Does gouty nephropathy exist, and is it more common than we think?

METTL14 downregulates GLUT9 through m6A methylation and attenuates hyperuricemia-induced fibrosis in mouse renal tubular epithelial cells

Hyperuricemia is a known risk factor for chronic kidney disease (CKD) and subsequent renal fibrosis. N6-methyladenosine (m6A) is the most prevalent chemical modification in eukaryotic mRNAs and has been implicated in various diseases. However, its role in hyperuricemic nephropathy (HN) remains unclear. This study investigated the involvement of the methylase METTL14 in HN pathogenesis. Our in vitro and in vivo function experiments demonstrated that METTL14 plays a crucial role in HN. In mouse models of uric acid (UA)-induced renal injury, we detected impaired kidney function, increased renal interstitial fibrosis, and significantly decreased m6A methylation levels in renal tissues. Treatment with benzbromarone, a UA-lowering drug, alleviated renal injury, restored m6A methylation levels, and upregulated METTL14 expression. Cellular experiments showed that METTL14 overexpression attenuated high UA-induced fibrosis in renal tubular epithelial cells. This overexpression significantly decreases the expression of GLUT9, a key protein involved in UA transport, leading to reduced UA reabsorption. Additionally, MeRIP-qPCR and dual-luciferase reporter gene experiments further demonstrated that METTL14 overexpression enhanced Glut9 mRNA m6A methylation modification, accelerating its degradation and decreasing expression levels. Thus, METTL14-mediated RNA m6A modification plays a role in the renal tubular epithelial cell damage induced by high UA, by regulating Glut9 mRNA post-transcriptionally. These findings provide valuable insights for the diagnosis and development of therapeutic drugs for HN.

Advanced Gouty Nephropathy Complicated With Type 1 Renal Tubular Acidosis: A Case Report

This report describes the case of a 53-year-old woman with chronic kidney disease (CKD) exacerbated by a gout flare who presented with renal tubular acidosis (RTA), hypokalemia, and hyperuricemia. Despite outpatient management for gouty nephropathy, the patient experienced progressive hypokalemia, leading to hospitalization. Upon admission, she was diagnosed with type 1 RTA, characterized by metabolic acidosis and severe hypokalemia, refractory to initial potassium supplementation. The patient's medical history included gout, chronic renal failure, and other comorbidities, complicating her condition. Treatment included aggressive potassium replacement and ongoing management of her gout and CKD. Over several hospital days, her potassium levels stabilized, and she was discharged on oral potassium supplements. This case emphasizes the importance of monitoring electrolyte imbalances and managing uric acid levels in patients with chronic gout and kidney disease to prevent complications such as RTA. Comprehensive management strategies, including dietary and pharmacological interventions, are critical to prevent the progression of gouty nephropathy and improve patient outcomes.

Hyperuricemia and its related diseases: mechanisms and advances in therapy

Hyperuricemia, characterized by elevated levels of serum uric acid (SUA), is linked to a spectrum of commodities such as gout, cardiovascular diseases, renal disorders, metabolic syndrome, and diabetes, etc. Significantly impairing the quality of life for those affected, the prevalence of hyperuricemia is an upward trend globally, especially in most developed countries. UA possesses a multifaceted role, such as antioxidant, pro-oxidative, pro-inflammatory, nitric oxide modulating, anti-aging, and immune effects, which are significant in both physiological and pathological contexts. The equilibrium of circulating urate levels hinges on the interplay between production and excretion, a delicate balance orchestrated by urate transporter functions across various epithelial tissues and cell types. While existing research has identified hyperuricemia involvement in numerous biological processes and signaling pathways, the precise mechanisms connecting elevated UA levels to disease etiology remain to be fully elucidated. In addition, the influence of genetic susceptibilities and environmental determinants on hyperuricemia calls for a detailed and nuanced examination. This review compiles data from global epidemiological studies and clinical practices, exploring the physiological processes and the genetic foundations of urate transporters in depth. Furthermore, we uncover the complex mechanisms by which the UA induced inflammation influences metabolic processes in individuals with hyperuricemia and the association with its relative disease, offering a foundation for innovative therapeutic approaches and advanced pharmacological strategies.

Hyperechoic Spots in the Renal Medulla as a Potential Indicator of Early Gouty Nephropathy

INTRODUCTION

The aim of the study was to explore the causes and clinical significance of hyperechoic renal medulla observed by ultrasonography in patients with primary gout.

METHODS

This study included 2,107 patients with primary gout treated in the Gout Clinic of our hospital from 2016 to 2022. The clinical data and biochemical data of these patients were collected and analyzed. According to the presence or absence of punctate hyperechogenicity in the renal medulla on ultrasound examination, the patients were divided into the hyperechoic medulla (HM) and the normal hypoechoic medulla (NM) groups, and the HM group was further divided into the partial HM (P-HM) and fulfilled HM (F-HM) subgroups according to the distribution range of hyperechogenicity.

RESULTS

Among the 2,107 patients with primary gout, 380 had hyperechoic renal medulla on renal ultrasound, including 106 patients with F-HM and 274 with P-HM. There were significant differences in the gout duration, urate arthropathy number, serum urate (SU) level, clinical tophi number, blood urea nitrogen, serum creatinine (sCr), and estimated glomerular filtration rate between the HM and NM groups or between the F-HM and P-HM subgroups (p < 0.05). Multivariate regression analysis showed that the presence of HM was positively correlated with gout duration, urate arthropathy number, gout attack frequency, SU, and sCr. The number of clinical tophi and sCr were closely related to F-HM.

CONCLUSION

Ultrasound examination showed that a high medulla echo in patients with gout was often related to renal function damage. P-HM may be a transitory condition between NM and F-HM in patients with gout.

Associations of serum uric acid with hypertension status, stages, phenotypes and progressions among Chinese middle-aged and elderly

BACKGROUND AND AIMS

No consensus has been reached on the association between serum uric acid (SUA) and hypertension. This study aimed to investigate the associations between SUA and hypertension, including its status, stages, phenotypes and progressions, among middle-aged and older Chinese.

METHODS AND RESULTS

Data were obtained from the China Health and Retirement Longitudinal Study 2011-2015. Binary logistic regression was used to evaluate the association between SUA and hypertension status. Multinomial logistic regression was used to explore the associations of SUA with hypertension stages, phenotypes and hypertension status progressions. Models were adjusted for potential confounders and stratified by sex. A total of 7931 individuals aged ≥45 years were included, with 39.16 % of hypertension. Significant associations were found of SUA with stage2 and above hypertension (quartile 4 [Q4] vs quartile 1 [Q1]: odds ratio 1.78, 95 % confidence interval 1.31-2.42, P < 0.001), and systolic diastolic hypertension (SDH) (Q4 vs Q1: 1.53, 1.14-2.06, P = 0.005). In sex stratification, significant associations were found between SUA and stage2 and above hypertension and SDH only for men. Moreover, higher quartiles of baseline SUA showed increased risks of maintained hypertension from 2011 to 2015 (Q3 vs Q1: 1.23, 1.03-1.48, P = 0.024; Q4 vs Q1: 1.73, 1.43-2.10, P < 0.001).

CONCLUSION

Higher SUA was associated with hypertension and maintained hypertension among Chinese middle-aged and elderly. Sex-specific associations of SUA with hypertension stages and phenotypes were observed. Regular measurement of SUA in clinical practice may indicate hypertension and its progression, particularly among men.

Asymptomatic Hyperuricemia: A Nephro-Rheumatological Perspective

Hyperuricemia (HU) is a common disorder associated with gout, kidney injury, and high cardiovascular risk. However, whether high serum uric acid (sUA) is a causative factor or just comorbidity remains unclear. When asked if asymptomatic hyperuricemic patients need treatment, even artificial intelligence in the form of the GPT chat provides an ambivalent answer and refers us to a healthcare provider. We believe that such discrepancies stem from an incomplete understanding of the role that uric acid (UA) plays inside and outside the cell. With the rapid development of genomics, proteomics, immunology, and novel biomarkers, we are armed with new data to help us better understand the weight of inborn and environmental factors on an individual's UA concentrations. This review sums up the latest progress that has been made in the field of asymptomatic HU, compares the results presented by various research teams, and indicates new directions that emerge for future studies.

Prevalence and clinical association of hyperechoic crystal deposits on ultrasonography in patients with chronic kidney disease: a cross-sectional study from a single center

BACKGROUND

Hyperechoic crystal deposits can be detected in the kidney medulla of patients with gout by ultrasonography examination. Chronic kidney disease (CKD) is usually accompanied with hyperuricemia. Whether hyperechoic crystal deposition could be detected by ultrasonography in CKD patients, and its clinical association are unknown.

METHODS

Five hundred and fifteen consecutive CKD patients were included in this observational study. Clinical, biochemical and pathological data were collected and analyzed.

RESULTS

Altogether, 234 (45.4%) patients were found to have hyperuricemia and 25 patients (4.9%) had gout history. Hyperechoic crystal deposits in kidney medulla were found in forty-four (8.5%) patients, on ultrasonography. Compared with patients without hyperechoic crystal deposits, patients with deposits were more likely to be male, younger, with gout history and presenting with higher serum uric acid level, lower estimated glomerular filtration rate, lower urine pH, lower 24 h-urinary citrate and uric acid excretion, and with a higher percentage of ischemic nephropathy (all p < 0.05). On multivariable logistic analysis, the hyperechoic depositions were associated with age [0.969 (0.944, 0.994), p = 0.016], serum uric acid level [1.246 (1.027, 1.511), p = 0.026], Sqrt-transformed 24 h-urine uric acid excretion [0.923 (0.856, 0.996), p = 0.039], and ischemic nephropathy [4.524 (1.437, 14.239), p = 0.01], respectively.

CONCLUSIONS

Hyperechoic crystal deposition can be detected in kidney medulla by ultrasonography; in CKD patients their presence was associated with hyperuricemia as well as with ischemic nephropathy.

Exploring the Multifaceted Nexus of Uric Acid and Health: A Review of Recent Studies on Diverse Diseases

The prevalence of patients with hyperuricemia or gout is increasing worldwide. Hyperuricemia and gout are primarily attributed to genetic factors, along with lifestyle factors like consuming a purine-rich diet, alcohol and/or fructose intake, and physical activity. While numerous studies have reported various comorbidities linked to hyperuricemia or gout, the range of these associations is extensive. This review article focuses on the relationship between uric acid and thirteen specific domains: transporters, genetic factors, diet, lifestyle, gout, diabetes mellitus, metabolic syndrome, atherosclerosis, hypertension, kidney diseases, cardiovascular diseases, neurological diseases, and malignancies. The present article provides a comprehensive review of recent developments in these areas, compiled by experts from the Young Committee of the Japanese Society of Gout and Uric and Nucleic Acids. The consolidated summary serves to enhance the global comprehension of uric acid-related matters.

Urate-lowering drugs for chronic kidney disease with asymptomatic hyperuricemia and hypertension: a randomized trial

INTRODUCTION

Xanthine oxidase (XO) inhibitors may slow down chronic kidney disease (CKD) progression. The comparative effectiveness of the different urate-lowering drugs is unknown. The aim of this study was to determine whether urate-lowering therapy with an XO inhibitor (febuxostat) and that with a uricosuric drug (benzbromarone) are comparable in slowing renal function decline in patients with CKD complicated with hypertension and hyperuricemia.

METHODS

This study was an open-label randomized parallel-group clinical trial of 95 patients with stage G3 CKD in Japan. The patients had hypertension and hyperuricemia without a history of gout. They were randomized to receive febuxostat ( n  = 47; febuxostat group) or benzbromarone ( n  = 48; benzbromarone group) and titrated to reduce their serum urate level to <6.0 mg/dl. The primary end-point was change in estimated glomerular filtration rate (eGFR) from baseline to 52 weeks. The secondary end-points included changes in uric acid level, blood pressure, urinary albumin-to-creatinine ratio, and XO activity.

RESULTS

Of the 95 patients, 88 (92.6%) completed the trial. There were no significant differences in change in eGFR (in ml/min/1.73 m 2 ) between the febuxostat [-0.23, 95% confidence interval (CI), -2.00 to 1.55] and benzbromarone (-2.18, 95% CI, -3.84 to -0.52) groups (difference, 1.95; 95% CI, -0.48 to 4.38; P  = 0.115) nor in the secondary end-points, except for XO activity. Febuxostat significantly reduced XO activity ( P  = 0.010). There were no significant differences in primary and secondary outcomes between the groups. A decrease in eGFR was significantly less in the febuxostat group than that of the benzbromarone group in the CKDG3a, but not in CKDG3b, in the subgroup analysis. There were no adverse effects specific to either drug.

CONCLUSIONS

No significant differences were found in the effects of febuxostat and benzbromarone in renal function decline in stage G3 CKD complicated with hyperuricemia and hypertension.

High-Fructose Diet-Induced Hyperuricemia Accompanying Metabolic Syndrome-Mechanisms and Dietary Therapy Proposals

Fructose is often used as a food ingredient due to its low production costs and sweetening power. In recent years, it has been noticed that people on a Western diet high in fructose have high levels of uric acid in their blood. It was recognized that the specific metabolism of fructose in the body might cause increased production of uric acid, which then may affect the intensification of lipogenesis and the development of metabolic syndrome (MetS), insulin resistance, gout, cardiovascular diseases, leptin resistance, or non-alcoholic fatty liver disease. So far, to treat hyperuricemia, it has been recommended to use a low-purine diet characterized by limiting protein-containing products. However, this recommendation often leads to an increased intake of carbohydrate-rich foods that may contain fructose. Increased fructose consumption may enhance the secretion of uric acid again and, consequently, does not have therapeutic effects. Therefore, instead of a low-purine diet, using healthy diets, such as DASH or the Mediterranean diet, which can benefit metabolic parameters, could be a better proposal. This article provides an overview of this approach, focusing on MetS and hyperuricemia among high-fructose dieters.

Does uric acid-lowering treatment slow the progression of chronic kidney disease? A meta-analysis of randomized controlled trials

INTRODUCTION

Hyperuricemia has been proposed as an independent factor in the development and progression of chronic kidney disease (CKD). However, the effect of uric acid-lowering therapies on delaying CKD progression is still uncertain. Therefore, this systemic review aims to assess the effect of uric acid-lowering therapies on renal outcomes in pre-dialysis CKD patients.

METHODS

PubMed, Cochrane Library, and Lilacs databases were searched until April 24, 2021, for randomized clinical trials of CKD patients on uric acid-lowering treatment with xanthine-oxidase (XO) inhibitors. The weighted mean difference (WMD) or standard mean difference (SMD) with confidence interval (CI) were pooled using a random-effects model.

RESULTS

Among 567 studies found, eighteen met the inclusion criteria (n=2463 participants). Compared to the patient's control group, the WMD for the glomerular filtration ratio (GFR) and serum creatinine changes of the treated group was 2.02ml/min/1.73m² (95%CI 0.41 to 3.63, P=0.014) and -0.19mg/dl (95%CI -0.34 to -0.04, I²=86.2%, P=0.011), respectively. Subgroup analyses showed that the difference in follow-up time and CKD population type in the studies may explain the controversy about the role of uric acid-lowering therapies in CKD progression. The GFR and creatinine outcomes analysis by types of XO inhibitors showed no difference between the control and treated groups. Uric acid-lowering therapies were strongly associated with decreased serum uric acid and urinary protein-creatinine ratio and urinary albumin-creatinine ratio.

CONCLUSIONS

These findings suggest that uric acid-lowering treatment may slow CKD progress and reduce protein and albumin excretion. However, larger and properly powered randomized clinical trials with specific CKD populations are needed to confirm these findings.

Insoluble Fiber in Barley Leaf Attenuates Hyperuricemic Nephropathy by Modulating Gut Microbiota and Short-Chain Fatty Acids

Hyperuricemia (HUA), characterized by abnormal serum uric acid (UA) levels, is recognized as an important risk factor for hyperuricemic nephropathy (HN), which is strongly linked to gut microbiota. This study investigated the protective effects and regulatory mechanisms of insoluble fiber from barley leaves (BL) against HN, induced by adenine (Ad) and potassium oxonate (PO). The results showed that BL dramatically reduced the levels of serum UA and creatinine (CR) and alleviated renal injury and fibrosis. Moreover, BL modulated oxidative stress and downregulated the expression of urate transporter 1 (URAT1) and glucose transporter 9 (GLUT9) in the kidneys of mice with HN. In addition, the 16S rRNA sequence data showed that BL also increased the relative abundance of short-chain fatty acids (SCFAs)-producing bacteria, including Bacteroides, Alloprevotella, and Eisenbergiella. Besides, BL treatment also increased SCFAs levels. Of interest, the application of SCFAs in hyperuricemic mice effectively reduced their serum UA. Furthermore, SCFAs dose-dependently inhibited URAT1 and GLUT9 in vitro and potently interacted with URAT1 and GLUT9 in the docking analysis. When taken together, our results indicate that BL and its metabolite SCFAs may be potential candidates for relieving HUA or HN.

Chronic kidney disease: Which role for xanthine oxidoreductase activity and products?

The present review explores the role of xanthine oxidoreductase (XOR) in the development and progression of chronic kidney disease (CKD). Human XOR is a multi-level regulated enzyme, which has many physiological functions, but that is also implicated in several pathological processes. The main XOR activities are the purine catabolism, which generates uric acid, and the regulation of cell redox state and cell signaling, through the production of reactive oxygen species. XOR dysregulation may lead to hyperuricemia and oxidative stress, which could have a pathogenic role in the initial phases of CKD, by promoting cell injury, hypertension, chronic inflammation and metabolic derangements. Hypertension is common in CKD patients and many mechanisms inducing it (upregulation of renin-angiotensin-aldosterone system, endothelial dysfunction and atherosclerosis) may be influenced by XOR products. High XOR activity and hyperuricemia are also risk factors for obesity, insulin resistance, type 2 diabetes and metabolic syndrome that are frequent CKD causes. Moreover, CKD is common in patients with gout, which is characterized by hyperuricemia, and in patients with cardiovascular diseases, which are associated with hypertension, endothelial dysfunction and atherosclerosis. Although hyperuricemia is undoubtedly related to CKD, controversial findings have been hitherto reported in patients treated with urate-lowering therapies.

Efficacy and Safety of Qinpi Tongfeng Formula in the Treatment of Acute Gouty Arthritis: A Double-Blind, Double-Dummy, Multicenter, Randomized Controlled Trial

Objective

Traditional Chinese medicine (TCM) has certain curative effect against acute gouty arthritis (AGA), but it lacks high-quality evidence-based studies. In this randomized controlled trial, we try to evaluate the clinical efficacy and safety of Qinpi Tongfeng Formula (QPTFF) in the treatment of AGA.

Methods

One hundred and fourteen patients with AGA (damp heat accumulation syndrome) who met the inclusion and exclusion criteria were randomly divided into treatment group and control group in a ratio of 1 : 1. Patients in the treatment group were treated with QPTFF, and patients in the control group were treated with diclofenac sodium sustained-release tablets for 7 days. The primary outcome measure was the change in visual analog scale (VAS) score for pain from the baseline to day 8. The secondary outcome measures were joint symptom score, TCM syndrome score, total effective rate, pain cure rate, complete pain relief time, patient satisfaction score, erythrocyte sedimentation rate (ESR), C-reactive protein (CRP), and serum uric acid level. The safety outcome measures were routine blood test, urinalysis, liver function including alanine aminotransferase and aspartate aminotransferase, renal function including blood urea nitrogen and serum creatinine, and the rate of treatment-related adverse events (TRAEs).

Results

105 patients with 53 in the treatment group and 52 in the control group completed the 7-day treatment. There was no significant difference between two groups in demographic characteristics, VAS score for pain, joint symptom score, TCM syndrome score, ESR, CRP, and serum uric acid level before enrollment at baseline (based on both the full analysis set (FAS) and per protocol set (PPS), P > 0.05). The 95% confidence interval of the difference between the eighth and first VAS score for pain of the two groups was (−0.57, 0.42) in FAS and (−0.48, 0.47) in PPS. The lower bound of both FAS and PPS is greater than the bound value of −0.7. On day 8, there was no significant difference between the two groups in joint symptom score, TCM syndrome score, total effective rate, pain cure rate, complete pain relief time, patient satisfaction score, ESR, and CRP (FAS and PPS, P > 0.05). The serum uric acid level and TRAEs in the treatment group were significantly lower than those in the control group (FAS and PPS, P < 0.05).

Conclusions

QPTFF could alleviate the symptoms of patients with AGA, which is not inferior to diclofenac sodium sustained-release tablets in analgesic. Moreover, QPTFF overmatches diclofenac sodium sustained-release tablets in decreasing serum uric acid level and TRAEs. Therefore, the results provide reliable foundation for QPTTF in the treatment of AGA. Trial Registration. This study protocol was registered in Chinese Clinical Trial Registry (registration number: ChiCTR2100050638).

Prevalence and Outcomes Associated with Hyperuricemia in Hospitalized Patients with COVID-19

INTRODUCTION

Coronavirus 2019 (COVID-19) can increase catabolism and result in hyperuricemia. Uric acid (UA) potentially causes kidney damage by alteration of renal autoregulation, inhibition of endothelial cell proliferation, cell apoptosis, activation of the pro-inflammatory cascade, and crystal deposition. Hyperuricemia in patients with COVID-19 may contribute to acute kidney injury (AKI) and poor outcomes.

METHODS

We included 834 patients with COVID-19 who were >18 years old and hospitalized for >24 h in the Mount Sinai Health System and had at least 1 measurement of serum UA. We examined the association between the first serum UA level and development of acute kidney injury (AKI, defined by KDIGO criteria), major adverse kidney events (MAKE, defined by a composite of all-cause in-hospital mortality or dialysis or 100% increase in serum creatinine from baseline), as well as markers of inflammation and cardiac injury.

RESULTS

Among the 834 patients, the median age was 66 years, 42% were women, and the median first serum UA was 5.9 mg/dL (interquartile range 4.5-8.8). Overall, 60% experienced AKI, 52% experienced MAKE, and 32% died during hospitalization. After adjusting for demographics, comorbidities, and laboratory values, a doubling in serum UA was associated with increased AKI (odds ratio [OR] 2.8, 95% confidence interval [CI] 1.9-4.1), MAKE (OR 2.5, 95% CI 1.7-3.5), and in-hospital mortality (OR 1.7, 95% CI 1.3-2.3). Higher serum UA levels were independently associated with a higher level of procalcitonin (β, 0.6; SE 0.2) and troponin I (β, 1.2; SE 0.2) but were not associated with serum ferritin, C-reactive protein, and interleukin-6.

CONCLUSION

In patients admitted to the hospital for COVID-19, higher serum UA levels were independently associated with AKI, MAKE, and in-hospital mortality in a dose-dependent manner. In addition, hyperuricemia was associated with higher procalcitonin and troponin I levels.

Serum Uric Acid Is a Weak Independent Predictor of Overall Survival in Older Adults

Hyperuricemia accompanies many pathologies that contribute to overall death rate. The population-based multifaceted study of older adults in Poland made it possible to assess the effect of serum uric acid (SUA) on overall mortality. The PolSenior study performed between 2007-2011 included 3926 participants aged 65 years or above (mean age 79 ± 9 years) not treated with xanthin oxidase inhibitors (XOI) who were stratified by sex and SUA concentration into six subgroups increasing by 1 mg/dL. In 2019, survival data were retrieved from the population register. The crude risk of death was significantly higher in men and women with SUA ≥ 7 mg/dL. After adjustment to statistically significant factors, SUA remained a risk factor of death in men with SUA ≥ 8 mg/dL only, potentially due to the limited number of women with high SUA levels. Furthermore, age, heart failure, diabetes, and activities of daily living ≤ 4 pts were identified as factors increasing mortality risk regardless of sex. The risk of death increased also with smoking, past stroke, COPD/asthma, and hs-CRP > 3 mg/dL for men; and eGFR < 45 mL/min/1.73 m2, mini nutritional assessment ≤ 7 pts, and loop diuretics use for women. Mild hyperuricemia is a significant health status marker and an independent risk factor for overall mortality in older Caucasians not receiving XOI. Increased mortality is mostly limited to subjects with SUA levels ≥ 8 mg/dL.

From classical to innovative clinical epidemiology: the 50 years' experience of the Brisighella Heart Study

INTRODUCTION

The Brisighella Heart Study (BHS) is a long-term, prospective, population-based longitudinal study on 2939 randomly selected residents of the town of Brisighella, Emilia-Romagna, Italy.

EVIDENCE ACQUISITION

At the enrollment time in 1972 no participant had any cardiovascular disease, 1491 participants were men and 1448 women, and the age span was 14 to 84 years.

EVIDENCE SYNTHESIS

The observational phase of the study contributed to the evidence of a strong pathophysiological association between hypercholesterolemia and hypertension. The interventional phase was one of the first examples of successful cardiovascular risk reduction obtained through a population-based educational intervention. Currently, the BHS staff is planning its 11th four-yearly population survey in 2022. Today, the study is moving from an epidemiological perspective to a translational approach, involving advanced biomolecular analyses, genetic tests, and functional vascular investigations.

CONCLUSIONS

This review aims to summarize the main findings of the first 50 years of BHS research and spot the latest developments and future perspectives of this remarkable Italian cardiovascular study.

Hyperuricemia and chronic kidney disease: to treat or not to treat

Hyperuricemia is common in chronic kidney disease (CKD) and may be present in 50% of patients presenting for dialysis. Hyperuricemia can be secondary to impaired glomerular filtration rate (GFR) that occurs in CKD. However, hyperuricemia can also precede the development of kidney disease and predict incident CKD. Experimental studies of hyperuricemic models have found that both soluble and crystalline uric acid can cause significant kidney damage, characterized by ischemia, tubulointerstitial fibrosis, and inflammation. However, most Mendelian randomization studies failed to demonstrate a causal relationship between uric acid and CKD, and clinical trials have had variable results. Here we suggest potential explanations for the negative clinical and genetic findings, including the role of crystalline uric acid, intracellular uric acid, and xanthine oxidase activity in uric acid-mediated kidney injury. We propose future clinical trials as well as an algorithm for treatment of hyperuricemia in patients with CKD.

Uric Acid and Hypertension: Prognostic Role and Guide for Treatment

The relationship between serum uric acid (SUA) and hypertension has been a subject of increasing interest since the 1870 discovery by Frederick Akbar Mahomed. Several epidemiological studies have shown a strong association between high SUA levels and the presence or the development of hypertension. Genetic analyses have found that xanthine oxidoreductase (XOR) genetic polymorphisms are associated with hypertension. However, genetic studies on urate transporters and Mendelian randomization studies failed to demonstrate a causal relationship between SUA and hypertension. Results from clinical trials on the role of urate-lowering therapy in the management of patients with hypertension are not uniform. Our study sought to analyze the prognostic and therapeutic role of SUA in the hypertensive disease, from uric acid (UA) biology to clinical trials on urate-lowering therapies.

Acute Kidney Injury in Pediatric Diabetic Kidney Disease

Diabetic kidney disease (DKD) is a common complication of type 1 and 2 diabetes and often presents during adolescence and young adulthood. Given the growing incidence of both type 1 and type 2 diabetes in children and adolescents, DKD represents a significant public health problem. Acute kidney injury (AKI) in youth with diabetes is strongly associated with risk of DKD development. This review will summarize the epidemiology and pathophysiology of AKI in children with diabetes, the relationship between AKI and DKD, and the potential therapeutic interventions. Finally, we will appraise the impact of the recent COVID-19 infection pandemic on AKI in children with diabetes.