Low-Protein Diet in Elderly Patients with Chronic Kidney Disease Stage 4 and 5 in Conservative Management: Focus on Sarcopenia Development

INTRODUCTION

Chronic kidney disease is a degenerative and increasingly prevalent condition that includes metabolic abnormalities and is associated with a higher risk of sarcopenia. The conservative approach points primarily to controlling metabolic issues and reducing the risk of malnutrition and sarcopenia, slowing the progression of kidney disease. The present study aims to evaluate the effect of a low-protein diet on malnutrition and sarcopenia.

METHODS

A total of 45 patients (33 male and 12 female) aged over 70 with chronic kidney disease stage 4-5 in conservative management were considered. All patients had a dietary assessment and prescription of personalized low-protein dietary plans (≤0.6 g protein/kg) and a follow-up control between 4 and 6 months. In preliminary and follow-up evaluations, anthropometric data, blood examinations, body composition results, muscle strength, physical performance, and a 3-day food diary were collected.

RESULTS

In the follow-up period, a significant weight loss (p = 0.001) and a decrease in body mass index (p = 0.002) were recorded. Food diaries revealed a significant reduction in protein, sodium, potassium, and phosphorus intake (p < 0.001), with a significant reduction in urea (p < 0.001) and proteinuria (p = 0.01) without any impact on lean mass (p = 0.66). Considerable variations in adherence between food diaries and the prescribed diet were also noted.

CONCLUSIONS

Providing a personalized low-protein diet led to significant benefits in a short period without worsening the patient's nutritional status.

"Every Cloud Has a Silver Lining": How Three Rare Diseases Defend Themselves from COVID-19 and What We Have Learnt from It

The process of SARS-CoV-2 infection, responsible for the COVID-19 pandemic, is carried out through different steps, with the interaction between ACE2 and Spike protein (S) being crucial. Besides of that, the acidic environment of endosomes seems to play a relevant role in the virus uptake into cells and its intracellular replication. Patients affected by two rare genetic tubulopathies, Gitelman's and Bartter's Syndromes, and a rare genetic metabolic disease, Fabry Disease, have shown intrinsic protection from SARS-CoV-2 infection and COVID-19 on account of specific intrinsic features that interfere with the virus uptake into cells and its intracellular replication, which will be reported and discussed in this paper, providing interesting insights for present and future research.

EBV Reactivation in Transplant Recipients following SARS-CoV-2 Infection: A Retrospective Study

Reactivation and primary infection with a high Epstein Barr Virus (EBV) DNA level in kidney transplant patients could cause severe complications, including the development of Post-Transplantation Lymphoproliferative Disease (PTLD). While in the general population the reactivation of EBV after SARS-CoV-2 infection has been reported, very few data are available in transplant recipients. Our retrospective study aimed to evaluate a possible EBV reactivation in kidney transplant patients following SARS-CoV-2 infection and a possible impairment of the immune system. In addition, the effects of changes in immunosuppressive therapy on EBV DNA reactivation and vaccination were also evaluated. A total of 166 kidney transplant patients followed at the Kidney-Pancreas Transplant Ambulatory Nephrology Unit at Padova University Hospital were retrospectively considered for an observation period of 6 months from January 2020 to April 2023. EBV DNA level was measured by Rt-PCR and evaluated 6 months before and after SARS-CoV-2 infection. Patients' serological states were established via quantification of anti-VCA and anti-EBNA (chemiluminescence). Patients' immune systems were characterized by CD4+/CD8+ lymphocyte ratio (flow cytometry). EBV DNA was reactivated in 50% of the 166 patients with COVID-19 who completed the study. Older patients with more severe forms of COVID-19 had higher EBV reactivation (p < 0.05). EBV reactivation significantly increased in patients with severe SARS-CoV-2 infection requiring hospitalization compared to patients managed at home (p < 0.001). CD4+/CD8+ lymphocyte ratio was reduced in patients with a younger age of transplant (p < 0.01) and on a higher dose of steroids (p < 0.01). The results of our study confirm the role of immunodepression, especially in recent transplant patients and those on high steroids, in EBV reactivation. These results combined with the few available in the literature might contribute to providing an optimal management of immunosuppressive treatment for these patients in order to obtain an immune state unfavorable to the activation of latent viruses, including EBV.

The RAAS Goodfellas in Cardiovascular System

In the last two decades, the study of the renin-angiotensin-aldosterone system (RAAS) has revealed a counterregulatory protective axis. This protective arm is characterized by ACE2/Ang 1-7/MasR and Ang 1-9 that largely counteracts the classic arm of the RAAS mediated by ACE/Ang II/AT1R/aldosterone and plays an important role in the prevention of inflammation, oxidative stress, hypertension, and cardiovascular remodeling. A growing body of evidence suggests that enhancement of this counterregulatory arm of RAAS represents an important therapeutic approach to facing cardiovascular comorbidities. In this review, we provide an overview of the beneficial effects of ACE2, Ang 1-7/MasR, and Ang 1-9 in the context of oxidative stress, vascular dysfunction, and organ damage.

Safety of Citrate Anticoagulation in CKRT: Monocentric Experience of a Dynamic Protocol of Calcium Monitoring

Regional Citrate Anticoagulation (RCA) is considered the first-line anticoagulation for Continuous Kidney Replacement Therapy (CKRT). The RCA requires strict protocols and trained staff to avoid unsafe use and ensure its benefit. We have analyzed all our CKRT prescriptions from December 2020 to April 2022 anonymously, collecting data on CKRT, lab tests, clinical conditions, and complications of RCA. In addition, in order to better detect citrate accumulation, we have performed an RCA protocol by reducing the CaTot/Ca2+ ratio cut-off from 2.50 to 2.40 and increasing the number of calcium checks according to its trend. Among the 374 patients in CKRT, 104 received RCA prescriptions, of which 11 (10.6%) were discontinued: 4 for the suspicion of citrate accumulation, 1 for the development of metabolic alkalosis, 1 for the shift to a different CKRT procedure due to the need for a higher bicarbonate dose, 4 for the elevation of hepatocytolysis indexes, and 1 due to a preemptive discontinuation following massive post-surgery bleeding. None of the patients have had citrate toxicity as indicated by a CaTot/Ca2+ greater than 2.50, and our protocol has allowed the early identification of patients who might develop clinical citrate toxicity.

Oxidants and Cardiorenal Vascular Remodeling—Insights from Rare Genetic Tubulopathies: Bartter’s and Gitelman’s Syndromes

Two human genetic tubulopathies, Bartter’s (BS) and Gitelman’s (GS) syndromes, have normo/hypotension and absent cardiac remodeling despite their apparent angiotensin system (RAS) activation. This seeming contradiction has led to an extensive investigation of BSGS patients, the result of which is that BSGS represents a mirror image of hypertension. BSGS’s unique set of properties has then permitted their use as a human model to probe and characterize RAS system pathways and oxidative stress in cardiovascular and renal remodeling and pathophysiology. This review details the results using GSBS patients that provide a deeper understanding of Ang II signaling and its associated oxidants/oxidative stress in humans. By providing a more complete and complex picture of cardiovascular and renal remodeling pathways and processes, studies of GSBS can inform the identification and selection of new targets and therapies to treat these and other oxidant-related disorders.

Desmosomes and their autoimmune pathologies

Desmosomes guarantee the integrity of the epidermis, by functioning both as an adhesive complex and as a cell-surface attachment site for the keratin intermediate filaments of the cytoskeleton. Considerable progress has been made in our knowledge of desmosomes and their components. The structure and function of many of the desmosomal molecules have been determined, and a number of the molecular interactions between desmosomal proteins have been elucidated. Desmosomal proteins are major antigens in pemphigus. Each type of pemphigus has its own antigenic targets, but in the last few years it has been shown that certain autoantibody populations are not restricted to just one form of pemphigus. The production of autoantibodies against multiple intracellular and extracellular desmosomal proteins, whose pathogenic role remains to be elucidated, suggests an overlapping distribution of antibody specificities among different forms of pemphigus.

Measuring the activity of the disease in patients with cutaneous lupus erythematosus

The Systemic Lupus Activity Measure (SLAM) is a system proposed by rheumatologists to measure disease activity in their patients with systemic lupus erythematosus (LE). It involves scoring a group of clinical symptoms and laboratory findings, the maximum possible score being 84. In systemic LE, the mid-point is between 9 and 12. We applied SLAM to 176 patients with cutaneous LE. Ninety-seven had localized discoid LE (L-DLE), 59 had disseminated discoid LE (D-DLE) and 20 had subacute cutaneous LE (SCLE). Eighty-five patients had low activity disease (0-4 points), 72 mildly active disease (5-9 points), 15 moderately active disease (10-14 points) and only four had very active disease (>/= 15 points). The most frequent lesions in patients who scored more than 10 points were photosensitivity, cicatricial alopecia, Raynaud's phenomenon and oral ulcers. Fifty patients were followed up for more than 5 years (mean follow-up 9 years). Nine of these had an increased SLAM score. Seven had L-DLE, one D-DLE and one SCLE. Seven of the 50 patients had photosensitivity, five cicatricial alopecia, five non-cicatricial alopecia, two Raynaud's phenomenon and two oral ulcers. Three patients who started with L-DLE evolved to D-DLE. The SLAM system is useful in the monitoring of disease activity in patients with cutaneous LE. Over time, even L-DLE patients may develop active disease. Photosensitivity, alopecia, oral ulcers and Raynaud's phenomenon seem to herald a worse prognosis.