IntroductionPhase-contrast magnetic resonance imaging (PC-MRI) is a non-invasive method used to compute blood flow velocity and volume, alongside several derivative hemodynamic parameters. Renal blood flow (RBF) assessment is important for the diagnosis and monitoring of a range of renal diseases, in which it decreases since earliest stages. The aim of this study was to elucidate PC-MRI potential as biomarker of renal perfusion and function in a cohort of patients with C3 Glomerulopathy (C3G) or Immune-Complex Membranoproliferative Glomerulonephritis (IC-MPGN).MethodsMRI and clinical data used in this study were collected from 7 patients with C3G or IC-MPGN, in the context of a non-contrast enhanced (NCE) MRI subproject of a pharmacological clinical trial (NCT03723512). All patients underwent NCE-MRI at two time points (before and after 1 year of treatment with ACH-0144471) in addition to clinical evaluation, laboratory testing, GFR measurement by Iohexol clearance, and baseline kidney biopsy. Cardiac-gated 2D PC velocity-sensitive sequence was acquired in breath-hold on each renal artery to investigate renal perfusion. Total RBF was computed as sum of left and right renal artery blood flow. Renal plasma flow (RPF) was computed as RBF * (1 – hematocrit); renal vascular resistance (RVR) was computed as mean arterial pressure divided by RPF; and filtration fraction (FF) was computed as GFR divided by RPF. Peritubular interstitial volume was quantified on biopsy specimens stained with PAS by point counting. The correlation between PC-MRI parameters and clinical and histological findings were investigated by Spearman’s correlation.ResultsAlbumin to creatinine ratio (A/C) at all available time points was negatively associated with RBF, RPF, and FF (rho=-0.86, p<0.001; rho=-0.84, p<0.001; and rho=-0.6, p=0.043, respectively), while positively correlated with RVR (rho=0.88, p<0.001), as shown in Figure 1A. Measured GFR (mGFR) was positively associated with RBF, RPF, and FF (rho=0.87, p<0.001; rho=0.68, p=0.019; and rho=0.85, p<0.001, respectively), while negatively correlated with RVR (rho=-0.89, p<0.001), as shown in Figure 1B. Moreover, peritubular interstitial volume was negatively correlated with RBF (rho=-0.81, p=0.022) and showed a trend towards negative association with RPF (rho=-0.52, p=0.2) and positive association with RVR (rho=0.65, p=0.083).View Large Image Figure ViewerDownload Hi-res image Download (PPT)ConclusionsThe strong significant correlation found between PC-MRI-based parameters and clinical and histological findings, despite the rather limited number of patients, highlights PC-MRI potential to assess and stage renal function damage in patients with C3G or IC-MPGN. Future larger studies are needed to confirm current findings.No conflict of interest IntroductionPhase-contrast magnetic resonance imaging (PC-MRI) is a non-invasive method used to compute blood flow velocity and volume, alongside several derivative hemodynamic parameters. Renal blood flow (RBF) assessment is important for the diagnosis and monitoring of a range of renal diseases, in which it decreases since earliest stages. The aim of this study was to elucidate PC-MRI potential as biomarker of renal perfusion and function in a cohort of patients with C3 Glomerulopathy (C3G) or Immune-Complex Membranoproliferative Glomerulonephritis (IC-MPGN).

RATIONALE & OBJECTIVE:Primary membranoproliferative glomerulonephritis (MPGN) is a rare glomerulopathy characterized by complement dysregulation. MPGN progresses rapidly to kidney failure when it is associated with nephrotic syndrome. We assessed the effects of C5 convertase blockade in patients with MPGN and terminal complement activation.STUDY DESIGN:Prospective off-on-off-on open-label clinical trial.SETTING & PARTICIPANTS:Consenting patients with immune complex-mediated MPGN (n=6) or C3 glomerulonephritis (n=4) with sC5b-9 (serum complement membrane attack complex) plasma levels>1,000ng/mL and 24-hour proteinuria with protein excretion>3.5g identified from the Italian Registry of MPGN and followed up at the Istituto di Ricerche Farmacologiche Mario Negri IRCCS (Bergamo, Italy) between March 4, 2014, and January 7, 2015.INTERVENTION:Anti-C5 monoclonal antibody eculizumab administered during 2 sequential 48-week treatment periods separated by one 12-week washout period.OUTCOMES:Primary outcome was change in 24-hour proteinuria (median of 3 consecutive measurements) at 24 and 48 weeks.RESULTS:Median proteinuria decreased from protein excretion of 6.03 (interquartile range [IQR], 4.8-12.4) g/d at baseline to 3.74 (IQR, 3.2-4.4) g/d at 24 weeks (P=0.01) and to 5.06 (IQR, 3.1-5.8) g/d (P=0.006) at 48 weeks of treatment, recovered toward baseline during the washout period, and did not significantly decrease thereafter. Hypoalbuminemia, dyslipidemia, and glomerular sieving function improved during the first treatment period. 3 patients achieved partial remission of nephrotic syndrome and all had undetectable C3 nephritic factors before treatment. Mean measured glomerular filtration rate was 69.7±35.2 versus 87.4±55.1 and 75.8±42.7 versus 76.6±44.1mL/min/1.73m2 at the start versus the end of the first and second treatment periods, respectively, among all 10 study participants. Unlike C3, sC5b-9 plasma levels normalized during both treatment periods and recovered toward baseline during the washout in all patients.LIMITATIONS:Single-arm design, small sample size.CONCLUSIONS:Eculizumab blunted terminal complement activation in all patients with immune complex-mediated MPGN or C3 glomerulonephritis and nephrotic syndrome, but persistently reduced proteinuria in just a subgroup.TRIAL REGISTRATION:Registered in the EU Clinical Trials Register with study no. 2013-003826-10.

Eray Eroglu, Ismail Kocyigit, Ahmet Kaynar, Derya Kocer, Gokmen Zararsiz, Ruslan Bayramov, Hakan Imamoglu, Murat Sipahioglu, Bulent Tokgoz, Munis Dundar, Oktay Oymak Biostatistics, Erciyes University, Kayseri, Turkey, Genetic, Erciyes University, Kayseri, Turkey, Internal Medicine, Erciyes University, Kayseri, Turkey, Nephrology, Erciyes University, Kayseri, Turkey, Radiology, Erciyes University, Kayseri, Turkey, Nephrology, Erciyes University Faculty of Medicine, Kayseri, Turkey and Biochemistry, Kayseri Training and Research Hospital, Kayseri, Turkey

Rare diseases (RD) are an important bench test case for healthcare services organization. This for both moral and ethical aspects which implies knowing how to cope with the needs of a vulnerable sector of population. At the same time RD its a challenge for healthcare service organizations, which are called to respond to particularly emphatic individual requirements. The study has been developed on administrative database of the Regional health care system of Lombardia Region, containing all the services provided to resident population and the related costs (or tariffs recognized by the the Regional System). The analysis includes all the citizen benefiting of an exemption from copayments due to a rare diseases condition. The RHS (regional health care system) perspective has been adopted. The analysis covered 44,548 subjects with copayment exemption due to RD. The prevalence (2012) was equal to 0.46% of the resident population, with a significant gender difference: 0.39% for males and 0.53 % for females. The average annual expenditure per rare diseased patient amounts to € 5,003.1, a value approximately comparable to the average one for patients with at least two chronic conditions (€ 4,500.2). In terms of gender the figure for women (€ 3,539.3) is significantly lower than that for males (€ 6,856.6). The total impact on RHS is € 222.9 M, equal to 1.21% of regional spending. Patients with ultra rare disease are characterized by costs (€ 6,953.6 pro capita) significantly above the average. the research give some original insight on the prevalence and economic impact of RD patients in a large population. It permits to appreciate the potential organizational and economic impact od RD patients, especially of those with an ultra-rare condition, as well as financial risk for the local health care units due to prevalence concentration.

Objective: Since Takayasu arteritis (TA) may present in a different manner in different countries, an Italian collaborative study group was established (ITAKA – Italian Takayasu Arteritis Study Group) with the purpose to identify a significant number of Italian patients with TA and to evaluate its clinical features, angiographic findings, and treatment. Methods: We identified TA patients using the administrative data of all hospital discharges occurred in Italy between 1995 and 1997 and the Italian TA registry. The diagnosis of TA was made according to the 1990 ACR criteria. Only patients who had been followed during the previous 12 months were included in the study. 104 patients with TA were studied. Data on clinical features, angiographic and laboratory findings, pregnancies, medical and surgical treatment were recorded. Results: 99% of our patients were Caucasians and females (87.5%) were most frequently affected. The median age at disease onset was 29.2 years. The age <15 years and an erythrocyte sedimentation rate (ESR) <30 mm/h were associated to a higher probability of a delay in diagnosis ≥2 years. The most common clinical finding at diagnosis was a bruit (90%). 71% of the patients had at disease onset constitutional/musculoskeletal symptoms. 61 patients had a full aortography: stenosis was the most frequent lesion (93%), followed by occlusion (57%), dilatation (16%) and aneurysm (7%). The number of lesions per patient increased with disease duration. Claudication of the limbs, Raynaud's phenomenon and distal cutaneous hypothermia were more frequent in patients with lesions of subclavian and/or iliac arteries (78.4% vs. 40.0%; p = 0.02). Headache, dizziness, syncopal attacks, convulsions, TIA and stroke were more frequent in patients with lesions of vertebral and/or carotid arteries (62.8% vs. 22.2%; p = 0.005). Hypertension was more frequent in patients with renal artery stenosis (92.0% vs. 30.6%; p<0.0001). The yearly incidence of pregnancies decreased from 8.2 every 100 fertile women before the onset of TA to 2.8 after the onset of the disease. We registered a trend towards an increasing in the percentage of spontaneous abortion after the onset (11% vs. 21%, p = 0.6). Glucocorticoids were the most frequently used drugs, being prescribed to 86% of patients, while cytotoxic agents were prescribed to 54%. 52 patients underwent to at least one surgical procedure: percutaneous transluminal angioplasty (PTA) was performed in 54% of the patients, by-pass in 42%, PTA with stent in 21%, aneurysm repair and aortic valve replacement in 8% each. Conclusion: The main socio-demographic and clinical characteristics of our large series of Italian patients with TA are similar to those described in a Japanese nationwide survey. These results suggest that TA could not be so different between Eastern and Western countries, as it has been often claimed.

Thrombotic thrombocytopenic purpura (TTP) is a rare disorder of small vessels that is associated with deficiency of the von Willebrand factor-cleaving protease, ADAMTS13. The presence of anti-ADAMTS13 autoantibodies is considered a factor predisposing to relapses. Despite close monitoring and intensive plasma treatment, in these patients acute episodes are still associated with substantial morbidity and mortality rates, and the optimal therapeutic option should be prevention of relapses. This study was conducted in a patient with recurrent TTP due to high titers of ADAMTS13 inhibitors, who used to have 2 relapses of TTP a year. The study compared the standard treatment plasma exchange with rituximab. Results documented that plasma exchange had only a small transient effect on ADAMTS13 activity and inhibitors; on the contrary, prophylaxis with rituximab was associated with disappearance of anti-ADAMTS13 antibodies, a progressive recovery of protease activity, and it allowed the patient to maintain a disease-free state during a more than 2-year follow-up.

OBJECTIVE:Takayasu's arteritis (TA) is a rare vasculitis. The Italian Takayasu's Arteritis study group was established with the aim to describe a large cohort of patients.METHODS:Data were collected by means of an ad hoc form. Demographic information, clinical history, vascular findings, treatment, risk factors, and comorbidities were analyzed.RESULTS:Data of 104 patients were collected. The median delay in diagnosis was 15.5 months (range 0-325 months). Age at onset <15 years was associated with a higher probability, whereas elevated erythrocyte sedimentation rate with a lower probability, of a delay in diagnosis. The majority of patients experienced nonspecific signs and symptoms indicative of an inflammatory disease in the early phase. Among vascular involvement, stenosis was the most frequent lesion, being present in 93% of patients, followed by occlusion (57%), dilatation (16%), and aneurysm (7%). Glucocorticoids were the mainstay of treatment in our series; however, treatment with cytotoxic agents was required in about half of the patients. Fifty-two patients underwent at least 1 surgical procedure. The main indications for intervention were renal vascular hypertension, cerebral hypoperfusion, and limb claudication.CONCLUSION:As with many rare diseases, delay in diagnosis is an important issue for patients with TA. The increasing occurrence of vascular lesions along with the disease progression put to question the long-term effectiveness of contemporary treatment. These data may be helpful in increasing physicians' awareness to prevent diagnosis delay, update guidelines, and plan future research projects.

Whether measurement of ADAMTS13 activity may enable physicians to distinguish thrombotic thrombocytopenic purpura (TTP) from hemolytic uremic syndrome (HUS) is still a controversial issue. Our aim was to clarify whether patients with normal or deficient ADAMTS13 activity could be distinguished in terms of disease manifestations and multimeric patterns of plasma von Willebrand factor (VWF). ADAMTS13 activity, VWF antigen, and multimeric pattern were evaluated in patients with recurrent and familial TTP (n = 20) and HUS (n = 29). Results of the collagen-binding assay of ADAMTS13 activity were confirmed in selected samples by testing the capacity of plasma to cleave recombinant VWF A1-A2-A3. Most patients with TTP had complete or partial deficiency of ADAMTS13 activity during the acute phase, and in some the defect persisted at remission. However, complete ADAMTS13 deficiency was also found in 5 of 9 patients with HUS during the acute phase and in 5 patients during remission. HUS patients with ADAMTS13 deficiency could not be distinguished clinically from those with normal ADAMTS13. In a subgroup of patients with TTP or HUS, the ADAMTS13 defect was inherited, as documented by half-normal levels of ADAMTS13 in their asymptomatic parents, consistent with the heterozygous carrier state. In patients with TTP and HUS there was indirect evidence of increased VWF fragmentation, and this occurred also in patients with ADAMTS13 deficiency. In conclusion, deficient ADAMTS13 activity does not distinguish TTP from HUS, at least in the recurrent and familial forms, and it is not the only determinant of VWF abnormalities in these conditions.

The aim of the present study was to clarify whether factor H mutations were involved in genetic predisposition to hemolytic uremic syndrome, by performing linkage and mutation studies in a large number of patients from those referred to the Italian Registry for Recurrent and Familial HUS/TTP. PCR and Western blot analyses were conducted to characterize the biochemical consequences of the mutations. Five mutations in the factor H gene were identified. Three, identified in two families and in a sporadic case, are heterozygous point mutations within the most C-terminal short consensus repeat 20 (SCR20) of factor H, resulting in single amino acid substitutions. The other two mutations introduce premature stop codons that interrupt the translation of factor H. A heterozygous nonsense mutation was identified in SCR8 in one family, and a homozygous 24-bp deletion within SCR20 was identified in a Bedouin family with a recessive mode of inheritance. Reverse transcription-PCR analysis of cDNA from peripheral blood leukocytes from the Bedouin family showed that the deletion lowered factor H mRNA levels. Although heterozygous mutations were associated with normal factor H levels and incomplete penetrance of the disease, the homozygous mutation in the Bedouin family resulted in severe reduction of factor H levels accompanied by very early disease onset. These data provide compelling molecular evidence that genetically determined deficiencies in factor H are involved in both autosomal-dominant and autosomal-recessive hemolytic uremic syndrome and identify SCR20 as a hot spot for mutations in the disease. The mutations identified here give an important hint to the relevance of the C-terminus of factor H in the control of the alternative complement activation pathway.

BACKGROUND:Takayasu arteritis is a rare form of chronic inflammatory disease of the large arterial vessels. Some patients do not respond to steroids or immunosuppressant drugs.OBJECTIVE:To evaluate the effect of mycophenolate mofetil in patients with severe Takayasu arteritis.DESIGN:Case series.SETTING:Clinical Research Center for Rare Diseases in Bergamo, Italy.PATIENTS:Three patients with Takayasu arteritis.INTERVENTION:Mycophenolate mofetil (2 g/d) given orally in two divided doses.MEASUREMENTS:Clinical evaluation and assessment of leukocyte counts were done weekly. Vascular lesions were assessed by using Doppler ultrasonography.RESULTS:All patients showed clinical benefit, and two resumed work after months of inactivity. Patients were also able to taper and discontinue steroid use. Mycophenolate mofetil was well tolerated, and no signs of toxicity were observed.CONCLUSIONS:Mycophenolate mofetil may be an alternative to steroids and cytotoxic agents in patients with Takayasu arteritis. Before results of controlled trials become available, mycophenolate mofetil should be considered only for patients who do not improve or stabilize with conventional therapy.

BACKGROUND:In patients with Takayasu arteritis, circulating lymphocytes are activated, and histological findings indicate that cell-mediated immunity plays an important role in the pathogenetic sequence leading to vascular lesions.METHODS AND RESULTS:To delineate the profile of inflammatory and chemoattractant cytokines involved in T-cell activation in Takayasu arteritis, we measured by ELISA serum levels of interleukin (IL)-6, IL-1beta, and RANTES in 18 patients. Subsequently, we wanted to establish whether any of these molecules could be used as a marker to monitor the clinical course of the disease and to predict disease exacerbations. We found that all patients with Takayasu arteritis studied during an active phase of the disease have increased serum concentration of IL-6 compared with healthy control subjects (P<0.01). Enhanced IL-6 serum levels paralleled disease activity to the extent that its serum concentrations were comparable to those of control subjects when patients were studied in remission. RANTES concentrations were also higher than normal in the serum of all patients with Takayasu arteritis (P<0.01) studied during an active phase of the disease. RANTES serum levels tended to normalize in remission, but values remained higher than those of control subjects (P<0.05). In contrast, serum concentrations of IL-1beta were below the detection limit of ELISA in both healthy subjects and all patients with Takayasu arteritis. A positive correlation was found between either IL-6 (rho=0.705, P<0.01) or RANTES (rho=0.607, P<0.05) serum level and disease activity.CONCLUSIONS:The close correlation of serum IL-6 and RANTES levels with disease activity suggests that these cytokines contribute to vasculitic lesions in Takayasu arteritis and raises the possibility that their monitoring in serum helps clinicians find adequate treatment adjustments in individual patients.

Renal clearance of inulin is the best available indicator of GFR but cannot be used routinely for clinical purposes and is also difficult to perform for clinical investigation when repeated measurements are required. The aim of this study was to find a reliable alternative to inulin clearance that would allow one to avoid the use of radioactivity and problems related to the continuous infusion of the marker. The plasma clearance of unlabeled iohexol, a nonionic contrast agent, was used. Forty-one patients (creatinine clearance 6 to 160 mL/min per 1.73 m2) underwent simultaneous measurements of renal clearance of inulin and plasma clearance of iohexol. Iohexol was given as a single iv dose, and blood samples were drawn up to 600 min after the administration. Iohexol concentrations (by HPLC) were analyzed by a two-compartment, open-model system. A highly significant correlation between the plasma clearance of iohexol and the renal clearance of inulin over a wide range of GFR values was found. By analyzing the data with a simplified method that uses a one-compartment model corrected with the Bröchner-Mortensen formula, an excellent correlation with the inulin clearance was also observed. When only patients with moderate to severe renal failure were considered, a significant correlation between the two methods was found. A further comparison between GFR determined with iohexol and iopromide, a new low-osmolarity, low-viscosity contrast medium, was also performed in a subgroup of patients.(ABSTRACT TRUNCATED AT 250 WORDS)

Glucocorticoids have a major role in the treatment of glomerular diseases. Despite recent advances in understanding of their mechanism of action, very few studies have addressed the relative advantage of the wide range of different dose regimens employed in clinical practice. We studied the effects of methylprednisolone given intravenously for three consecutive days at the doses of 1 mg/kg (group 1, N = 7; group 2, N = 5), 5 mg/kg (group 3, N = 5) or 15 mg/kg (group 4, N = 6) on total blood peripheral leukocytes and on lymphocyte subsets in patients with glomerular diseases, and investigated whether such effects were a function of the drug concentration in the blood. Since glucocorticoids have an inhibitory effect on the formation of eicosanoids in different cells, we also investigated in the same patients the effect of 1 and 15 mg/kg methylprednisolone on systemic and renal eicosanoid synthesis. Results of pharmacokinetic study showed that the three different doses of methylprednisolone we used resulted in major differences in patient's exposure to the drug, and within the same dose there was a great individual variability. By contrast the three different doses of methylprednisolone induced a comparable drop in the absolute number of lymphocytes six hours after the first injection of methylprednisolone, while 24 hours later blood lymphocyte counts returned to the pre-injection values in all patients. Analysis of lymphocyte subsets showed a selective decrease in the number of circulating CD4+ and CD8+ cells six hours after methylprednisolone which was comparable in the four groups of patients studied. As for the effect of methylprednisolone on systemic and renal eicosanoid synthesis in patients with glomerular diseases, 1 and 15 mg/kg were equally unable to reduce thromboxane A2 (TxA2) and prostaglandin E2 (PGE2) release by circulating polimorphonuclear cells (PMNs). By contrast, methylprednisolone partially inhibited eicosanoid synthesis by PMNs in vitro. Consistent with the data on PMNs, urinary excretion of TxA2 and prostacyclin (PGI2) metabolites were unaltered by the different doses of methylprednisolone. By contrast urinary PGE2 was markedly and significantly reduced in patients given 15 but not 1 mg/kg. We conclude that 1 mg/kg methylprednisolone given to patients with glomerular diseases has the same effect on peripheral total blood leukocyte count and lymphocyte subsets than 5 and 15 mg/kg. The same is true for eicosanoid synthesis by PMNs. Renal synthesis of PGE2 is inhibited by 15 mg/kg but not by 1 mg/kg.(ABSTRACT TRUNCATED AT 400 WORDS)