Background: Schimke immuno-osseous dysplasia (SIOD, OMIM 242900) is a rare, autosomal recessive, pleiotropic disease caused by mutations in the SMARCAL1 gene. SIOD is characterized by a triad of symptoms, i.e., progressive kidney disease due to focal segmen- tal glomerulosclerosis (FSGS), spondyloepiphyseal dysplasia and T-cell immunodeficiency. Additionally, heterogeneous neurological symptoms are often observed in the course of the syndrome. Case: The authors describe the case of a 14-year-old girl with SIOD, who presented with recurrent neurological symptoms, such as migraine-like headaches, diplopia and seizures. She was born at 34 weeks of pregnancy with hypotrophy (1280 g) and short stature (44 cm). Nephrotic-range proteinuria, the first symptom of the disease, was detected at the age of 4 and a half years. Significant immunodeficiency was also observed. She was finally diagnosed with Schimke immuno-osseous dysplasia on account of two pat- hogenic variants, c.836T>C (p.F279S) and c.2542G>T (p.E848X) identified in the SMARCAL1 gene. Conclusions: This report describes the clinical features and neuroimaging findings of a patient with SIOD. It also presents a possible correlation between neurological events and the Schimke disease, which should be considered during the diagnostic process.

Hemolytic uremic syndrome (HUS) is defined by the triad of microangiopathic hemolytic anemia, thrombocytopenia, and acute kidney injury (AKI). Atypical HUS (aHUS), distinguished by its etiology, is caused by uncontrolled overactivation of the alternative complement pathway. The correct diagnosis of aHUS is complex and involves various gene mutations. Severe combined immunodeficiency (SCID), characterized by severe T-cell lymphocytopenia and a lack of antigen-specific T-cell and B-cell immune responses, is of seldom occurrence. In 10–15% of pediatric patients, SCID is caused by adenosine deaminase (ADA) deficiency. The authors describe the case of a boy who suffered from both aHUS and ADA-deficient SCID. At the age of 9 months, the patient presented acute kidney injury with anuria and coagulopathy. The diagnosis of aHUS was established on the basis of alternative complement pathway deregulation and disease-associated gene mutations. Further examination revealed immune system failure and, at the age of 13 months, the ADA deficiency was confirmed by genetic tests and the boy was diagnosed with ADA-SCID. ADA SCID has recently been described as a possible triggering factor of aHUS development and progression. However, more research is required in this field. Nevertheless, it is crucial in clinical practice to be aware of these two co-existing life-threatening diseases.

Idiopathic nephrotic syndrome (INS) is a chronic disease affecting children in early childhood. It is characterized by proteinuria, hypoalbuminemia, edema and hyperlipidemia. To date, the diagnosis is usually established at an advanced stage of proteinuria. Therefore, new methods of early INS detection are desired. This study was designed to assess brain-derived neurotrophic factor (BDNF) as a potential marker in the early diagnosis of INS. The study group included patients with a diagnosis of idiopathic nephrotic syndrome (n = 30) hospitalized in Clinical Hospital No. 1 in Zabrze, from December 2019 to December 2021. Our study shows that serum BDNF concentration decreased and urine BDNF concentration increased in a group of patients with INS, compared with healthy controls. Such outcomes might be related to loss of the BDNF contribution in podocyte structure maintenance. Moreover, we anticipate the role of BDNF in urine protein concentration increase, which could be used as a direct predictor of urine protein fluctuations in clinical practice. Moreover, the ROC curve has also shown that serum BDNF and urine BDNF levels might be useful as an INS marker.

Case presentation An 8-year-old Caucasian boy with a complex urinary tract anomaly and chronic kidney disease presented with a mass in the renal pelvis in ultrasound during routine checkup. The urinary tract anomaly was first revealed in the 26th week of pregnancy with bilateral hydronephrosis and possible posterior urethral valve in prenatal ultrasound. The delivery was uncomplicated with a birth weight of 3860 g and an Apgar score of 10. During the neonatal period, a voiding cystourethrography was performed and ruled out a posterior urethral valve as well as vesicoureteral reflux. Dynamic renal scintigraphy showed significant loss of the left kidney function and impaired urinary outflow from the right kidney with * Andrzej Badeński