Chronic kidney disease (CKD) is the fifth globally socially significant chronic non–communicable disease recognized by WHO. The prevalence of CKD in the world ranges from 10 to 20 % and outstrips the prevalence of diabetes mellitus and cardiovascular diseases (850, 600, and 560 million people, respectively). By 2040, CKD will become the 5th cause of premature mortality, ahead of cancer and diabetes mellitus. In Russia, the prevalence of CKD in risk groups (hypertension, chronic heart failure, and diabetes mellitus) is at least 16 % of the country's population. CKD significantly increases the medical, social, and financial burden on the state budget, a significant part of which is spent on saving the lives of patients who have survived to the end stage renal disease, such as kidney replacement therapy (dialysis, kidney transplantation) and treatment of comorbid conditions. CKD makes a huge contribution to premature mortality. Most patients die from cardiovascular complications (strokes, heart attacks, heart failure) before the development of the terminal stage of the disease. Early detection of the disease will improve the ability to work and enhance the quality of life, as well as increase its duration. Special attention should be paid to risk groups, primarily patients with cardiovascular diseases and diabetes mellitus. The current management strategy for CKD patients is prevention and screening for early manifestations of CKD (decreased glomerular filtration rate and albuminuria), followed by the use of triple cardio–reno-protective therapy (RAAS inhibitors, glyphlozines, synthetic mineralocorticoid receptor blockers), which can slow the progression to the terminal stage of the disease and reduce mortality from cardiovascular complications. Preserving and prolonging the lives of CKD patients requires appropriate government organizational measures – in essence, changing the existing healthcare model focused on the terminal stages of the disease to a model aimed at prevention, early detection, and slowing the progression of CKD

Chronic kidney disease (CKD) is widespread and occurs in 10-13 % of the world's population. For example, in the United States alone, according to the latest data, 37 million adult patients have been diagnosed with the disease. With this pathology, the physiological and biological mechanisms of homeostasis are affected (electrolyte and pH balance, regulation of blood pressure and the endocrine system, elimination of toxins, and metabolic disorders). The disease is irreversible, asymptomatic at the initial stages, gradually progresses and homeostasis disorders become clinically significant. Conservative nephroprotective therapy is performed at the initial stages. In the later stages, there is a need for replacement therapy (hemodialysis, peritoneal dialysis and kidney transplantation). The goal of conservative treatment of CKD is to slow the progression of renal pathology, as well as to correct complications from other organs and body systems (metabolic conditions, cardiovascular disorders, anemia, etc.). Unfortunately, the algorithms developed today for the treatment of CKD do not solve all the issues and force us to look for new, additional approaches to correcting certain pathological processes in CKD. It is from a pharmacotherapeutic perspective that melatonin (MT) has attracted attention in recent years, showing its ability to limit most manifestations of CKD. The purpose of this review is to summarize information about the potential use of MT in CKD, taking into account its positive effect on the cardiovascular system, diabetes, homeostasis, and a number of other conditions associated with renal pathology.

The pathogenetic approach to metaphylaxis of urolithiasis is a widespread, socially significant healthcare issue due to the increasing incidence and, particularly, its recurrent nature, despite advances in pharmacotherapy and the application of lithotripsy. Pathological crystal genesis is viewed as a consequence of exceeding the solubility threshold of various urinary mineral components on one hand, and as a result of post-translational defects in the main proteome of urine formation – uromodulin (UMOD), which demonstrates a sanogenetic system in healthy individuals for maintaining biophysical homeostasis stability: the colloidal properties of urine. However, in addition to this, UMOD, by binding mannose-dependent pili of infectious agents, blocks bacterial contact with urothelial cells, given that urinary tract infection is a known factor in urolithiasis. By modeling the urine of healthy individuals through co-incubation with E. coli bacteria, a decrease in the concentration of polymerized uromodulin in urine has been demonstrated as a factor increasing the risk of calcium oxalate crystal formation.

Chronic kidney disease (CKD) is an independent risk factor for cardiovascular disease and is a global burden with high economic costs for health systems. All stages of CKD are associated with an increased risk of cardiovascular events, premature mortality, and/or decreased quality of life. CKD is usually asymptomatic until the late stages, and accurate data on its prevalence are not available, including in the Russian Federation. In the medical literature, there are isolated works devoted to the study of the prevalence of CKD in patients with metabolic syndrome in a large population of patients, including those in need of various endovascular interventions that pose an additional risk of CKD progression. THE AIM: to study the prevalence of individual components of cardiorenometabolic syndrome depending on the presence of CKD in a sample of patients with cardiovascular disease planning endovascular intervention. PATIENT AND METHODS. The study included 9731 patients over 18 years of age, planning endovascular intervention. All patients were examined in accordance with Russian clinical guidelines. CKD C3a-C4 was diagnosed in 4378 patients. RESULTS. Patients with CKD were more likely to have diabetes mellitus, hypertension, atrial fibrillation and/or flutter, and CHF. Metabolic characteristics included higher body mass index, cholesterol, and CRP levels. CONCLUSION. Effective interdisciplinary collaboration between physicians of various specialties appears to be a key component of the management strategy for this patient population, with the aim of improving diagnostic and treatment algorithms and slowing the progression of cardiovascular disease and CKD.

BACKGROUND. Thyroid dysfunction is a common complication in patients with end-stage renal disease (ESRD) receiving maintenance hemodialysis. However, the role of the autoimmune component in these disorders remains insufficiently studied.
THE AIM: to study the features of thyroid dysfunction and the role of the autoimmune component in its development in patients with ESRD on maintenance hemodialysis.
PATIENTS AND METHODS. The study included 134 patients with ESRD on maintenance hemodialysis. All participants underwent comprehensive clinical and laboratory evaluation, including measurement of thyroid-stimulating hormone (TSH), free T3 and T4, anti-thyroid peroxidase antibodies (anti-TPO), as well as basic biochemical and hematological parameters. Statistical analysis was performed using standard comparative methods.
RESULTS. Hypothyroidism was diagnosed in 30.6 % of patients; however, elevated anti-TPO levels were found only in a quarter of them. In patients with hypothyroidism, the median anti-TPO level was significantly higher than in the euthyroid group (1.50 [0.70; 7.50] vs. 0.80 [0.30; 3.70] IU/mL, p = 0.021). Sex, age, body mass index, and renal disease etiology did not influence the development of hypothyroidism or elevated anti-TPO.
CONCLUSION. Among patients with ESRD on hemodialysis, hypothyroidism is common, while the autoimmune mechanism is present only in a subset of cases. Thyroid dysfunction is multifactorial and should be taken into account in diagnosis and management.

THE AIM: to study the genetic aspects of metabolically healthy and metabolically complicated obesity in Uzbek women - the prevalence of polymorphisms of the PPARGC1A Gly482Ser gene, as well as to assess its relationship with the functional state of the kidneys, clinical, metabolic, hormonal parameters.
PATIENTS AND METHODS: The study involved 224 obese Uzbek women, who were divided into 2 groups: group 1 consisted of 133 women with metabolically complicated obesity, and group 2 consisted of 91 women with metabolically healthy obesity. The control group consisted of 45 healthy women with representative data. In the observation groups, anthropometric parameters, blood pressure, and body composition were determined - the amount of fluid in the body, the visceral obesity index, fat mass, the proportion of active cell mass, the musculoskeletal mass index, and the body water content were studied. We also studied biochemical analyses and the lipid spectrum, the levels of leptin, insulin, cystatin C and uromodulin, IL-6, alpha-TNF, CRP in blood serum, gradations of microalbuminuria in urine, calculated GFR for cystatin C and creatinine, and compared the obtained indicators. The results of all the above studies were compared with the frequency of occurrence of Gly and Ser allele genotypes, GlyGly, GlySer, and SerSer genotypes of the Gly482Ser polymorphism of the PPARGC1A gene in all groups.
RESULTS: When studying the functional state of the kidneys, depending on the occurrence of genotypes of the Gly482Ser polymorphism of the PPARGC1A gene in the MOO group, the following was found. Serum creatinine and cystatin C levels in carriers of the SerSer genotype in the MOO group were significantly higher than in carriers of the GlySer and GlyGly genotypes, as well as in carriers of the SerSer genotype in the comparison groups; the highest MAU and the lowest GFR were found, calculated on the basis of both uromodulin and creatinine and cystatin. When studying the distribution of genotypes depending on the gradation of MAU, the following was revealed. The prevalence of the SerSer genotype in the MOO group is consistent with an increase in the MAU graduation rate. On the contrary, the frequency of occurrence of the GlyGly genotype was higher in patients in the group with optimal MAU. In the MZO group, the SerSer genotype was more common with a slightly increased MAU. On the contrary, the prevalence of the GlyGly genotype decreased with an increase in the MAU graduation rate.
CONCLUSION. Thus, when analyzing the frequency of alleles and genotypes of the Gly482Ser polymorphism of the PPARGC1A gene, depending on the degree of obesity in the groups, the following was revealed. The Ser allele has an aggressive character in relation to an increase in BMI and the development of MOO, and the Gly allele of this polymorphism has demonstrated a protective character in relation to the development of MOO. The SerSer genotype was significantly more common in the MOO group with grade III obesity, while the GlyGly genotype was significantly more common in the control group. Consequently, in the MOO group, the prevalence of the Ser allele and the SerSer genotype of the Gly482Ser polymorphism of the PPARGC1A gene corresponded to an increase in BMI. In the MHO group, the prevalence of the Ser allele and the SerSer genotype of this polymorphism increased in accordance with an increase in BMI. In this group, the prevalence of the Gly allele and the GlyGly genotype decreased, as opposed to an increase in BMI. It was also found that the SerSer genotype of the Gly482Ser polymorphism of the PPARGC1A gene has a pathogenetic significance in the deterioration of the functional state of the kidneys in both phenotypes of obesity, while the GlyGly genotype, on the contrary, has a protective effect on the progression of this patholo

BACKGROUND. The lack of reliable methods for predicting the development of treatment-refractory membranous nephropathy (MNP) with nephrotic syndrome (NS) is due to a lack of understanding of the mechanisms of NS resistance to treatment.
THE AIM: to study the features of the cytokine status in patients with MNP and their significance in the formation and prediction of refractory NS.
PATIENTS AND METHODS. The study was prospective and included a cohort of patients with MPN who were admitted to the nephrology department with active NS and were subsequently followed up for 24 months in the nephrologist's office at the polyclinic. The study endpoint was the completion of the 24-month follow-up period, during which the study group was divided into two subgroups based on their response to treatment: a subgroup of patients with treatment-responsive NS and a subgroup of patients with treatment-refractory NS. At the beginning of treatment and after 24 months, blood and urine samples were collected to determine the levels of cytokines IL-2, IL-4, IL-8, IL-10, and IL-17A, which were stored at -70°C until analysis. The levels of cytokines were determined simultaneously using enzyme-linked immunosorbent assay at the end of treatment.
RESULTS. The study included 136 patients with MNP: 98 patients with the debut of NS, 25 with persistent NS, and 13 with frequent NS relapses. After 24 months of follow-up, 78 patients were found to have NS remission. 58 patients were refractory to treatment. In patients with refractory NS, blood and urine samples showed increased baseline levels of pro-inflammatory cytokines IL-8 and IL-17A and decreased levels of IL-10 compared to those in patients who achieved disease remission.
CONCLUSION. According to the results of the study, the initial normalized by creatinine levels of IL-8 and IL-17A in the urine can be used as biomarkers for early prediction of refractory NS in MPN

BACKGROUND. Acute kidney injury (AKI) and comorbidities including cardiovascular disease, diabetes mellitus (DM), metabolic disorders, and other factors exacerbate the severity of the novel coronavirus infection (COVID-19). We studied 769 patients with COVID-19. In all cases, the novel coronavirus infection was severe and accompanied by organ dysfunction. We assessed the incidence of AKI, risk factors, and mortality in hospitalized patients with severe COVID-19.
THE AIM: to study the risk factors, incidence of AKI, need for renal replacement therapy (RRT), and mortality among patients with complicated COVID-19.
PATIENTS AND METHODS. The study included adult patients transferred to the Vladimirsky Regional Clinical Institute from hospitals in the Moscow Region with severe COVID-19 in 2020–2024. The COVID-19 diagnosis was confirmed using polymerase chain reaction (PCR) testing of nasopharyngeal samples. Patient characteristics and laboratory test results were assessed using an electronic database.
RESULTS. Analysis of the obtained results shows that mortality increased with the progression of lung disease (from 34 % with stage 2 lung disease to 76 % with stage 4) and the need for mechanical ventilation. AKI was observed in almost half of patients (46 %), but the incidence of AKI did not statistically significantly increase with lung disease progression. AKI was most often observed in stage 3 lung disease (52 % of patients). Gender did not statistically significantly affect mortality. Older patients were significantly more likely to die (mean age 56 years among survivors and 64.4 years among deaths). The need for mechanical ventilation was a significant risk factor for death. Thus, the mortality rate among patients without mechanical ventilation was 8.4 %, compared to 91.6 % among those receiving mechanical ventilation. The mortality rate was higher in patients with hypertension (87 %), chronic kidney disease (40.6 %), diabetes (36 %), and among patients receiving RRT (68 %).
CONCLUSION. In addition to the stage of lung disease, factors aggravating the course of COVID- 19 included comorbid cardiovascular diseases, chronic kidney disease and acute kidney injury, metabolic disorders, age, and the need for RRT.

Being one of the key representatives of the group of biologically significant gases, along with nitrogen oxide and carbon monoxide, hydrogen sulfide demonstrates pronounced antioxidant properties, suppressing inflammatory processes and exerting a protective effect on tissues in various diseases.
THE AIM: to study the effect of sodium thiosulfate on filtration and reabsorption processes in rats with acute renal injury (AKI).
MATERIALS AND METHODS: AKI was modeled by a single intramuscular injection of 50% glycerol solution (10 ml/kg). Sodium thiosulfate was administered intraperitoneally at a dose of 0.1 g/kg every other day for three days.
RESULTS: Experimental data show that the use of sodium thiosulfate significantly reduces the negative effects of intoxication caused by the administration of glycerol to animals. After administration of the drug, the damaged structures of the renal epithelium were restored, signs of inflammation and oxidative stress were eliminated, and creatinine and urea levels returned to normal. Our results demonstrate an increase in the levels of sodium and chlorine ions in the blood plasma of animals treated with sodium thiosulfate, which reflects an improvement in kidney condition and restoration of the main transport processes.
CONCLUSION: Thus, sodium thiosulfate, due to its antioxidant properties, neutralizes free radicals and suppresses oxidative stress caused by glycerol, as evidenced by changes in the concentration of urea nitrogen, creatinine in plasma and daily diuresis and restoration of electrolyte balance in plasma and urine in rats treated.

Currently, the leading factors in the development and progression of chronic kidney disease (CKD) are type 2 diabetes mellitus and arterial hypertension, which are often caused by obesity resulting from overeating. The literature clearly shows that a properly selected diet has a beneficial effect not only on blood pressure and carbohydrate metabolism, but also on kidney function. The presence of CKD in most cases assumes comorbidity, and therefore requires the selection of an optimal diet that includes correction of all existing metabolic disorders. Today, there are more than 100 diets known, but it remains unclear which one is best for these patients. Moreover, the effect of major macronutrients on renal function remains controversial and has not been fully studied. The article describes three clinical cases of a low-carbohydrate diet (LCD) with moderate carbohydrate intake and its effect on renal function and metabolic parameters. This dietary option in patients with metabolic disorders, combined with high patient adherence to the diet, led to improved kidney function and carbohydrate, lipid and purine metabolism indicators, weight loss, a reduction in the doses and number of medications used, and in some cases helped to normalise blood pressure.

Familial hypomagnesemia with hypercalciuria and nephrocalcinosis (FHHNC) is a rare autosomal recessive disorder of the renal tubules caused by mutations in the CLDN 16 or CLDN19 genes encoding the proteins claudin-16 and claudin-19. CLDN 16 or CLDN19 play an important role in the cellular transport of magnesium and calcium in the thick ascending limb of the loop of Henle and are responsible for most of the tubular magnesium reabsorption. FHHNC is characterized by hypomagnesemia, hypercalciuria, medullary nephrocalcinosis, and eye involvement, and progresses to chronic renal failure requiring dialysis and kidney transplantation, mainly in young adults. A clinical case of rapidly progressive renal function decline in a patient with mutations in the CLDN19 gene without ocular involvement is demonstrated.

BACKGROUND. Tuberous sclerosis is an orphan systemic disease with an autosomal dominant inheritance characterized by the formation of tumor–like benign nodular hamartomas with lesions of the skin, nervous system, retina, kidneys, heart, and lungs. In 50–70 % of children and adolescents with tuberous sclerosis, the renal phenotype is more often diagnosed in the form of angiomyelitis and kidney parenchymal cysts. The presence of kidney damage complicates the course and prognosis of tuberous sclerosis due to the risk of acute kidney injury and the progression of chronic kidney disease.
OBJECTIVE: To describe familial tuberous sclerosis (ORPHA:805) due to a pathogenic mutation of the TSC2 gene with an autosomal dominant type of inheritance.
PATIENTS AND METHODS. The features of the clinical phenotype and genotype of tuberous sclerosis in a 16–year-old proband girl and her 45-year-old male father are described. Genealogical, clinical, imaging, functional, and molecular genetic research methods have been applied. The molecular genetic research method was performed in the laboratory of molecular pathology of the medical and genetic center of Genomed.
RESULTS. A 16-year–old patient was diagnosed with tuberous sclerosis at an early age in the presence of 2 major criteria (1. rhabdomyoma of the heart prenatally and at birth, 2. cortical tubers of the frontal and parietal regions, foci of calcification in the cerebellum, decreased hypocampus manifested by delayed speech development and epilepsy with atonic and generalized tonic-clonic seizures in infancy and early age). Manifestations of the renal phenotype (increased kidney volume and parenchymal cysts) They were detected at the age of 6 years, liver angiomyolipomas were noted at the age of 8, and kidneys at the age of 16. A molecular genetic study identified a pathogenic mutation of the TSC2 gene in the proband (c.1052AG, p.Lys351Arg). The renal function in proband at the age of 16 years corresponds to stage 2 of chronic kidney disease (GFR 84ml/min/1.73 m2). A similar mutation was detected in Proband's father, who has a normal glomerular filtration rate (134ml/min/1.73 m2), a single kidney cyst, tuberous sclerosis was diagnosed at the age of 45 according to 2 major criteria (3 periarticular fibroids and 3 hypopigmented spots over 5 mm on the skin).
СONCLUSION. The features of the clinical phenotype of familial orphan tuberous sclerosis due to a previously undescribed mutation of the TSC2 gene in a proband girl and father are described.

With long-term renal replacement therapy with hemodialysis, all possible vascular accesses may gradually be lost, including those associated with previous catheterizations. Furthermore, peritoneal dialysis is typically no longer effective in these patients. In such clinical cases, the only viable option is to attempt a tunneled central venous catheter (CVC) for hemodialysis as a life-saving procedure, based on life-saving indications. Such situations may be uncommon, but they do occur quite regularly. The use of transhepatic access as an additional method for central vein recanalization is justified, but only in the absence of other, less risky options. In cases of complete loss of classic vascular accesses following an unsuccessful attempt at transhepatic recanalization of the central veins, a tunneled CVC can be inserted into the right atrium through the created access.