Ewelina Truszkowska

Serratia species are Gram-negative pathogens responsible for a wide range of nosocomial infections. This multicenter nationwide retrospective study aimed to describe the epidemiology, clinical characteristics, antimicrobial susceptibility, and outcomes of Serratia infections in pediatric oncology patients and hematopoietic stem cell transplantation (HSCT) recipients in Poland between 2012 and 2023. A total of 36 Serratia infection episodes were identified in patients under 20 years of age, including 30 cases (83.3%) in the oncological (OHD) group and six (16.7%) among HSCT recipients. The median age was 4.30 years. The most common underlying diseases were acute lymphoblastic leukemia (36.1%) and central nervous system tumors (16.7%). Bloodstream infections predominated in OHD patients (33.3%), whereas urinary tract infections were most frequent in HSCT recipients (83.3%). S. marcescens was the most commonly isolated species. More than half of isolates (53.3%) showed antimicrobial resistance, with extended-spectrum β-lactamase (ESBL)-producing strains in 26.7% and AmpC β-lactamase-producing strains in 13.3%. Multidrug resistance occurred in 30%. Treatment most often included amikacin, piperacillin/tazobactam, and carbapenems. Five deaths occurred in the OHD group and one in the HSCT group, none directly related to Serratia infection. Although uncommon, Serratia infections remain clinically relevant due to their high antimicrobial resistance, underscoring the need for antimicrobial stewardship.

Background: Due to its relatively low incidence in developed countries, tuberculosis (TB) is rarely considered in differential diagnosis, even among immunocompromised patients. However, with shifting epidemiological patterns, the threat is underestimated. The aim of this study was to describe epidemiology, clinical characteristics, treatment, and outcome of TB in pediatric patients with malignancy and hematopoietic stem cell transplant (HSCT) recipients in Poland. Methods: Five cases of TB were reported from all Polish pediatric hematology, oncology, and transplant centers among patients diagnosed with malignancies or those who underwent HSCT over the period from 2012 to 2023. The infections were categorized into two groups: the malignancy group ( n = 1; 20%) and the HSCT group ( n = 4; 80%). Results: Within the malignancy subgroup, a single case of TB occurred in a female patient aged 1.9 years, who was treated for relapse of B‐cell precursor acute lymphoblastic leukemia (BCP ALL). She developed extrapulmonary TB with lymph node involvement. In the HSCT subgroup, four TB cases were identified in three girls and one boy, with a median age of 0.7 years. All patients had undergone HSCT due to primary immunodeficiencies. The BCP ALL patient was treated with rifampicin and isoniazid. Among the HSCT patients, two received combination therapy with rifampicin, isoniazid, ethambutol, and streptomycin. One patient was treated with rifampicin and isoniazid, and another patient received rifampicin monotherapy. Two children died: BCP ALL patient due to disease progression and transplanted patient because of TB progression. Conclusions: TB should be considered in the differential diagnosis of immunocompromised patients.

Fibroblastic tumors are a heterogeneous group of soft tissue neoplasms. The treatment of these tumors has always been challenging, given their rarity and heterogeneity. The management was based on surgical excision, and chemotherapy was added in advanced metastatic disease. The rapid development of molecular and genetic diagnostics allowed further understanding of the complexity of fibroblastic tumors and the use of targeted therapies, especially kinase inhibitors (KI). Thanks to them, crippling procedures can be omitted, and the subsequent successful treatment lines are possible. However, many questions are still related to KI and its place in treatment protocols. Researchers debate whether KI can replace chemotherapy in the first line of treatment. The need for recommendations switches the decision to physicians and parents. In this paper, we focus on the benefits and problems of KI in fibrosarcoma treatment in the pediatric population. Keywords: fibrosarcoma NRTK inhibitors infantile fibrosarcoma targeted treatment

< p > < /p > Keywords: acute myeloid leukemia hyperleukocytosis leukostasis