Search Results (908)

Nephrotic syndrome (NS) is characterized by proteinuria, hypoalbuminemia, edema, and hyperlipidemia. Apart from the traditional causes of NS, such as minimal change disease, focal segmental glomerulosclerosis, diabetes, infections, malignancies, autoimmune conditions, and nephrotoxic agents, there are also rare causes of NS, whose knowledge is of the utmost importance. The aim of this article was to highlight the less well-known causes that have a significant impact on diagnosis and treatment. Genetic syndromes such as Schimke immuno-osseous dysplasia, familial lecithin-cholesterol acyltransferase deficiency with two clinical variants (fish-eye Disease and the p.Leu364Pro mutation), lead to NS through mechanisms involving podocyte and lipid metabolism dysfunction. Congenital disorders of glycosylation and Nail–Patella Syndrome emphasize the role of deranged protein processing and transcriptional regulation in glomerular injury. The link of NS with type 1 diabetes, though rare, suggests an etiology on the basis of common HLA loci and immune dysregulation. Histopathological analysis, particularly electron microscopy, shows mainly podocyte damage, mesangial sclerosis, and alteration of the basement membrane, which aids in differentiating rare forms. Prompt recognition of these novel etiologies by genetic analysis, renal biopsy, and an interdisciplinary panel is essential to avoid delays in diagnosis and tailored treatment. Full article

Kidney transplantation is the treatment of choice for patients with end-stage kidney disease. Despite significant advances in graft survival, rejection continues to pose a major clinical challenge. Conventional monitoring tools, such as serum creatinine, donor-specific antibodies, and proteinuria, lack sensitivity and specificity for early detection of graft injury. Moreover, while biopsy remains the current gold standard for diagnosing rejection, it is prone to confounders, invasive, and associated with procedural risks. However, non-invasive novel biomarkers have emerged as promising alternatives for earlier rejection detection and improved immunosuppression management. This review focuses on the leading candidate biomarkers currently under clinical investigation, with an emphasis on their diagnostic performance, prognostic value, and potential to support personalised immunosuppressive strategies in kidney transplantation. Full article

IgA nephropathy is the most common primary glomerulonephritis, with pathohistological changes described by the Oxford classification, while the Banff classification is used in transplant pathology. This study included 253 patients with IgA nephropathy in native kidneys, divided into the pediatric (n = 105) and adult (n = 148) groups. It aimed to examine clinical, and Oxford and Banff morphological parameters in relation to age, correlations of clinical data with pathohistological parameters, and predictors of the disease outcome. Pediatric patients more frequently presented with macroscopic hematuria, while adults showed higher urea and creatinine levels, and lower eGFR. Examining Oxford classification parameters, chronic glomerular and tubulointerstitial lesions were more common in adults. Banff parameters revealed more frequent chronically active glomerular, inflammatory, chronic tubulointerstitial, and vascular lesions in adults. All inflammatory, chronic tubulointerstitial, and vascular parameters correlated with serum urea levels, eGFR and CKD stage in adults, while less frequent in pediatric patients. Tubulointerstitial Oxford and Banff parameters were strong predictors of CKD and proteinuria progression in children, while such predictors were fewer in adults; segmental glomerulosclerosis predicted hematuria progression in adults. Banff parameters (cg, t, ti, i, i-IFTA, ptc, cv), not in Oxford classification, significantly predict outcomes and are recommended for incorporation into IgA nephropathy reports. Full article

Membranous nephropathy (MN) is the most prevalent cause of nephrotic syndrome (NS) in adults, and it can be primary (idiopathic) with an unknown cause or secondary due to a variety of conditions (lupus, infections, malignancies, medications, etc.). It progresses to chronic kidney disease (CKD) in up to 60% of patients, and 10 to 30% develop end-stage kidney disease (ESKD). This retrospective study examines the importance of specific factors, including baseline demographic and clinical data, kidney biopsy PH findings, and selected biochemical parameters, influencing MN outcomes after 10 years of follow-up. The cohort included 94 individuals in whom a diagnosis of MN was established by percutaneous biopsy of the left kidney’s lower pole at the University Clinical Center of Serbia (UCCS) between 2008 and 2013. According to the outcomes, patients were divided into three groups: the recovery (Rec) group, with complete remission, including normal serum creatinine (Scr) and proteinuria (Prt), the group with development of chronic kidney disease (CKD), and the group with development of end-stage kidney disease (ESKD). Nephropathologists graded pathohistological (PH) results from I to III based on the observed PH findings. During the follow-up period, 33 patients were in the Rec group, CKD developed in 53 patients, and ESKD developed in 8 patients. Baseline creatinine clearance levels (Ccr), Scr, and uric acid (urate) were found to be significantly associated with the outcomes (p < 0.001). The lowest values of baseline Scr and urate were observed in the Rec group. The presence of acute kidney injury (AKI) or CKD at the time of kidney biopsy was associated with the more frequent development of ESKD (p = 0.02). Lower Ccr was associated with a higher likelihood of progressing to CKD (B = −0.021, p = 0.014), whereas older age independently predicted progression to ESKD (B = 0.02, p = 0.032). Based on this study, it was concluded that the most important biochemical and clinical factors that are associated with the outcomes of this disease are the values of Scr, Ccr, and urate and the existence of CKD at the time of kidney biopsy. Unlike most previous studies, the presence of HTN had no statistical significance in the outcome of the disease. Full article

Preeclampsia (PE) is a multifactorial hypertensive disorder unique to pregnancy and a leading cause of maternal and fetal morbidity and mortality worldwide. Its pathogenesis involves placental dysfunction and an exaggerated maternal inflammatory response. Uric acid (UA), traditionally regarded as a marker of renal impairment, is increasingly recognized as an active contributor to the development of PE. Elevated UA levels are associated with oxidative stress, endothelial dysfunction, immune activation, and reduced renal clearance. Clinically, UA is measured in the second and third trimesters to assess disease severity and guide obstetric management, with higher levels correlating with early-onset PE and adverse perinatal outcomes. Its predictive accuracy improves when combined with other clinical and biochemical markers, particularly in low-resource settings. Mechanistically, UA and its monosodium urate crystals can activate the NLRP3 inflammasome, a cytosolic multiprotein complex of the innate immune system. This activation promotes the release of IL-1β and IL-18, exacerbating placental, vascular, and renal inflammation. NLRP3 inflammasome activation has been documented in placental tissues, immune cells, and kidneys of women with PE and is associated with hypertension, proteinuria, and endothelial injury. Experimental studies indicate that targeting UA metabolism or inhibiting NLRP3 activation, using agents such as allopurinol, metformin, or MCC950, can mitigate the clinical and histopathological features of PE. These findings support the dual role of UA as both a biomarker and a potential therapeutic target in the management of the disease. Full article

Idiopathic childhood nephrotic syndrome is a common glomerulopathy comprising proteinuria, hypoalbuminemia, and edema. Podocyte dysfunction is central to this disease process. Extracellular vesicles are released from stressed cells and can represent a molecular snapshot of the parent cell of origin. We previously showed that urinary large extracellular vesicles (LEVs) derived from podocytes are increased in patients with nephrotic syndrome relapse. Here, we investigated the role of mitochondrial DNA (mtDNA) within LEVs both in vitro and in vivo, revealing the novel finding that podocytes release LEVs containing mtDNA, driven by mitochondrial stress. A puromycin aminonucleoside nephrosis rat model showed foot process effacement on electron microscopy and urinary LEVs with significantly increased mtDNA. Prednisolone, which drives remission in nephrotic syndrome in children, attenuated mitochondrial stress and reduced the amount of mtDNA content within LEVs in vitro. Lastly, urinary LEVs from children with nephrotic syndrome also contain mtDNA, and it is the podocyte LEV-fraction which is preferentially enriched. Overall, these data support a potential mechanism of podocyte mitochondrial stress in non-genetic, idiopathic pediatric nephrotic syndrome. Full article

Systemic lupus erythematosus (SLE) is a chronic inflammatory autoimmune disease characterized by tissue damage in multiple organs caused by autoantibodies and the resulting immune complexes. One possible way for complement system contribution to onset of autoimmune disorder could be realized by the impairment of C1q-mediated apoptotic clearance as part of human homeostasis. The capacity of C1q to bind early apoptotic cells could be decreased or even lost in the presence of anti-C1q antibodies. A monoclonal anti-idiotypic single-chain (scFv) antibody was selected from the phage library Griffin1” to recognize anti-C1q autoantibodies, purified from sera of lupus nephritis patients. Lupus-prone MRL/lpr mice were injected weekly with scFv A1 fragment-binding anti-C1q antibodies. The number of in vitro and ex vivo studies with collected cells, sera, and organs from the treated animals was performed. scFv treatment changed the percentage of different B-, T-, and NK-cell subpopulations as well as plasma cells and plasmablasts in the spleen and bone marrow. An increase in the levels of splenocyte proliferation, anti-C1q antibodies, and the number of plasma cells producing anti-dsDNA and anti-C1q antibodies were also observed in scFv-treated animals. High levels of proteinuria and hematuria combined with unstable levels of IL10 and IFNγ promote the development of severe lupus and shorten the survival of treated MRL/lpr mice. Therapy with the scFv A1 antibody resulted in BCR recognition on the surface of anti-C1q-specific B-cells and had a disease progression effect, enhancing lupus symptoms in the MRL/lpr mouse model of SLE. Full article

Background: N^ε-(carboxymethyl)-lysine (CML) is formed in the human body by non-enzymatically driven reactions including glycation, oxidation, and lipoxidation. CML is a ubiquitous product of normal physiology, but its levels are increased under disease conditions like chronic kidney disease (CKD) and diabetes mellitus (DM). Free CML is eliminated from the human body mainly through kidney excretion, and its accumulation in the kidney tissue is linked to CKD pathogenesis. Aim: The main goal of this study was to evaluate the relative contribution of CKD and Type 2 DM (T2DM) to the accumulation of CML in patients’ sera. Methods: The study included 22 patients with CKD without DM, 55 with CKD and comorbid T2DM, and 21 with T2DM without CKD. Serum CML levels were measured by ELISA. The Kruskal-Wallis test was used to detect differences among groups. Spearman correlation analysis was performed, and the one-tailed Dunn test was considered to indicate statistical significance at p < 0.05. Results: The median serum CML levels (CKD, 658.4 ± 434.3 ng/mL; CKD + T2DM, 431.3 ± 327.9 ng/mL; T2DM, 273.9 ± 134.2 ng/mL) differed significantly (p < 0.05) among the three patient groups. A positive correlation was observed between serum CML and microalbuminuria (p = 0.004; r = 0.58), proteinuria (p = 0.002; r = 0.6), and age (p = 0.007; r = 0.52) only in the CKD patients. In all T2DM patients, independent of CKD status, serum CML correlated negatively (p < 0.05) with postprandial glucose and duration of diabetes, while its correlation with fasting glucose and HbA1c was negative only in the T2DM cohort without CKD. Conclusions: In patients with CKD, higher levels of CML were observed compared to those with T2DM. Serum CML correlated positively with proteinuria, albuminuria, and patient age in non-diabetic CKD patients, and negatively with blood glucose, HbA1c, and DM duration of T2DM in patients without CKD. Full article

Background: Neonates, particularly those born prematurely or with low birth weight, face an elevated risk of developing Acute Kidney Injury (AKI) due to various factors. Perinatal and maternal considerations, often linked to preterm delivery, contribute to this heightened risk. Methods: A retrospective study of neonates admitted to the intensive care unit at a single Israeli Hospital who were diagnosed as having AKI. The study includes follow-up data on these children. Results: During the study period, 971 neonates were admitted to the Pediatric Intensive Care Unit (PICU), and 47 cases had a documented diagnosis of AKI. Thirty-four of them had available long-term data and were included in this analysis. A total of 13 out of 26 subjects with available blood pressure measurements had high blood pressure for their age percentile compatible with the definition of hypertension, and 6 out of 34 (17.6%) had proteinuria. Conclusions: These findings underscore the importance of increased clinical awareness and structured long-term follow-up for neonates who experience AKI. Full article

Focal and segmental glomerulosclerosis (FSGS) describes a histological pattern of injury seen by light microscopy in kidney biopsy specimens and is the end result of various injuries to the podocyte. Our understanding of this disease entity has evolved greatly since it was first described, with particular focus on changes in the classification of FSGS as a disease entity and expansion in our understanding of the underlying pathophysiology. The incidence and prevalence of FSGS and FSGS-associated end-stage kidney disease (ESKD) have increased globally, particularly in the United States; it is now the most common primary glomerular disorder in those with ESKD. APOL-1 is likely responsible for this epidemiological trend in kidney disease in the US and is an important focus of clinical trials and potential targeted therapies. Currently, the goal of treatment in FSGS is to achieve remission of proteinuria and to prevent progression to ESKD. Remission is achieved by using immunosuppressive therapies in primary FSGS, but treatment in secondary and genetic FSGS is largely supportive. Recurrent FSGS (rFSGS) post-transplantation remains a significant clinical challenge to nephrologists; current monitoring and treatment strategies are based on retrospective meta-analysis and observational studies with no clear consensus as to the optimum approach. Emerging therapies are focused on developing more targeted interventions in genetic and secondary FSGS. This review article aims to comprehensively explore this multifaceted disease entity. Full article

Background: Fabry disease (FD) is an X-linked lysosomal storage disorder caused by mutations in the GLA gene, resulting in α-galactosidase A (α-Gal A) deficiency and progressive accumulation of globotriaosylceramide (Gb3). Current therapies, such as enzyme replacement and chaperone therapy, have limitations, including incomplete biodistribution and mutation-specific efficacy. Gene therapy using adeno-associated virus (AAV) vectors presents a promising alternative. Methods: In this study, we assessed the dose-dependent effects of AAV8 and AAV9 vectors encoding human GLA in Gla knockout (Gla^−/y) mice by measuring α-Gal A activity and monitoring safety. To evaluate therapeutic efficacy, symptomatic Fabry mice (G3S^Tg/+Gla^−/y) were used. Results: AAV9-GLA produced significantly higher and more sustained enzyme activity than AAV8-GLA across plasma, liver, heart, and kidney. In symptomatic mice, AAV9-GLA achieved superior reductions in serum Gb3 and lyso-Gb3 levels, greater Gb3 clearance in heart and kidney tissues, and improved proteinuria. Anti-GLA IgG titers remained below threshold for the first four weeks and increased modestly by week eight, indicating a limited humoral immune response. No significant clinical signs or weight loss were observed in Gla^−/y mice over the 3.5-month study period, supporting the favorable safety profile of AAV-mediated gene therapy. Conclusions: These findings demonstrate that AAV9 provides enhanced biodistribution and therapeutic efficacy compared to AAV8, supporting its potential for the treatment of Fabry disease. Full article

Obesity, hypertension, and chronic kidney disease (CKD) constitute the deadly trinity of modern threats for populations of both developed and developing countries. These diseases (together with type 2 diabetes) are closely linked in their pathophysiology and result in increasing cardiovascular (CV) morbidity and premature death from CV causes. In this review, we focused on the kidney as the target of obesity-related disorders. Obesity-related glomerulosclerosis (ORG) represents a pattern of renal injury caused solely or predominantly by obesity; usually, it is superimposed on chronic kidney disease (CKD) from other causes, such as diabetic kidney disease, hypertensive kidney disease, type 2 cardiorenal syndrome, primary or secondary glomerulopathies, and others. Adipose tissue contributes to kidney injury in several ways: it releases proinflammatory cytokines and growth factors, leading to podocyte and mesangial cell injury and glomerulosclerosis. In particular, perirenal adipose tissue (PRAT), besides exerting paracrine and endocrine effects on the kidney, modifies its function via compression on renal parenchyma and vessels. The intrinsic ability of the kidneys in obesity to increase the reabsorption of sodium warrants intraglomerular hypertension and hyperfiltration, followed by progressive renal injury. Lifestyle interventions and pharmacological agents, as well as metabolic (bariatric) surgery resulting in weight reduction, may also be beneficial for the kidneys. Using GLP1 receptor agonists (with a special focus on subcutaneous semaglutide and tirzepatide) seems to be the most promising treatment strategy for preventing kidney injury in obese individuals. Full article

Background/Objectives: Automation improves efficiency in laboratory workflow but may fail to detect clinically relevant abnormalities in patients with nephropathy. This study aimed to identify dipstick parameters associated with nephropathy-related sediment findings and to propose practical criteria to guide manual microscopy review based on these associations. Methods: Urine samples from in- and outpatients, primarily from the nephrology unit, were collected at a university hospital from July 2022 to September 2023. Samples were analyzed within two hours using LabUMat 2 and UriSed 3 analyzers. Manual microscopy was performed on all specimens by two experienced technicians. Sediments were classified as suggestive or not of nephropathy based on hematuria with dysmorphism, hyaline and pathological casts, lipiduria, or renal tubular epithelial cells. Results: Of 503 samples, 146 (29%) showed sediment findings indicative of nephropathy, which were significantly associated with dipstick positivity for protein and blood. Among nephropathy samples, 71.2% had protein ≥1+ or blood ≥2+. Using this combination as a criterion for manual sediment review yielded a sensitivity of 71.2%, a specificity of 73.9%, and a 3.84-fold increased relative risk of detecting nephropathy-related elements (p < 0.001). The criteria performed best among nephrology outpatients, with sensitivity of 79.5%, specificity of 63.9%, and relative risk of 3.91 (p < 0.001). Conclusions: Dipstick protein ≥1+ or blood ≥2+ helps identify patients who may benefit from manual sediment review, supporting diagnostic accuracy in nephropathy. Each institution should define its criteria based on patient profile, analytical methods, and workflow. Full article

Background: Preeclampsia (PE) remains a significant cause of maternal and fetal morbidity and mortality, with diagnostic criteria still evolving. Serum albumin, a potential marker of endothelial dysfunction and protein loss, has been proposed as a severity indicator in PE. This study evaluates the clinical utility of serum albumin levels, particularly values below 2 g/dL, in assessing PE severity and predicting maternal–fetal complications. Methods: We conducted a prospective and descriptive study including 59 pregnant women diagnosed with PE. The participants were divided into mild (n = 23) and severe (n = 36) PE groups based on national guidelines. Serum albumin, 24 h proteinuria, renal and hepatic function markers, and fetal outcomes were analyzed. ROC curve analysis was employed to determine albumin’s diagnostic performance. Results: Serum albumin levels were significantly lower in the severe PE group compared to the mild PE group (1.82 ± 0.50 vs. 2.44 ± 0.36 g/dL, p < 0.001). ROC analysis identified a threshold of 2.3 g/dL (sensitivity: 88.9%, specificity: 73.9%) for distinguishing PE severity. A strong association was observed between albumin < 2 g/dL and severe proteinuria (>3 g/24 h), but no significant association emerged with renal or hepatic dysfunction, fetal complications, or birth outcomes. Conclusions: Although serum albumin < 2 g/dL is associated with severe proteinuria, it does not independently correlate with other maternal or fetal complications in PE. These findings suggest that albumin may serve as a complementary, but not a standalone, marker in assessing PE severity. Full article

Unilateral renal agenesis (URA) is a urinary tract congenital anomaly characterized by a congenital absence or early developmental arrest of only one kidney. In the presence of a normal contralateral kidney, URA is typically considered a condition of minimal clinical significance as the solitary kidney often undergoes hypertrophy and can sufficiently perform the needed renal function after birth. However, postnatal studies suggest that URA has a significant association with other urinary and extra-urinary anomalies and may have implications for long-term health. This descriptive review focuses on the perinatal aspects of URA, emphasizing the main ultrasound findings to establish the prenatal diagnosis and to guide perinatal management. The pediatric implications of this diagnosis, particularly the high prevalence of long-term complications including hypertension, proteinuria, and a decreased glomerular filtration rate, are also briefly reviewed. URA is consistently associated with other ipsilateral urogenital anomalies. In females, there is a significant association with uterine anomalies that has significant implications for subsequent reproductive function. In males, the prevalence of both urinary and genital anomalies is also increased, which may also have implications for future fertility. Prenatal ultrasound offers the possibility of early diagnosis and parental counseling, which may result in timely intervention to reduce contralateral renal damage, prevent severe urogenital manifestations and co-morbidities, and improve fertility and the quality of life. Full article