A quantum ruler for orbital magnetism in moiré quantum matter.

For almost a century, magnetic oscillations have been a powerful "quantum ruler" for measuring Fermi surface topology. In this study, we used Landau-level spectroscopy to unravel the energy-resolved valley-contrasting orbital magnetism and large orbital magnetic susceptibility that contribute to the energies of Landau levels of twisted double-bilayer graphene. These orbital magnetism effects led to substantial deviations from the standard Onsager relation, which manifested as a breakdown in scaling of Landau-level orbits. These substantial magnetic responses emerged from the nontrivial quantum geometry of the electronic structure and the large length scale of the moiré lattice potential. Going beyond traditional measurements, Landau-level spectroscopy performed with a scanning tunneling microscope offers a complete quantum ruler that resolves the full energy dependence of orbital magnetic properties in moiré quantum matter.

The relation between cognitive-behavioural responses to symptoms in patients with long term medical conditions and the outcome of cognitive behavioural therapy for fatigue - A secondary analysis of four RCTs.

BACKGROUND: Cognitive behavioural therapy (CBT) is effective in reducing fatigue across long-term conditions (LTCs). This study evaluated whether cognitive and behavioural responses to symptoms: 1) differ between LTCs and 2) moderate and/or mediate the effect of CBT on fatigue. METHOD: Data were used from four Randomized Controlled Trials testing the efficacy of CBT for fatigue in Chronic Fatigue Syndrome/ME (N = 240), Multiple Sclerosis (N = 90), Type 1 Diabetes Mellitus (N = 120) and Q-fever fatigue syndrome (N = 155). Fatigue severity, assessed with the Checklist Individual Strength, was the primary outcome. Differences in fatigue perpetuating factors, assessed with the Cognitive Behavioural Responses to Symptoms Questionnaire (CBRQ), between diagnostic groups were tested using ANCOVAs. Linear regression and mediation analyses were used to investigate moderation and mediation by CBRQ scores of the treatment effect. RESULTS: There were small to moderate differences in CBRQ scores between LTCs. Patients with higher scores on the subscales damage beliefs and avoidance/resting behaviour at baseline showed less improvement following CBT, irrespective of diagnosis. Reduction in fear avoidance, catastrophising and avoidance/resting behaviour mediated the positive effect of CBT on fatigue across diagnostic groups. DISCUSSION: The same cognitive-behavioural responses to fatigue moderate and mediate treatment outcome across conditions, supporting a transdiagnostic approach to fatigue.

Intermediate-term survival of robot-assisted versus open radical cystectomy for muscle-invasive and high-risk non-muscle invasive bladder cancer in The Netherlands.

BACKGROUND: Radical cystectomy with pelvic lymph node dissection is the recommended treatment in non-metastatic muscle-invasive bladder cancer (MIBC). In randomised trials, robot-assisted radical cystectomy (RARC) showed non-inferior short-term oncological outcomes compared with open radical cystectomy (ORC). Data on intermediate and long-term oncological outcomes of RARC are limited. OBJECTIVE: To assess the intermediate-term overall survival (OS) and recurrence-free survival (RFS) of patients with MIBC and high-risk non-MIBC (NMIBC) who underwent ORC versus RARC in clinical practice. METHODS AND MATERIALS: A nationwide retrospective study in 19 Dutch hospitals including patients with MIBC and high-risk NMIBC treated by ORC (n = 1086) or RARC (n = 386) between January 1, 2012 and December 31, 2015. Primary and secondary outcome measures were median OS and RFS, respectively. Survival outcomes were estimated using Kaplan-Meier curves. A multivariable Cox regression model was developed to adjust for possible confounders and to assess prognostic factors for survival including clinical variables, clinical and pathological disease stage, neoadjuvant therapy and surgical margin status. RESULTS: The median follow-up was 5.1 years (95% confidence interval ([95%CI] 5.0-5.2). The median OS after ORC was 5.0 years (95%CI 4.3-5.6) versus 5.8 years after RARC (95%CI 5.1-6.5). The median RFS was 3.8 years (95%CI 3.1-4.5) after ORC versus 5.0 years after RARC (95%CI 3.9-6.0). After multivariable adjustment, the hazard ratio for OS was 1.00 (95%CI 0.84-1.20) and for RFS 1.08 (95%CI 0.91-1.27) of ORC versus RARC. Patients who underwent ORC were older, had higher preoperative serum creatinine levels and more advanced clinical and pathological disease stage. CONCLUSION: ORC and RARC resulted in similar intermediate-term OS and RFS in a cohort of almost 1500 MIBC and high-risk NMIBC.

Predictors of postoperative cardiovascular complications up to 3 months after kidney transplantation.

BACKGROUND: Renal transplant patients have a high peri-operative risk for cardiovascular events. Pre-operative screening for cardiac ischaemia might lower this risk, but there are no specific guidelines. METHODS: We conducted a chart review for all renal transplants performed between January 2010 and December 2013. We collected data about patient characteristics, pre-operative cardiac evaluation before referral, diagnostic tests and interventions. Logistic regression analyses were then applied to relate these factors to the composite endpoint of cardiac death, myocardial infarction, coronary revascularisation or admission for heart failure within 3 months after transplantation. RESULTS: A total of 770 kidney transplants were performed in 751 patients. In 750 cases (97%) a referral to the cardiologist was made. Non-invasive ischaemia detection by myocardial perfusion scintigraphy, exercise stress test or dobutamine stress echocardiography was carried out in 631 cases (82%). Coronary angiography was performed in 85 cases, which revealed significant coronary artery disease in 19 cases. Prophylactic revascularisation was done in 7 cases. The incidence of the study endpoint was 8.6%. In multivariable regression analysis, age at transplantation, pre-transplant myocardial infarction or heart failure, post-operative decrease in haemoglobin and positive non-invasive ischaemia testing were significantly associated with the study endpoint. However, when analysed separately, none of the different non-invasive ischaemia detection modalities were related to the study endpoint. CONCLUSION: Especially those renal transplant candidates with a cardiac history carry a high risk for a cardiovascular event post-transplantation. Uniformity in cardiac screening of renal transplant candidates and better pre-operative preparation might lower this post-operative risk. Besides, post-transplant anaemia should be prevented.

Robust zero-energy modes in an electronic higher-order topological insulator.

Quantum simulators are essential tools for understanding complex quantum materials. Platforms based on ultracold atoms in optical lattices and photonic devices have led the field so far, but the basis for electronic quantum simulators is now being developed. Here, we experimentally realize an electronic higher-order topological insulator (HOTI). We create a breathing kagome lattice by manipulating carbon monoxide molecules on a Cu(111) surface using a scanning tunnelling microscope. We engineer alternating weak and strong bonds to show that a topological state emerges at the corner of the non-trivial configuration, but is absent in the trivial one. Different from conventional topological insulators, the topological state has two dimensions less than the bulk, denoting a HOTI. The corner mode is protected by a generalized chiral symmetry, which leads to a particular robustness against perturbations. Our versatile approach to designing artificial lattices holds promise for revealing unexpected quantum phases of matter.

Regulatory T cell features in chronic granulomatous disease.

Chronic granulomatous disease (CGD) is a primary immunodeficiency caused by mutations in any of the genes encoding the phagocyte nicotinamide adenine dinucleotide phosphate (NADPH) oxidase system, responsible for the production of reactive oxygen species (ROS). CGD is marked by invasive bacterial and fungal infections and by autoinflammation/autoimmunity, of which the exact pathophysiology remains elusive. Contributing factors include decreased neutrophil apoptosis, impaired apoptotic neutrophil clearance, increased proinflammatory protein expression and reduced ROS-mediated inflammasome dampening. We have explored a fundamentally different potential mechanism: it has been reported that macrophage-mediated induction of regulatory T cells (Tregs ) depends on ROS production. We have investigated whether numerical or functional deficiencies exist in Tregs of CGD patients. As the prevalence of autoinflammation/autoimmunity differs between CGD subtypes, we have also investigated Tregs from gp91phox -, p47phox - and p40phox -deficient CGD patients separately. Results show that Treg numbers and suppressive capacities are not different in CGD patients compared to healthy controls, with the exception that in gp91phox -deficiency effector Treg (eTreg ) numbers are decreased. Expression of Treg markers CD25, inducible T cell co-stimulator (ICOS), Helios, cytotoxic T lymphocyte antigen 4 (CTLA-4) and glucocorticoid-induced tumor necrosis factor receptor (GITR) did not provide any clue for differences in Treg functionality or activation state. No correlation was seen between eTreg numbers and patients' clinical phenotype. To conclude, the only difference between Tregs from CGD patients and healthy controls is a decrease in circulating eTregs in gp91phox -deficiency. In terms of autoinflammation/autoimmunity, this group is the most affected. However, upon culture, patient-derived Tregs showed a normal phenotype and normal functional suppressor activity. No other findings pointed towards a role for Tregs in CGD-related autoinflammation/autoimmunity.

Design and characterization of electrons in a fractal geometry.

The dimensionality of an electronic quantum system is decisive for its properties. In one dimension electrons form a Luttinger liquid and in two dimensions they exhibit the quantum Hall effect. However, very little is known about the behavior of electrons in non-integer, or fractional dimensions1. Here, we show how arrays of artificial atoms can be defined by controlled positioning of CO molecules on a Cu (111) surface2-4, and how these sites couple to form electronic Sierpinski fractals. We characterize the electron wave functions at different energies with scanning tunneling microscopy and spectroscopy and show that they inherit the fractional dimension. Wave functions delocalized over the Sierpinski structure decompose into self-similar parts at higher energy, and this scale invariance can also be retrieved in reciprocal space. Our results show that electronic quantum fractals can be artificially created by atomic manipulation in a scanning tunneling microscope. The same methodology will allow future study to address fundamental questions about the effects of spin-orbit interaction and a magnetic field on electrons in non-integer dimensions. Moreover, the rational concept of artificial atoms can readily be transferred to planar semiconductor electronics, allowing for the exploration of electrons in a well-defined fractal geometry, including interactions and external fields.

The assessment of field trials in GMO research around the world and their possible integration in field trials for variety registration.

Most regulations worldwide stipulate that a new genetically modified (GM) crop event has to be compared to its closest non-GM counterpart as a corner stone of the pre-market risk assessment. To this end the GM crop and its comparator should be grown in field trials for a phenotypic comparison as well as for subsequent detailed analysis of the composition of the two crop varieties. A more in-depth globally harmonised approach for the conduct of these field trials is lacking. Only a few countries have formulated detailed protocols for the set-up of GM field trials. In some countries, commercial non-GM reference varieties need to be included in a field study to compile reliable data that indicate the range of natural variation for the compounds tested at the specific location. Detailed analysis of pre-market assessment reports have so far not shown the added value of including these reference varieties in the field trials. In all cases where specific values were found to be outside of the range of the reference varieties, it proved possible to draw conclusions on the part of the pre-market risk assessment that relates to the compositional analysis, on the basis of already available compositional data. With the increasing quality of several databases on compositional data of a growing number of crop species, it seems unlikely that reference varieties will become more important on future occasions. It was furthermore investigated whether this part of the risk assessment can be related to field trial requirements for variety registration with the explicit intention of reducing the data burden on producers of new GM plant varieties. Field trials for variety registration so far include an assessment of phenotypic characteristics that do not cover safety aspects, with the exception of establishment of the glycoalkaloid content in potatoes in the Netherlands and Sweden. It may, however, under certain conditions be relatively easy to exchange data from compositional measurements between variety registration and GM testing procedures, thus laying a foundation for testing the feasibility of combining both pre-market assessment procedures in a single pre-market evaluation path.

Tumour-free margins in vulvar squamous cell carcinoma: Does distance really matter?

BACKGROUND: There is no consensus on the width of tumour-free margins after surgery for vulvar squamous cell carcinoma (VSCC). Most current guidelines recommend tumour-free margins of ≥8 mm. The aim of this study was to investigate whether a margin of <8 mm is associated with an increased risk of local recurrence in VSCC. METHODS: A meta-analysis of the available literature and a cohort study of 148 VSCC patients seen at a referral centre from 2000 to 2012 was performed. The primary end-point of the cohort study was a histologically confirmed ipsilateral local recurrence within 2 years after primary treatment in relation to the margin distance. RESULTS: Based on 10 studies, the meta-analysis showed that a tumour-free margin of <8 mm is associated with a higher risk of local recurrence compared to a tumour-free margin of ≥8 mm (pooled risk ratio, 1.99 [95% confidence interval {CI}: 1.13-3.51], p = 0.02). In the cohort study, we found no clear difference in the risk of local recurrence in the <8 versus ≥8 mm group; however, 40% of the patients in the <8 mm group received additional treatment. Tumour-positive margin was the only independent risk factor for local recurrence in the multivariable analysis (hazard ratio, 0.21 [95% CI: 0.08-0.55]). CONCLUSIONS: This work provides important data to question the commonly used 8-mm margin as a prognosticator for local recurrence. More research is needed to address the question of whether additional treatment improves the prognosis in patients with a tumour-free margin of <8 mm.

Simple and practical screening approach to identify HIV-infected individuals with depression or at risk of developing depression.

OBJECTIVES: Studies have shown that depression and other mental illnesses are under-diagnosed among HIV-infected individuals. The aim of this study was to evaluate the use of mental health history and questionnaire-based screening instruments to identify HIV-infected individuals at risk of depression. METHODS: The Beck Depression Inventory II (BDI-II) was used to assess the prevalence and severity of depressive symptoms among HIV-infected individuals attending two out-patient clinics in Denmark. HIV-infected individuals with a BDI-II score ≥ 20 were offered a clinical evaluation by a consultant psychiatrist. The BDI-II score was compared to the outcome of mental health history review, and to results obtained using the European AIDS Clinical Society (EACS) two-item depression screening tool. RESULTS: A total of 501 HIV-infected individuals were included in the study. Symptoms of moderate/major depression (BDI-II score ≥ 20) were observed in 111 patients (22%); 65 of these patients consulted a psychiatrist, of whom 71% were diagnosed with a co-existing disorder. The BDI-II score was compared to the outcome of a mental health history review, and to results obtained using the European AIDS Clinical Society (EACS) two-item depression screening tool. The two questions showed a sensitivity and specificity of 95% and 68%, respectively, for diagnosis of current depression or risk of depression. A previous psychiatric history and substance abuse were independently associated with an increased risk of depression. CONCLUSIONS: We suggest that the mental health of HIV-infected individuals should be reviewed and a "risk-flag" three-step approach should be used (1) to screen routinely with the two verbal questions suggested by the EACS, (2) to identify whether there is a risk of depression and then screen with the BDI-II, and (3) to identify whether there is still a risk and then perform a full evaluation and obtain an accurate psychiatric diagnosis by a psychiatrist.

Factors associated with risk of depression and relevant predictors of screening for depression in clinical practice: a cross-sectional study among HIV-infected individuals in Denmark.

OBJECTIVES: Depression and psychiatric disorders are frequent among HIV-infected individuals. The aim of this study was to determine the prevalence of depression and describe the psychiatric history of HIV-infected individuals in an out-patient clinic in Denmark and to identify factors of clinical importance that may be used to identify patients at risk of depression. METHODS: In 2013, 212 HIV-infected patients were included in a questionnaire study. We used the Beck Depression Inventory II (BDI-II) to assess the prevalence and severity of depressive symptoms. Patients with a BDI-II score ≥ 20 were offered a clinical evaluation by a consultant psychiatrist. Logistic regression was used to determine predictors associated with risk of depression. RESULTS: Symptoms of depression (BDI-II score ≥ 14) were observed in 75 patients (35%), and symptoms of moderate to major depression (BDI-II score ≥ 20) in 55 patients (26%). There was also a high prevalence of co-occurring mental illness. In a multivariate model, self-reported stress, self-reported perception that HIV infection affects all aspects of life, self-reported poor health, not being satisfied with one's current life situation, previous alcohol abuse, nonadherence to antiretroviral therapy and previously having sought help because of psychological problems were independently associated with risk of depression. CONCLUSIONS: Symptoms of depression and co-occurring mental illness are under-diagnosed and under-treated among HIV-infected individuals. We recommend that screening of depression should be conducted regularly to provide a full psychiatric profile to decrease the risk of depression and improve adherence and quality of life in this population.

Diagnostic value of a heart-type fatty acid-binding protein (H-FABP) bedside test in suspected acute coronary syndrome in primary care.

BACKGROUND: To determine the diagnostic accuracy of a rapid heart-type fatty acid-binding protein (H-FABP) test in patients suspected of acute coronary syndrome (ACS) in primary care. METHODS: General practitioners included 298 patients suspected of ACS. In all patients, whether referred to hospital or not, ECG and cardiac biomarker testing was performed. ACS was determined in accordance with international guidelines. Multivariate analysis was used to determine the value of H-FABP in addition to clinical findings. RESULTS: Mean patient age was 66 years (SD 14), 52% was female and 66 patients (22%) were diagnosed with ACS. The H-FABP bedside test was performed within 24h (median 3.1, IQR 1.5 to 7.1) after symptom onset. The positive predictive value (PPV) of H-FABP was 65% (95% confidence interval (CI) 50-78). The negative predictive value (NPV) was 85% (95% CI 80-88). Sensitivity was 39% (29-51%) and specificity 94% (90-96%). Within 6h after symptom onset, the PPV was 72% (55-84) and the NPV was 83% (77-88), sensitivity 43% (31-57%) and specificity 94% (89-97%). Adding the H-FABP test to a diagnostic model for ACS led to an increase in the area under the receiver operating curve from 0.66 (95% CI 0.58-0.73) to 0.75 (95% CI 0.68-0.82). CONCLUSION: The H-FABP rapid test provides modest additional diagnostic certainty in primary care. It cannot be used to safely exclude rule out ACS. The test can only be used safely in patients otherwise NOT referred to hospital by the GP, as an extra precaution not to miss ACS ('rule in').

Diagnosing acute coronary syndrome in primary care: comparison of the physicians' risk estimation and a clinical decision rule.

BACKGROUND: Diagnosing acute coronary syndrome (ACS) in a primary care setting poses a diagnostic dilemma for physicians. OBJECTIVE: We directly compared the diagnostic accuracy of a clinical decision rule (CDR) based on history taking and physical examination in suspected ACS with the risk estimates of the attending GP. METHODS: In a prospective multicenter study, patients suspected of ACS were included by the GP. GPs were asked to estimate the probability (0%-100%) of the presence of ACS. GPs collected patient data, but they were not aware of the CDR and did not score the patient accordingly. RESULTS: Two hundred and ninety-eight patients were included (52% female, mean age 66 years, 22% ACS). The area under the receiver operating characteristic (ROC) curve (AUC) was 0.75 [95% confidence interval (CI) 0.68-0.82] for the GP risk estimate and 0.66 (95% CI 0.58-0.73) for the CDR. There was an agreement between the risk estimation of the GP and a CDR in 51% and the prevalence of ACS in predefined low-, intermediate- and high-risk groups was similar for the GP and CDR estimates. In the low-risk group, according to the GP, four patients (8.2%) suffered an ACS. These four patients were all identified by the decision rule as high risk. CONCLUSIONS: The GP classified patients as ACS or no ACS more adequately than the CDR, judged by the AUC. However, the use of a CDR in patients that are considered at low risk for ACS by the GP could reduce the amount of missed myocardial infarctions.

Processing cord blood from premature infants into autologous red-blood-cell products for transfusion.

BACKGROUND AND OBJECTIVES: The use of umbilical cord blood (UCB) for transfusion purposes has gained interest the past years. UCB transfusion could serve premature infants, who often need transfusions early in life. MATERIAL AND METHODS: We investigated the suitability of different storage media. UCB was collected after 25 0/7--35 6/7 gestational weeks and centrifuged to concentrate red cells subsequently stored in saline-adenine-glucose-mannitol (SAGM), or in additive solution-3 (AS-3), or stored as whole blood in citrate-phosphate-dextrose-adenine-1. Quality parameters were measured at 7 day intervals during 35 days and compared to the standard RBC product. RESULTS: White-blood-cell- and platelet counts were higher in the UCB products. In the fractionated units, haemolysis remained below 1·0% in 64% after 14 days, and in 30% after 21 days. Storage in SAGM or AS-3 showed similar quality. Whole blood UCB showed better pH and haemolysis rates after 21 days. CONCLUSION: UCB can be processed into autologous products for premature infants. Shelf-life is limited to 14-21 days and compares unfavourably to stored whole blood. Considering the early transfusion needs in these infants, a short shelf-life would not be a practical objection.

How to recognize a suitable pancreas donor: a Eurotransplant study of preprocurement factors.

INTRODUCTION: Because of the increasing demand for pancreas transplantation, more marginal donors are offered to Eurotransplant. The aim of this study was to validate a donor quality score that would facilitate recognition of a suitable pancreas donor among all reported donors. MATERIALS AND METHODS: We analyzed all 3180 consecutively reported pancreas donors for the period between January 1, 2002 and June 30, 2005 and determined the influence of the preprocurement pancreas suitability score (P-PASS) on the acceptance of a pancreas. We defined a range and point weight for each variable based on clinical expertise and known literature. RESULTS: Multiple regression analysis using pancreas acceptance as an outcome variable identified P-PASS > or = 17 as a significant cutoff point (P < .001). Pancreata from donors with P-PASS > or = 17 were three times more likely to be refused. CONCLUSION: The donor score can help in screening for potential pancreas donors, where an ideal donor has a P-PASS < 17. Our data demonstrate that consideration of a combination of preprocurement factors can help identify a suitable pancreas donor. Therefore, we recommend that a pancreas donor score be calculated for each potential pancreas donor, and all donors with a P-PASS < 17 should be considered for pancreas donation.

Anti-oxidized low-density lipoprotein antibodies in myeloperoxidase-positive vasculitis patients preferentially recognize hypochlorite-modified low density lipoproteins.

Many patients surviving vasculitis are prone to accelerated atherosclerosis and often have enhanced levels of antibodies to oxidized low-density lipoprotein (oxLDL). To measure anti-oxLDL antibodies, oxidation of LDL is achieved with copper (Cu) or malondialdehyde (MDA). Because, in vivo, LDL may be oxidized with myeloperoxidase (MPO) or its product hypochlorite, we measured anti-hypochlorite LDL antibodies in patients with vasculitis, haemodialysis patients and healthy controls. A newly developed enzyme-linked immunosorbent assay (ELISA) was used to detect antibodies to oxLDL as modified by hypochlorite. Results are compared with data obtained by standard LDL oxidation using MDA-LDL or Cu-LDL as substrate. Results were compared between anti-neutrophil cytoplasmic antibodies (ANCA)-associated vasculitis (AAV) patients (n = 93), haemodialysis (HD) patients (n = 59) and healthy controls (HC; n = 43). Furthermore, patients with MPO-ANCA-associated vasculitis (n = 47) were compared with patients with proteinase 3 (PR3)-ANCA associated vasculitis (n = 46). Optimal cut-off points were determined by receiver operator characteristic (ROC) curve analysis. Anti-oxLDL antibodies are enhanced in AAV patients (MDA-LDL and hypochlorite-LDL) and in HD patients (hypochlorite-LDL), when compared to HC. Furthermore, patients with MPO-ANCA-associated vasculitis had higher levels of antibodies to hypochlorite-LDL than patients with PR3-ANCA-associated vasculitis. Our newly developed assay, in which hypochlorite-LDL is used as substrate, seems a more sensitive assay than traditional assays to measure oxLDL antibodies. Furthermore, our results suggest that enhanced MPO-mediated LDL oxidation occurs in patients with MPO-ANCA.

Antibodies against human 60 kDa heat shock protein are not associated with cardiovascular disease in patients with rheumatoid arthritis.

BACKGROUND: Rheumatoid arthritis is associated with an unexplained increased risk of cardiovascular disease (CVD). Antibodies against human 60 kDa heat shock protein (anti-HSP60) are associated with the presence and severity of CVD. OBJECTIVES: To investigate whether anti-HSP60 antibodies are associated with prevalent CVD in patients with rheumatoid arthritis. METHODS: In a nested case-control design, anti-HSP60 antibody levels were measured in the serum samples of 192 rheumatoid patients. In a regression analysis the association between prevalent CVD and anti-HSP60 antibodies was examined, along with the possible influence on this association of several demographic, rheumatoid arthritis, and CVD related variables. RESULTS: In a random sample of 326 patients with rheumatoid arthritis, 48 cases were identified who also suffered from CVD. Three controls per case with rheumatoid arthritis but without CVD (n = 144) were matched for sex, age, disease duration, and smoking habits. A regression analysis showed no significant association between prevalent CVD and anti-HSP60 antibodies (odds ratio = 1.00 (95% confidence interval, 0.997 to 1.004)). After correcting for possible confounding variables, still no association was found. CONCLUSIONS: In contrast to the general population, anti-HSP60 antibody titres are not associated with prevalent CVD in patients with rheumatoid arthritis. These findings could be the result of an altered immune response to HSP60 in rheumatoid arthritis.

Evaluation of a new fluorescent-enzyme immuno-assay for diagnosis and follow-up of ANCA-associated vasculitis.

In this study we have evaluated a new, fully automated fluorescent-enzyme immuno-assay (FEIA) for detection and quantification of anti-PR3 and anti-MPO ANCA in diagnosis and follow-up of ANCA-associated small vessel vasculitis (AAV). PR3- and MPO-ANCA were determined by FEIA technology in (1) sera of 87 consecutive patients with biopsy-proven, pauci-immune necrotizing crescentic glomerulonephritis (NCGN) and 72 controls; (2) 120 sera (60 patients with Wegener's granulomatosis and 60 controls) that were previously used in a multicentre comparison of direct and capture ELISAs for PR3-ANCA; (3) in samples preceding relapse in 23 PR3-AAV patients with and 23 matched PR3-AAV patients without relapse for prediction of relapses. PR3- and/or MPO-ANCA detection in pauci-immune NCGN by FEIA revealed an overall sensitivity of 82.8%. The FEIA specificity was 96% and 100% for PR3- and MPO-ANCA, respectively. The overall sensitivity of MPO- and PR3-ANCA could be increased to 88.5% by lowering the cut-off values without affecting the specificity (ROC-curve analysis), which is similar to a multistep ANCA procedure that combines indirect immunofluorescence with direct and capture ELISAs. The sensitivity for Wegener's granulomatosis (WG) of the PR3-ANCA FEIA (60%) was more comparable to direct ELISAs (64%) than to capture ELISAs (74%). A rise of 100% in ANCA level as measured by FEIA appeared optimal (ROC-curve) for prediction of relapses and such a rise was observed in 26 patients. In 18 of these 26 patients the rise was followed by a relapse (PPV 69%), whereas in 15 of the 20 patients without a rise no relapse was observed (NPV 75%). In conclusion, detection of PR3- and MPO-ANCA by FEIA has excellent performance in terms of diagnosis of AAV patients. Furthermore, detection of rises in PR3-ANCA by FEIA for prediction of relapses gives results comparable to other techniques.

Evaluation of antineutrophil cytoplasmic antibody seroconversion induced by minocycline, sulfasalazine, or penicillamine.

OBJECTIVE: Case reports have suggested that minocycline, sulfasalazine, and penicillamine are associated with antineutrophil cytoplasmic antibody (ANCA)-positive vasculitis. This study evaluated ANCA seroconversion due to these agents in serum samples prospectively collected in randomized, double-blind, controlled trials. METHODS: The sources of study sera were 3 clinical trials: 1) a 48-week trial of minocycline for early rheumatoid arthritis, with 64 patients receiving minocycline compared with 68 receiving placebo; 2) a 37-week trial of sulfasalazine for rheumatoid arthritis, with 51 receiving sulfasalazine compared with 38 receiving placebo; and 3) a 104-week trial of penicillamine for early systemic sclerosis, with 15 undergoing high-dose penicillamine treatment versus 12 receiving low-dose penicillamine. ANCA were measured in the baseline and study-end serum samples by indirect immunofluorescence (IIF) for perinuclear ANCA (pANCA) and cytoplasmic ANCA (cANCA) patterns, and by antigen-specific enzyme-linked immunosorbent assay (ELISA) for antibodies to myeloperoxidase (anti-MPO) and proteinase 3 (anti-PR3). Laboratory personnel were blinded to the group identity of the samples. ANCA results were interpreted using an ANCA scoring system that combines the results of IIF and ELISA testing. RESULTS: No patient in any of the active study drug groups demonstrated ANCA seroconversion according to the final interpretation of the combined IIF and ELISA results. Twelve of the 248 patients (5%) were positive for anti-MPO with pANCA at baseline. No subject was positive for anti-PR3 with cANCA. There were no findings suggestive of vasculitis in any of these patients. CONCLUSION: From our study results, there was no suggestion of ANCA seroconversion induced by minocycline, sulfasalazine, or penicillamine. However, these findings do not rule out the possibility of rare, sporadic cases of either ANCA seroconversion or true drug-induced vasculitis with these drugs.