Renin–angiotensin–aldosterone system (RAAS) inhibitors are standard care in patients with hypertension, heart failure or chronic kidney disease (CKD). Although we have studied the RAAS for decades, there are still circumstances that remain unclear. In this review, we describe the evolution of the RAAS and pose the question of whether this survival trait is still necessary to humankind in the present age. We elucidate the benefits on cardiovascular health and kidney disease of RAAS inhibition and present promising novel medications. Furthermore, we address why more studies are needed to establish a new standard of care away from generally prescribing ACEi or ARB toward an improved approach to combine drugs tailored to the needs of individual patients.

Increasing potassium intake ameliorates blood pressure (BP) and cardiovascular (CV) prognoses in the general population; therefore the World Health Organization recommends a high-potassium diet (90–120 mEq/day). Hyperkalaemia is a rare condition in healthy individuals due to the ability of the kidneys to effectively excrete dietary potassium load in urine, while an increase in serum K⁺ is prevalent in patients with chronic kidney disease (CKD). Hyperkalaemia prevalence increases in more advanced CKD stages, and is associated with a poor prognosis. This scenario generates controversy on the correct nutritional approach to hyperkalaemia in CKD patients, considering the unproven link between potassium intake and serum K⁺ levels. Another concern is that drug-induced hyperkalaemia leads to the down-titration or withdrawal of renin-angiotensin system inhibitors (RASI) and mineralocorticoids receptors antagonists (MRA) in patients with CKD, depriving these patients of central therapeutic interventions aimed at delaying CKD progression and decreasing CV mortality. The new K⁺-binder drugs (Patiromer and Sodium-Zirconium Cyclosilicate) have proven to be adequate and safe therapeutic options to control serum K⁺ in CKD patients, enabling RASI and MRA therapy, and possibly, a more liberal intake of fruit and vegetables.

Introduction. Iron deficiency is common in patients with non-dialysis-dependent chronic kidney disease (NDD-CKD). Oral iron supplementation is recommended in these patients, but it is associated with a higher incidence of gastrointestinal adverse reactions. Liposomal iron therapy has been proposed as a new iron formulation, improving iron bioavailability with less side effects; however, few data are available in patients with NDD-CKD. Methods. We designed a single-arm pilot study to evaluate the efficacy of liposomal iron administered for six months in correcting iron deficiency (defined as serum ferritin < 100 ng/mL and/or transferrin saturation < 20%) in patients with NDD-CKD stages 1–5. The primary endpoints were the achievement of serum ferritin ≥ 100 ng/mL and transferrin saturation ≥ 20%. Secondary outcomes were hemoglobin (Hb) changes and the safety of liposomal iron. Results. The efficacy population included 34/38 patients, who completed at least one visit after baseline. Liposomal iron increased the achievement of transferrin saturation targets from 11.8% at baseline to 50.0% at month 6 (p = 0.002), while no significant correction of serum ferritin (p = 0.214) and Hb was found (p = 0.465). When patients were stratified by anemia (Hb < 12 g/dL in women and Hb < 13 g/dL in men), a significant improvement of transferrin saturation was observed only in anemic patients (from 13.3 ± 5.8% to 20.2 ± 8.1%, p = 0.012). Hb values slightly increased at month 6 only in anemic patients (+0.60 g/dL, 95%CI −0.27 to +1.48), but not in those without anemia (+0.08 g/dL, 95%CI −0.73 to +0.88). In patients taking at least one dose of liposomal iron (safety population, n = 38), the study drug was discontinued in eight patients due to death (n = 2), a switch to intravenous iron (n = 2), and the occurrence of side effects (n = 4). Conclusions. The use of liposomal iron in patients with NDD-CKD is associated with a partial correction of transferrin saturation, with no significant effect on iron storage and Hb levels.

Nephrology is an ever-evolving field of medicine. The importance of such a discipline is related to the high clinical impact of kidney disease. In fact, abnormalities of kidney function and/or structure are common in the general population, reaching an overall prevalence of about 10%. More importantly, the onset of kidney damage is related to a strikingly high risk of cardiovascular events, mortality, and progression to kidney failure which, in turn, compromises quality and duration of life. Attempts to comprehend the pathogenesis and molecular mechanisms involved in kidney disease occurrence have prompted the development and implementation of novel drugs in clinical practice with the aim of treating the ‘specific cause’ of kidney disease (including chronic kidney disease, glomerular disease, and genetic kidney disorders) and the main immunological complications following kidney transplantation. Herein, we provide an overview of the principal emerging drug classes with proved efficacy in the context of the aforementioned clinical conditions. This can represent a simplified guide for clinical nephrologists to remind them of the vast and heterogeneous armamentarium of drugs that should be used in the present and the future to improve the management of patients suffering from kidney disease.

Chronic kidney disease (CKD) is a widespread condition with significant cardiovascular risks and a progression to end-stage kidney failure. In recent years, increasing attention has been paid to the role of dietary interventions as a factor capable of influencing disease trajectory. This review summarizes the current observational and interventional evidence on various dietary approaches in patients with CKD and kidney transplants (KTs), including Mediterranean, plant-based, and low-protein diets. A balanced Mediterranean diet, rich in fruits, vegetables, whole grains, fish, and unsaturated fats, shows promises in improving the prognosis for CKD patients. Plant-based diets, which emphasize legumes, vegetables, and grains while minimizing animal protein, improve blood pressure and the glycemic and lipid control. Low-protein diets (LPDs), typically providing less than 0.6 g/kg/day of protein, may reduce the CKD progression and nitrogen burden, further delaying the initiation of dialysis. In conclusion, diets represent a valuable and underutilized therapeutic strategy in the management of CKD and KTs, influencing disease progression and patient outcomes.

The prevalence of recovery of kidney function (RKF) in patients under maintenance dialysis is poorly defined mainly because of different definitions of RKF. Therefore, to gain more insights into the epidemiology of RKF, we performed a systematic review and meta-analysis of studies addressing the prevalence of sustained (at least for 30 days) RKF in patients under maintenance dialysis. Acute kidney injury (AKI) and RKF in the first 90 days of dialysis were the main exclusion criteria. Overall, 7 studies (10 cohorts) including 2,444,943 chronic dialysis patients (range: 430–1,900,595 patients) were meta-analyzed. The period of observation ranged from 4 to 43 years. The prevalence of RKF was 1.49% (95% C.I.:1.05–2.11; p < 0.001] with high heterogeneity I2: 99.8%, p < 0.001. The weighted mean dialysis vintage before RKF was 294 ± 165 days; RKF persisted for a weighted mean of 27.5 months. The percentage of RKF was higher in studies from the U.S. (1.96% [95% C.I.: 1.24–3.07]) as compared to other countries (1.04% [95%C.I.: 0.66–1.62]; p = 0.049). In conclusion, sustained RKF unrelated to AKI occurs in about 1.5% of patients under maintenance dialysis. On average, RKF patients discontinue chronic dialysis about ten months after starting treatment and live free of dialysis for more than two years. The higher prevalence of RKF reported in the U.S. versus other countries suggests a major role of country-specific policies for dialysis start.