Complications métaboliques en insuffisance rénale chronique : hyperphosphatémie, hyperkaliémie et anémie

AI-Powered Renal Diet Support: Performance of ChatGPT, Bard AI, and Bing Chat

Patients with chronic kidney disease (CKD) necessitate specialized renal diets to prevent complications such as hyperkalemia and hyperphosphatemia. A comprehensive assessment of food components is pivotal, yet burdensome for healthcare providers. With evolving artificial intelligence (AI) technology, models such as ChatGPT, Bard AI, and Bing Chat can be instrumental in educating patients and assisting professionals. To gauge the efficacy of different AI models in discerning potassium and phosphorus content in foods, four AI models-ChatGPT 3.5, ChatGPT 4, Bard AI, and Bing Chat-were evaluated. A total of 240 food items, curated from the Mayo Clinic Renal Diet Handbook for CKD patients, were input into each model. These items were characterized by their potassium (149 items) and phosphorus (91 items) content. Each model was tasked to categorize the items into high or low potassium and high phosphorus content. The results were juxtaposed with the Mayo Clinic Renal Diet Handbook's recommendations. The concordance between repeated sessions was also evaluated to assess model consistency. Among the models tested, ChatGPT 4 displayed superior performance in identifying potassium content, correctly classifying 81% of the foods. It accurately discerned 60% of low potassium and 99% of high potassium foods. In comparison, ChatGPT 3.5 exhibited a 66% accuracy rate. Bard AI and Bing Chat models had an accuracy rate of 79% and 81%, respectively. Regarding phosphorus content, Bard AI stood out with a flawless 100% accuracy rate. ChatGPT 3.5 and Bing Chat recognized 85% and 89% of the high phosphorus foods correctly, while ChatGPT 4 registered a 77% accuracy rate. Emerging AI models manifest a diverse range of accuracy in discerning potassium and phosphorus content in foods suitable for CKD patients. ChatGPT 4, in particular, showed a marked improvement over its predecessor, especially in detecting potassium content. The Bard AI model exhibited exceptional precision for phosphorus identification. This study underscores the potential of AI models as efficient tools in renal dietary planning, though refinements are warranted for optimal utility.

[Management of iron deficiency in chronic kidney disease: Review and proposed algorithm]

Iron deficiency is very common in chronic kidney disease, even before the dialysis stage. It is an independent factor of morbidity and mortality in patients with non-dialysis chronic kidney disease. During chronic kidney disease, iron deficiency is defined by a transferrin saturation <20% and/or a serum ferritin <100 μg/L. In France, about half of non-dialysis chronic kidney disease patients have absolute iron deficiency (transferrin saturation <20% and serum ferritin <100 μg/L) and/or functional iron deficiency (transferrin saturation <20% and serum ferritin >100 μg/L). Despite this, iron deficiency is usually not investigated. In fact, more than 60% of nephrologists do not assess iron status at least once a year. In addition, iron deficiency is rarely treated: only 12% of patients are prescribed oral or intravenous iron. Early detection and treatment are fundamental and should be systematic. In order to help improve the management of iron deficiency among non-dialysis chronic kidney disease patients, we propose an algorithm that takes into account current recommendations and the most recent data from the literature. Initial blood test requires the measurement of hemoglobin concentration, transferrin saturation and serum ferritin. A transferrin saturation <20% establishes the diagnosis of iron deficiency and the serum ferritin level points towards an absolute or functional deficiency. The combination of both values makes it possible to adapt the treatment, particularly in an inflammatory context where oral iron is not effective.

Therapeutic Effects of Add-On Tenapanor for Hemodialysis Patients with Refractory Hyperphosphatemia

INTRODUCTION

Phosphate binders are used to treat hyperphosphatemia. Some patients have inappropriately controlled serum phosphorus levels, which may occur for many reasons, including a high pill burden and adverse events (AEs). Tenapanor selectively inhibits the passive paracellular transfer of phosphate in the gastrointestinal tract, thereby reducing serum phosphorus levels. This novel mechanism of action may contribute to improved phosphate management. The efficacy and safety of tenapanor have not been evaluated in Japanese patients with high serum phosphorus levels despite treatment with phosphate binders. This study aimed to assess the efficacy and safety of add-on tenapanor therapy for reducing serum phosphorus levels in this population.

METHODS

This multicenter, double-blind, randomized, placebo-controlled trial enrolled patients with refractory hyperphosphatemia undergoing hemodialysis. Patients were randomly assigned in a 1:1 ratio to receive tenapanor or placebo as an add-on to their phosphate binder regimen for 6 weeks. Change in serum phosphorus levels at week 6 (day 43) compared with the baseline value (day 1, week 0) (primary endpoint), achievement of target serum phosphorus levels (serum phosphorus level ≤6.0 or ≤5.5 mg/dL), and safety, based on all AEs and drug-related AEs, were among the outcomes evaluated.

RESULTS

In total, 24 patients were randomly assigned to the placebo group and 23 to the tenapanor group. The mean serum phosphorus level decreased from 7.01 mg/dL on day 1 to 6.69 mg/dL on day 43 in the placebo group and from 6.77 mg/dL on day 1 to 4.67 mg/dL on day 43 in the tenapanor group. In the placebo and tenapanor groups (modified intent-to-treat population), the mean (standard deviation) change in the serum phosphorus level at day 43 (last observation carried forward [LOCF]) was 0.08 (1.52) mg/dL and -1.99 (1.24) mg/dL, respectively, with a between-group difference of -2.07 (95% confidence interval: -2.89, -1.26; p < 0.001). The target achievement rate (serum phosphorus level ≤6.0 mg/dL at week 6 [LOCF]) was 37.5 and 87.0% in the placebo and tenapanor groups, respectively. Diarrhea was the most common drug-related AE, and it occurred in 8.3 and 65.2% of patients in the placebo and tenapanor groups, respectively. No specific AEs were observed with add-on tenapanor or with phosphate binders.

DISCUSSION/CONCLUSION

Therapy with existing phosphate binders and add-on tenapanor resulted in a significant decrease in serum phosphorus level compared with the placebo group in patients with refractory hyperphosphatemia despite treatment with phosphate binders. No new safety signals were raised, and add-on tenapanor was generally well tolerated.

Clinical features of and risk factors for normoalbuminuric diabetic kidney disease in hospitalized patients with type 2 diabetes mellitus: a retrospective cross-sectional study

BACKGROUND

Normoalbuminuric diabetic kidney disease (NADKD) is a newly defined DKD, the clinical features and pathogenesis for which are still being understood. This study aimed to investigate the features and risk factors for NADKD in patients with type 2 diabetes mellitus (T2DM).

METHODS

A retrospective cross-sectional study was conducted. The related clinical and laboratory data of patients with T2DM hospitalized between August 2012 and January 2020 were collected for statistical analysis. We classified the patients with T2DM into four groups on the basis of the presence or absence of albuminuria and reduced estimated glomerular filtration rate (eGFR). Analysis of variance, the Kruskal-Wallis test, and the chi-square test were used to compare the groups. Binary logistic regression analyses with a forward stepwise method were performed to explore the risk factors for renal dysfunction in hospitalized patients with normoalbuminuric T2DM.

RESULTS

Among the 1620 patients evaluated, 500 (30.9%) had DKD, of which 9% had NADKD. The prevalence of stroke, cardiovascular events, carotid plaque, and peripheral arterial disease in NADKD was significantly higher than in a non-DKD control group (normoalbuminuric T2DM patients with eGFR of ≥60 ml/min/1.73 m²). Regression analyses revealed that three significant independent factors were associated with NADKD: age (OR = 1.089, confidence interval [CI] 95% [1.055-1.123], p < 0.001), previous use of renin-angiotensin system inhibitors (RASIs; OR = 2.330, CI 95% [1.212-4.481], p = 0.011), and glycated hemoglobin (HbA1c; OR = 0.839, CI 95% [0.716-0.983], p = 0.03).

CONCLUSIONS

NADKD is mainly associated with macrovascular rather than microvascular complications. NADKD is more common in patients with normoalbuminuric T2DM with older age, previous use of RASIs, and good glycemic control.

Hyperphosphatemia and Chronic Kidney Disease: A Major Daily Concern Both in Adults and in Children

Hyperphosphatemia is common in chronic kidney disease (CKD). Often seen as the "silent killer" because of its dramatic effect on vascular calcifications, hyperphosphatemia explains, at least partly, the onset of the complex mineral and bone disorders associated with CKD (CKD-MBD), together with hypocalcemia and decreased 1-25(OH)₂ vitamin D levels. The impact of CKD-MBD may be immediate with abnormalities of bone and mineral metabolism with secondary hyperparathyroidism and increased FGF23 levels, or delayed with poor growth, bone deformities, fractures, and vascular calcifications, leading to increased morbidity and mortality. The global management of CKD-MBD has been detailed in international guidelines for adults and children, however, with difficulties to obtain an agreement on the ideal PTH targets. The clinical management of hyperphosphatemia is a daily challenge for nephrologists and pediatric nephrologists, notably because of the phosphate overload in occidental diets that is mainly due to the phosphate "hidden" in food additives. The management begins with a dietary restriction of phosphate intake, and is followed by the use of calcium-based and non-calcium-based phosphate binders, and/or the intensification of dialysis. The objective of this review is to provide an overview of the pathophysiology of hyperphosphatemia in CKD, with a focus on its deleterious effects and a description of the clinical management of hyperphosphatemia in a more global setting of CKD-MBD.

Rare diseases of phosphate and calcium metabolism: Crossing glances between nephrology and endocrinology

Rare diseases of phosphate/calcium metabolism correspond to a wide and heterogeneous spectrum of diseases. Recent knowledge in physiology and genetics has made it possible to better characterize them and to propose attractive therapeutic approaches based on the underlying pathophysiology. These diseases are often at the interface between nephrology and endocrinology. In this spirit of a multidisciplinary care, each specialty can bring its own critical point of view and its own specificities to improve patient care. The objective of this manuscript is to "read" with a nephrologist's point of view the main frameworks of diseases of phosphate/calcium metabolism, to illustrate the three crucial messages of nephro-protection sent to endocrinologists. First, calciuria must be interpreted both in absolute value (concentration hypercalciuria) and in ratio (flow hypercalciuria). Second, renal monitoring of therapies inducing hypercalciuria on kidneys with normal renal function (e.g. active vitamin D analogs or teriparatide) should be systematic. Last, hyperphosphatemia, often latent in hypoparathyroidism and pseudo-hypoparathyroidism, should be detected and at least benefit from dietary measures, in the context of Western diets rich in phosphate hidden in food additives.

DAXX mediates high phosphate-induced endothelial cell apoptosis in vitro through activating ERK signaling

BACKGROUD AND PURPOSE

Hyperphosphatemia, which is a high inorganic phosphate (Pi) level in the serum, promotes endothelial cells dysfunction and is associated with cardiovascular diseases in patients with chronic kidney diseases (CKD). However, the underlying mechanism of high Pi-induced endothelia cell apoptosis remains unclear.

METHODS

Human umbilical vein endothelial cells (HUVECs) were treated with normal Pi (1.0 mM) and high Pi (3.0 mM), and then cell apoptosis, abnormal gene expression and potential signaling pathway involvement in simulated hyperphosphatemia were examined using flow cytometry, quantitative PCR (qPCR) and western blot analysis. A two-step 5/6 nephrectomy was carried out to induce CKD and biochemical measurements were taken.

RESULTS

The rat model of CKD revealed that hyperphosphatemia is correlated with an increased death-domain associated protein (DAXX) expression in endothelial cells. In vitro, high Pi increased the mRNA and protein expression level of DAXX in HUVECs, effects that were reversed by additional phosphonoformic acid treatment. Functionally, high Pi resulted in a significantly increased apoptosis in HUVECs, whereas DAXX knockdown markedly repressed high Pi-induced cell apoptosis, indicating that DAXX mediated high Pi-induced endothelial cell apoptosis. High Pi treatment and DAXX overexpression induced the activation of extracellular regulated protein kinases (ERKs), while DAXX knockdown inhibited high Pi-induced ERKs activation. Finally, we demonstrated that DAXX overexpression induced HUVECs apoptosis in the presence of normal Pi, whereas additional treatment with U0126 (a specific ERK inhibitor) reversed that effect.

CONCLUSION

Upregulated DAXX promoted high Pi-induced HUVECs apoptosis by activating ERK signaling and indicated that the DAXX/ERK signaling axis may be served as a potential target for CKD therapy.

Processed and ultra-processed food consumption are related to metabolic markers in hemodialysis subjects

ABSTRACT Objective To investigate the consumption of processed and ultra-processed foods and evaluate its relationship with the nutritional and metabolic status of hemodialysis patients in a single center in Brazil. Methods This cross-sectional study enrolled 73 individuals in hemodialysis (50 men and 23 women, 21-87 years-old). Clinical and lifestyle variables were assessed by a semi-structured questionnaire and dietary data by food frequency questionnaire. Anthropometric and metabolic data are collected from medical records. Results Processed and ultra-processed foods represented 11.0% of daily caloric intake, 53.0% of trans fatty acid, and 12.5% of salt consumed in the study sample. Individuals who had high intake of this food group (≥128.4g/day, median intake) had higher serum phosphorus and pre-dialysis urea values (p=0.038; p=0.013, respectively). Also, individual with higher consumption of processed meat, sausages and ready prepared food had higher pre-dialysis serum urea (p=0.021), while serum potassium was higher among the subjects who consumed more sauces and salt-based seasonings (p=0.002). Conclusion Higher consumption of processed and ultra-processed foods was associated with important biomarkers of metabolic control for hemodialysis subjects, probably due to non-health dietary composition. Nutritional guidelines and intervention strategies must be promoted to reduce consumption of these food-group in thisspecific population.