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Background: Renal injury related to Waldenström macroglobulinemia (WM) occurs in approximately 3% of patients. Kidney biopsy is crucial to discriminate between distinct histopathological entities such as glomerular (amyloidotic and non-amyloidotic), tubulo-interstitial and non-paraprotein mediated renal damage. In this context, disease characterization, management, relationship between renal, and hematological response have been poorly explored. We collected clinical, genetic and laboratory data of seven cases of biopsy-proven renal involvement by WM managed at our academic center and focused on three cases we judged paradigmatic discussing their histopathological patterns, clinical features, and therapeutic options., Case: In this illustrative case series, we confirm that serum creatinine levels and 24 h proteinuria are parameters that when altered should prompt the clinical suspicion of WM-related renal involvement, even if at present there are not precise cut-off levels recommending the execution of a renal biopsy. In our series AL Amyloidosis (n = 3/7) and tubulo-interstitial infiltration by lymphoma cells (n = 3/7) were the two more represented entities. BTKi did not seem to improve renal function (Case 1), while bortezomib-based regimens demonstrated a beneficial activity on the hematological and organ response, even when used as second-line therapy after chemoimmunotherapy (Case 3) and also with coexistence of anti-MAG neuropathy (Case 2). In case of poor response to bortezomib, standard chemoimmunotherapy (CIT), such as rituximab-bendamustine, represents an effective option (Case 1, 6, and 7). In our series, CIT generates durable responses more frequently in cases with amyloidogenic renal damage (Case 1, 5, and 7)., Conclusion: In this illustrative case series, we confirm that serum creatinine levels and 24 h proteinuria are parameters that when altered should prompt the clinical suspicion of WM-related renal involvement, even if at present there are not precise cut-off levels recommending the execution of a renal biopsy. Studies with higher numerosity are needed to better clarify the pathological and clinical features of renal involvement during WM and to determine the potential benefit of different therapeutic regimens according to the histopathological subtypes., (© 2024 The Authors. Cancer Reports published by Wiley Periodicals LLC.)

Background: Parietal epithelial cells are a heterogeneous population of cells located on Bowman's capsule. These cells are known to internalize albumin with a still undetermined mechanism, although albumin has been shown to induce phenotypic changes in parietal epithelial cells. Proximal tubular cells are the main actors in albumin handling via the macromolecular complex composed by ClC-5, megalin, and cubilin. This study investigated the role of ClC-5, megalin, and cubilin in the parietal epithelial cells of kidney biopsies from proteinuric lupus nephritis patients and control subjects and identified phenotypical changes occurring in the pathological milieu., Methods: Immunohistochemistry and immunofluorescence analyses for ClC-5, megalin, cubilin, ANXA3, podocalyxin, CD24, CD44, HSA, and LTA marker were performed on 23 kidney biopsies from patients with Lupus Nephritis and 9 control biopsies (obtained from nephrectomies for renal cancer)., Results: Two sub-populations of hypertrophic parietal epithelial cells ANXA3 + /Podocalyxin - /CD44 - , both expressing ClC-5, megalin, and cubilin and located at the tubular pole, were identified and characterized: the first one, CD24 + /HSA - /LTA -  had characteristics of human adult parietal epithelial multipotent progenitors, the second one, CD24 - /LTA + /HSA + committed to become phenotypically proximal tubular cells. The number of glomeruli presenting hypertrophic parietal epithelial cells positive for ClC-5, megalin, and cubilin were significantly higher in lupus nephritis patients than in controls., Conclusions: Our results may provide further insight into the role of hypertrophic parietal epithelial cells located at the tubular pole and their possible involvement in protein endocytosis in lupus nephritis patients. These data also suggest that the presence of hypertrophic parietal epithelial cells in Bowman's capsule represents a potential resource for responding to protein overload observed in other glomerulonephritis., (© 2023. The Author(s).)

Despite type 2 diabetes mellitus (T2D) is commonly considered a detrimental factor in dialysis, its clear effect on morbidity and mortality on waitlisted patients for kidney transplant (KT) has never been completely elucidated. We performed a retrospective analysis on 714 patients admitted to wait-list (WL) for their first kidney transplant from 2005 to 2010. Clinical characteristics at registration in WL (age, body mass index -BMI-, duration and modality of dialysis, underlying nephropathy, coronary artery -CAD- and/or peripheral vascular disease), mortality rates, and effective time on WL were investigated and compared according to T2D status (presence/absence). Data about therapy and management of T2D were also considered. At the time of WL registration T2D patients (n = 86) were older than non-T2D (n = 628) (58.7 ± 8.6 years vs 51.3 ± 12.9) with higher BMI (26.2 ± 3.8 kg/m 2 vs 23.8 ± 3.6), more frequent history of CAD (33.3% vs 9.8%) and peripheral vascular disease (25.3% vs 5.8%) (p < 0.001 for all analyses). Considering overall population, T2D patients had reduced survival vs non-T2D (p < 0.001). Transplanted patients showed better survival in both T2D and non-T2D groups despite transplant rate are lower in T2D (75.6% vs 85.8%, p < 0.001). T2D was also associated to similar waiting time but longer periods between dialysis start and registration in WL (1.6 years vs 1.2, p = 0.008), comorbidity-related suspension from WL (571 days vs 257, p = 0.002), and increased mortality rate (33.7% vs 13.9% in the overall population, p < 0.001). In T2D patients admitted to WL, an history of vascular disease was significantly associated to low patient survival (p = 0.019). In conclusion, T2D significantly affects survival also on waitlisted patients. Allocation policies in T2D patients may be adjusted according to increased risk of mortality and WL suspension due to comorbidities.

Purpose: Gitelman's syndrome (GS) presents normo-hypotension and absence of cardiovascular-renal remodeling despite high angiotensin II (Ang II), activation of renin-angiotensin-aldosterone system and is a human model of endogenous antagonism of Ang II signaling, opposite to hypertension. GS's clinical presentation leads to questions regarding what features might be responsible. One area of investigation involves Ang II signaling. In hypertensive patients, RhoA/Rho kinase (RhoA/ROCK) pathway activation by Ang II is involved in hypertension development/maintenance and induction of long-term consequences (cardiovascular-renal remodeling), while GS has reduced p63RhoGEF gene and protein levels and ROCK activity. Ang II signaling is mediated by Gαq, which interacts with p63RhoGEF via the α6-αN linker connecting p63RhoGEF's DH and PH domains acting as a conformational switch to activate RhoA/ROCK signaling., Methods: We have investigated in GS patients, the presence of mutations in either p63RhoGEF's α6-αN linker domain and in Gαq's Ala253, Trp263, and Tyr356 residues, crucial for p63RhoGEF-Gαq interplay., Results: No mutations have been found in specific aminoacids of p63RhoGEF α6-αN linker and Gαq, key for p63RhoGEF/Gαq interplay., Conclusions: Gitelman's syndrome normo/hypotension and lack of cardiovascular-renal remodeling are not due to mutations of p63RhoGEF α6-αN linker and Gαq interactions. This opens the way for investigations on different coding and no-coding regions (p63RhoGEF and Gαq promoters) and on altered transcriptional/post-transcriptional regulation. Clarification of how these biochemical/molecular mechanisms work/interact would provide insights into mechanisms involved in the GS's Ang II signaling fine tuning, in human physiology/pathophysiology in general and could also identify significant targets for intervention in the treatments of hypertension.

Post-transplant hypertension is a common occurrence during treatment with calcineurin inhibitors (CNIs) in kidney transplant population. The pathogenesis of vasoconstriction induced by CNIs involves vascular tone alterations and kidney sodium transport regulation. Among the factors involved a key role is played by the activation of intrarenal renin-angiotensin system with enhanced release of Angiotensin II (Ang II) and increase of oxidative stress. A common pathway between oxidative stress and hypertension induced by CNIs may be identified in the involvement of the activation of RhoA/Rho kinase pathway, key for the induction of hypertension and cardiovascular-renal remodeling, of the oxidative stress mediated increased nitric oxide (NO) metabolism and increased renal sodium retention via increased activity of thiazide-sensitive sodium chloride cotransporter (NCC) in the distal tubule. We examined literature data including those coming from our group regarding the role of oxidative stress and sodium retention in CNIs induced hypertension and their involvement in cardiovascular-renal remodeling. Based on the available data, we have provided support to the activation of RhoA/Rho kinase pathway as an important effector in the pathophysiology of CNIs induced post-transplant hypertension via activation of oxidative stress and sodium retention. Clarification of how the biochemical and molecular mechanisms that regulate the processes involved in CNIs induced post transplant hypertension work and interact, would provide further insights not only into the comprehension of the pathophysiology of CNIs induced post transplant hypertension but could also have a positive impact on the clinical ground through the identification of significant targets. Their specific pharmacologic targeting might have multiple beneficial effects on the whole cardiovascular-renal function. The demonstration that in kidney transplanted patients with CNIs induced post-transplanted hypertension, the treatment of hypertension with different antihypertensive drugs inducing a comparable blood pressure reduction but different effects for example on oxidative stress and oxidative stress related proteins and/or Rho kinase and sodium retention, could be helpful for the choice of the antihypertensive treatment in these patients which takes advantage from effects of these drugs beyond blood pressure reduction., (© 2017 The Author(s). Published by S. Karger AG, Basel.)

Aims: Cardiovascular disease (CVD) is the leading cause of excess mortality in chronic kidney disease (CKD) and dialysis patients (DP) who have higher prevalence of left ventricular hypertrophy (LVH), the strongest predictor of CV events. Rho kinase (ROCK) activation is linked in hypertensive patients to cardiac remodeling while ROCK inhibition suppresses cardiomyocyte hypertrophy and, in a human clinical condition opposite to hypertension, its downregulation associates with lack of CV remodeling. Information on ROCK activation-LVH link in CKD and DP is lacking., Materials and Methods: Mononuclear cells (PBMCs) MYPT-1 phosphorylation, a marker of ROCK activity, and the effect of fasudil, a ROCK inhibitor, on MYPT-1 phosphorylation were assessed in 23 DPs, 13 stage 3-4 CKD and 36 healthy subjects (HS) by Western blot. LV mass was assessed by M-mode echocardiography., Key Findings: DP and CKD had higher MYPT-1 phosphorylation compared to HS (p<0.001 and p=0.003). Fasudil (500 and 1000μM) dose dependently reduced MYPT-1 phosphorylation in DP (p<0.01). DP had higher LV mass than CKD (p<0.001). MYPT-1 phosphorylation was higher in patients with LVH (p=0.009) and correlated with LV mass both in DP and CKD with LVH (p<0.001 and p=0.006)., Significance: In DP and CKD, ROCK activity tracks with LVH. This ROCK activation-LVH link provided in these CVD high-risk patients along with similar findings in hypertensive patients and added to opposite findings in a human model opposite to hypertension and in type 2 diabetic patients, identify ROCK activation as a potential LVH marker and provide further rationale for ROCK activation inhibition as target of therapy in CVD high-risk patients., (Copyright © 2016 Elsevier Inc. All rights reserved.)

Hypothesis/introduction: Angiotensin II (Ang II) has been shown to control erythropoietin (EPO) synthesis as Ang II type 1 receptor (AT1R) blockers block Ang-II-induced EPO oversecretion. To further explore the involvement of AT1R in processes controlling EPO levels, plasma EPO and mononuclear cell NADPH oxidase 4 (NOX4) - a NOX family member involved in oxygen sensing, which is a process central to controlling EPO levels - were assessed in Bartter's/Gitelman's syndrome (BS/GS) patients, a human model of endogenous AT1R antagonism and healthy subjects. Heme oxygenase (HO)-1, antioxidant and anti-inflammatory factor related to NOX4 activation, and the relationship of EPO and NOX4 to HO-1 were also assessed., Materials and Methods: EPO was measured by chemiluminescent immunoassay, HO-1 by sandwich immunoassay and NOX4 protein expression by Western blot., Results: EPO was increased in BS/GS patients compared to healthy subjects (7.64 ± 2.47 vs. 5.23 ± 1.07 U/l; p = 0.025), whereas NOX4 did not differ between BS/GS and healthy subjects (1.76 ± 0.61 vs. 1.65 ± 0.54 densitometric units; p = n.s.), and HO-1 was increased in BS/GS patients compared to healthy subjects (9.58 ± 3.07 vs. 5.49 ± 1.04 ng/ml; p = 0.003). NOX4 positively correlated with HO-1 only in BS/GS patients; no correlation was found between EPO and either NOX4 or HO-1 in those two groups., Conclusions: The effect of the renin-angiotensin system on EPO cannot be solely mediated by Ang II via AT1R signaling, but rather, EPO levels are also determined by a complex interrelated set of signals that involve AT2R, nitric oxide levels, NOX4 and HO-1 activity.

Multiple observational studies along with a limited number of randomized clinical trials suggest that intensive hemodialysis (IHD) not only improves outcomes for uremic patients undergoing chronic dialysis but does so with a more favorable cost/benefit ratio compared with conventional hemodialysis. As a result of this, there has been a rapid increase in the interest in home hemodialysis (HHD) as HHD represents the easiest means of implementing IHD. While HHD has generated increased interest given its association with better outcomes/reduced hospitalizations, there are very few randomized controlled trials comparing HHD with other hemodialysis methods. Reported HHD-associated increased survival benefits compared with in-center hemodialysis are from uncontrolled studies, which raise patient selection bias as underlying the differences found. Thus, while HHD draws increasing attention, studies that pay careful attention to the psychosocial, demographic, and clinical factors associated with patients selected to undergo HHD will be needed to ultimately demonstrate its benefits, clarify the clinical applications, and determine the limits of IHD use in dialysis patients., (Copyright © 2015 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.)

The purpose of this study was to analyze the relationship between intravenous (i.v) drug use practices and the prevalence of human immunodeficiency virus (HIV), hepatitis B virus (HBV) and hepatitis C virus (HCV) in 146 heterosexual male i.v. drug users (IVDUs) attending a methadone-maintainance treatment program in Catanzaro, Southern Italy. One hundred and forty-six heterosexual male IVDUs attending a methadone-maintainance treatment program in Catanzaro were interviewed in order to obtain the following information: age, number of drug injections (calculated by multiplying the mean number of daily injections by 365 and then by the number of years of injections), number of injection equipment-sharing partners in the last year, number of sexual partners in the last year and possible IV cocaine use. Their sera were studied for the presence of antibodies to HIV, HBV and HCV by commercial enzyme-linked-immuno-sorbent assays run in duplicate. HIV positive samples were confirmed by Western Blot assay. Sixteen per cent of IVDUs were anti-HIV positive, 40% were anti-HBc positive and 68% were anti-HCV positive. Twenty-three per cent were seronegative and 12% were seropositive for all 3 viral markers. Multiple logistic analysis of HIV, HBV and HCV seropositivities in relation to age, number of drug injections, i.v. cocaine use and presence of injection equipment-sharing partners in the last year, showed that: a) older age (more than 27 years) was significantly associated with all 3 viral infections (mainly with HIV); b) i.v. cocaine use was associated with HBV, but even more with HIV; c) injection equipment-sharing partners in the last year was directly associated with HCV and inversely with HIV. No significant association was observed with the number of drug injections and the number of sexual partners. In conclusion, this study: a) demonstrates a difference of prevalence for HIV, HBV and HCV serum markers in this group of IVDUs from Catanzaro, Southern Italy; b) underlines the importance of i.v. cocaine use in the spreading of HIV; c) emphasizes the need of preventive strategies.

A higher seroprevalence of anti-HCV antibodies (63.4%) was found in 41 intravenous drug addicts (IVDA) when compared to 220 controls (1.8%). Life style is an important risk factor for HCV transmission among IVDA.