Helena Marco

Long-term outcome of antineutrophil cytoplasmic antibody-associated small vessel vasculitis after renal transplantation

The survival after renal transplantation of patients with antineutrophil cytoplasmic antibody (ANCA)‐associated to systemic vasculitis is as good as in other diseases, although most of the reports are based on small numbers of patients. Furthermore, it is not known whether comorbidities (cardiovascular [CV] disease and cancer) are more frequent than in general population. We report our experience and the analysis of the published data on this topic. The outcome after transplantation in 49 patients with ANCA‐associated small vessel vasculitis was compared with a control group. The relapse rate of vasculitis was 0.01 per patient per year. Comparison with the control patients revealed no difference in long‐term outcome, CV mortality or incidence of malignancies. In the published literature, patients with ANCA at transplantation and with Wegeners granulomatosis are at greater risk of relapse. Taking our own results together with the review of the literature, we conclude that patient and graft survival rates compare favorably with those in control group that the recurrence rate is very low and that there is no increase in the incidence of cancer or in CV mortality. Patients with ANCA at transplantation and with Wegeners granulomatosis have a higher relapse rate.

Elevated factor H–related protein 1 and factor H pathogenic variants decrease complement regulation in IgA nephropathy

IgA nephropathy (IgAN), a frequent cause of chronic kidney disease worldwide, is characterized by mesangial deposition of galactose-deficient IgA1-containing immune complexes. Complement involvement in IgAN pathogenesis is suggested by the glomerular deposition of complement components and the strong protection from IgAN development conferred by the deletion of the CFHR3 and CFHR1 genes (ΔCFHR3-CFHR1). Here we searched for correlations between clinical progression and levels of factor H (FH) and FH-related protein 1 (FHR-1) using well-characterized patient cohorts consisting of 112 patients with IgAN, 46 with non-complement-related autosomal dominant polycystic kidney disease (ADPKD), and 76 control individuals. Patients with either IgAN or ADPKD presented normal FH but abnormally elevated FHR-1 levels and FHR-1/FH ratios compared to control individuals. Highest FHR-1 levels and FHR-1/FH ratios are found in patients with IgAN with disease progression and in patients with ADPKD who have reached chronic kidney disease, suggesting that renal function impairment elevates the FHR-1/FH ratio, which may increase FHR-1/FH competition for activated C3 fragments. Interestingly, ΔCFHR3-CFHR1 homozygotes are protected from IgAN, but not from ADPKD, and we found five IgAN patients with low FH carrying CFH or CFI pathogenic variants. These data support a decreased FH activity in IgAN due to increased FHR-1/FH competition or pathogenic CFH variants. They also suggest that alternative pathway complement activation in patients with IgAN, initially triggered by galactose-deficient IgA1-containing immune complexes, may exacerbate in a vicious circle as renal function deterioration increase FHR-1 levels. Thus, a role of FHR-1 in IgAN pathogenesis is to compete with complement regulation by FH.

Diagnostic Procedures and Rationale for Specific Therapies in Chronic Kidney Disease-Mineral and Bone Disorder

Chronic kidney disease (CKD) is associated with increased mortality. Non-traditional risk factors, such as mineral metabolism disturbances, seem to contribute to the unexpected high mortality rate. A chronic kidney disease-mineral bone disorder (CKD-MBD) has recently been defined as a systemic disorder manifested by one or a combination of abnormalities in bone biopsy, laboratory parameters, and/or vascular or other soft tissue calcifications. Recent research developments and new available treatments have all contributed to move the former treatment paradigm beyond the control of PTH. Thus, despite much of the advice given by different societies being just opinion-based evidence, the effect of different drugs on laboratory parameters, vascular calcification (VC) or survival may steer the choice of specific treatments. Aluminum and calcium-based phosphorus binders have been associated either with metal toxicity or progression of VC. Sevelamer hydrochloride has been related to an attenuation of the progression of VC and it has also been associated with improved survival at least in certain subgroups of dialysis patients. Lanthanum carbonate decreases phosphorus levels but its impact on surrogate or hard outcomes is not known. Selective vitamin D-receptor activators may have differential effects on VC, are associated with a survival advantage and thereby may have a best-fitted profile for CKD patients. On the other hand, calcimimetics markedly help to achieve current guidelines and ongoing clinical trials are evaluating hard outcomes. It is likely that a regimen combining several drugs might improve individual results. However, the utility of any new approach to CKD-MBD will need to be evaluated in prospective trials including thorough pharmacoeconomic analysis.

Therapeutic variability in adult minimal change disease and focal segmental glomerulosclerosis

Background Variability in the management of glomerulonephritis may negatively impact efficacy and safety. However, there are little/no data on actual variability in the treatment of minimal change disease (MCD)/focal segmental glomerulosclerosis (FSGS) in adults. We assessed Spanish practice patterns for the management of adult nephrotic syndrome due to MCD or FSGS. The absence of reasonably good evidence on treatment for a disease often increases the variability substantially. Identification of evidence–practice gaps is the first necessary step in the knowledge-to-action cyclical process. We aim to analyse the real clinical practice in adults in hospitals in Spain and compare this with the recently released Kidney Disease: Improving Global Outcomes clinical practice guideline for glomerulonephritis. Methods Participating centres were required to include all adult patients (age >18 years) with a biopsy-proven diagnosis of MCD or FSGS from 2007 to 2011. Exclusion criteria included the diagnosis of secondary nephropathy. Results We studied 119 Caucasian patients with biopsy-proven MCD (n = 71) or FSGS (n = 48) from 13 Spanish hospitals. Of these patients, 102 received immunosuppressive treatment and 17 conservative treatment. The initial treatment was steroids, except in one patient in which mycophenolate mofetil was used. In all patients, the steroids were given as a single daily dose. The mean duration of steroid treatment at initial high doses was 8.7 ± 13.2 weeks and the mean global duration was 38 ± 32 weeks. The duration of initial high-dose steroids was <4 weeks in 41% of patients and >16 weeks in 10.5% of patients. We did find a weak and negative correlation between the duration of whole steroid treatment in the first episode and the number of the later relapses (r = −0.24, P = 0.023). There were 98 relapses and they were more frequent in MCD than in FSGs patients (2.10 ± 1.6 versus 1.56 ± 1.2; P = 0.09). The chosen treatment was mainly steroids (95%). Only seven relapses were treated with another drug as a first-line treatment: two relapses were treated with mycophenolate and five relapses were treated with anticalcineurinics. A second-line treatment was needed in 29 patients (24.4%), and the most frequent drugs were the calcineurin inhibitors (55%), followed by mycophenolate mofetil (31%). Although cyclophosphamide is the recommended treatment, it was used in only 14% of the patients. Conclusions We found variation from the guidelines in the duration of initial and tapered steroid therapy, in the medical criteria for classifying a steroid-resistant condition and in the chosen treatment for the second-line treatment. All nephrologists started with a daily dose of steroids as the first-line treatment. The most frequently used steroid-sparing drug was calcineurin inhibitors. Cyclophosphamide use was much lower than expected.

Seasonal variations in the onset of positive and negative renal ANCA-associated vasculitis in Spain

Abstract Background The closure of long-standing gaps in our knowledge of aetiological factors behind anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitis (AAV) is a major challenge. Descriptive and analytical epidemiological studies can improve our understanding of environmental influences. Reported seasonal variations in AAV, mainly related to Wegeners disease, have shown an increasing number of cases in the winter months, which could be related to an extrinsic factor underlying infection. The objective of this paper was to study seasonal variations in AAV with respect to renal affectation diagnosed in Catalonia, Spain. Methods Two hundred and thirty-four patients diagnosed for renal AAV between 2001 and 2014 in eight hospitals in Catalonia were included in the study. We used medical records to retrospectively analyse the date of the first symptoms attributed to the AAV, ANCA subtypes, the degree of renal impairment and renal histology. Results Of the 234 patients studied, 49.2% were male and 50.8% female. For ANCA status, 8.5% were positive, 15.9% were proteinase-3-positive and 75.6% were myeloperoxidase-positive. In relation to histological classification, 17.8% were sclerotic, 11.7% focal, 38.8% crescentic and 31.7% mixed. Regarding seasonal distribution, we observed a clear seasonal periodicity with a significantly higher incidence of cases in the winter. Applying an Eigen decomposition, we observed a periodic fluctuation of frequencies around the annual cycle with peaks every 10–12 months, and higher incidence of AAV cases in February. Conclusions Our results confirm, in Catalonia, the seasonal periodicity of AAV with a higher incidence in the winter, as formerly described in the literature for other regions. An environmental factor, likely one that is infectious, may explain this finding.

Efficacy of mycophenolate treatment in adults with steroid-dependent/frequently relapsing idiopathic nephrotic syndrome

Abstract Background This study assessed the efficacy of therapy with mycophenolate (MF) and reduced doses of steroids in adults with steroid-dependent/frequently relapsing idiopathic nephrotic syndrome (SD/FR-INS). Methods Twenty-nine nephrotic patients (including 16 males and 13 females; mean age: 40 years, range: 18–74) were treated. Starting doses of MF were 2000 mg/day for mofetil MF (1500 mg/day in one patient) or 1440 mg/day for sodium MF. The initial prednisone (PDN) dose was 10 mg/day in 14 patients, 5 mg/day in two patients and no steroids in one patient. In the remaining 12 patients, moderate initial doses of PDN were administered (mean: 23.7 mg/day, range: 15–40), tapering to 10 mg/day after 1 month. Results Nephrotic syndrome remission was achieved in 27/29 cases (93.1%) (25 complete, 2 partial). Two patients showed resistance to the prescribed schedule. The first cycle of MF therapy was concluded in 20 patients after a mean (range) of 16.9 months (12–49). Maintenance of remission was observed in 11 of these 20 cases (55%) after a mean follow-up of 32.8 months (12–108). In nine patients with nephrotic syndrome relapse after tapering of MF (MF dependency), the same MF-PDN schedule was restarted, leading again to remission in all nine. The remaining seven MF-sensitive patients are still receiving their first therapeutic cycle. To date, the mean time under therapy in the 27 MF-sensitive patients is 38 months (4–216). Regarding complications, only minor digestive disorders and a slight decrease in blood haemoglobin levels were observed in a few patients. Conclusions MF plus reduced doses of PDN is an effective and well-tolerated therapy for adult SD/FR-INS. Though MF dependence is observed, its low toxicity could allow long periods of therapy if it is required to maintain nephrotic syndrome remission.