Current Organizations / Institutes

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Dorota Kozielewicz has a total of 113 co-authors. Here are the top co-authors by number of shared publications:


Latest Publications

  • Open Access

    Potential Drug Interactions in Psychiatric Patients Undergoing Pangenotypic Therapy for Hepatitis C Virus Infection

    by Dorota Dybowska, Małgorzata Pawłowska, Dorota Kozielewicz

    Over the past decade, significant progress has been made in the treatment of chronic hepatitis C virus (HCV) infection. The introduction of direct-acting antivirals (DAAs) has revolutionized the treatment of HCV infection, offering nearly 100% efficacy. Furthermore, additional therapeutic regimens with pangenotypic efficacy have been registered. These drugs are also characterized by a few adverse events and good treatment tolerance. As DAA therapy is now accessible to virtually all patients, including those with multimorbidity who often take multiple medications, drug interactions (DDIs) have become a significant clinical challenge. One of the groups of patients who are frequently infected with HCV is those with mental disorders. Due to frequently overlapping metabolic pathways, DDIs can occur, affecting the effectiveness of both psychiatric and antiviral therapy. Knowledge of these interactions is crucial in these cases and influences patient management. This paper discusses the most significant interactions between pangenotypic DAA regimens and psychotropic medications.

  • Open Access

    Differences in the Clinical Course of COVID-19 in Patients Hospitalized in the 2023/2024 and 2024/2025 Seasons

    by Robert Flisiak, Dorota Zarębska-Michaluk, Michał Brzdęk, Marta Rorat, Krystyna Dobrowolska, Dorota Kozielewicz, Magdalena Stankiewicz, Anna Moniuszko-Malinowska, Magdalena Rogalska, Łukasz Supronowicz, et al.

    Background/Objectives: The aim of this analysis of data from the multi-year nationwide SARSTer program in Poland was to compare the clinical presentation and course of COVID-19 in the last two infectious seasons. Methods: Clinical data from 719 consecutive patients hospitalized between April 2023 and March 2024 were compared with data from 360 patients hospitalized between 1 April 2024 and 31 March 2025. Results: In the 2023/2024 season, hospitalizations due to COVID-19 occurred primarily between September and January, and in the 2024/2025 season, the majority of hospitalizations occurred between July and November. In the 2024/2025 season, we documented a change in the age structure, with an increasing predominance of hospitalized patients over 70 years of age (68% vs. 60% in 2023/2024), a milder disease manifestation, reflected in a significantly lower percentage of patients with pulmonary lesions (19% vs. 24%), an improvement in the clinical course of the disease, reflected in a halving of the number of hospitalizations, a significantly higher percentage of patients with clinical improvement in subsequent weeks of hospitalization, including those discharged from the hospital within the first week (39% vs. 30%), and a significantly lower mortality rate (4.7% vs. 7.9%), especially among patients over 70 years of age (5.4% vs. 10.4%). This indicates that the trend of a milder disease course initiated by the emergence of the Omicron variant continues. Conclusions: In conclusion, our findings provide real-world clinical evidence of the evolution of the COVID-19 situation in the post-pandemic era.


  • Open Access

    Management of SARS-CoV-2 Infection-Clinical Practice Guidelines of the Polish Association of Epidemiologists and Infectiologists, for 2025

    by Robert Flisiak, Jerzy Jaroszewicz, Dorota Kozielewicz, Ernest Kuchar, Miłosz Parczewski, Małgorzata Pawłowska, Anna Piekarska, Piotr Rzymski, Krzysztof Simon, Krzysztof Tomasiewicz, et al.

    The first Polish recommendations for the management of COVID-19 were published by the Polish Society of Epidemiologists and Infectiologists (PTEiLChZ) on 31 March 2020, and the last three years ago. The emergence of new SARS-CoV-2 variants, a different course of the disease, as well as new knowledge about therapies and vaccines, requires updating diagnostic, therapeutic, and prophylactic guidelines. Despite the reduction in the threat associated with COVID-19, there is a risk of another epidemic caused by coronaviruses, which was an additional reason for developing a new version of the guidelines. In preparing these recommendations, the Delphi method was used, reaching a consensus after three survey cycles. Compared to the 2022 version, the names of the individual stages of the disease have been changed, adapting them to the realities of clinical practice, and attention was paid to the differences observed in immunosuppressed patients and in children. Some previously recommended drugs have been discontinued, including monoclonal antibodies. In addition, general principles of vaccination were presented, as well as issues related to the post-COVID syndrome.


  • Open Access

    Drug-induced liver injury. Part I: Classification, diagnosis and treatment

    by Dorota M. Kozielewicz, Piotr Stalke, Julita Skrzypek

    Drug-induced liver injury (DILI) is a growing clinical problem. Antibiotics remain the most common cause of DILI in Europe. Their clinical spectrum is very broad, from asymptomatic to acute liver failure. Currently, DILI is categorized as hepatocellular (R ≥ 5), cholestatic (R ≤ 2) or mixed (R =...


  • Open Access

    Hepatitis C Infection Is Not a Cardiovascular Risk Factor in Young Adults

    by Paweł Rajewski, Małgorzata Pawłowska, Dorota Kozielewicz, Dorota Dybowska, Anita Olczak, Jakub Cieściński

    Background: Cardiovascular diseases are one of the leading causes of hospitalization and death in Poland and around the world and are still an ongoing problem for modern medicine. Despite advances in diagnosis and treatment, both conservative and invasive, the prevention of cardiovascular disease directed at reducing risk factors remains a problem. The main classical risk factors for the development of cardiovascular disease in Poland include hypertension, lipid disorders, obesity, diabetes and smoking. A new non-classical risk factor is HCV infection. Most of the studies on the impact of HCV infection on cardiovascular disease involve elderly populations with long-term infections and advanced liver fibrosis. Methods: Hence, we set out to analyze the prevalence of risk factors and cardiovascular disease in a population of young adults under 45 years of age infected with HCV, according to gender, HCV genotype and the duration of infection. The study group consisted of 217 patients of both sexes aged 21 to 45 years (mean age 36 years). Results: No cardiovascular disease was found among the young adults infected with HCV in the study group. The most common risk factor was cigarette smoking, which affected 20.7% of the subjects, followed by hypertension (12%) and diabetes mellitus (5.5%); the prevalence was lower than in the general population. Most of the patients were characterized as overweight, with a mean BMI of 26.39 kg/m2. The mean values of other metabolic parameters—total cholesterol, LDL, HDL, uric acid and glucose—were within the population norm. The mean value of CRP was 1.43, which may indicate a moderate cardiovascular risk. Conclusions: Based on the conducted research, it was found that HCV infection in young individuals was not a risk factor for cardiovascular diseases, and the prevalence of risk factors was similar to that in the general population. The effect of HCV on the increase in C-reactive protein requires further study. The early detection of HCV infection and treatment can be considered as a prevention of cardiovascular disease.


  • Open Access

    Association between Liver Damage and Disease Progression Markers with Mortality Risk and Mechanical Ventilation in Hospitalized COVID-19 Patients: A Nationwide Retrospective SARSTer Study

    by Karol Żmudka, Jerzy Jaroszewicz, Dorota Zarębska-Michaluk, Magdalena Rogalska, Piotr Czupryna, Marta Rorat, Dorota Kozielewicz, Jadwiga Maciukajć, Sławomir Kiciak, Magdalena Krępa, et al.

    (1) Background: Liver damage is an important component of acute COVID-19, and the advancement of preexisting liver disease is associated with a worse prognosis; (2) Methods: A nationwide retrospective study including 7444 patients aimed to evaluate levels of selected markers of liver damage and disease advancement and their association with mortality and mechanical ventilation (MV); (3) Results: Elevation of the following markers in multivariate models were associated with increased odds of mortality: Alanine transaminase (ALT), aspartate transaminase (AST), gamma-glutamyltransferase (GGT), lactate dehydrogenase (LDH), fibrosis-4 score (FIB-4), AST-to-platelet ratio index (APRI), and decreased levels of platelet count (PLT). Elevated levels of AST, LDH, APRI, FIB-4, and the AST/ALT ratio and decreased levels of PLT were associated with increased odds of MV in multivariate models. The best predictive accuracy against mortality was achieved with FIB-4 with AUC = 0.733 (95% CI, 0.718–0.749) at the optimal cut-off point of 2.764, while against MV was achieved with LDH with AUC = 0.753 (95% CI, 0.727–0.778) at the optimal cut-off point of 449.5 IU/L. (4) Conclusions: Our study confirms that the advancement of liver damage contributes to a worse prognosis in COVID-19 patients. Markers for liver damage and the advancement of liver disease can provide predictive value in clinical practice among COVID-19 patients.


  • Open Access

    Change in the Clinical Picture of Hospitalized Patients with COVID-19 between the Early and Late Period of Dominance of the Omicron SARS-CoV-2 Variant

    by Robert Flisiak, Dorota Zarębska-Michaluk, Krystyna Dobrowolska, Marta Rorat, Magdalena Rogalska, Justyna Anna Kryńska, Anna Moniuszko-Malinowska, Piotr Czupryna, Dorota Kozielewicz, Jerzy Jaroszewicz, et al.

    This study aimed to compare the clinical picture of COVID-19 in the initial and later period of Omicron dominance and to identify populations still at risk. A retrospective comparison of the clinical data of 965 patients hospitalized during the early period of Omicron’s dominance (EO, January–June 2022) with 897 patients from a later period (LO, July 2022–April 2023) from the SARSTer database was performed. Patients hospitalized during LO, compared to EO, were older, had a better clinical condition on admission, had a lower need for oxygen and mechanical ventilation, had less frequent lung involvement in imaging, and showed much faster clinical improvement. Moreover, the overall mortality during EO was 14%, higher than that in LO—9%. Despite the milder course of the disease, mortality exceeding 15% was similar in both groups among patients with lung involvement. The accumulation of risk factors such as an age of 60+, comorbidities, lung involvement, and oxygen saturation <90% resulted in a constant need for oxygen in 98% of patients, an 8% risk of mechanical ventilation, and a 30% mortality rate in the LO period. Multiple logistic regression revealed lower odds of death during the LO phase. Despite the milder course of infections caused by the currently dominant subvariants, COVID-19 prophylaxis is necessary in people over 60 years of age, especially those with comorbidities, and in the case of pneumonia and respiratory failure.


  • Open Access

    Retrospective Analysis of the Effectiveness of Remdesivir in COVID-19 Treatment during Periods Dominated by Delta and Omicron SARS-CoV-2 Variants in Clinical Settings

    by Krystyna Dobrowolska, Dorota Zarębska-Michaluk, Michał Brzdęk, Piotr Rzymski, Magdalena Rogalska, Anna Moniuszko-Malinowska, Dorota Kozielewicz, Marcin Hawro, Marta Rorat, Katarzyna Sikorska, et al.

    Continuous evaluation of real-world treatment effectiveness of COVID-19 medicines is required due to the ongoing evolution of SARS-CoV-2 and the possible emergence of resistance. Therefore, this study aimed to analyze, in a retrospective manner, the outcomes in patients hospitalized with COVID-19 during the pandemic waves dominated by Delta and Omicron variants and treated with remdesivir (RDV) (n = 762) in comparison to a demographically and clinically matched group not treated with any antivirals (n = 1060). A logistic regression analysis revealed that RDV treatment was associated with a significantly lower risk of death during both Delta wave (OR = 0.42, 95%CI: 0.29–0.60; p < 0.0001) and Omicron-dominated period (OR = 0.56, 95%CI: 0.35–0.92; p = 0.02). Moreover, RDV-treated groups were characterized by a lower percentage of patients requiring mechanical ventilation, but the difference was not statistically significant. This study is the first real-world evidence that RDV remains effective during the dominance of more pathogenic SARS-CoV-2 variants and those that cause a milder course of the disease, and continues to be an essential element of COVID-19 therapy.


  • Open Access

    Variability in the Clinical Course of COVID-19 in a Retrospective Analysis of a Large Real-World Database

    by Robert Flisiak, Piotr Rzymski, Dorota Zarębska-Michaluk, Przemysław Ciechanowski, Krystyna Dobrowolska, Magdalena Rogalska, Jerzy Jaroszewicz, Anna Szymanek-Pasternak, Marta Rorat, Dorota Kozielewicz, et al.

    The COVID-19 pandemic proceeds in waves, with variable characteristics of the clinical picture resulting from the evolution of the SARS-CoV-2 virus. This study aimed to compare the epidemiological characteristics, symptomatology, and outcomes of the disease in patients hospitalized for COVID-19 during periods of different variants dominance. Comparing the periods of dominance of variants preceding the Delta variant, the Delta period was characterized by a higher share of hospitalized females, less frequent comorbidities among patients, and a different age distribution. The lowest need for oxygen therapy and mechanical ventilation was observed under Omicron dominance. The triad of classic COVID-19 symptoms, cough, fever, dyspnoea, and fatigue, were most prevalent during the Delta period, and significantly less common under the Omicron dominance. During the Omicron period, nearly twice as many patients as in the previous periods could be discharged from the hospital within 7 days; the overall 28-day mortality was significantly lower compared to that of the Delta period. It also did not differ between periods that were dominated by the BA.1 and BA.2 subvariants. The study indicates that the Omicron SARS-CoV-2 variant that dominated between January and June 2022 caused a disease which resembled the common cold, and was caused by seasonal alpha and beta-coronaviruses with a low pathogenicity for humans. However, one should note that this effect may not only have been related to biological features of the Omicron lineage, but may additionally have been driven by the increased levels of immunization through natural infections and vaccinations, for which we could not account for due to a lack of sufficient data.


  • Open Access

    The Course of COVID-19 in Patients with Systemic Autoimmune Rheumatic Diseases

    by Marta Rorat, Dorota Zarębska-Michaluk, Justyna Kowalska, Krzysztof Kujawa, Magdalena Rogalska, Dorota Kozielewicz, Beata Lorenc, Katarzyna Sikorska, Piotr Czupryna, Beata Bolewska, et al.

    Patients with systemic autoimmune rheumatic disease (SARD) have increased susceptibility to viral infections, including SARS-CoV-2. The aim of this study was to analyse the SARD patient population with COVID-19 (coronavirus disease 2019) in terms of baseline characteristics, severity, course and outcomes of the disease compared with the non-SARD group, and to identify factors associated with prognosis, including remdesivir therapy efficacy. Retrospective study comprised 8220 COVID-19 cases from the SARSTer database, including 185 with SARD. Length of hospitalisation, duration of oxygen therapy, mortality and the need for HFNO (high-flow nasal oxygen) and/or NIV (noninvasive ventilation) were significantly higher in the SARD versus non-SARD group. There was no difference in clinical features on admission to hospital. Patients with SARD were older and more likely to have cardiovascular, pulmonary and chronic kidney diseases. Age, the presence of cardiovascular disease, more severe conditions on admission and higher inflammatory marker values were found to be risk factors for death in the SARD group. In patients with SARD treated with remdesivir, there was a trend towards improved mortality but without statistical significance. Length of hospitalisation, 28-day mortality and the need for HFNO and/or NIV were higher in the SARD group. These patients often had other chronic diseases and were older.