Novel biomarkers and pathophysiology of membranous nephropathy: PLA2R and beyond.

Research on membranous nephropathy truly exploded in the last 15 years. This happened because of the application of new techniques (laser capture microdissection, mass spectrometry, protein G immunoprecipitation, arrays) to the study of its pathogenesis. After the discovery of PLA2R as the major target antigen, many other antigens were identified and others are probably ongoing. Clinical and pathophysiology rebounds of new discoveries are relevant in terms of diagnosis and prognosis and it is time to make a first assessment of the innovative issues. In terms of classification, target antigens can be divided into: 'membrane antigens' and 'second wave' antigens. The first group consists of antigens constitutionally expressed on the podocyte membrane (as PLA2R) that may become a target of an autoimmune process because of perturbation of immune-tolerance. 'Second wave' antigens are antigens neo-expressed by the podocyte or by infiltrating cells after a stressing event: this allows the immune system to produce antibodies against them that intensify and maintain glomerular damage. With this abundance of target antigens it is not possible, at the moment, to test all antibodies at the bedside. In the absence of this possibility, the role of histological evaluation is still irreplaceable.

End-proximal tubule phosphate concentration increases as GFR falls in humans: measurement by means of a lithium clearance-based methodology.

BACKGROUND: Microscopic nephrocalcinosis secondary to intratubular calcium phosphate (CaP) precipitation is thought to accelerate progression to end-stage renal failure in chronic kidney diseases. In phosphorus (P)-loaded uninephrectomized rats, intratubular CaP crystal formation and progressive tubular damage occurred when end-proximal tubule P concentration (ePTpc) increased above a threshold level. METHODS: We have calculated ePTpc in humans by urine P and creatinine concentration, with the end-proximal tubule fluid volume calculated either as lithium (Li) clearance (ePTpc-Li) or as a fixed 0.7 fraction of glomerular filtration rate (GFR), as published (ePTpc-70). Healthy people undergoing living transplant kidney donation before (DON-pre, n = 70) and after (DON-post, n = 64) nephrectomy and 25 patients with stage 2-5 CKD were investigated while on regular free diet. RESULTS: ePTpc showed a stepwise increase with decreasing functional renal mass (DON-pre 2.51 ± 0.99 and 1.56 ± 0.47 mg/dL for ePTpc-Li and -70 calculation, respectively; DON-post 3.43 ± 1.14 and 2.18 ± 0.44;  CKD 5.68 ± 3.30 and 3.00 ± 1.30, P < .001 for all); ePTpc was inversely correlated with Ccr and directly with PTH, fractional P excretion and excretion (UpV) corrected for GFR (P < .001 for all), but not with Pp. ePTpc-Li and ePTpc-70 were significantly correlated (r = 0.62, P < .001), but ePTpc-70 was lower than the corresponding ePTpc-Li. Levels of ePTpc increased above a suggested dangerous threshold when daily UpV/GFR was higher than about 10 mg/mLCcr. CONCLUSIONS: ePTpc progressively increases in humans as functional renal mass falls independently from plasma P levels. Main determinants of ePTpc rise are GFR fall, degree of phosphaturia per unit GFR and P intake corrected for GFR. It may become a novel, potentially useful, indicator to guide management of CKD patients.

Eculizumab prevents thrombotic microangiopathy in patients with atypical haemolytic uraemic syndrome in a long-term observational study.

BACKGROUND: Eculizumab, a terminal complement inhibitor, is approved for atypical haemolytic uraemic syndrome (aHUS) to inhibit complement-mediated thrombotic microangiopathy (TMA). METHODS: In five parent studies, eculizumab effectively prevented TMA and improved renal and haematologic outcomes in patients with aHUS; therefore, these patients could enrol in this long-term, prospective, observational and multicentre study. The primary endpoint was the TMA manifestation rate off and on eculizumab post-parent study. Post hoc analyses evaluated rates during labelled versus non-labelled dosing regimens, and in those with versus without identified complement abnormalities. Serious targeted treatment-emergent adverse events (TEAEs) were evaluated. RESULTS: Of 87 patients in the current study, 39 and 76 had off- and on-treatment periods, respectively; 17 (44%) with off periods reinitiated eculizumab. TMA manifestation rate per 100 patient-years was 19.9 off and 7.3 on treatment [hazard ratio (HR), 4.7; P = 0.0008]; rates were highest off treatment and lowest during labelled regimens. TMA manifestations with hospitalizations/serious AEs occurred more frequently off versus on treatment. TMA rates were higher among patients with identified complement abnormalities (HR, 4.5; P = 0.0082). Serious targeted TEAEs occurred at similar rates off and on treatment. CONCLUSIONS: As expected, patients with aHUS have increased risk of TMA manifestations after discontinuation of eculizumab or in the setting of non-labelled eculizumab dosing. Collectively, results show that maintaining eculizumab treatment minimizes risk of TMA, particularly in patients with identified complement abnormalities. Future studies are needed to further characterize TMA and longer term outcomes on labelled or non-labelled eculizumab regimens and after discontinuation of treatment.

Outcomes in patients with atypical hemolytic uremic syndrome treated with eculizumab in a long-term observational study.

BACKGROUND: There are limited long-term outcome data in eculizumab-treated patients with atypical hemolytic uremic syndrome (aHUS). We report final results from the largest prospective, observational, multicenter study of patients with aHUS treated with eculizumab. METHODS: Patients with aHUS who participated in any of five parent eculizumab trials and received at least one eculizumab infusion were eligible for enrollment in a long-term follow-up study. Rates of thrombotic microangiopathy (TMA) manifestations off versus on eculizumab were evaluated. Additional endpoints included change from baseline estimated glomerular filtration rate (eGFR), long-term renal outcomes, and serious targeted treatment-emergent adverse events. RESULTS: Among 93 patients (0-80 years of age), 51 (55%) remained on eculizumab and 42 (45%) discontinued; for those who discontinued, 21 (50%) reinitiated therapy. Patients who reinitiated eculizumab had similar baseline clinical characteristics to patients who remained on eculizumab, with higher likelihood of genetic/autoimmune complement abnormalities, more prior TMAs, and longer disease course versus those who did not reinitiate. Mean eGFR improved rapidly and remained stable for up to 6 years on eculizumab. In patients who discontinued, there was a trend toward decreasing renal function over time from discontinuation. Additionally, off-treatment TMA manifestation rates were higher in those aged < 18 years at diagnosis, with identified genetic/autoimmune complement abnormalities, or history of multiple TMAs prior to eculizumab initiation. The safety profile was consistent with previous studies. Three definite and one possible meningococcal infections related to eculizumab were reported and resolved with treatment. Three deaths unrelated to eculizumab were reported. CONCLUSIONS: The current study confirms the efficacy and safety of eculizumab in aHUS, particularly with regard to long-term renal function and TMA events. Pediatric age at disease onset and presence of genetic or autoimmune complement abnormalities are risk factors for TMA events off treatment. Overall, patients who discontinue eculizumab may be at risk for additional TMA manifestations and renal function decreases. Discontinuation of eculizumab, with careful monitoring, is an option in select patients with consideration of patient preference, organ function normalization, and risk factors for relapse, including mutational analysis, age of onset, and history of multiple TMA episodes. TRIAL REGISTRATION: ClinicalTrials.gov NCT01522170 , January 31, 2012.

Extracorporeal blood purification techniques in children with hyper-inflammatory syndromes: a clinical overview.

Data on clinical applications of blood purification techniques in children are scarce. The aim of this review is to offer a clinical overview, as complete as possible, on blood purification in children with hyper-inflammatory syndromes (HS). A review of the literature using the PubMed, EMBASE, Web of Science, and Scopus databases, on the most recent data about blood purification in children was conducted until June 2018. Except for three randomized controlled trials (RCTs) on plasma exchange, no RCTs, but only observational studies or case reports were found regarding other blood purification techniques in children. High-volume hemofiltration in two non-randomized trials did not significantly reduce 28-day mortality in children. PE was not associated with reduced mortality in pediatric patients with septic shock, but the small number of patients enrolled is an important limitation. The use of polymixin B and other adsorbing columns in children with septic shock and HS is increasing, but results are still limited by the observational nature of the studies. Based on the low-level of available evidence, no conclusions can be drawn regarding the efficacy and safety of blood purification in children. Further research with more clinically robust data is needed to determine the impact of different extracorporeal blood purification techniques in this pediatric population.

Design optimization through thermomechanical finite-element analysis of a hybrid piston-clamped anvil cell for nuclear magnetic resonance experiments.

The investigation of materials under extreme pressure conditions requires high-performance cells whose design invariably involves trade-offs between the maximum achievable pressure, the allowed sample volume, and the possibility of real-time pressure monitoring. With a newly conceived hybrid piston-clamped anvil cell, we offer a relatively simple and versatile system, suitable for nuclear magnetic resonance experiments up to 4.4 GPa. Finite-element models, taking into account mechanical and thermal conditions, were used to optimize and validate the design prior to the realization of the device. Cell body and gaskets were made of beryllium-copper alloy and the pistons and pusher were made of tungsten carbide, while the anvils consist of zirconium dioxide. The low-temperature pressure cell performance was tested by monitoring in situ the pressure-dependent 63Cu nuclear-quadrupole-resonance signal of Cu2O.

Maxillary molar healing after treatment of an uninstrumented canal with a novel root canal procedure: a case report.

A major cause for endodontic failure is the inability to treat all anatomy. Studies report endodontic retreatments contain 42% missed canals. This case illustrates dentin preservation of a molar with an uninstrumented mesiobuccal-3 canal revealed post-GentleWave Procedure. Efficient cleaning and disinfection with maintained healing to 18 months is demonstrated.

First experience on bilirubin removal with a hemoadsorption column (Lixelle®) in a child with cardiogenic liver injury.

INTRODUCTION: Hyperbilirubinemia may have deleterious effects on many organs, even after the neonatal age. Blood purification is effective in the treatment of hyperbilirubinemia. Recently some reports suggest the potential role of hemoadsorption columns in this setting. METHODS: We present the case of a 6-year-old child with severe hyperbilirubinemia due to congestive liver dysfunction, complicated by persistent inflammation, immunosuppression and catabolism syndrome (PICS). The patient was treated with a hemoadsorption column (Lixelle®) in combination with continuous veno-venous hemodiafiltration (CVVHDF). RESULTS: During treatment, a significant and rapid decrease in total bilirubin (TB) and other indices of cholestasis was observed. Furthermore, a progressive reduction in the inflammatory biomarkers (Procalcitonin, C-reactive protein) occurred. These results persisted at the discontinuation of therapy. CONCLUSIONS: To our knowledge this is the first case in which hemoadsorption with the Lixelle® adsorbing column in combination with CVVHDF has been used to manage pediatric hyperbiliribinemia secondary to cardiogenic liver injury.

Terminal Complement Inhibitor Eculizumab in Adult Patients With Atypical Hemolytic Uremic Syndrome: A Single-Arm, Open-Label Trial.

BACKGROUND: Atypical hemolytic uremic syndrome (aHUS) is a rare genetic life-threatening disease of chronic uncontrolled complement activation leading to thrombotic microangiopathy (TMA) and severe end-organ damage. Eculizumab, a terminal complement inhibitor approved for aHUS treatment, was reported to improve hematologic and renal parameters in 2 prior prospective phase 2 studies. This is the largest prospective study of eculizumab in aHUS to date, conducted in an adult population. STUDY DESIGN: Open-label single-arm phase 2 trial. SETTING & PARTICIPANTS: Patients 18 years or older with aHUS (platelet count <150 × 10(3)/µL, hemoglobin ≤ lower limit of normal, lactate dehydrogenase ≥1.5 × upper limit of normal [ULN], and serum creatinine ≥ ULN) were included in this multicenter multinational study. INTERVENTION: Intravenous eculizumab (900mg/wk for 4 weeks, 1,200mg at week 5 and then every 2 weeks) for 26 weeks. OUTCOMES & MEASUREMENTS: Primary end point was complete TMA response within 26 weeks, defined as hematologic normalization (platelet count ≥150 × 10(3)/µL, LDH ≤ ULN), and preservation of kidney function (<25% serum creatinine increase from baseline), confirmed by 2 or more consecutive measurements obtained 4 or more weeks apart. RESULTS: 41 patients were treated; 38 (93%) completed 26 weeks of treatment. 30 (73%) were included during their first TMA manifestation. 30 (73%) had complete TMA response. Platelet counts and estimated glomerular filtration rates increased from baseline (P<0.001). All 35 patients on baseline plasma exchange/plasma infusion discontinued by week 26. Of 24 patients requiring baseline dialysis, 5 recovered kidney function before eculizumab initiation and 15 of the remaining 19 (79%) discontinued dialysis during eculizumab treatment. No patients lost existing transplants. Quality-of-life measures were significantly improved. Two patients developed meningococcal infections; both recovered, and 1 remained on eculizumab treatment. LIMITATIONS: Single-arm open-label design. CONCLUSIONS: Results highlight the benefits of eculizumab in adult patients with aHUS: improvement in hematologic, renal, and quality-of-life parameters; dialysis discontinuation; and transplant protection.

The Report-AGE project: a permanent epidemiological observatory to identify clinical and biological markers of health outcomes in elderly hospitalized patients in Italy.

BACKGROUND: Italy is expected to experience the largest growth in persons ≥65 years (>20% by 2020). This demographic shift allows for geriatric research on predictive clinical and biological markers of outcomes related to frailty, re-hospitalization and mortality. AIMS: To describe rationale and methods of the Report-AGE study project of acute care patients in Italian National Research Center on Aging (INRCA) research hospitals. METHODS: Report-AGE study is a large observational study on health conditions and outcomes of hospitalized elderly patients (≥65 years). The primary objective of the study is to create a high-level data resource of demographics, comprehensive geriatric assessments, clinical and diagnostic information, as well as biological and molecular markers in all older patients admitted to INRCA Hospitals. Assessments in physical and nutritional parameters, co-morbid health conditions, and associations with frailty parameters are ongoing in older hospitalized adults following an acute event. Study collection began in September 2011. RESULTS: Up to date, there are 3479 patients ≥65 years (mean age: 85 ± 7years) with 1543 men and 1936 women enrolled. Data have been recorded regarding functional and clinical parameters before, during hospital admission and at discharge. Data collection for primary outcome analyses related to re-hospitalization and mortality is estimated for September 2016. DISCUSSION: This study aims at collecting precise clinical data, comprehensive geriatric assessment, risk factors, and biological data from acute care patients. Data will also be used to identify mechanisms underlying frailty in this specific population. CONCLUSION: This study provides a descriptive epidemiological collection of the health conditions of older in-patients.

Body composition markers in older persons with COPD.

BACKGROUND: Body composition has been shown to be correlated with physical performance, but data in older persons with diverse chronic diseases are lacking. OBJECTIVE: We aimed at investigating the associations of body composition to gait speed and nutritional status of older people in different stages of chronic obstructive pulmonary disease (COPD). DESIGN, SETTING AND SUBJECTS: Cross-sectional analysis of data from Pulmonary Rehabilitation Geriatric Unit at INRCA in Casatenovo, Italy including 132 consecutively admitted COPD patients (mean age: 75 years) with data on body composition, walking speed and respiratory parameters. METHODS: Body mass parameters were assessed using bioelectrical impedance analysis. Pulmonary function tests included spirometry and arterial blood gases. Differences among body composition markers were compared according to gender. Separate multivariate linear regression models with gait speed as the dependent variable were used to test for independent associations with body composition markers after adjusting for multiple confounders. RESULTS: Walking speed deteriorated with increasing severity of COPD. Men were heavier and had more lean mass than women. Participants in the fastest gait tertile were younger, had lower body mass index and fat mass (FM); higher lean-to-fat ratio and albumin levels and better respiratory function (FEV1, FVC) compared with those in the slower tertiles. Total body FM was an independent determinant of walking speed, while fat-free mass and lean-to-fat ratio were not. CONCLUSIONS: Excess body fat may be harmful for physical functioning among elders with COPD.

Micromethod for quantification of cinacalcet in human plasma by liquid chromatography-tandem mass spectrometry using a stable isotope-labeled internal standard.

BACKGROUND: Cinacalcet hydrochloride is a calcimimetic agent indicated for the treatment of secondary hyperparathyroidism in dialysis-dependent patients with chronic kidney disease. In the context of a pharmacokinetic (PK)/pharmacodynamic study of cinacalcet in dialysis-dependent chronic kidney disease children with secondary hyperparathyroidism, we describe the development and validation of a new, rapid, simple, and economical liquid chromatography-tandem mass spectrometry (LC-MS/MS) micromethod for quantifying cinacalcet plasma concentrations. METHODS: Cinacalcet was analyzed in 50-µL plasma samples over a wide range of concentrations (0.1-100 ng/mL) by LC-MS/MS after protein precipitation and addition of deuterated cinacalcet as the internal standard. Cinacalcet was quantified using selective reaction monitoring of the specific transition m/z 358.1 > 155.1, with the 361.1 > 158.1 transition used for the internal standard. The suitability of the assay for clinical PK studies was evaluated using data from a pilot PK study in a pediatric patient. RESULTS: The overall turnaround time for the assay was 20 minutes. The lower limit of quantification of the method was 0.1 ng/mL. Intraassay imprecision and inaccuracy for quality control samples ranged from 2.8% to 9% and 100% to 102%, respectively. Interassay imprecision and inaccuracy ranged from 6.9% to 8.5% and 99% to 103%, respectively. The overall recovery ranged from 90% to 106%. No ion suppression due to matrix effects was found with different preanalytical conditions, such as hemolysis, lipemia, and hyperuricemia. CONCLUSIONS: This LC-MS/MS micromethod provides high specificity, precision, and accuracy for rapid quantification of cinacalcet plasma concentrations, and it is suitable for application in pediatric PK studies; it also has potential for use in the establishment of target ranges and ultimately routine therapeutic drug monitoring to optimize cinacalcet dosing.

Lymphocele after renal transplantation, a medical complication.

After 50 years, the incidence of lymphocele and lymphorrhea associated with renal transplantation remains substantially high in spite of more accurate surgical technique, reduction of other complications and improvement of general outcomes. The data from the literature point to the allograft as the source of increased lymph production, which in spite of an accurate hilar lymphatics ligature, can find a transcapsular outlet. Subclinical and clinical graft rejection and inflammation greatly enhance lymph production and leakage. This mechanism may partially mediate the effects of some immunosuppressive drugs on the incidence of lymphocele.

Practical management problems of chronic obstructive pulmonary disease in the elderly: acute exacerbations.

PURPOSE OF REVIEW: Acute exacerbations of chronic obstructive pulmonary disease (ECOPDs) have numerous causes and are associated with increased mortality and hospitalization, especially in older patients. The urgent need to identify and enable timely treatment of ECOPDs is a necessity for physicians worldwide. This review will highlight the causes and optimal combinations of available treatments for such events in older populations. RECENT FINDINGS: The exact definition of exacerbations is lacking; however, it is agreed that such events are considered episodes of worsening of symptoms, leading to morbidity and death. The aging process is a consistent determinant for ECOPD events and is associated with worsening of COPD stages. The incidence of ECOPD rises across the worsening stages of COPD. Studies have shown that the frequency of exacerbations increases with age and correlated clinical outcomes are poorer than in younger patients. The risk of mortality has also been shown to be significantly higher after a hospital admission following an acute exacerbation. At the moment, the need to rapidly and correctly treat acute exacerbations is crucially important in the rapidly growing elderly population. SUMMARY: ECOPDs are extremely dangerous events for older patients with severe stages of COPD. There is an urgent need to identify risk factors, identify tolerable treatment guidelines and manage acute exacerbations in older patients with COPD.

Does concealed chronic kidney disease predict survival of older patients discharged from acute care hospitals?

We aimed at verifying whether unrecognized chronic kidney disease (CKD) (i.e., reduced estimated glomerular filtration rate in spite of normal serum creatinine) has prognostic significance in an unselected population of older patients discharged from 11 acute care hospitals located throughout Italy. Our series consisted of 396 participants aged 70 and older. Estimated glomerular filtration rate (eGFR) was calculated by the Modification of Diet in Renal Disease (MDRD) study equation. We compared three groups: Normal renal function (normal serum creatinine levels and normal eGFR), concealed (normal serum creatinine levels and reduced eGFR), or overt (increased creatinine levels and reduced eGFR) renal failure. The relationship between renal function and 1-year mortality was evaluated using Kaplan-Meier curves and Cox regression analysis including potential confounders. Overall, 56 patients died over a cumulative follow-up time of 335 months, with an estimated incidence rate of 16.7/100 person-year (PY). The corresponding figures in patients with normal renal function, concealed CKD, and overt CKD were 9.8/100 PY (95% CI, 5.7-15.7), 28.3/100 PY (95% CI, 13.6-52.1), and 23.0 (95% CI, 15.4-33.0), respectively (log rank test p = 0.006). According to the fully adjusted model, both concealed (hazard ratio [HR], 2.35; 95% CI, 1.09-6.01) and overt CKD (HR, 2.09; 95% CI, 1.05-5.34) were significantly associated with the outcome. Concealed CKD contributes to profile the elderly patient at greater risk of death after being discharged from acute care medical wards. If confirmed in broader populations, this finding might have both clinical and epidemiological implications.