Role of serum complement C3 and C4 on kidney outcomes in IgA nephropathy.

IgA Nephropathy (IgAN) is the most prevalent glomerular disease worldwide. Complement system activation is crucial in its pathogenesis. Few studies correlated serum C3 and C4 with disease activity and prognosis. This retrospective study investigated the prognostic value of serum complement at the time of diagnosis in patients with IgAN. Specifically we evaluated whether adding serum C3 and C4 levels to established predictive models-one based on variables related to chronic kidney disease (CKD) progression and another incorporating variables from the International IgA Prediction Tool (IntIgAPT)-enhances the accuracy of outcome prediction. A composite renal outcome was defined as 50% decline in eGFR or onset of kidney failure. 101 patients were stratified according to baseline C3 levels in three groups (Low, Medium and High). During a median follow-up of 54 months, the Low group exhibited higher incidence of primary outcome (16.3 events vs 2.9 and 1.7 events × 100 pts/year, p = 0.0026). Model-1 (M1), consisting of CKD progression variables, and Model-3 (M3), comprising IntIgANPT variables, were implemented with baseline C3 and C4 to create Model-2 (M2) and Model-4 (M4), respectively. M2 demonstrated better predictive performance over M1, showing higher discrimination (lower AIC and BIC, higher C-index and NR2). Similarly, M4 outperformed M3, showing enhanced outcome prediction when C3 and C4 levels were added. Implementation of serum C3 and C4 can enhance prediction accuracy of already-validated prognostic models in IgAN. Lower C3 and higher C4 levels were associated with poorer prognosis, highlighting a more 'Complement-Pathic' subset of patients.

Improving Kidney Disease Care: One Giant Leap for Nephrology.

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.

Fabry Disease Nephropathy: Histological Changes With Nonclassical Mutations and Genetic Variants of Unknown Significance.

RATIONALE & OBJECTIVE: Fabry disease (FD) is an X-linked genetic disorder that causes lysosomal storage of glycosphingolipids, primarily globotriaosylceramide (Gb3) and its derivative globotriaosylsphingosine (lyso-Gb3), with multiorgan dysfunction including chronic kidney disease. Affected individuals may be carriers of gene variants that are of uncertain significance (GVUS). We describe kidney pathology at the early stages of FD-related kidney disease to gain insights into its association with GVUS and sex. STUDY DESIGN: Single-center, case series. SETTING & PARTICIPANTS: Thirty-five consecutively biopsied patients (aged 48.1±15.4 years, 22 females) from among 64 patients with genetically diagnosed FD. Biopsies were retrospectively screened using the International Study Group of Fabry Nephropathy Scoring System. OBSERVATIONS: Genetic mutation type, p.N215S and D313Y, sex, age, estimated glomerular filtration rate (eGFR), plasma lyso-Gb3 (pLyso-Gb3) levels, and histological parameters, including Gb3 deposits were recorded. Genetic analyses showed mostly missense mutations, p.N215S variant in 15, and the "benign polymorphism" D313Y in 4 of the biopsied patients. Morphological lesions were similar for men and women except for interstitial fibrosis and arteriolar hyalinosis being more common in men. Early in their clinical course, patients with normal/mild albuminuria had podocyte, tubular, and peritubular capillary vacuoles/inclusions, and evidence of chronicity, i.e., glomerulosclerosis, interstitial fibrosis, tubular atrophy. These findings appeared to be associated with pLyso-Gb3, eGFR, and age. LIMITATIONS: Retrospective design and inclusion of outpatients partially based on family pedigree. CONCLUSIONS: In early stages of kidney disease in the setting of FD, numerous histological abnormalities are present. These observations suggest that kidney biopsies early in FD may reveal activity of kidney involvement that may inform clinical management.

Anti-Inflammatory Approach in Chronic Dialysis Patients with SARS-CoV-2: ATA or PMMA Dialyzers?

INTRODUCTION: High-flux hemodialysis membranes may modulate the cytokine storm of SARS-CoV-2, but their impact on chronic hemodialysis (CHD) patients is unknown. The aim of the study was the evaluation of asymmetric cellulose triacetate (ATA) and polymethylmethacrylate (PMMA) dialyzers on inflammatory markers and clinical outcomes in CHD patients with SARS-CoV-2. METHODS: A prospective, observational study on CHD patients with SARS-CoV-2 was carried out. Patients were enrolled from March 2020 to May 2021. Pre- and postdialysis C-reactive protein (CRP), procalcitonin (PCT), and interleukin-6 (IL-6) were determined at each session. Patients who underwent on-line hemodiafiltration (OLHDF) with a PMMA dialyzer were compared with those treated with OLHDF with a ATA dialyzer. The primary endpoint was the differences in the reduction ratio per session (RR) of CRP, PCT, IL-6, and IL-6 RR >25%. RESULTS: We consecutively enrolled 74 CHD patients with COVID-19, 48 were treated with ATA membrane, and 26 with PMMA. Median IL-6 RR was higher in the ATA group compared to PMMA (17.08%, IQR -9.0 to 40.0 vs. 2.95%, IQR -34.63 to 27.32). Median CRP RR was 7.77% (IQR 2.47-13.77) in the ATA group versus 4.8% (IQR -2.65 to 11.38) in the PMMA group (p = 0.0017). Median PCT-RR% was 77.38% (IQR 70.92-82.97) in ATA group versus 54.59% (IQR 42.62-63.16) in the PMMA group (p < 0.0001). A multiple logistic regression analysis with IL-6 RR >25% as the outcome including the membrane employed, pre-dialysis IL-6, CRP, PCT, and ferritin showed that ATA led to a higher probability to reach the outcome (OR 1.891, 95% CI 1.273-2.840, p = 0.0018) while higher CRP favors the risk of lower IL-6 RR values (OR 0.910, 95% CI 0.868-0.949, p ≤ 0.0001). CONCLUSIONS: In SARS-CoV-2 CHD patients treated with OLHDF, ATA showed a better anti-inflammatory profile, regarding IL-6 RR, compared to PMMA.