB) that affects various structures of the central and peripheral nervous system. Although most cases of LB can be cured with a course of antibiotics, some children can present prolonged symptoms, which may constitute post-treatment Lyme disease syndrome (PTLDS). The aim of our analysis was the long-term observation of children with NB and the determination of their risk of PTLDS.

View Article and Find Full Text PDF

Background: This study aimed to analyze the differences in the epidemiologic and clinical characteristics of coronavirus disease 2019 (COVID-19) in children hospitalized in 2021, when the severe acute respiratory syndrome coronavirus 2 variants B.1.1.

View Article and Find Full Text PDF

This study aimed to analyze the differences in severity and clinical characteristics of COVID-19 in infants hospitalized in Poland in 2021, when the dominance of variants of concern (VOCs) alpha and delta was reported, compared to 2020, when original (wild) SARS-CoV-2 was dominant (III-IV vs. I-II waves of the pandemic, respectively). In addition, the influence of the presence of comorbidities on the clinical course of COVID-19 in infants was studied.

View Article and Find Full Text PDF

Various primarily non-autoimmune neurological disorders occur synchronously with autoantibodies against tissues in the nervous system. We aimed to assess serum and cerebrospinal fluid (CSF) autoantibodies in children with neurologic disorders. To find new diagnostic tools, we compared the laboratory and clinical findings between the distinguished groups.

View Article and Find Full Text PDF
Article Synopsis
  • * The skin symptoms of Lyme borreliosis can vary greatly, with typical lesions aiding diagnosis and atypical ones complicating it, especially if the patient doesn't recall a tick bite.
  • * This study highlights various skin manifestations of Lyme disease in children, shares practical recognition strategies, and discusses diagnostic tips for different forms of the condition.
View Article and Find Full Text PDF

The gut-brain axis and the intestinal microbiota have been an area of an intensive research in the last few years. However, it is not a completely novel area of interest for physicians and scientists. From the earliest centuries, both professionals and patients turned their attention to the gastrointestinal system in order to find the root of physical and mental disturbances.

View Article and Find Full Text PDF

Objectives: Multisystem inflammatory syndrome in children (MIS-C) is the result of an immune response triggered by a previous exposure to SARS-CoV-2. The clinical presentation of MIS-C overlaps with other life-threatening bacterial infections, in which antimicrobials are the mainstay therapy. The aim of study was to describe the use of antibiotics in children with MIS-C in Poland.

View Article and Find Full Text PDF

The identification of central nervous system inflammation etiology leads to adjusted therapy. We analyzed the potential inflammatory and neuro-axonal damage markers in children. Our target was to correlate the findings with a disease's course or a sequalae risk and assess their clinical usefulness.

View Article and Find Full Text PDF

Neurological autoimmune diseases have various origins and pathogeneses. Specific antibodies are associated with paraneoplastic syndromes, other infectious agents, or inherited disorders. We aim to evaluate the relation between the autoantibodies, the chosen symptoms, demographic characteristics, and infection history.

View Article and Find Full Text PDF

The study aimed to analyse the clinical course of COVID-19 in 300 infants, selected from 1283 children diagnosed with COVID-19 between March and December 2020, registered in the SARSTerPED multicenter database. Most of the infants were registered in October and November 2020. 44% of the group were girls, and 56% were boys.

View Article and Find Full Text PDF

COVID-19 pandemic is the biggest epidemiologic problem of the 21st century. A severe course of SARS-CoV-2 infection in children is rare. Sometimes, especially in patients with chronic disease, COVID-19 may be insidious and life-threatening.

View Article and Find Full Text PDF

Children with COVID-19 develop moderate symptoms in most cases. Thus, a proportion of children requires hospital admission. The study aimed to assess the history, clinical and laboratory parameters in children with COVID-19 concerning the severity of respiratory symptoms.

View Article and Find Full Text PDF

Background: Noninvasive diagnostics of nonalcoholic fatty liver disease (NAFLD), the most common cause of liver dysfunction in children, are based on imaging, biochemical tests and their compilation. The study aimed to evaluate the serological biomarkers of steatosis, inflammation and liver fibrosis to assess the risk of NAFLD in children.

Methods: A total of 73 children were included in the prospective study; 50 of them were diagnosed with NAFLD based on ultrasound, and 23 formed a control group.

View Article and Find Full Text PDF

This prospective multicenter cohort study aimed to analyze the epidemiological and clinical characteristics of coronavirus disease 2019 (COVID-19) in children. The study, based on the pediatric part of the Polish SARSTer register, included 1283 children (0 to 18 years) who were diagnosed with COVID-19 between 1 March 2020 and 31 December 2020. Household contact was reported in 56% of cases, more frequently in younger children.

View Article and Find Full Text PDF

Background: Although COVID-19 is associated with a mild course in children, a certain proportion requires admission to hospital due to SARS-CoV-2 infection and coexisting diseases. The prospective multicenter study aimed to analyze clinical factors influencing the length of the hospital stay (LoHS) in children with COVID-19.

Methods: The study included 1283 children from 14 paediatric infectious diseases departments with diagnosed SARS-CoV-2 infection.

View Article and Find Full Text PDF

Despite the enormous advances in knowledge about the SARS-CoV-2 infection, the optimal treatment for COVID-19 is still not well defined. The use of convalescent plasma seems to be a promising method of treatment but requires further evaluation. Although it is usually mild, in children with underlying chronic diseases, the course of SARS-CoV-2 infection may be very severe.

View Article and Find Full Text PDF

Introduction: Children account for a relatively small proportion of laboratory-confirmed SARS-CoV-2 infections. In children, COVID-19 usually has a relatively mild course. However, in rare cases, severe disorders can be observed, and clinical manifestations may differ from adults.

View Article and Find Full Text PDF

Introduction: The global eradication of smallpox and abandonment of mandatory smallpox vaccination has led to an increased proportion of the population who are immunologically naïve to infections caused by (OPV).

Aim: To present the different courses of OPV infection in children and to highlight the diagnostic difficulties in their differentiation from the other inflammatory processes.

Material And Methods: We retrospectively evaluated the medical documentation of 5 children with OPV infection.

View Article and Find Full Text PDF

Aim Of The Study: Assessment of liver fibrosis as a predictive factor of liver-related mortality in children with nonalcoholic fatty liver disease (NAFLD) is crucial. This study aims to estimate the risk of fibrosis using noninvasive markers.

Material And Methods: The study group of 49 children with NAFLD (age range 3-16, mean 10.

View Article and Find Full Text PDF