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Background: A considerable minority of patients on waiting lists for kidney transplantation either have no diagnosis (and fall into the subset of undiagnosed cases) because kidney biopsy was not performed or histological findings were non-specific, or do not fall into any well-defined clinical category. Some of these patients might be affected by a previously unrecognised monogenic disease., Methods: Through a multidisciplinary cooperative effort, we built an analytical pipeline to identify patients with chronic kidney disease (CKD) with a clinical suspicion of a monogenic condition or without a well-defined diagnosis. Following the stringent phenotypical and clinical characterization required by the flowchart, candidates meeting these criteria were further investigated by clinical exome sequencing followed by in silico analysis of 225 kidney-disease-related genes., Results: By using an ad hoc web-based platform, we enrolled 160 patients from 13 different Nephrology and Genetics Units located across the Piedmont region over 15 months. A preliminary "remote" evaluation based on well-defined inclusion criteria allowed us to define eligibility for NGS analysis. Among the 138 recruited patients, 52 (37.7%) were children and 86 (62.3%) were adults. Up to 48% of them had a positive family history for kidney disease. Overall, applying this workflow led to the identification of genetic variants potentially explaining the phenotype in 78 (56.5%) cases., Conclusions: These results underline the importance of clinical exome sequencing as a versatile and highly useful, non-invasive tool for genetic diagnosis of kidney diseases. Identifying patients who can benefit from targeted therapies, and improving the management of organ transplantation are further expected applications., (© 2020. The Author(s).)

Background: Patients (pts) with primary Membranous nephropathy (MN) have an autoimmune disease caused by autoantibodies against podocyte antigens and 60-80% of them have antibodies directed against the M-type phospholipase A2 receptor (PLA2R). Immunosuppressive treatment is recommended in high-medium risk pts. Recently the use of rituximab (RTX), has emerged as an important therapeutic option in pts with primary MN. The appropriate cumulative dose of RTX in PMN pts is still uncertain, and favorable outcomes even with low-dose of RTX has been described. We compared efficacy and safety of 3 different treatment regimens: low-dose RTX (Protocol 1, one dose of RTX 375 mg/m 2 ), standard RTX protocol (Protocol 2, four weekly doses of rituximab 375 mg/m 2 ) and Ponticelli's regimen., Methods: 42 pts with primary MN and nephrotic syndrome were assigned to Protocol 1 (14 pts) or Protocol 2 (14 pts). All patients were followed for 24 months after RTX. Fourteen pts, matched for age and baseline serum creatinine (sCr) and proteinuria, treated with Ponticelli's regimen were examined as controls., Results: At 24 months, a significant improvement in proteinuria levels was observed in pts treated with Protocol 1 (7.5 ± 4.8 at T0; 0.21 ± 0.15 at T24, p < 0.01), Protocol 2 (5.1 ± 1.41 g/24 at T0; 0.35 ± 0.39 at T24 p < 0.01) and controls (8.27 ± 4.78 T0; 2.2 ± 1.9 g/24 h at T24, p < 0.01). No differences in clinical response (p = 0.53) was observed comparing the 3 groups., Conclusions: Our data suggest that the RTX is a promising alternative to Ponticelli's regimen even at low-doses. This makes RTX a cost-effective treatment of primary MN in the short and medium terms.

Introduction: AL amyloidosis is caused by a clone of plasma cell. Due to the impact of the disease on patient survival, careful evaluation of organ involvement is essential and treatment should be tailored to single patient's risk., Aim: We analyzed the clinical, laboratory and histological characteristics of 21 elderly patients (pts) (mean age 74.7 ± 7.97 years, range 55-81) with AL amyloidosis, including 17 patients (81%) with biopsy-proven renal involvement, who were ineligible for bone marrow transplantation, and evaluated the impact of renal impairment on survival., Results: Cardiac and renal involvement was found in 14 (67%) cases. Among the 17 patients with renal involvement, 12 had renal failure with proteinuria, and one showed isolated renal failure and vascular amyloid deposition. Hematological response occurred in 57.1% after first line therapy (75% after three cycles). In six of the patients with renal involvement, proteinuria decreased from 4.2 to 1.1 g/24 h (range 0.2-3 g/24 h), serum Creatinina (sCr) levels declined or stabilized. Severe renal failure at diagnosis was found to directly influence patient survival, while the Staging System for Renal Outcome in AL Amyloidosis did not associate with outcomes., Conclusions: To the best of our knowledge this is the first case series in which the whole cohort of patients with urinary or functional abnormalities underwent a histological evaluation. None of the patients were eligible for bone marrow transplantation. Hematologic response was 57.1%, while renal response was much lower (35%). Of note, the Staging System did not completely apply to this peculiar setting of patients in whom renal involvement was not presumptive but biopsy-proven. More aggressive approaches may be needed in these patients to avoid the inexorable progression of the disease.

Background: In this study we aimed to evaluate the usefulness of domain profiling of Beta-2-glycoprotein I(β2GPI)-Domain-1 (D1) antibodies in relation to antiphospholipid antibodies (aPL)-related nephropathy (aPL-N) in patients with biopsy-proven lupus nephritis (LN)., Methods: Of 124 consecutive patients (96 women, mean age 45.5 ± 12.3 years, mean disease duration 14.7 ± 9.6 years) fulfilling the 1982 criteria for systemic lupus erythematosus (SLE), we identified 39 patients (mean age 39.84 ± 8.6 years, mean disease duration 11.3 ± 7.7 years) with the following characteristics: (a) biopsy-proven LN; (b) no previous diagnosis of antiphospholipid syndrome (APS) according to the current classification criteria., Results: Patients with both LN and aPL-N had higher median aβ2GPI-D1 antibody titres (220.1 CU, 25-75th IQ 29.1-334.2) as compared those with LN alone (46.5 CU, 25-75th IQ 12.5-75.1) (p = 0.0087). Median aβ2GPI-D1 antibody titres were higher in patients with acute thrombotic microangiopathy (aTMA) (N = 7) (250.1 CU, 25-75th IQ 61.2-334.2) vs. with LN alone (46.5 CU, 25-75th IQ 12.5-75.1 CU) (p = 0.0009). Having a Global Antiphospholipid Syndrome Score > 10 confers an increased probability of having acute features of aTMA (OR 6.25, 95%CI 1.2-31.8). As compared to other aPL, aβ2GPI-D1 antibodies have the best diagnostic accuracy for aTMA as evaluated by performances in Area Under the Curves in a ROC analysis., Conclusions: aβ2GPI-D1 antibodies detection might provide a second-line assay to be performed in aβ2GPI positive patients with LN, allowing more accurate stratification of the renal vascular involvement risk, thus potentially leading to a more tailored management.

Anticoagulation in patients with impaired kidney function can be challenging since drugs' pharmacokinetics and bioavailability are altered in this setting. Patients with chronic kidney disease (CKD) treated with conventional anticoagulant agents [vitamin K antagonist (VKA), low-molecular weight heparin (LMWH) or unfractionated heparin (UFH)] are at high risk of bleeding events (both non-major and major clinically relevant bleeding). While anticoagulation reduces the risk of thromboembolic events, the co-existing bleeding risk and the fact that the most commonly used anticoagulation agents are eliminated via the kidneys pose additional challenges. More recently, two classes of direct oral anticoagulant agents (DOACs) have been investigated for the prevention and management of venous thromboembolic events: the direct factor Xa inhibitors rivaroxaban, apixaban and edoxaban, and the direct thrombin inhibitor dabigatran. In this review, we discuss the complex challenges and the practical considerations associated with the management of anticoagulation treatment in patients with CKD, with a special focus on DOACs.

Background and Aims: Glucocorticoids have never been studied in a placebo-controlled manner in giant cell arteritis (GCA), but their effectiveness is well established. However, evidence for the efficacy of immunosuppressant drugs as steroid-sparing agents in this disease is highly desirable, especially in elderly patients. We report the use of mycophenolate mofetil (MMF) as a steroid-sparing agent in three patients (mean age 78 years) with GCA, at high risk of longterm high dose glucocorticoids because of type II diabetes mellitus, obesity, hypertension or osteoporosis., Methods: clinical monitoring and assessment of laboratory parameters were carried out weekly (first month) and then patients were seen in the clinic every 2 weeks. Vascular lesions were also monitored at the onset and during the follow-up by Doppler ultrasonography (every 3 months)., Results: all three patients showed clinical benefit, and were also able to taper steroid use to a more rapid regimen compared with the recently suggested steroid reduction approach. MMF was well tolerated, and no signs of toxicity were observed in a mean of 21.6 months (12-29) of follow-up., Conclusion: mycophenolate mofetil may be considered a steroid-sparing agent in elderly patients with GCA but, before results of controlled trials become available, MMF may be considered only for patients who do not improve or stabilize with conventional therapy, or in patients for whom reduced steroid dosage is highly recommended.

Background: IgA nephropathy (IgAN) is a microcosm of glomerular lesions. Some histologic lesions are irreversible and progress toward obliteration of glomerular capillaries. Others are acute inflammatory processes potentially susceptible to reversal by means of immunosuppressive therapies., Methods: The effects of a combined schedule of steroids and mycophenolate mofetil (MMF) was prospectively examined in a subset of IgAN patients with acute inflammatory histologic changes associated with proteinuria (mean 2,400 mg/day, range 1,130-5,250), hematuria (76 red cells per high-power microscopic field, range 30-100) and renal failure (serum creatinine 1.6 mg/dL, range 1.2-2.9). Patients had diffuse mesangial proliferation with at least 10% florid crescents, mild to moderate degrees of glomerular sclerosis and interstitial changes, and both mesangial and capillary deposition of immunoreactants at immunofluorescence. Treatment consisted of 3 pulses of methylprednisolone (15 mg/kg) followed by oral prednisone (0.8 mg/kg body weight, tapered until discontinuation within 4 months) and MMF 2 g for 6 months., Results: Serum creatinine, proteinuria and microscopic hematuria significantly dropped at 6 months compared with baseline values (p=0.01) and remained lower at the end of follow-up 51 months (range 24-90) later (p<0.01, for proteinuria and hematuria; p=0.08, for serum creatinine)., Conclusion: Therapy with steroids and MMF may be considered in a subset of IgAN patients with florid glomerular changes, functional impairment and major urinary abnormalities, to prevent subsequent progression toward renal failure.

Background: Proteasomes are 'proteolytic machineries' implicated in many cellular functions, including protein turnover, inflammatory response and immunosurveillance. They exist in various forms sharing the same catalytic core - the 20S proteasome. This core consists of 28 subunits codified by 14 different genes, 3 of which - beta 1, beta 2 and beta 5 - are catalytically active and show peptidyl-glutamyl peptide hydrolyzing (PGPH), trypsin-like and chymo-trypsin-like activities, respectively. Under IFN- delta and TNF- alfa stimuli, the 3 active constitutive subunits are replaced by the corresponding ones - i.e., LMP2, MECL-1, LMP7 - known as inducible subunits, thus resulting in the constitution of the 'immunoproteasome' that is specifically implicated in MHC class I-presented peptide generation. This process is enhanced when the proteasome is associated with the polymeric protein 11S regulator/PA28 made up of 4 alfa and 3 beta subunits., Methods: The 20S proteasome was purified from post mortem specimens of human kidney cortex by chromatographic and ultracentrifugation techniques. It was then characterized on the basis of (i) multicatalytic activity evaluated using specific fluorogenic peptides, (ii) electrophoretic mobility on non-denaturating polyacrylamide gels followed by in-gel visualization by fluorogenic peptide overlaying and Coomassie blue staining and (iii) subunit composition as ascertained by SDS-PAGE and 2-dimensional electrophoresis followed by silver staining or Western immunoblotting using specific antibodies against the proteasome subunits. The 20S proteasome was also studied for its association with the 11S regulator by Western immunoblotting using an antibody to the regulator alfa subuniT., Results: T he purified proteasome was shown to have PGPH, trypsin-like and chymotrypsin-like activities. Furthermore, it incorporated the inducible subunits and was associated with the 11S regulator., Conclusions: The features we observed make renal cells susceptible to an over-expression of inflammatory response to immunological challenges.