[Consensus document for the detection and management of chronic kidney disease]

Is the use of the new Chronic Kidney Disease Epidemiology Consortium (CKD-EPI 2021) formula appropriate for the Spanish population?

INTRODUCTION

United States nephrology societies recommend changing from the CKD-EPI 2009 equation to the new CKD-EPI 2021 equation, which does not include the race coefficient, for calculating estimated glomerular filtration rate (eGFR). It is unknown how this change might affect the distribution of kidney disease in the predominantly Caucasian Spanish population.

METHODS

Two databases of adults from the province of Cádiz, DB-SIDICA (N=264,217) and DB-PANDEMIA (N=64,217), that had plasma creatinine measurements recorded between 2017 and 2021 were studied. Changes in eGFR and the consequent reclassification into different categories of the KDIGO 2012 classification resulting from substituting the CKD-EPI 2009 equation for the 2021 equation were calculated.

RESULTS

Compared to the 2009 equation, CKD-EPI 2021 yielded a higher eGFR, with a median of 3.8mL/min/1.73m² (IQR 2.98-4.48) in DB-SIDICA and 3.89mL/min/1.73m² (IQR 3.05-4.55) in DB-PANDEMIA. The first consequence was that 15.3% of the total population in DB-SIDICA and 15.1% of the total population in DB-PANDEMIA were reclassified into a higher category of eGFR, as were 28.1% and 27.3%, respectively, of the population with CKD (G3-G5); no subjects were classified into the more severe category. The second consequence was that the prevalence of kidney disease decreased from 9% to 7.5% in both cohorts.

CONCLUSIONS

Implementing the CKD-EPI 2021 equation in the Spanish population, which is predominantly Caucasian, would increase eGFR by a modest amount (greater in men and those who are older or have a higher GFR). A significant proportion of the population would be classified into a higher eGFR category, with a consequent decrease in the prevalence of kidney disease.

Kidney Disease in Diabetic Patients: From Pathophysiology to Pharmacological Aspects with a Focus on Therapeutic Inertia

Diabetes mellitus represents a growing concern, both for public economy and global health. In fact, it can lead to insidious macrovascular and microvascular complications, impacting negatively on patients' quality of life. Diabetic patients often present diabetic kidney disease (DKD), a burdensome complication that can be silent for years. The average time of onset of kidney impairment in diabetic patients is about 7-10 years. The clinical impact of DKD is dangerous not only for the risk of progression to end-stage renal disease and therefore to renal replacement therapies, but also because of the associated increase in cardiovascular events. An early recognition of risk factors for DKD progression can be decisive in decreasing morbidity and mortality. DKD presents patient-related, clinician-related, and system-related issues. All these problems are translated into therapeutic inertia, which is defined as the failure to initiate or intensify therapy on time according to evidence-based clinical guidelines. Therapeutic inertia can be resolved by a multidisciplinary pool of healthcare experts. The timing of intensification of treatment, the transition to the best therapy, and dietetic strategies must be provided by a multidisciplinary team, driving the patients to the glycemic target and delaying or overcoming DKD-related complications. A timely nephrological evaluation can also guarantee adequate information to choose the right renal replacement therapy at the right time in case of renal impairment progression.

Impaired Reconversion of Bone Marrow in Nuclear Magnetic Resonance in Patients with Chronic Renal Disease

BACKGROUND

Anemia is one of the main consequences of Chronic Kidney Disease (CKD), which causes a bone marrow response determined by Magnetic Resonance Imaging.

OBJECTIVE

The objective of this study was to identify Bone Marrow Reconversion (BMR) by nuclear magnetic resonance imaging in patients with CKD.

METHODS

A descriptive study was carried in "José Carrasco Arteaga" Hospital, Cuenca-Ecuador. Images of the femurs of patients diagnosed with CKD were acquired by magnetic resonance imaging. Several variables, including age, sex, CKD stage, anemia and BMR, were taken into account. Groups are analyzed according to the stages CKD with the Anova test and logistic regression is obtained for the BMR event with the study variables.

RESULTS

Two hundred sixteen patients were included in this analysis. Prevalences of Anemia were 2/40 (5%) in Group 1, 3/35 (8.6%) in group 2, 17/56 (30.4%) in group 3, 23/46 (50%) in group 4 and 25/39 (64.1%) in group 5, Anova P<0.0001. BMR in Group 1 was 12 cases (30%), in group 2: 4 cases (11.4%), in group 3: 18 cases (32.1%), in group 4: 13 cases (28.3%), and group 5: 17 cases (43.6%). P=0.51. Regression equation for BMR were significant with sex (male) OR 0.193 (CI95% 0.092-0.405) P<0.0001, CKD Stage 1 OR 0.195 (0.057-0.668) P=0.009, Stage 2 OR 0.082 (0.020-0.329). Other variables were not significant.

CONCLUSION

In this study, we describe that there is an impaired Reconversion of Bone Marrow in Nuclear Magnetic Resonance Imaging in Patients with Chronic Renal Disease in stages 3, 4 and 5, despite the progressive presence of anemia. The female sex is associated with the presence of bone marrow reconversion. No statistical dependence was observed between anemia and the reconversion of bone marrow.

[Concordance between the equations "Chronic Kidney Disease Epidemiological Collaboration" and "Modification of Diet in Renal Disease" with the "Berlin Initiative Study" to estimate renal function in the elderly]

OBJECTIVE

Estimated glomerular filtration rate (eGFR) is calculated routinely using creatinine-based formulas, but their reliability in the elderly is limited. The aim of this study was to analyse the concordance between the BIS1 equation which is specific for the elderly, and the usual CKD-EPI and MDRD-IDMS in a large population over 70 years of age.

MATERIAL AND METHODS

Retrospective cross-sectional study in which the eGFR was calculated using BIS1, CKD-EPI and MDRD-IDMS equations based on gender, age, and creatinine data of 85,089 subjects (58.5% women, mean age 78 years [IQR 73-83]).The following statistics were carried out: Wilcoxon test, Bland-Altman graphic analysis, study of the concordance using the intraclass correlation coefficient (ICC), and comparison tables for the classification of CKD.

RESULTS

The median of the eGFRs using BIS1 was 58mL/min/1.73m² (IQR 48-70), using CKD-EPI was 68mL/min/1.73m² (IQR 53-84), and using MDRD it was 68mL/min/1.73m² (IQR 53-82). The concordance between BIS1 and CKD-EPI (intraclass correlation coefficient =0.87) was found to be acceptable. It was lower with MDRD (intraclass correlation coefficient =0.81). A mean difference of 8mL/min/1.73m² (SD 2.6-18) was found BIS1 vs. CKD-EPI, and 10mL/min/1.73m² (SD 6-27) with BIS1 vs. MDRD, which was maintained when stratifying by gender and age groups.

CONCLUSIONS

Despite the acceptable statistical agreement, the eGFR obtained with the BIS1 equation is not interchangeable with CKD-EPI or with MDRD-IDMS. The BIS1 equation gives lower values than CKD-EPI, and classifies patients into a higher level of CKD, mainly when the eGFR is above 30mL/min/1.73 m².

Altered gut microbiome promotes proteinuria in mice induced by Adriamycin

Inflammation has recently been attributed to dysbiosis of the gut microbiome, which has been linked to proteinuria in chronic kidney disease. Since Adriamycin® (ADR) is widely used to induce proteinuria in mouse models, the aim of this study was to explore the potential effect of gut microbiome on this process. Both ADR resistant (C57BL/6) and susceptible (BALB/C) strains were part of the induced nephropathy with ADR injection. BALB/C mice significantly presented increased urinary albumin/creatinine ratio (UACR) with renal lesions in pathology, but C57BL/6 mice were absent from kidney damage. Species and genus level resolution analysis showed a shift in gut microbial profile between BALB/C and C57BL/6 mice. ADR further altered the stool microbiome in BALB/C mice, particularly with enrichment of Odoribacter and depletion of Turicibacter, Marvinbryantia and Rikenella. Moreover, the level of UACR in BALB/C mice was marked related to the abundance of Marvinbryantia, Odoribacter and Turicibacter in stool. Meanwhile, ADR remarkably increased the serum levels of interleukin (IL)-2 in BALB/C mice, but not in C57BL/6 mice. It is suggested that the favorably altered stools as shown in the microbiome might promote the inflammation and proteinuria in ADR-sensitive mice, which provides a new insight on the pathogenicity of chronic kidney disease.