World journal of nephrology最新文献

The exponential rise in the burden of chronic kidney disease (CKD) worldwide has put enormous pressure on the economy. Predictive modeling of CKD can ease this burden by predicting the future disease occurrence ahead of its onset. There are various regression methods for predictive modeling based on the distribution of the outcome variable. However, the accuracy of the predictive model depends on how well the model is developed by taking into account the goodness of fit, choice of covariates, handling of covariates measured on a continuous scale, handling of categorical covariates, and number of outcome events per predictor parameter or sample size. Optimal performance of a predictive model on an independent cohort is desired. However, there are several challenges in the predictive modeling of CKD. Disease-specific methodological challenges hinder the development of a predictive model that is cost-effective and universally applicable to predict CKD onset. In this review, we discuss the advantages and challenges of various regression models available for predictive modeling and highlight those best for future CKD prediction.

Background: Kidney disease is a severe complication of diabetes that often leads to end-stage renal disease. Early diagnosis is crucial for prevention or delay. However, the current diagnostic methods, with their limitations in detecting the disease in its early stages, underscore the urgency and importance of finding new solutions. miRNAs encapsulated inside urinary exosomes (UEs) have potential as early biomarkers for kidney diseases. The need for reference miRNAs for accurate interpretation currently limits their translational potential.

Aim: To identify consistently expressing reference miRNAs from UEs of controls and patients with type 2 diabetesmellitus (T2DM) and biopsy-confirmed kidney diseases.

Methods: miRNA profiling was performed on UEs from 31 human urine samples using a rigorous and unbiased method. The UEs were isolated from urine samples collected from healthy individuals (n = 6), patients with T2DM (n = 13), and T2DM patients who also had kidney diseases (including diabetic nephropathy, n = 5; membranous nephropathy, n = 5; and IgA nephropathy, n = 2) through differential ultracentrifugation. After characterizing the UEs, miRNA expression profiling using microarray technology was conducted.

Results: Microarray data analysis identified 14 miRNAs that were consistently expressed in UEs from 31 human samples, representing various kidney conditions: diabetic controls, diabetic nephropathy, membrane nephropathy, IgA nephropathy, and healthy controls. Through in silico analysis, we determined that 10 of these miRNAs had significant potential to serve as reference genes in UEs.

Conclusion: We identified uniformly expressing UE miRNAs that could serve as reference genes kidney disease biomarkers.

Background: Flavonoids, the main class of polyphenols, exhibit antioxidant and antihypertensive properties.

Aim: To prospectively investigate the impact of flavonoids on arterial stiffness in patients with chronic kidney disease (CKD) stages I-IV.

Methods: In this prospective, single-arm study, CKD patients with arterial hypertension and diabetes mellitus were enrolled. Baseline demographic, clinical, and laboratory variables were recorded. Patients received daily treatment with a phenol-rich dietary supplement for 3 months. Blood pressure, arterial stiffness (carotid-femoral pulse wave velocity, central pulse pressure), and oxidative stress markers (protein carbonyls, total phenolic compound, total antioxidant capacity) were measured at baseline and at study end.

Results: Sixteen patients (mean age: 62.5 years, 87.5% male) completed the study. Following intervention, peripheral systolic blood pressure decreased significantly by 14 mmHg (P < 0.001). Carotid-femoral pulse wave velocity decreased from 8.9 m/s (baseline) to 8.2 m/s (study end) (P < 0.001), and central pulse pressure improved from 59 mmHg to 48 mmHg (P = 0.003). Flavonoids also reduced oxidative stress markers including protein carbonyls (P < 0.001), total phenolic compound (P = 0.001), and total antioxidant capacity (P = 0.013).

Conclusion: Flavonoid supplementation in CKD patients shows promise in improving blood pressure, arterial stiffness, and oxidative stress markers.

Background: Among diverse profound impacts on patients' quality of life (QoL), end-stage renal disease (ESRD) frequently results in increased levels of depression, anxiety, and stress. Renal replacement therapies such as hemodialysis (HD) and transplantation (TX) are intended to enhance QoL, although their ability to alleviate psychological distress remains uncertain. This research posits the existence of a significant correlation between negative emotional states and QoL among ESRD patients, with varying effects observed in HD and TX patients.

Aim: To examine the relationship between QoL and negative emotional states (depression, anxiety, and stress) and predicted QoL in various end-stage renal replacement therapy patients with ESRD.

Methods: This cross-sectional study included HD or TX patients in the Eastern Region of Saudi Arabia. The 36-item Short Form Survey and Depression Anxiety Stress Scale (DASS) was used for data collection, and correlation and regression analyses were performed.

Results: The HD and TX transplantation groups showed statistically significant inverse relationships between QoL and DASS scores. HD patients with high anxiety levels and less education scored low on the physical component summary (PCS). In addition, the results of the mental component summary (MCS) were associated with reduced depression. Compared with older transplant patients, TX patients' PCS scores were lower, and depression, stress, and negative working conditions were highly correlated with MCS scores.

Conclusion: The findings of this study revealed notable connections between well-being and mental turmoil experienced by individuals undergoing HD and TX. The PCS of HD patients is affected by heightened levels of anxiety and lower educational attainment, while the MCS of transplant patients is influenced by advancing age and elevated stress levels. These insights will contribute to a more comprehensive understanding of patient support.

Inflammatory bowel disease (IBD) is a chronic condition characterized by immune-mediated inflammation in the gastrointestinal tract, which follows a relapsing and remitting course. Apart from affecting the gastrointestinal tract, IBD also has extra-intestinal manifestations (EIMs). While the etiology of extraintestinal manifestation remains unclear, it is theorized to be based on immunological responses influenced by genetic factors. Renal involvement is one of the EIMs observed in ulcerative colitis and Crohn's disease. The renal manifestations in IBD patients encompass a range of conditions including nephrolithiasis, amyloidosis, tubulointerstitial nephritis, glomerulonephritis (GN), obstructive pathologies, and chronic kidney disease (CKD). The incidence of CKD in IBD patients varies from 5%-15%. The decline in renal function can stem from various factors such as direct inflammatory damage to the kidneys leading to glomerular or tubular injury, or from complications like recurrent stones, amyloidosis, or GN. Additionally, nephrotoxic medications used in treating IBD, such as TNF-α inhibitors, calcineurin inhibitors, and aminosalicylates, can exacerbate the decline in renal function. Currently, there is a lack of consensus regarding these patients' screening and renal function monitoring. This review aims to assess the existing literature on the different renal complications among individuals with IBD, shedding light on their pathophysiology and management.

Acute pyelonephritis (APN) is a bacterial infection resulting in kidney inflammation, typically arising as a complication of an ascending urinary tract infection that ascends from the bladder to the kidneys. Clinical diagnosis is generally based on clinical and laboratory findings. Recent guidelines recommend not performing diagnostic imaging unless a complicated APN is suspected or the infection affects high-risk patients such as the elderly, immunocompromised individuals, or diabetics. Contrast-enhanced ultrasound (CEUS) is a valuable tool in both the diagnosis and follow-up of APN. It aids in distinguishing small simple nephritic involvement from abscess complications and monitoring their evolution over time during antibiotic therapy. Given its lack of ionizing radiation and nephrotoxicity, CEUS is a valid diagnostic modality for approaching and monitoring pyelonephritis, improving early identification and characterization of inflammatory lesions. This review aims to summarize the main evidence on the use of ultrasound and CEUS in the diagnosis of APN and its follow-up.

Background: Hepatorenal syndrome (HRS) is the most prevalent form of acute kidney injury in cirrhotic patients. It is characterized by reduced renal blood flow and represents the most severe complication in cirrhotic patients with advanced disease. Previous research has indicated that antioxidants can delay the onset of a hyperdynamic circulatory state in cirrhosis and improve renal function in HRS patients. Regular omega-3 supplementation has significantly reduced the risk of liver disease. This supplementation could represent an additional therapy for individuals with HRS.

Aim: To evaluated the antioxidant effect of omega-3 polyunsaturated fatty acid supplementation on the kidneys of cirrhotic rats.

Methods: Secondary biliary cirrhosis was induced in rats by biliary duct ligation (BDL) for 28 d. We used 24 male Wistar rats divided into the following groups: I (control); II (treated with omega-3, 1 g/kg of body weight); III (BDL treated with omega-3, 1 g/kg of body weight); and IV (BDL without treatment). The animals were killed by overdose of anesthetic; the kidneys were dissected, removed, frozen in liquid nitrogen, and stored in a freezer at -80℃ for later analysis. We evaluated oxidative stress, nitric oxide (NO) metabolites, DNA damage by the comet assay, cell viability test, and apoptosis in the kidneys. Data were analyzed by one-way analysis of variance, and means were compared using the Tukey test, with P ≤ 0.05.

Results: Omega-3 significantly decreased the production of reactive oxygen species (P < 0.001) and lipoperoxidation in the kidneys of cirrhotic rats treated with omega-3 (P < 0.001). The activity of the antioxidant enzymes superoxide dismutase and catalase increased in the BDL+omega-3 group compared to the BDL group (P < 0.01). NO production, DNA damage, and caspase-9 cleavage decreased significantly in the omega-3-treated BDL group. There was an increase in mitochondrial electrochemical potential (P < 0.001) in BDL treated with omega-3 compared to BDL. No changes in the cell survival index in HRS with omega-3 compared to the control group (P > 0.05) were observed.

Conclusion: The study demonstrates that omega-3 can protect cellular integrity and function by increasing antioxidant enzymes, inhibiting the formation of free radicals, and reducing apoptosis.

Obstructive uropathy is defined as the structural or functional interruption of urinary outflow at any level in the urinary tract. It is regarded as one of the most prevalent causes of acute kidney injury (AKI), accounting for 5%-10% of cases. Acute severe obstruction of the urinary tract is a potentially threatening situation for the kidneys and therefore requires prompt identification and management to relieve obstruction. The aim of the present article is to review and synthesize available evidence on obstructive uropathy, providing a clinical guideline for clinicians. A literature review on obstructive uropathy in the context of AKI was performed, focusing on the least clarified aspects regarding diagnosis and management. Recent literature searching was conducted in English and top-level evidence articles including systematic reviews, metanalyses and large series were prioritized. Acute obstruction of the urinary tract is a diagnostic and therapeutical challenge that may lead to important clinical complications together with direct structural and hemodynamic damage to the kidney. Early recognition of the leading cause and its exact location is essential to ensure prompt urinary drainage together with the most suitable drainage technique selection. A multidisciplinary approach, including urologists, nephrologists, and other medical specialties, is best suited to correctly manage concomitant hemodynamic changes, fluid and electrolyte imbalances, and other related issues. Obstructive uropathy is one of the leading causes of AKI. Recognition of patients suitable for early diversion and feasibility or adequate selection of the indicated technique is sometimes challenging. A thorough understanding of the physiopathology behind the development of urinary obstruction is vital for correct diagnosis and management.

Background: Acid-base imbalance has been poorly described in patients with coronavirus disease 2019 (COVID-19). Study by the quantitative acid-base approach may be able to account for minor changes in ion distribution that may have been overlooked using traditional acid-base analysis techniques. In a cohort of critically ill COVID-19 patients, we looked for an association between metabolic acidosis surrogates and worse clinical outcomes, such as mortality, renal dialysis, and length of hospital stay.

Aim: To describe the acid-base disorders of critically ill COVID-19 patients using Stewart's approach, associating its variables with poor outcomes.

Methods: This study pertained to a retrospective cohort comprised of adult patients who experienced an intensive care unit stay exceeding 4 days and who were diagnosed with severe acute respiratory syndrome coronavirus 2 infection through a positive polymerase chain reaction analysis of a nasal swab and typical pulmonary involvement observed in chest computed tomography scan. Laboratory and clinical data were obtained from electronic records. Categorical variables were compared using Fisher's exact test. Continuous data were presented as median and interquartile range. The Mann-Whitney U test was used for comparisons.

Results: In total, 211 patients were analyzed. The mortality rate was 13.7%. Overall, 149 patients (70.6%) presented with alkalosis, 28 patients (13.3%) had acidosis, and the remaining 34 patients (16.2%) had a normal arterial pondus hydrogenii. Of those presenting with acidosis, most had a low apparent strong ion difference (SID) (20 patients, 9.5%). Within the group with alkalosis, 128 patients (61.0%) had respiratory origin. The non-survivors were older, had more comorbidities, and had higher Charlson's and simplified acute physiology score 3. We did not find severe acid-base imbalance in this population. The analyzed Stewart's variables (effective SID, apparent SID, and strong ion gap and the effect of albumin, lactate, phosphorus, and chloride) were not different between the groups.

Conclusion: Alkalemia is prevalent in COVID-19 patients. Although we did not find an association between acid-base variables and mortality, the use of Stewart's methodology may provide insights into this severe disease.

Background: Acute kidney injury (AKI) due to interstitial nephritis is a known condition primarily attributed to various medications. While medication-induced interstitial nephritis is common, occurrences due to non-pharmacological factors are rare. This report presents a case of severe AKI triggered by intratubular oxalate crystal deposition, leading to interstitial nephritis. The aim is to outline the case and its management, emphasizing the significance of recognizing uncommon causes of interstitial nephritis.

Case summary: A 71-year-old female presented with stroke-like symptoms, including weakness, speech difficulties, and cognitive impairment. Chronic hypertension had been managed with hydrochlorothiazide (HCTZ) for over two decades. Upon admission, severe hypokalemia and AKI were noted, prompting discontinuation of HCTZ and initiation of prednisolone for acute interstitial nephritis. Further investigations, including kidney biopsy, confirmed severe acute interstitial nephritis with oxalate crystal deposits as the underlying cause. Despite treatment, initial renal function showed minimal improvement. However, with prednisolone therapy and supportive measures, her condition gradually improved, highlighting the importance of comprehensive management.

Conclusion: This case underscores the importance of a thorough diagnostic approach in identifying and addressing uncommon causes of interstitial nephritis. The occurrence of interstitial nephritis due to oxalate crystal deposition, especially without typical risk factors, emphasizes the need for vigilance in clinical practice.