Bioelectrical impedance vector analysis and brain natriuretic peptide in the evaluation of patients with chronic kidney disease in hemodialitic treatment.

INTRODUCTION: Setting dry weight (DW) in haemodialysis (HD) patients is still an hard issue. Several clinical, haematochimical and instrumental parameters have been considered. In the last years bioelectrical impedance vector analysis (BIVA) became the main method to evaluate body composition and water body percentage. However it is still difficult to assess the nutritional status and identify a correct DW in HD patients. AIM: to set DW and nutritional status, combining BIVA with phase angle (PhA) and serum brain natriuretic peptide (BNP) in HD patients. METHODS: we evaluated PhA and BNP modifications before (T0), after HD section (T1) and after 60 days (T2), in all patients treated in our HD centre. RESULTS: A total of 50 patients (36 males) with a mean age of 70.1 ± 8.85 years, were recruited. We did not report significant changes in BNP and PhA between T0 and T1, while they were significantly different between T0 and T2. We also reported a significant difference between T0 and T2 in ECW / TBW, while we did not show significant variations in ECM / BMC between T0, T1 and T2 indicating a stability of the nutritional status. PhA, BNP and ECW / TBW, returned to a normal value in patients in which we reached a DW, also considering clinical parameters such as blood pressure and antihypertensive therapy. The weight loss obtained with the evaluation of the BIVA and the BNP was 1.2-5.7 kg, greater than that calculated empirically which stood at around 0.9-4.3 Kg. CONCLUSION: We suggest to carry out BIVA with PhA combined with BNP to assess an adequate DW and evaluate a correct nutritional status in HD patients.

Ischemic Nephropaty: The Role of the Renal Artery Stenosis Revascularization on Renal Stem Cells.

We report the case of a 65-year-old man with acute GFR decline to 37 mL/min and uncontrolled high blood pressure. He was suspected for renovascular hypertension and underwent a renal color Doppler ultrasound scan that detected a bilateral atherosclerotic renal artery stenosis. A digital selective angiography by percutaneous transluminal angioplasty and stenting (PTRAs) was successfully performed. Blood pressure rapidly normalized, GFR increased within a few days, and proteinuria disappeared thereafter. These clinical goals were accompanied by a significant increase of circulating renal stem cells (RSC) and a slight increase of resistive index (RI) in both kidneys. This single observation suggests the need for extensive studies aimed at evaluating the predictive power of RI and RSC in detecting post-ischemic renal repair mechanisms.

Residents' satisfaction and suggestions to improve nephrology residency in Italy, and comparison with the organization in other European countries.

BACKGROUND: In Italy, nephrology residency is available in twenty-one nephrology schools, each with its own strengths and weaknesses. The present study is aimed at exploring the residents' satisfaction with their training programs. METHODS: Between April 20th and May 19th, 2021, a questionnaire on residency satisfaction consisting of 49 items was sent to 586 residents and 175 recently certified specialists (qualified to practice as nephrologists in 2019 and 2020), with a response rate of 81% and 51%, respectively. The teaching organization was contextualized with a survey involving 13 European nephrology schools. RESULTS: Most residency fellowship programs received a good rating with regard to "satisfaction", in particular for the following items: number of hospitalizations followed-up, chronic hemodialysis training, follow-up of transplanted patients, diagnosis and treatment of glomerulonephritis. The teachings that were identified as being of lower quality or insufficient intensity included vascular access management, ultrasound diagnostics and renal nutrition. The need for improvement in formal teaching programs was underlined. Young nephrologists were rather satisfied with their salary and with the quality of the work they were doing, but only few were interested in an academic career since it was generally held that it is "too difficult" to obtain a university position. Many young nephrologists who filled in the questionnaire felt that lack of experience in peritoneal dialysis and vascular access management was a barrier to finding an ideal job. Compared to other European training programs, the Italian program differs with regard to longer exposure to nephrology (as compared to internal medicine), and greater flexibility for internships in different settings, including abroad. CONCLUSIONS: This first nationwide survey on the satisfaction of residents in nephrology indicates that, despite rather good overall satisfaction, there is room for improvement to make nephrology a more appealing choice and to fulfill the needs of a growing number of renal disease patients.

COVID-19 Infection in Autosomal Dominant Polycystic Kidney Disease and Chronic Kidney Disease Patients: Progression of Kidney Disease.

INTRODUCTION: the COVID-19 pandemic has brought to light the intricate interplay between viral infections and preexisting health conditions. In the field of kidney diseases, patients with Autosomal Dominant Polycystic Kidney Disease (ADPKD) and Chronic Kidney Disease (CKD) face unique challenges when exposed to the SARS-CoV-2 virus. This study aims to evaluate whether SARS-CoV-2 virus infection impacts renal function differently in patients suffering from ADPKD and CKD when compared to patients suffering only from CKD. MATERIALS AND METHODS: clinical data from 103 patients were collected and retrospectively analyzed. We compared the renal function of ADPKD and CKD patients at two distinct time points: before COVID-19 infection (T0) and 1 year after the infection (T1). We studied also a subpopulation of 37 patients with an estimated glomerular filtration rate (eGFR) < 60 mL/min and affected by ADPKD and CKD. RESULTS: clinical data were obtained from 59 (57.3%) ADPKD patients and 44 (42.7%) CKD patients. At T1, ADPKD patients had significantly higher serum creatinine levels compared to CKD patients, and a significantly lower eGFR was observed only in ADPKD patients with eGFR < 60 mL/min compared to CKD patients (p < 0.01, p < 0.05; respectively). Following COVID-19 infection, ADPKD-CKD patients exhibited significantly higher variation in both median serum creatinine (p < 0.001) and median eGFR (p < 0.001) compared to CKD patients. CONCLUSION: the interplay between COVID-19 and kidney disease is complex. In CKD patients, the relationship between COVID-19 and kidney disease progression is more established, while limited studies exist on the specific impact of COVID-19 on ADPKD patients. Current evidence does not suggest that ADPKD patients are at a higher risk of SARS-CoV-2 infection; however, in our study we showed a significant worsening of the renal function among ADPKD patients, particularly those with an eGFR < 60 mL/min, in comparison to patients with only CKD after a one-year follow-up from COVID-19 infection.

MicroRNA and renal fibrosis in autosomal dominant polycystic kidney disease: a longitudinal study.

BACKGROUND: Autosomal dominant polycystic kidney disease (ADPKD) is a hereditary kidney disorder that may progress to kidney failure, accounting for 5-10% of all patients with end-stage kidney disease (ESKD). Clinical data, as well as molecular genetics and advanced imaging techniques have provided surrogate prognostic biomarkers to predict rapid decline in kidney function, nonetheless enhanced tools for assessing prognosis for ADPKD are still needed. The aim of this study was to analyze specific microRNAs involved in the pathogenesis of ADPKD and in the development of renal fibrosis, evaluating their potential role as predictors of renal function loss. METHODS: We evaluated kidney function by estimated glomerular filtration rate (eGFR) in 32 ADPKD patients in different stages of kidney disease at T0 and after a 24-month follow up (T1). Patients were divided into two groups: Rapid disease progression ([RP], n 15) and Non-rapid disease progression ([NRP], n 17), according to the Mayo Clinic classification criteria. At T0, ADPKD patients underwent plasma sampling for quantitative analysis of h-miR-17-5p, h-miR-21-5p and h-miR-199a-5p microRNA expression, using the quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) method and a 3 T magnetic resonance imaging (MRI), using an advanced MRI imaging protocol, for the quantification of total kidney volume (TKV), total perfusion volume (TPV) and total fibrotic volume (TFV). RESULTS: The expression of h-miR17-5p was higher (p < 0.05) in ADPKD patients with rapid disease progression. h-miR-17-5p, h-miR-21-5p and h-mir-199-5p showed a positive and significant correlation with the eGFR slope (mL/min/1.73 m2/year) (p < 0.05) but not with the eGFR at both T0 and T1. Both total fibrotic volume (cm3) and height-adjusted total fibrotic volume (cm3/m) were positively and significantly correlated to h-miR 21-5p and h-miR 199-5p (p < 0.05), but not to total kidney volume (cm3) and height-adjusted total kidney volume (cm3/m). CONCLUSIONS: The microRNAs we studied were associated with fibrosis and renal damage, suggesting their possible role as biomarkers able to identify ADPKD patients at high risk of disease progression regardless of the degree of kidney function, and therefore suitable for medical therapy, and may help uncovering new molecular mechanisms underlying cystogenesis.

Parasympathetic activity and total fibrotic kidney in autosomal-dominant polycystic kidney disease patients: a pilot study.

PURPOSE: Renin-angiotensin system hyperactivation in autosomal-dominant polycystic kidney disease (ADPKD) patients leads to early hypertension. Cystic enlargement probably causes parenchymal hypoxia, renin secretion, and endothelial dysfunction. Sympathetic and parasympathetic balance is altered in this condition, especially during the night, also affecting blood pressure circadian rhythm. Aim of this study was to evaluate sympathetic/parasympathetic balance using heart rate variability (HRV) parameters and find a correlation between HRV and renal damage progression, as total kidney volume enlargement, in ADPKD patients. METHODS: Sixteen adult ADPKD patients were enrolled in the study. Eleven patients (68.8%) were male, and the median age was 42 years (IQR 36-47.5). HRV parameters were calculated using 24 h-ECG Holter. A kidney magnetic resonance imaging (MRI) scan 3 Tesla was performed to evaluate total kidney volume (TKV) and total fibrotic volume (TFV). RESULTS: A statistically significant positive linear correlation was observed between length of kidneys and frequency domain parameters as low frequency (LF) (r = 0.595, p < 0.05) and LFday (r = 0.587, p < 0.05). Moreover, a statistically significant positive linear correlation exists between high frequency (HF) and TFV (r = 0.804, p < 0.01) or height-adjusted (ha) TFV (r = 0.801, p < 0.01). Finally, we found a statistically significant positive linear correlation between HFnight and TKV (r = 0.608, p < 0.05), ha-TKV (r = 0.685, p < 0.01), TFV (r = 0.594, p < 0.05), and ha-TFV (r = 0.615, p < 0.05). CONCLUSION: We suppose that the increase in TKV and TFV could lead to a parasympathetic tone hyperactivation, probably in response to hypoxic stress and vasoconstriction due to cystic enlargement.

Contrast-Induced Acute Kidney Injury and Endothelial Dysfunction: The Role of Vascular and Biochemical Parameters.

INTRODUCTION: Contrast-induced acute kidney injury (CIAKI) is one of the main causes of acute renal failure in hospitalized patients, following the administration of iodinated contrast medium used for CT scans and angiographic procedures. CIAKI determines a high cardiovascular risk and appears to be one of the most feared complications of coronary angiography, causing a notable worsening of the prognosis with high morbidity and mortality. AIM: To evaluate a possible association between the renal resistive index (RRI) and the development of CIAKI, as well as an association with the main subclinical markers of atherosclerosis and the main cardiovascular risk factors. MATERIALS AND METHODS: We enrolled 101 patients with an indication for coronary angiography. Patients underwent an assessment of renal function (serum nitrogen and basal creatinine, 48 and 72 h after administration of contrast medium), inflammation (C reactive protein (CRP), serum calcium and phosphorus, intact parathormone (iPTH), 25-hydroxyvitaminD (25-OH-VitD), serum uric acid (SUA), total cholesterol, serum triglycerides, serum glucose and insulin). All patients also carried out an evaluation of RRI, intima-media thickness (IMT), interventricular septum (IVS) and the ankle-brachial index (ABI). RESULTS: 101 patients (68 male), with a mean age of 73.0 ± 15.0 years, were enrolled for the study; 35 are affected by type 2 diabetes mellitus. A total of 19 cases of CIAKI were reported (19%), while among diabetic patients we reported an incidence of 23% (8 patients). In our study, patients with CIAKI had significantly higher RRI (p < 0.001) and IMT (p < 0.001) with respect to the patients who did not develop CIAKI. Furthermore, patients with CIAKI had significantly higher CRP (p < 0.001) and SUA (p < 0.006). CONCLUSIONS: We showed a significant difference in RRI, IMT, SUA and CRP values between the population developing CIAKI and patients without CIAKI. This data appears relevant considering that RRI and IMT are low-cost, non-invasive and easily reproducible markers of endothelial dysfunction and atherosclerosis.

Sonographic evaluation of hypertension: Role of atrophic index and renal resistive index.

Hypertension can cause structural and functional renal damage. Intrarenal ultrasound parameters have been extensively investigated in hypertensive patients and among the parameters introduced, the renal resistive index (RI) is associated with the progression of chronic kidney disease and hypertension. Atrophic index (AI) is an indirect anatomical ultrasound index that reports the atrophic changes of the renal parenchyma and it is mainly studied in chronic glomerular diseases. The present study aimed to evaluate renal RI and AI in hypertensive patients with normal renal function. AI showed correlations with all parameters associated with renal function reduction (age, creatinine, and intrarenal arterial stiffness). AI, in combination with RI, can represent in hypertensive patients an additional marker for renal damage progression.