Idiopathic nephrotic syndrome (INS) is a chronic glomerular disease in children, characterized by severe proteinuria, hypoalbuminemia, and/or presence of edema and hyperlipidemia. The pathogenesis, however, has not been yet established. The clinical course of the disease is characterized by frequent relapses. Interleukin-15 (IL-15) is a pro-inflammatory cytokine, that apart from its involvement in the immune system, was found to be playing a vital role in various cells’ functioning, including renal tissue. It is desirable to look for new predictors of INS. Our study aimed to evaluate IL-15 as a potential marker in the early diagnosis of the disease. The cohort participating in the study consisted of patients hospitalized in Clinical Hospital No. 1 in Zabrze, from December 2019 to December 2021, including study group with INS (n = 30) and control group (n = 44). Results: The concentration of IL-15 in both serum and urine was significantly elevated in patients with INS, compared to healthy controls. The cytokine might serve as a marker of the disease, however, further research on larger study groups is needed.

Chronic kidney disease (CKD) is a progressive condition which still leads to significant morbidity and mortality among patients at all ages. Its proper management should be focused on slowing down the disease sequelae, as well as establishing an early diagnosis and treatment of its complications. Eotaxin is a potent, selective eosinophil chemoattractant, which is reported to have an impact on various kidney diseases. Nevertheless, data regarding the potential correlation between eotaxin and CKD in a pediatric population is still scarce. This study aims to assess the concentration of eotaxin in children with CKD and evaluate potential correlations with selected biochemical markers and disease occurrence. Both serum and urine eotaxin concentrations were markedly higher in children with CKD compared to healthy controls. Moreover, Receiver Operating Characteristic (ROC) curves have shown that serum eotaxin and urine eotaxin levels demonstrated high sensitivity and high specificity for the allocation of patients to the study and control groups. The authors advanced a thesis that eotaxin might serve as a marker of CKD occurrence in a pediatric population. Such a research design is innovative, since it has not been analyzed in the literature yet. However, further studies are required.

Pathogenic variants in the Wilms’ tumor suppressor gene 1 (WT1 gene) can lead to serious disorders within the kidney and urogenital system, including chronic kidney disease. There is still much uncertainty regarding the optimal management of diseases caused by WT1 dysfunction, posing a challenge for physicians caring for these patients. The aim of our study is to present experiences related to the course and treatment of patients with confirmed WT1 pathogenic variants. Data from seven patients (five girls, two boys), who were at the age of 4.8 ± 5.1 years (0.3–14 years) at their first admission and were treated between 1997–2022, were analyzed. The analysis included each patient’s age at the day of diagnosis, anthropometric measurements, comorbidities, and laboratory and genetic test results, as well as their treatment, oncological procedures, and performed surgeries. Wilms’ tumor was the first manifestation of the disease in three patients. Arterial hypertension was diagnosed in three patients, and anemia in four. Treatment of patients with nephrotic syndrome included glucocorticosteroid therapy (GCS), calcineurin inhibitors (CNIs), and mycophenolate mofetil (MMF). Nephrectomy was performed in five children, while kidney transplantation was carried out in two patients. An interdisciplinary approach to WT1 gene pathogenic variants, including early diagnosis, individualization, regular monitoring of treatment, and oncological vigilance, is crucial for improving prognosis and ensuring proper care for patients with nephrological manifestations of WT1 gene region disorders. Furthermore, for a comprehensive understanding of the scope of this disease and the development of effective therapy methods, continued research on the clinical manifestations of WT1 pathogenic variants is essential.

Nesfatin-1 is a recently discovered protein with a pleiotropic function on various organs, including kidneys. This molecule presents antiapoptotic, antihyperglycemic, antioxidative, and anorectic features. Available data regarding the role of nesfatin-1 in kidney function and diseases focuses on chronic kidney disease, acute kidney injury, blood pressure, and renal cell carcinoma. Various studies have shown that the levels of nesfatin-1 were increased in patients with diabetic kidney disease (DKD); therefore, it was suggested that nesfatin-1 might act as an early DKD marker. Furthermore, the potential protective function of nesfatin-1 against inflammation, oxidative stress, fibrosis, and apoptosis in kidney tissues was described in several studies. Alternatively, as reported in the literature, a positive correlation between blood pressure elevation and nesfatin-1 levels was noted. Moreover, nesfatin-1 might exert influence on renal cell carcinoma progression and invasion of cancerous cells. Nesfatin-1 shows considerable potential for acting as a prognostic marker or a defensive factor for kidney diseases; however, further investigation, especially in the pediatric population, is still required. Graphical abstract

Cystic kidney disease is characterized by progressive structural remodeling of renal parenchyma and altered cellular signaling. Inflammatory mediators may contribute to disease biology; however, data on interleukin-15 (IL-15) in pediatric cystic kidney disorders remain limited. The aim of this study was to assess serum and urinary IL-15 concentrations in children with cystic kidney disease and to evaluate their association with renal function. Methods: This study included 47 children with cystic kidney disease and 41 controls without renal cystic disease or other systemic, inflammatory, or immunological disorders. Serum and urinary IL-15 concentrations were measured using an enzyme-linked immunosorbent assay (ELISA). Renal function was assessed using the estimated glomerular filtration rate (eGFR). Statistical analyses included non-parametric comparisons, logistic regression, and receiver operating characteristic (ROC) curve analysis. Results: Children with cystic kidney disease demonstrated significantly elevated serum and urinary IL-15 concentrations compared with controls. IL-15 levels were not associated with eGFR and did not differ between cystic disease subtypes. In logistic regression analysis, IL-15 remained significantly associated with disease status. ROC analysis suggested high diagnostic ability of serum and urinary IL-15. Conclusions: IL-15 concentrations are increased in children with cystic kidney disease independently of current renal function. These findings suggest that IL-15 may reflect early inflammatory or epithelial signaling rather than established functional impairment.