Primary membranous nephropathy in the Italian region of Emilia Romagna: results of a multicenter study with extended follow-up.

BACKGROUND: Since primary membranous nephropathy is a heterogeneous disease with variable outcomes and multiple possible therapeutic approaches, all 13 Nephrology Units of the Italian region Emilia Romagna decided to analyze their experience in the management of this challenging glomerular disease. METHODS: We retrospectively studied 205 consecutive adult patients affected by biopsy-proven primary membranous nephropathy, recruited from January 2010 through December 2017. The primary outcome was patient and renal survival. The secondary outcome was the rate of complete remission and partial remission of proteinuria. Relapse incidence, treatment patterns and adverse events were also assessed. RESULTS: Median (IQR) follow-up was 36 (24-60) months. Overall patient and renal survival were 87.4% after 5 years. At the end of follow-up, 83 patients (40%) had complete remission and 72 patients (35%) had partial remission. Among responders, less than a quarter (23%) relapsed. Most patients (83%) underwent immunosuppressive therapy within 6 months of biopsy. A cyclic regimen of corticosteroid and cytotoxic agents was the most commonly used treatment schedule (63%), followed by rituximab (28%). Multivariable analysis showed that the cyclic regimen significantly correlates with complete remission (odds ratio 0.26; 95% CI 0.08-0.79) when compared to rituximab (p < 0.05). CONCLUSIONS: In our large study, both short- and long-term outcomes were positive and consistent with those published in the literature. Our data suggest that the use of immunosuppressive therapy within the first 6 months after biopsy appears to be a winning strategy, and that the cyclic regimen also warrants a prominent role in primary membranous nephropathy treatment, since definitive proof of rituximab superiority is lacking.

Podocyte-Related Mechanisms Underlying Survival Benefit of Long-Term Angiotensin Receptor Blocker.

We previously found that short-term treatment (week 8 to 12 after injury) with high-dose angiotensin receptor blocker (ARB) induced the regression of existing glomerulosclerosis in 5/6 nephrectomy rats. We therefore assessed the effects of long-term intervention with ARB vs. nonspecific antihypertensives in this study. Adult rats underwent 5/6 nephrectomy and renal biopsy 8 weeks later. The rats were then divided into three groups with equivalent renal function and glomerular sclerosis and treated with high-dose losartan (ARB), nonspecific antihypertensive triple-therapy (TRX), or left untreated (Control) until week 30. We found that blood pressure, serum creatinine levels, and glomerulosclerosis were lower at sacrifice in ARB and TRX vs. Control. Only ARB reduced proteinuria and maintained the density of WT-1-positive podocytes. Glomerular tufts showed more double-positive cells for CD44, a marker of activated parietal epithelial cells, and synaptopodin after ARB vs. TRX or Control. ARB treatment reduced aldosterone levels. ARB-treated rats had significantly improved survival when compared with TRX or Control. We conclude that both long-term ARB and triple-therapy ameliorate progression, but do not sustain the regression of glomerulosclerosis. ARB resulted in the superior preservation of podocyte integrity and decreased proteinuria and aldosterone, linked to increased survival in the uremic environment.

Secondary amyloidosis in autoinflammatory diseases and the role of inflammation in renal damage.

The release of proinflammatory cytokines during inflammation represents an attempt to respond to injury, but it may produce detrimental effects. The inflammasome is a large, multiprotein complex that drives proinflammatory cytokine production in response to infection and tissue injury; the best-characterized inflammasome is the nod-like receptor protein-3 (NLRP3). Once activated, inflammasome leads to the active form of caspase-1, the enzyme required for the maturation of interleukin-1beta. Additional mechanisms bringing to renal inflammatory, systemic diseases and fibrotic processes were recently reported, via the activation of the inflammasome that consists of NLRP3, apoptosis associated speck-like protein and caspase-1. Several manuscripts seem to identify NLRP3 inflammasome as a possible therapeutic target in the treatment of progressive chronic kidney disease. Serum amyloid A (SAA), as acute-phase protein with also proinflammatory properties, has been shown to induce the secretion of cathepsin B and inflammasome components from human macrophages. SAA is a well recognised potent activator of the NLRP3. Here we will address our description on the involvement of the kidney in autoinflammatory diseases driven mainly by secondary, or reactive, AA amyloidosis with a particular attention on novel therapeutic approach which has to be addressed in suppressing underlying inflammatory disease and reducing the SAA concentration.

Renal involvement in secondary amyloidosis of Muckle-Wells syndrome: marked improvement of renal function and reduction of proteinuria after therapy with human anti-interleukin-1ß monoclonal antibody canakinumab.

Muckle-Wells syndrome (MWS) is a rare hereditary autoinflammatory disorder characterized by recurrent urticaria-like skin rashes, arthralgias, conjunctivitis, hypoacusia, and risk of reactive AA amyloidosis due to the progressive accumulation of amyloid fibrils in different organs. Its genetic defect lies in mutations in the NLRP3 gene, encoding the cryopyrin protein, and resulting in interleukin (IL)-1ß oversecretion. Renal involvement, in terms of proteinuria or renal insufficiency, can be observed in up to 25% of patients. Herein, we describe our experience with two Caucasian patients, father and son, aged 52 and 26 years, respectively, heterozygous for both V198M and R260W NLRP3 mutations who had AA amyloid deposits on renal biopsy. The fully human monoclonal antibody canakinumab, providing selective and prolonged IL-1ß blockade, was administered in both patients every 60 days over a period of 18 months. This treatment allowed to obtain amazing results: a rapid disappearance of any clinical symptoms, the stable normalization of serum amyloid-A and, furthermore, a marked improvement of glomerular filtration rate and proteinuria with no adverse events. Our data, though limited to only two patients, emphasize that therapeutic intervention with canakinumab, suppressing both inflammation and IL-1ß-mediated manifestations, can contribute to improve kidney function in MWS with overt renal amyloidosis.

Treatment of dyslipidemia in chronic kidney disease: Effectiveness and safety of statins.

Several cardiovascular (CV) risk factors may explain the high rate of CV death among patients with chronic kidney disease (CKD). Among them both traditional and uremia-related risk factors are implicated and, moreover, the presence of kidney disease represents "per se" a multiplier of CV risk. Plasma lipid and lipoprotein profiles are changed in quantitative, but above all in qualitative, structural, and functional ways, and lipoprotein metabolism is influenced by the progressive loss of renal function. Statin therapy significantly reduces cholesterol synthesis and both CV morbidity and mortality either directly, by reducing the lipid profile, or via pleiotropic effects; it is supposed to be able to reduce both the progression of CKD and also proteinuria. These observations derive from a post-hoc analysis of large trials conducted in the general population, but not in CKD patients. However, the recently published SHARP trial, including over 9200 patients, either on dialysis or pre-dialysis, showed that simvastatin plus ezetimibe, compared with placebo, was associated with a significant low-density lipoprotein cholesterol reduction and a 17% reduction in major atherosclerotic events. However, no benefit was observed in overall survival nor in preserving renal function in patients treated. These recent data reinforce the conviction among nephrologists to consider their patients at high CV risk and that lipid lowering drugs such as statins may represent an important tool in reducing atheromatous coronary disease which, however, represents only a third of CV deaths in patients with CKD. Therefore, statins have no protective effect among the remaining two-thirds of patients who suffer from sudden cardiac death due to arrhythmia or heart failure, prevalent among CKD patients. The safety of statins is demonstrated in CKD by several trials and recently confirmed by the largest SHARP trial, in terms of no increase in cancer incidence, muscle pain, creatine kinase levels, severe rhabdomyolysis, hepatitis, gallstones and pancreatitis; thus confirming the handiness of statins in CKD patients. Here we will review the latest data available concerning the effectiveness and safety of statin therapy in CKD patients.