Anti-cyclic citrullinated peptide antibodies in rheumatoid arthritis: relation with clinical features, cytokines and HLA-DRB1

En el presente estudio se examinó la especificidad y la sensibilidad de los anticuerpos antipéptidos citrulinados cíclicos (CCP) en pacientes latinoamericanas con artritis reumatoidea (AR), así como su relación con la actividad de la enfermedad, manifestaciones extraarticulares (MEA), síntesis de citocinas (IL-4, IL-10, IL-12, TNF-? e IFN-?) y factor reumatoideo (FR) IgM e IgA, y con el polimorfismo del HLA-DRB1. Se examinaron 79 pacientes con AR (69 con AR establecida y 10 con AR temprana sin previo tratamiento), 56 pacientes con espondilitis anquilosante (EA), 25 con lupus eritematoso sistémico (LES), 50 con síndrome de Sjögren primario (SSp) y diez individuos sanos. De las 69 pacientes con AR establecida, 36 fueron reevaluadas 2 años después. La actividad de la AR se examinó según los criterios del Colegio Americano de Reumatología. Los anticuerpos anti-CCP2, el FR y los niveles de citocinas se determinaron mediante inmunoensayo, y la genotipificación del HLA se llevó a cabo por reacción en cadena de la polimerasa utilizando mezclas de iniciadores específicos. Los anticuerpos anti-CCP se observaron en 96% de los pacientes con AR en la primera evaluación y en 86% en la segunda (p=0,12), sin modificación significativa en los valores (131±58,7 vs. 130,6±67,1 UI). Su sensibilidad y especificidad global fue de 94% y 92%, respectivamente, pero cuando sólo se consideraron los niveles altos (>60 UI) fueron de 84% y 95%, respectivamente. La razón de probabilidades (RP) positiva fue de 12 y la RP negativa de 0,06. El valor predictivo (VP) positivo fue de 87% y el VP negativo de 96%. Los anticuerpos anti-CCP se observaron en 12% de los pacientes con LES y con SSp, en 2% de los de EA y en 10% de los controles sanos. En los pacientes con AR no se asociaron con la actividad de la enfermedad, MEA y alelos del HLA-DRB1. Tampoco se observaron correlaciones significativas entre sus valores y los niveles de citocinas. En conclusión, los anticuerpos anti-CCP tienen un interés diagnóstico para la AR en nuestra población, pero su utilidad en el seguimiento clínico es limitada y su síntesis es independiente del HLA-DRB1 y no se correlacionan con niveles de citocinas Th1/Th2.The specificity and sensitivity of anti-cyclic citrullinated peptide antibodies (anti-CCP) was examined in Latin-American patients with rheumatoid arthritis (RA). The variables considered included: 1) relation with the activity of disease, 2) extra-articular manifestations (EAM), 3) synthesis of cytokines (IL-4, IL-10, IL-12, TNF-alpha, and IFN-gamma) and IgM and IgA rheumatoid factor (RF), and 4) the association with HLA-DRB1 polymorphism. Seventy-nine RA patients were assessed (69 with established RA, and 10 with recent-onset RA not receiving any treatment), 56 with ankylosing spondylitis (AS), 25 with systemic lupus erythematosus (SLE), 50 with primary Sjögren's syndrome (pSS), and 10 healthy individuals. Of the 69 patients with established RA, 36 were reexamined 2 years later. The activity of the RA was measured by criteria adopted by the American College of Rheumatology. Anti-CCP2, RF and cytokines levels were determined by ELISA. HLA genotypes were established by first, PCR sequence amplification using sequence-specific primers and then, complete sequencing of the product. Anti-CCP antibodies were observed in 96% of patients with RA during the first evaluation and in 86% at the second evaluation (p = 0.12). No significant change in antibody titre was observed between the two evaluations (131 +/- 58.7 and 130.6 +/- 67.1 IU, respectively). The overall sensitivity and specificity was 94% and 92%, respectively; however, at titres > 60 IU, the values were 84% and 95%, respectively. The anti-CCP likelihood ratio positive test was 12 and the likelihood ratio negative test was 0.06. The positive predictive value was 87%, and the negative predictive value was 96%. Anti-CCP antibodies were observed in 12% of SLE and pSS patients, in 2% of AS patients, and in 10% of healthy controls. In RA patients, these antibodies were not associated with the activity of disease, EAM or HLA-DRB1 alleles; no significant correlation was observed between antibody titre and cytokines level. Although anti-CCP antibodies have potential as a diagnostic tool for RA, they are not useful for monitoring clinical activity or predicting the clinical course of disease. Antibody synthesis is HLA-DRB1 independent and not correlated with Th1/Th2 cytokines

Evaluación de la fatiga en pacientes con artritis psoriásica y su asociación con otras variables de la enfermedad

Objetivo: evaluar la frecuencia de fatiga en pacientes con APs y su asociación con otras variables de la enfermedad

Identification of clinical phenotypes of peripheral involvement in patients with spondyloarthritis, including psoriatic arthritis: a cluster analysis in the worldwide ASAS-PerSpA study

OBJECTIVE: To identify clusters of peripheral involvement according to the specific location of peripheral manifestations (ie, arthritis, enthesitis and dactylitis) in patients with spondyloarthritis (SpA) including psoriatic arthritis (PsA), and to evaluate whether these clusters correspond with the clinical diagnosis of a rheumatologist. METHODS: Cross-sectional study with 24 participating countries. Consecutive patients diagnosed by their rheumatologist as PsA, axial SpA or peripheral SpA were enrolled. Four different cluster analyses were conducted: one using information on the specific location from all the peripheral manifestations, and a cluster analysis for each peripheral manifestation, separately. Multiple correspondence analyses and k-means clustering methods were used. Distribution of peripheral manifestations and clinical characteristics were compared across the different clusters. RESULTS: The different cluster analyses performed in the 4465 patients clearly distinguished a predominantly axial phenotype (cluster 1) and a predominantly peripheral phenotype (cluster 2). In the predominantly axial phenotype, hip involvement and lower limb large joint arthritis, heel enthesitis and lack of dactylitis were more prevalent. In the predominantly peripheral phenotype, different subgroups were distinguished based on the type and location of peripheral involvement: a predominantly involvement of upper versus lower limbs joints, a predominantly axial enthesitis versus peripheral enthesitis, and predominantly finger versus toe involvement in dactylitis. A poor agreement between the clusters and the rheumatologist's diagnosis as well as with the classification criteria was found. CONCLUSION: These results suggest the presence of two main phenotypes (predominantly axial and predominantly peripheral) based on the presence and location of the peripheral manifestations

Prevalence and distribution of peripheral musculoskeletal manifestations in spondyloarthritis including psoriatic arthritis: results of the worldwide, cross-sectional ASAS-PerSpA study

Objectives To characterise peripheral musculoskeletal involvement in patients with spondyloarthritis (SpA) including psoriatic arthritis (PsA), across the world. Methods Cross-sectional study with 24 participating countries. Patients with a diagnosis of axial SpA (axSpA), peripheral SpA (pSpA) or PsA according to their rheumatologist were included. The investigators were asked which diagnosis out of a list of six (axSpA, PsA, pSpA, inflammatory bowel disease-associated SpA, reactive arthritis or juvenile SpA (Juv-SpA)) fitted the patient best. Peripheral manifestations (ie, peripheral joint disease, enthesitis, dactylitis and root joint disease), their localisation and treatments were evaluated. Results A total of 4465 patients were included (61% men, mean age 44.5 years) from four geographic areas: Latin America (n=538), Europe plus North America (n=1677), Asia (n=975) and the Middle East plus North Africa (n=1275). Of those, 78% had ever suffered from at least one peripheral musculoskeletal manifestation; 57% had peripheral joint disease, 44% had enthesitis and 15% had dactylitis. Latin American had far more often peripheral joint disease (80%) than patients from other areas. Patients with PsA had predominantly upper limb and small joint involvement (52%). Hip and shoulder involvement was found in 34% of patients. The prevalence of enthesitis ranged between 41% in patients with axSpA and 65% in patients with Juv-SpA. Dactylitis was most frequent among patients with PsA (37%). Conclusion These results suggest that all peripheral features can be found in all subtypes of SpA, and that differences are quantitative rather than qualitative. In a high proportion of patients, axial and peripheral manifestations coincided. These findings reconfirm SpA clinical subtypes are descendants of the same underlying disease, called SpA.Pathophysiology and treatment of rheumatic disease

Identification of clinical phenotypes of peripheral involvement in patients with spondyloarthritis, including psoriatic arthritis: a cluster analysis in the worldwide ASAS-PerSpA study

Objective To identify clusters of peripheral involvement according to the specific location of peripheral manifestations (ie, arthritis, enthesitis and dactylitis) in patients with spondyloarthritis (SpA) including psoriatic arthritis (PsA), and to evaluate whether these clusters correspond with the clinical diagnosis of a rheumatologist. Methods Cross-sectional study with 24 participating countries. Consecutive patients diagnosed by their rheumatologist as PsA, axial SpA or peripheral SpA were enrolled. Four different cluster analyses were conducted: one using information on the specific location from all the peripheral manifestations, and a cluster analysis for each peripheral manifestation, separately. Multiple correspondence analyses and k-means clustering methods were used. Distribution of peripheral manifestations and clinical characteristics were compared across the different clusters. Results The different cluster analyses performed in the 4465 patients clearly distinguished a predominantly axial phenotype (cluster 1) and a predominantly peripheral phenotype (cluster 2). In the predominantly axial phenotype, hip involvement and lower limb large joint arthritis, heel enthesitis and lack of dactylitis were more prevalent. In the predominantly peripheral phenotype, different subgroups were distinguished based on the type and location of peripheral involvement: a predominantly involvement of upper versus lower limbs joints, a predominantly axial enthesitis versus peripheral enthesitis, and predominantly finger versus toe involvement in dactylitis. A poor agreement between the clusters and the rheumatologist's diagnosis as well as with the classification criteria was found. Conclusion These results suggest the presence of two main phenotypes (predominantly axial and predominantly peripheral) based on the presence and location of the peripheral manifestations.Pathophysiology and treatment of rheumatic disease

Is there a role for melatonin in fibromyalgia?

Fibromyalgia, characterised by persistent pain, fatigue, sleep disturbance and cognitive dysfunction, is a central sensitivity syndrome that also involves abnormality in peripheral generators and in the hypothalamic pituitary adrenal axis. Heterogeneity of clinical expression of fibromyalgia with a multifactorial aetiology has made the development of effective therapeutic strategies challenging. Physiological properties of the neurohormone melatonin appear related to the symptom profile exhibited by patients with fibromyalgia and thus disturbance of it’s production would be compatible with the pathophysiology. Altered levels of melatonin have been observed in patients with fibromyalgia which are associated with lower secretion during dark hours and higher secretion during daytime. However, inconsistencies of available clinical evidence limit conclusion of a relationship between levels of melatonin and symptom profiles in patients with fibromyalgia. Administration of melatonin to patients with fibromyalgia has demonstrated suppression of many symptoms and an improved quality of life consistent with benefit as a therapy for the management of this condition. Further studies with larger samples, however, are required to explore the potential role of melatonin in the pathophysiology of fibromyalgia and determine the optimal dosing regimen of melatonin for the management of fibromyalgia

Long-baseline neutrino oscillation physics potential of the DUNE experiment

The sensitivity of the Deep Underground Neutrino Experiment (DUNE) to neutrino oscillation is determined, based on a full simulation, reconstruction, and event selection of the far detector and a full simulation and parameterized analysis of the near detector. Detailed uncertainties due to the flux prediction, neutrino interaction model, and detector effects are included. DUNE will resolve the neutrino mass ordering to a precision of 5σ, for all ΑCP values, after 2 years of running with the nominal detector design and beam configuration. It has the potential to observe charge-parity violation in the neutrino sector to a precision of 3σ (5σ) after an exposure of 5 (10) years, for 50% of all ΑCP values. It will also make precise measurements of other parameters governing long-baseline neutrino oscillation, and after an exposure of 15 years will achieve a similar sensitivity to sin22θ13 to current reactor experiments

First results on ProtoDUNE-SP liquid argon time projection chamber performance from a beam test at the CERN Neutrino Platform

The ProtoDUNE-SP detector is a single-phase liquid argon time projection chamber with an active volume of 7.2× 6.1× 7.0 m3. It is installed at the CERN Neutrino Platform in a specially-constructed beam that delivers charged pions, kaons, protons, muons and electrons with momenta in the range 0.3 GeV/c to 7 GeV/c. Beam line instrumentation provides accurate momentum measurements and particle identification. The ProtoDUNE-SP detector is a prototype for the first far detector module of the Deep Underground Neutrino Experiment, and it incorporates full-size components as designed for that module. This paper describes the beam line, the time projection chamber, the photon detectors, the cosmic-ray tagger, the signal processing and particle reconstruction. It presents the first results on ProtoDUNE-SP\u27s performance, including noise and gain measurements, dE/dx calibration for muons, protons, pions and electrons, drift electron lifetime measurements, and photon detector noise, signal sensitivity and time resolution measurements. The measured values meet or exceed the specifications for the DUNE far detector, in several cases by large margins. ProtoDUNE-SP\u27s successful operation starting in 2018 and its production of large samples of high-quality data demonstrate the effectiveness of the single-phase far detector design

Prospects for beyond the Standard Model physics searches at the Deep Underground Neutrino Experiment

The Deep Underground Neutrino Experiment (DUNE) will be a powerful tool for a variety of physics topics. The high-intensity proton beams provide a large neutrino flux, sampled by a near detector system consisting of a combination of capable precision detectors, and by the massive far detector system located deep underground. This configuration sets up DUNE as a machine for discovery, as it enables opportunities not only to perform precision neutrino measurements that may uncover deviations from the present three-flavor mixing paradigm, but also to discover new particles and unveil new interactions and symmetries beyond those predicted in the Standard Model (SM). Of the many potential beyond the Standard Model (BSM) topics DUNE will probe, this paper presents a selection of studies quantifying DUNE’s sensitivities to sterile neutrino mixing, heavy neutral leptons, non-standard interactions, CPT symmetry violation, Lorentz invariance violation, neutrino trident production, dark matter from both beam induced and cosmogenic sources, baryon number violation, and other new physics topics that complement those at high-energy colliders and significantly extend the present reach

Long-baseline neutrino oscillation physics potential of the DUNE experiment

The sensitivity of the Deep Underground Neutrino Experiment (DUNE) to neutrino oscillation is determined, based on a full simulation, reconstruction, and event selection of the far detector and a full simulation and parameterized analysis of the near detector. Detailed uncertainties due to the flux prediction, neutrino interaction model, and detector effects are included. DUNE will resolve the neutrino mass ordering to a precision of 5σ, for all δ_(CP) values, after 2 years of running with the nominal detector design and beam configuration. It has the potential to observe charge-parity violation in the neutrino sector to a precision of 3σ (5σ) after an exposure of 5 (10) years, for 50% of all δ_(CP) values. It will also make precise measurements of other parameters governing long-baseline neutrino oscillation, and after an exposure of 15 years will achieve a similar sensitivity to sin²θ₁₃ to current reactor experiments