The high burden of kidney disease, global disparities in kidney care, and poor outcomes of kidney failure bring a concomitant growing burden to persons affected, their families, and carers, and the community at large. Health literacy is the degree to which persons and organizations have or equitably enable individuals to have the ability to find, understand, and use information and services to make informed health-related decisions and actions for themselves and others. Rather than viewing health literacy as a patient deficit, improving health literacy largely rests with health care providers communicating and educating effectively in codesigned partnership with those with kidney disease. For kidney policy makers, health literacy provides the imperative to shift organizations to a culture that places the person at the center of health care. The growing capability of and access to technology provides new opportunities to enhance education and awareness of kidney disease for all stakeholders. Advances in telecommunication, including social media platforms, can be leveraged to enhance persons’ and providers’ education; The World Kidney Day declares 2022 as the year of “Kidney Health for All” to promote global teamwork in advancing strategies in bridging the gap in kidney health education and literacy. Kidney organizations should work toward shifting the patient-deficit health literacy narrative to that of being the responsibility of health care providers and health policy makers. By engaging in and supporting kidney health-centered policy making, community health planning, and health literacy approaches for all, the kidney communities strive to prevent kidney diseases and enable living well with kidney disease.

The Kidney Disease: Improving Global Outcomes (KDIGO) Clinical Practice Guideline for the Management of Glomerular Diseases is an update to the KDIGO 2012 guideline. The aim is to assist clinicians caring for individuals with glomerulonephritis (GN), both adults and children. The scope includes various glomerular diseases, including IgA nephropathy and IgA vasculitis, membranous nephropathy, nephrotic syndrome, minimal change disease (MCD), focal segmental glomerulosclerosis (FSGS), infection-related GN, antineutrophil cytoplasmic antibody (ANCA) vasculitis, lupus nephritis, and anti-glomerular basement membrane antibody GN. In addition, this guideline will be the first to address the subtype of complement-mediated diseases. Each chapter follows the same format providing guidance related to diagnosis, prognosis, treatment, and special situations. The goal of the guideline is to generate a useful resource for clinicians and patients by providing actionable recommendations based on evidence syntheses, with useful infographics incorporating views from experts in the field. Another aim is to propose research recommendations for areas where there are gaps in knowledge. The guideline targets a broad global audience of clinicians treating GN while being mindful of implications for policy and cost. Development of this guideline update followed an explicit process whereby treatment approaches and guideline recommendations are based on systematic reviews of relevant studies, and appraisal of the quality of the evidence and the strength of recommendations followed the “Grading of Recommendations Assessment, Development and Evaluation” (GRADE) approach. Limitations of the evidence are discussed, with areas of future research also presented.

Atypical hemolytic uremic syndrome (aHUS) is an ultra-rare disease. The development of the disease is preceded by various triggers: infection, diarrhea, systemic pathology, and pregnancy. Pregnancy-associated aHUS accounts for 1/3 of all cases in adults. Obstetric aHUS (O-aHUS) have special features, severe course, and a high risk of an unfavorable outcome compared to "population-wide" aHUS. Aim: to compare the characteristics of the development, course, and outcomes of obstetric and non-obstetric aHUS in adults. Patients and methods: the study included 161 patients(pts) with an established diagnosis of aHUS who were observed in various medical institutions of the Russian Federation from 2012 to 2021: 76 pts with O-aHUS and 85 adult pts with non-obstetric aHUS. Results: in the O-aHUS group there were more pronounced signs of microangiopathic hemolysis (LDH 2487.0 vs 815.0, p<0.001]), a lower number of platelets (48.0 vs 84.5 <0.001), and more severe multiple organ failure (mean number of affected organs 3.64 vs 2.57, p<0.001). Kidney damage in all pts was presented by AKI requiring dialysis treatment in 136 cases (84.5%). The SСr values were higher in non-obstetric aHUS (758.0 vs 441.0 μmol/L, p<0.001). In the O-aHUS group all pts received fresh frozen plasma and 46 pts (60.5%) - complement-blocking drug Eculizumab (Ecu+). In the non-obstetric aHUS group only 53% of pts received plasma therapy, and 20% - Ecu+. Among pts with O-aHUS an improvement in renal function was noted in 78.3% of women Ecu+ and in 56.6% of pts receiving plasma therapy alone. In this group 12 pts died: 9 did not receive Eculizumab (30%), and 3 - Ecu+ (6.5%). In the non-obstetric aHUS group improvement in renal function was observed in 52.9% of pts Ecu+ and in 33.8% who did not receive pathogenetic therapy. Remained dialysis-dependent or died, respectively, 7 (41.2%), and 1 (5.9%) of 17 Ecu+, and 36 (52.9%) and 10 (13.2%) among 68 pts who did not receive Eculizumab. Conclusion: this study confirmed the existence of differences during obstetric and "general population" aHUS. Early initiation of Eculizumab allows patients to survive and achieve remission in both obstetric and non-obstetric aHUS.

Background: Bartter's syndrome (hypokalemic hypochloremic metabolic alkalosis) is a very rare autosomal recessive salt-losing tubulopathy caused by a defect in sodium and chloride reabsorption in the thick ascending limb of Henle's loop and distal convoluted tubules. Recently, it has become apparent that the clinical classification of Bartter's syndrome does not always match to the clinical symptoms associated with its gene-specific type. So, the most common genetic type 3 reveals phenotypic variety with a clinical course of not only classical, but also antenatal / neonatal Bartter's syndrome or Gitelman-like syndrome. The aim of our study was to investigate the phenotypic and genotypic variability of Bartter's syndrome, as well as the relationship of the phenotype and genotype with the efficacy of therapy and outcomes in children. Materials and methods: the group of 7 children (median age of disease onset 0.1 years, median diagnosis 3.0 years) from unrelated marriages with clinically established Bartter syndrome. Arterial hypertension and hearing loss were absent in all patients included in the study. Results: 5 (72%) of 7 patients were diagnosed with Bartter syndrome type 3 (causative variants in the CLCNKB gene) using molecular genetic analysis, 1 (14%) - type 2 (causative variants in the KCNJ1 gene), and for one child a study not completed. Correlations between the type of mutations and the phenotype were not revealed in the group of patients with genetic type 3, possibly due to a small number of patients. Two patients with type 3 Bartter's syndrome and missense mutations in the CLCNKB gene showed progression to stage 4 chronic kidney disease, 6 years later and 15.5 years after the onset of the disease. Continuous therapy with indomethacin was received by 3 children, potassium chloride - 7 patients. All children achieved stable compensation of water-electrolyte disturbances, acid-base balance. Conclusion: Bartter's syndrome type 3, represented by mutations in the CLCNKB gene, is the prevailing genetic variant and reveals a great phenotypic heterogeneity, which confirm the need for molecular genetic study of patients, including those with an already confirmed clinical diagnosis.

An actual challenge of current nephrology and immunology is the identification of new biomarkers that can be used as the potential key pathogenetic targets for monitoring, predicting, and effective treatment of IgA-nephropathy. The role of B-lymphocytes and αβТ-helpers in IgA-nephropathy immunopathogenesis is well studied. A promising direction is the investigation of mechanisms of non-classical γδТ-lymphocytes involvement, the effector role of which has been demonstrated in many autoimmune diseases. The aim of the work was to assess the phenotypic and functional characteristics of γδT-lymphocytes in the peripheral blood of patients with IgA-nephropathy. Materials and methods. The material of the study was the peripheral venous blood of 27 patients with IgA-nephropathy, which was confirmed by histological examination of biopsies using the Oxford classification (MEST-C). Phenotypic and functional markers of peripheral blood lymphoid cells were identified by the flow cytometry method. The data were processed using the Statistica 8.0 software. Results. The increase in the γδT-lymphocytes number (p<0.01) with a predominant cytotoxic CD8+CD56+CD314+ phenotype was established in association with the expansion of effector memory γδT-cells percentage (p<0.05) in peripheral blood of patients with IgA-nephropathy compared with healthy donors. The level of the killer receptor CD314 expression on γδT-cells correlated with the glomerular filtration rate under 60 ml/min (R= -0.62, p<0.01). It was shown that predominantly in patients with a high level of proteinuria (>500 mg/day) the number of effector memory γδT-cells exceeded their number in the group of patients with a low risk of progressive decline in renal function (p<0.05) and correlated with the severity of renal tissue morphological damage, in particular, mesangial proliferation (R=0.60; p<0.01) and segmental glomerulosclerosis (R=0.61; p<0.01). Conclusion. The functional profile of γδТ-lymphocytes can be used as a biomarker of the high risk of IgA-nephropathy progression as well as a therapeutic target for the subsequent development of specific immune-correction therapy.

Introduction: Malnutrition is one of the most common causes of mortality and morbidity in dialysis patients. This study aimed to evaluate the correlation between nutritional indices and hemodialysis adequacy. Material & Methods: This descriptive cross-sectional study was performed on 257 patients undergoing chronic hemodialysis in 6 dialysis centers in Zanjan province, Iran. Patients were selected by convenience sampling. Blood samples were examined in a single laboratory. Anthropometric indices included BMI, TSF, MAC and MAMC. Data were analyzed using descriptive statistics, t-test, and Spearman correlation coefficient with SPSS software version 22. Results: The nutritional indices in hemodialysis patients were in an acceptable range. The mean BMI of patients was 23.38±4.11 kg/m2. The mean serum albumin index was 4.18±0.91 g/dl. Serum total protein index was 7.2±1.11 mg/dL. In 90.3% of patients the creatinine (Cr) was <12 mg/dL. The arm circumference (MAC) index was between 60-90 percent of normal. Mid-arm muscle circumference (MAMC) in >50% of the patients was between 60-90% of normal. The skinfold thickness of the triceps (TSF) was 9.33±4.52 mm. BMI had negative correlation with kt/v (r=-0.17, P=0.005) and URR (r=-0.15, P=0.01). There was a positive correlation between protein index and URR (r=0.14, P=0.02). Conclusion: Some nutritional indices in hemodialysis patients are related to dialysis adequacy. This finding shows the need for careful monitoring of patients' nutritional status between dialysis sessions. The findings of the study on the nutritional status and adequacy of dialysis indicate the proper planning of dialysis centers with skilled professionals and the existence of up-to-date technology.

The aim: to study the relationship of elevated alanine aminotransferase (ALT) and/or aspartate aminotransferase (AST) at admission with the prevalence, risk of development, and the course of acute kidney injury (AKI) in patients with a novel coronavirus infection (COVID-19). Materials and methods. A retrospective analysis of the register of patients with COVID-19 was performed. We included patients with the laboratory-confirmed infection, the presence of the typical computer tomography (CT) picture, and assessment of the AST, ALT levels within 48 hours. Definition of AKI was based on KDIGO criteria. Results. 828 patients were included, 51% were male, the mean age was 65±16 years, arterial hypertension (HTN) was diagnosed in 70%, diabetes mellitus - in 26%, chronic kidney disease (CKD) - in 8%. In-hospital mortality was 21%. The AKI incidence was 27%, the most episodes were related to community-acquired AKI (CA-AKI) (16% and 11%). 16% of patients had hematuria at admission, 33% - proteinuria. At admission, 41% of patients had abnormal level of aminotransferases. These patients had higher levels of inflammatory markers, d-dimer, the higher frequency of proteinuria at admission (41% vs 27%, p<0.001), AKI (33% vs 23%, p=0.003) and in-hospital mortality (24.6% vs 18.2%, p=0.03). Clinical outcomes were poorer in the group with a predominant elevated AST, such as intensive care unit hospitalization (35% vs 29%), the need for mechanical ventilation (21% vs 16%), vasopressor support (12% vs 10%), progression of lung lesion by CT (25% vs 20%), in-hospital mortality (26% vs 18%) and the AKI incidence (35% vs 25%). Multinomial logistic regression found that HTN, CKD, elevated AST and hematuria were shown to be associated with CA-AKI, and age over 65 years HTN, oncology, elevated AST and hematuria were predictors of hospital-acquired AKI (HA-AKI). Conclusions. AKI incidence was statistically higher in patients with elevated aminotransferases at admission. Patients with predominant elevated AST were more likely to have adverse outcomes, AKI, than patients with elevated ALT. Elevated AST at admission was associated with CA-AKI and was a predictor of HA-AKI in hospitalized patients with COVID-19.

Currently, many classifiers claim to be markers that enable to detect (screening markers) or confirm a disease (diagnostic or prognostic markers). Accuracy (Acc) is a metric that is often used to evaluate the effectiveness of a diagnostic test, representing the proportion of correct classifications. Although Acc is widely used in publications as a measure of test effectiveness, in fact, it isn`t so. Moreover, Acc can reach large values even if a marker and an outcome are completely not conjugated. A more balanced estimate is the Matthews correlation coefficient (MCC). Another interesting evaluation metric is F-measure, in particular - the traditional F1-score. The F1-measure is a balanced average (harmonic mean) of sensitivity (or "recall") and positive predictive value (or "precision"). This metric allows us to more fully assess the ability of the test to recognize patients with the disease, but not to discriminate between sick and healthy subjects, since it does not consider true negative results. In the case when the marker is not binary, but a continuous quantitative variable, it is important to identify a cut-off threshold that allows us to solve certain tasks in a more effective way using the test (to classify subjects as sick or healthy based on the marker value). Traditionally, ROC analysis is used for this purpose, choosing the optimal threshold value of a quantitative variable based on the Yuden index (the maximum distance from the diagonal reference line on the ROC curve graph) or the K-index (the minimum distance from the ROC curve to the upper left corner of the graph). Such a utilitarian approach is applicable when the threshold provides high values of both sensitivity and specificity (more than 0.9). In most cases, the threshold is chosen based on the maximization (or achievement of the minimum acceptable value) of certain estimates, such as sensitivity, specificity, positive or negative predictive value, relative risk or odds ratio, likelihood ratio, etc., which allows using the marker to carry out certain tasks.

Caused by a variety of factors, poor hemodialysis (HD) tolerability is common in the population of hemodialysis patients and may significantly reduce their quality of life. Critical myocardial ischemia induced by intradialytic hemodynamic stress, and causative for HD intolerance is a rare, but life-threatening complication. Atypical clinical manifestations of myocardial ischemia in young patients could result in underestimation of acute coronary syndrome and sudden cardiac death risks. A 39-year-old female was admitted to the hospital complaining at severe fatigue and dizziness after every HD-session and during fitness activities. Back in 2002, she was diagnosed with systemic lupus erythematosus (SLE) and received glucocorticoids (GC) for a long time. Her lupus nephritis progressed to the end stage of kidney disease by 2007, and maintenance HD (MHD) was initiated. Kidney transplantation was performed in 2011, and she received standard immunospuression. Since 2017 she demonstrated progressive loss of the transplant function (chronic graft rejection), two years later transplantectomy was performed, and she re-started MHD via tunneled central venous catheter, because of repeated arteriovenous fistulas thrombosis occurred due to secondary antiphospholipid syndrome (APS) despite the anticoagulant therapy. At admission, ECG showed features of left ventricular (LV) hypertrophy and the isoelectric ST segment. Echocardiography (Echo-CG) confirmed preserved LV systolic function and absence of regional contractile impairment, though signs of marked LV hypertrophy and moderate calcification without severe valvular dysfunction were detected. Echo-CG and a Holter monitor (HM) test were performed during the HD session (intradialytic cardiac monitoring) to evaluate HD hemodynamics and identify the reasons for poor HD tolerability. Echo-CG was performed twice - 2 hours after the start of the HD session (‘hemodynamic stability’) and 30 min before the end of the session (‘hemodynamic stress’). HM-ECG data were analyzed for 12 hours, including HD time (fig. 1a, HM fragment before the session, isoelectric ST segment, HR 60). First intra-dialysis Echo-CG showed no signs of negative dynamics. The patient complained of increasing fatigue and dizziness 30 min before the end of HD, with arterial BP remaining within the normal range. Second Echo-CG detected regional hypokinesis progression in mid and apical segments of anterior and lateral LV walls (fig. 2, regional hypokinesis indicated by arrows). HM data showed a horizontal ST depression (>2.5 mm, HR 90) (fig. 1b). These findings of the intradialytic monitoring alongside with the patient’s complaints were interpreted as an atypical heart attack with transient myocardial ischemia, followed by a decision to perform a coronary angiography (CA). Critical stenosis (>85%) of the proximal segment of the left anterior descending artery was found (fig. 3, 3a oval zoom, the stenosis area is marked with an arrow). The coronary blood flow was completely restored after stenting the stenosis area (fig. 3b, 3b oval zoom, the stented segment is marked with an arrow). After the coronary intervention, the patient tolerates HD well and stays physically active in everyday life. Thus, the reported intradialytic hemodynamic stress acted as a stress test, inducing critical myocardial ischemia. The clinical manifestations of the painless myocardial ischemia were severe fatigue and dizziness at the end of the HD session. In terms of cardiorenal interactions, a periprocedural hemodynamic stress should be considered as a trigger of the coronary heart disease destabilization, commonly asymptomatic in everyday life. Early development and progression of coronary atherosclerosis in a young female patient may occur due to the multiple mutually aggravating causes: complicated SLE course, secondary APS, long-term treatment with GC and MHD vintage. The authors declare no conflict of interest.

The letter focuses on the issues of insufficient standardization of methods for determination of intact parathyroid hormone (iPTH) level. The use of the recommended diagnostic thresholds of iPTH expressed as a ratio to the upper reference limit for the method does not provide sufficient harmonization of the results. This is possibly explained by the variability of the reference groups used by the manufacturer to develop the reference limits specified in the instructions for reagents. When using iPTH 2nd generation assays manufactured by Roche and Abbott for a parallel study of a series of the same samples, despite the similarity of upper reference limit values specified in the instructions (Roche Cobas e601: 15-65 pg/ml; Abbott Architect i2000 and/or Alinity i: 15-68.3 pg/ml), whose ratio is close to 1 (1,048), more significant differences were revealed. The ratio of the results in measuring the concentration of iPTH in pg/ml using Abbott Alinity i (y) and Roche Cobas 601e (x) technologies in the same sample series (n=70, including 40 samples of dialysis patients) is described by the regression equation y = 1.255x + 3.79. Using Abbott Alinity technology in a reference group of practically healthy individuals with no vitamin D deficiency we developed the reference limits for intact PTH, which were 1.3-9.7 ng/ml (12.3-91.5 pg/ml). According to the reference limits developed in own conditions, the clinically significant thresholds of 1x, 2x, 4x, 9x from the upper reference limit for Abbott (Architect, Alinity) iPTH technologies in concentration units are approximately 90-180-350-800 pg/ml.