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1.
Scand J Rheumatol ; 52(2): 196-199, 2023 03.
Article in English | MEDLINE | ID: mdl-35833317

ABSTRACT

OBJECTIVE: To evaluate the relationship between reported coronavirus disease 2019 (COVID-19)-like symptoms and the presence of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) antibodies in patients with an immune-mediated inflammatory disorder or post-solid organ transplantation (IMIDT) with and without immunosuppressive medication (imed) and controls. METHOD: The IENIMINI cohort was a prospective cohort study set up in the Netherlands in March 2020, with 2 monthly (paper) or weekly (online) questionnaires about COVID-19-like symptoms. Participants from this cohort who reported these symptoms between March 2020 and November 2020 were approached for this substudy. SARS-CoV-2 antibodies were tested using a total antibody assay. RESULTS: Of the 1203 participants approached, 629 agreed to participate and were sent a fingerprick test; 565 participants collected a capillary blood sample, of which 562 were usable. Analysis showed that 57/202 (28.2%) of the tested IMIDT group with imed, 48/16 3(29.4%) of the IMIDT group without imed, and 69/197 (35.0%) of the control group tested positive for SARS-CoV-2 antibodies. Seroprevalences of SARS-CoV-2 antibodies between males and females, biological disease-modifying anti-rheumatic drug users and non-users, and those who had had a serious disease period (defined as an episode with dyspnoea and fever) and those who had not, were not statistically different between the three groups. CONCLUSIONS: Approximately 30% of patients who had reported COVID-19-like symptoms had SARS-CoV-2 antibodies. The seroprevalence of SARS-CoV-2 antibodies after reported COVID-19-like symptoms was similar in IMIDT patients with and without imed compared to controls.


Subject(s)
COVID-19 , Male , Female , Humans , COVID-19/epidemiology , SARS-CoV-2 , Prospective Studies , Seroepidemiologic Studies , Risk Factors , Antibodies, Viral
2.
Scand J Rheumatol ; 52(3): 243-249, 2023 05.
Article in English | MEDLINE | ID: mdl-35274588

ABSTRACT

OBJECTIVE: Several biomarkers of cardiovascular function are found to be increased in rheumatoid arthritis (RA), with some suggesting a relationship with disease activity and improvement with adequate anti-rheumatic treatment. Promising biomarkers include N-terminal pro-brain natriuretic peptide (NT-proBNP) and the soluble receptor form of advanced glycation end-products (sRAGE). The objective of this study was to investigate associations between NT-proBNP and sRAGE levels and markers of inflammation and disease activity in early RA patients and their changes during (effective) anti-rheumatic treatment. METHOD: Data from 342 consecutive early RA patients participating in the 'Parelsnoer' cohort were used. At baseline and after 6 months' disease activity, NT-proBNP and sRAGE levels were assessed. RESULTS: After 6 months, NT-proBNP decreased from 83 pmol/L (mean) at baseline to 69 pmol/L at follow-up (p < 0.001), while sRAGE increased from 997 pg/mL to 1125 pg/mL (p < 0.001). A larger decrease in erythrocyte sedimentation rate (ESR) or C-reactive protein (CRP) was associated with larger changes in NT-proBNP and sRAGE. For every point decrease in ESR, there was a 1.7-point decrease in NT-proBNP and a 2.2-point increase in sRAGE. For CRP, these values were 1.7 and 2.7, respectively (p < 0.001). CONCLUSION: Suppressing inflammation, independently of achieving remission, increases sRAGE levels and decreases NT-proBNP levels significantly. Whether this translates into a decrease in incident cardiovascular disease remains to be elucidated.


Subject(s)
Arthritis, Rheumatoid , Humans , Natriuretic Peptide, Brain , Inflammation , C-Reactive Protein/metabolism , Biomarkers
3.
Ultrasound Obstet Gynecol ; 59(5): 651-659, 2022 05.
Article in English | MEDLINE | ID: mdl-34558747

ABSTRACT

OBJECTIVES: Two-dimensional speckle-tracking echocardiography (2D-STE) is a promising technique which allows assessment of fetal cardiac function, and can be used in the evaluation of cardiac and non-cardiac diseases in pregnancy. However, reliable fetal reference values for deformation parameters measured using 2D-STE are needed before it can be introduced into clinical practice. This study aimed to obtain reference values for fetal global longitudinal strain (GLS) and GLS rate (GLSR) measured using 2D-STE and compare right and left ventricular values. METHODS: This was a prospective longitudinal cohort study of uncomplicated pregnancies that underwent echocardiography every 4 weeks from inclusion at 18-21 weeks until delivery to obtain four-chamber loops of the fetal heart. Left and right ventricular GLS and GLSR were measured using 2D-STE at each examination. Using Bayesian mixed-effects models, reference values with lower and upper 5% prediction limits were calculated according to gestational age. Right and left ventricular GLS values according to gestational age were compared using the Wilcoxon signed-rank test. RESULTS: A total of 592 left ventricular and 566 right ventricular GLS and GLSR measurements were obtained from 124 women with uncomplicated pregnancy and non-anomalous, appropriately grown fetuses. Reference values were obtained for both fetal ventricles according to gestational week. GLS and GLSR values of both ventricles increased (i.e. became less negative) significantly during pregnancy. Right ventricular GLS values were significantly higher (i.e. less negative) than the respective left ventricular values at every gestational week. CONCLUSIONS: Reference values were obtained for fetal GLS and GLSR measured using 2D-STE. GLS and GLSR values increased significantly for both ventricles from the second trimester until delivery. GLS values were significantly higher for the right ventricle compared with the left ventricle. Future studies are needed to assess whether the obtained reference values are helpful in clinical practice in the assessment of pregnancy complications, such as fetal growth restriction or cardiac anomaly. © 2022 The Authors. Ultrasound in Obstetrics & Gynecology published by John Wiley & Sons Ltd on behalf of International Society of Ultrasound in Obstetrics and Gynecology.


Subject(s)
Echocardiography , Ultrasonography, Prenatal , Bayes Theorem , Echocardiography/methods , Female , Fetal Heart/diagnostic imaging , Heart Ventricles/diagnostic imaging , Humans , Longitudinal Studies , Male , Pregnancy , Prospective Studies , Reproducibility of Results , Ventricular Function, Left
4.
BMC Pregnancy Childbirth ; 21(1): 791, 2021 Nov 25.
Article in English | MEDLINE | ID: mdl-34823483

ABSTRACT

BACKGROUND: Worldwide, hypertensive disorders of pregnancy (HDP), fetal growth restriction (FGR) and preterm birth remain the leading causes of maternal and fetal pregnancy-related mortality and (long-term) morbidity. Fetal cardiac deformation changes can be the first sign of placental dysfunction, which is associated with HDP, FGR and preterm birth. In addition, preterm birth is likely associated with changes in electrical activity across the uterine muscle. Therefore, fetal cardiac function and uterine activity can be used for the early detection of these complications in pregnancy. Fetal cardiac function and uterine activity can be assessed by two-dimensional speckle-tracking echocardiography (2D-STE), non-invasive fetal electrocardiography (NI-fECG), and electrohysterography (EHG). This study aims to generate reference values for 2D-STE, NI-fECG and EHG parameters during the second trimester of pregnancy and to investigate the diagnostic potential of these parameters in the early detection of HDP, FGR and preterm birth. METHODS: In this longitudinal prospective cohort study, eligible women will be recruited from a tertiary care hospital and a primary midwifery practice. In total, 594 initially healthy pregnant women with an uncomplicated singleton pregnancy will be included. Recordings of NI-fECG and EHG will be made weekly from 22 until 28 weeks of gestation and 2D-STE measurements will be performed 4-weekly at 16, 20, 24 and 28 weeks gestational age. Retrospectively, pregnancies complicated with pregnancy-related diseases will be excluded from the cohort. Reference values for 2D-STE, NI-fECG and EHG parameters will be assessed in uncomplicated pregnancies. After, 2D-STE, NI-fCG and EHG parameters measured during gestation in complicated pregnancies will be compared with these reference values. DISCUSSION: This will be the a large prospective study investigating new technologies that could potentially have a high impact on antepartum fetal monitoring. TRIAL REGISTRATION: Registered on 26 March 2020 in the Dutch Trial Register (NL8769) via https://www.trialregister.nl/trials and registered on 21 October 2020 to the Central Committee on Research Involving Human Subjects (NL73607.015.20) via https://www.toetsingonline.nl/to/ccmo_search.nsf/Searchform?OpenForm .


Subject(s)
Echocardiography/methods , Electrocardiography/methods , Prenatal Diagnosis/methods , Adult , Female , Fetal Growth Retardation/diagnosis , Heart Rate, Fetal/physiology , Humans , Hypertension, Pregnancy-Induced/diagnosis , Longitudinal Studies , Netherlands , Pregnancy , Pregnancy Trimester, Second , Premature Birth/diagnosis , Prospective Studies , Uterine Monitoring , Uterus/physiology
5.
Ultrasound Obstet Gynecol ; 61(2): 275-277, 2023 02.
Article in English | MEDLINE | ID: mdl-36722426
6.
Ann Rheum Dis ; 76(4): 716-720, 2017 04.
Article in English | MEDLINE | ID: mdl-28283528

ABSTRACT

OBJECTIVES: In rheumatoid arthritis (RA), seropositive and seronegative disease may be two entities with different underlying pathophysiological mechanisms, long-term outcomes and disease presentations. However, the effect of the conjoint presence of multiple autoantibodies, as proxy for a more pronounced humoral autoimmune response, on clinical phenotype remains unclear. Therefore, this study investigates the association between the number of autoantibodies and initial clinical presentation in two independent cohorts of patients with early RA. METHODS: Autoantibody status (rheumatoid factor, anticitrullinated protein antibodies and anticarbamylated protein antibodies) was determined at baseline in the Leiden Early Arthritis Cohort (n=828) and the Swedish BARFOT (Better Anti-Rheumatic Farmaco-Therapy, n=802) study. The association between the number of autoantibodies and baseline clinical characteristics was investigated using univariable and multivariable ordinal regression. RESULTS: In both cohorts, the following independent associations were found in multivariable analysis: patients with a higher number of RA-associated antibodies were younger, more often smokers, had a longer symptom duration and a higher erythrocyte sedimentation rate at presentation compared with patients with few autoantibodies. CONCLUSIONS: The number of autoantibodies, reflecting the breadth of the humoral autoimmune response, is associated with the clinical presentation of RA. Predisease pathophysiology is thus reflected by the initial clinical phenotype.


Subject(s)
Arthritis, Rheumatoid/blood , Autoantibodies/blood , Peptides, Cyclic/immunology , Rheumatoid Factor/immunology , Adult , Age Factors , Aged , Alleles , Arthritis, Rheumatoid/genetics , Arthritis, Rheumatoid/immunology , Blood Sedimentation , Female , Humans , Immunity, Humoral , Male , Middle Aged , Phenotype , Smoking
7.
Eur J Obstet Gynecol Reprod Biol ; 291: 123-127, 2023 Dec.
Article in English | MEDLINE | ID: mdl-37866275

ABSTRACT

OBJECTIVE(S): Accidental rupture of membranes (acROM), an insertion-related complication of the balloon catheter for labor induction, may prolong the duration of ruptured membranes. Prolonged rupture of membranes is associated with an increased risk of intra-uterine infection with possibly neonatal infection as result. Little is known about safety profiles of different catheters regarding the occurrence of these complications. This study compares the incidence of neonatal early-onset sepsis (EOS) and acROM in women receiving either silicone or latex balloon catheters. STUDY DESIGN: A retrospective cohort study was performed including 2200 women (silicone balloon catheter, n = 1100 vs. latex balloon catheter, n = 1100). The primary outcomes were the incidence of acROM, and suspected and proven neonatal EOS. Secondary outcomes were: prolonged rupture of membranes, intrapartum fever, pre- or postnatal neonatal exposure to antibiotics, and perinatal outcomes. A subgroup analysis was performed between women with and without acROM. RESULTS: No statistically significant difference with regard to suspected or proven EOS was seen between the silicone and latex groups. The acROM rate was significantly higher in the silicone group compared to the latex group (2.9 % and 0.3 %, p < 0.01). Prolonged rupture of membranes was significantly more common in the silicone group compared to the latex group (5.0 % and 2.4 %, p < 0.01), as was the use of intrapartum antibiotics (12.7 % and 9.6 %, p = 0.02). Neonates were significantly more often exposed to pre- or postnatal antibiotics in the silicone group compared to the latex group (17.6 % and 13.6 %, p = 0.01). Subgroup analysis showed significantly more suspected and proven neonatal EOS when catheter-insertion was complicated with acROM (11.4 % and 20.0 %), compared to cases without acROM (3.8 % and 2.5 %), irrespective of the type of catheter used. CONCLUSION(S): The use of silicone balloon catheters for labor induction results in higher rates of acROM, prolonged rupture of membranes and use of intrapartum antibiotics, compared to latex balloon catheters. No statistically significant differences were found in the occurrence of suspected or proven neonatal EOS, however neonates from the silicone group were more often exposed to pre- or postnatal antibiotics. When acROM occurs, irrespective of type of catheter used, suspected and proven neonatal EOS was seen more often.


Subject(s)
Fetal Membranes, Premature Rupture , Neonatal Sepsis , Infant, Newborn , Pregnancy , Female , Humans , Latex/adverse effects , Retrospective Studies , Silicones/adverse effects , Labor, Induced/methods , Urinary Catheters , Catheters/adverse effects , Fetal Membranes, Premature Rupture/epidemiology , Fetal Membranes, Premature Rupture/etiology , Anti-Bacterial Agents/therapeutic use , Cervical Ripening
8.
Article in English | MEDLINE | ID: mdl-35131629

ABSTRACT

OBJECTIVE: Current guidelines provide little supporting literature for the definition of uterine tachysystole during labour and no distinction is made for optimal contraction frequency depending on the clinical situation. We hypothesize that fetal hypoxia is frequently caused by uterine tachysystole and that high uterine contraction frequencies are especially harmful when fetal heart rate (FHR) abnormalities are present. We studied the association between contraction frequency and fetal scalp pH values in women with an indication for fetal blood sampling (FBS) based on FHR abnormalities. STUDY DESIGN: A retrospective study including 762 women was performed in a tertiary teaching hospital in the Netherlands from January 2015 until January 2020. Women with a singleton pregnancy with a gestational age ≥ 34+0 weeks were included when FBS was performed because of suspicious or pathological FHR tracings. Exclusion criteria were maternal age < 18 years, failed fetal scalp pH values, lack of thirty minute registration by tocodynamometry prior to FBS, poor quality of uterine monitoring, intrauterine resuscitation in the thirty minutes prior to FBS, maternal body mass index ≥ 30 kg/m2 and neonatal birth weight < 10th percentile. Uterine contractions in the thirty minutes prior to FBS were manually annotated by a researcher who was blinded to FBS values, FHR and other obstetrical data. Linear and logistic analysis were used to explore the association between uterine contraction frequency and FBS results. RESULTS: Low fetal scalp pH values were significantly associated with contraction frequency prior to FBS. Fetuses of women with four to five contractions per ten minutes prior to FBS were 2.4 times more likely to have hypoxia as compared to fetuses of women with two to three contractions per ten minutes (aOR 2.4, 95% CI 1.1-5.4). With increasing contraction frequency, the risk of fetal hypoxia further increased. CONCLUSIONS: Contraction frequency above four per ten minutes prior to FBS is significantly associated with fetal hypoxia in women with FHR abnormalities. We suggest to aim for a maximum contraction frequency of four per ten minutes in these women.


Subject(s)
Heart Rate, Fetal , Uterine Contraction , Adolescent , Female , Fetus , Heart Rate, Fetal/physiology , Humans , Hydrogen-Ion Concentration , Infant , Infant, Newborn , Pregnancy , Retrospective Studies , Scalp
10.
Ann Rheum Dis ; 70(2): 373-9, 2011 Feb.
Article in English | MEDLINE | ID: mdl-21068094

ABSTRACT

OBJECTIVES: Anti-citrullinated protein antibodies (ACPA) are highly specific for rheumatoid arthritis (RA) and have been implicated in disease pathogenesis. Recent ongoing evidence indicates that the ACPA response broadens before precipitation of full-blown RA, as indicated by a more extensive isotype usage and an increased citrullinated epitope recognition profile. Nonetheless, the evolution of the ACPA response is still poorly understood and might intrinsically differ from the protective responses against pathogens. METHODS: The avidity and the avidity maturation of ACPA in relation to the avidity of antibodies against recall antigens were analysed. RESULTS: The avidity of ACPA was significantly lower than the avidity of antibodies to the recall antigens tetanus toxoid and diptheria toxoid. Moreover, ACPA did not show avidity maturation during longitudinal follow-up and ACPA avidity was also relatively low in patients who displayed extensive isotype switching. CONCLUSIONS: These observations indicate that the natural evolution of ACPA differs from the development of antibodies against recall antigens. These data also indicate that ACPA avidity maturation and isotype switching are disconnected, whereby extensive isotype switching occurs in the setting of restricted avidity maturation. Intrinsic differences between the RA-specific autoantibody system and protective antibody responses against pathogens could be of relevance for designing novel B cell-targeted therapies for RA.


Subject(s)
Arthritis, Rheumatoid/immunology , Autoantibodies/immunology , Peptides, Cyclic/immunology , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Bacterial/immunology , Antibody Affinity , Diphtheria Toxoid/immunology , Female , Humans , Immunoglobulin G/immunology , Immunologic Memory , Male , Middle Aged , Tetanus Toxoid/immunology , Young Adult
11.
Arthritis Res Ther ; 23(1): 298, 2021 12 08.
Article in English | MEDLINE | ID: mdl-34876234

ABSTRACT

BACKGROUND: Besides anti-citrullinated protein antibodies (ACPA), rheumatoid arthritis patients (RA) often display autoantibody reactivities against other post-translationally modified (PTM) proteins, more specifically carbamylated and acetylated proteins. Immunizing mice with one particular PTM results in an anti-modified protein antibody (AMPA) response recognizing different PTM-antigens. Furthermore, human AMPA, isolated based on their reactivity to one PTM, cross-react with other PTMs. However, it is unclear whether the AMPA-reactivity profile is "fixed" in time or whether consecutive exposure to different PTMs can shape the evolving AMPA response towards a particular PTM. METHODS: Longitudinally collected serum samples of 8 human individuals at risk of RA and 5 with early RA were tested with ELISA, and titers were analyzed to investigate the evolution of the AMPA responses over time. Mice (13 per immunization group in total) were immunized with acetylated (or carbamylated) protein (ovalbumin) twice or cross-immunized with an acetylated and then a carbamylated protein (or vice versa) and their serum was analyzed for AMPA responses. RESULTS: Human data illustrated dynamic changes in AMPA-reactivity profiles in both individuals at risk of RA and in early RA patients. Mice immunized with either solely acetylated or carbamylated ovalbumin (AcOVA or CaOVA) developed reactivity against both acetylated and carbamylated antigens. Irrespective of the PTM-antigen used for the first immunization, a booster immunization with an antigen bearing the other PTM resulted in increased titers to the second/booster PTM. Furthermore, cross-immunization skewed the overall AMPA-response profile towards a relatively higher reactivity against the "booster" PTM. CONCLUSIONS: The relationship between different reactivities within the AMPA response is dynamic. The initial exposure to a PTM-antigen induces cross-reactive responses that can be boosted by an antigen bearing this or other PTMs, indicating the formation of cross-reactive immunological memory. Upon subsequent exposure to an antigen bearing another type of PTM, the overall reactivity pattern can be skewed towards better recognition of the later encountered PTM. These data might explain temporal differences in the AMPA-response profile and point to the possibility that the PTM responsible for the initiation of the AMPA response may differ from the PTM predominantly recognized later in time.


Subject(s)
Antibody Formation , Autoantigens , Animals , Anti-Citrullinated Protein Antibodies , Autoantibodies , Autoantigens/metabolism , Humans , Mice , Protein Processing, Post-Translational
12.
Best Pract Res Clin Rheumatol ; 22(2): 299-310, 2008 Apr.
Article in English | MEDLINE | ID: mdl-18455686

ABSTRACT

Findings from basic research in combination with precise clinical observations of the disease course in rheumatoid arthritis (RA) have led to the development of a multistage model to explain the pathophysiology of RA. Different cellular and soluble mediators, which play principal roles at different phases of the disease, have been identified. New therapeutic agents, which specifically target these factors, now allow us to intervene at several levels of the pathogenesis. This has already resulted in significant improvements for patients suffering from RA, and the development of new promising agents continues at a high pace. However, many questions concerning the optimal use of the new therapies remain unanswered. Combined efforts of basic research and clinical trials investigating the optimal timing and combination of the new treatments will be necessary to allow them to achieve their full potential and to result in the maximum benefit for patients.


Subject(s)
Antirheumatic Agents/pharmacology , Arthritis, Rheumatoid/drug therapy , Arthritis, Rheumatoid/physiopathology , Immunologic Factors/pharmacology , Autoantibodies/drug effects , B-Lymphocytes/drug effects , Cytokines/drug effects , Humans , Immunity, Innate/drug effects , T-Lymphocytes/drug effects
13.
Int J Lab Hematol ; 40(1): 72-76, 2018 Feb.
Article in English | MEDLINE | ID: mdl-28868811

ABSTRACT

INTRODUCTION: Total vitamin B12 levels decrease significantly during pregnancy and recover to normal values within 8-week postpartum. Holotranscobalamin (holoTC) reflects the active part of vitamin B12 and has been shown to remain constant during pregnancy and postpartum. A mechanism of redistribution of vitamin B12 is suggested, with a shift toward holoTC if there is insufficient total vitamin B12 available. Our objective was to examine vitamin B12 deficiency and the active vitamin B12 fraction in postpartum women. METHODS: Total vitamin B12 and holoTC were measured in 171 women within 48 hours (T0) and at 5 weeks (T5) postpartum. Vitamin B12 deficiency was defined as total vitamin B12 < 180 pmol/L or holoTC <32 pmol/L. The active vitamin B12 fraction was defined as holoTC/total vitamin B12. RESULTS: Without intervention, vitamin B12 deficiency based on both serum total vitamin B12 and holoTC changed from 75% and 60%, to respectively 10% and 6% at T5. The fraction of active vitamin B12 was significant higher in vitamin B12 deficient women at both time points and across time (P < .0001 and P = .002). A high fraction of active vitamin B12 was only present in women with total vitamin B12 deficiency at T0. At T5, no high vitamin B12 fraction was found. CONCLUSION: The changes in total vitamin B12 levels seem to be based on a physiological changes rather than vitamin B12 deficiency. The results of this study confirm the hypothesis that a shift toward the metabolic active vitamin B12 (holoTC) occurs in women with insufficient available total vitamin B12.


Subject(s)
Postpartum Period/blood , Vitamin B 12/blood , Adult , Female , Humans , Pregnancy , Time Factors , Vitamin B 12 Deficiency/blood
14.
Semin Immunopathol ; 39(4): 437-446, 2017 06.
Article in English | MEDLINE | ID: mdl-28451788

ABSTRACT

Rheumatoid arthritis (RA) is an autoimmune disease characterized by joint inflammation. The presence of autoantibodies in the sera of RA patients has provided many clues to the underlying disease pathophysiology. Based on the presence of several autoantibodies like rheumatoid factor (RF), anti-citrullinated protein antibodies (ACPA), anti-carbamylated protein antibodies (anti-CarP), and more recently anti-acetylated protein antibodies RA can be subdivided into seropositive and seronegative disease. The formation of these autoantibodies is associated with both genetic and environmental risk factors for RA, like specific human leukocyte antigen (HLA) alleles and smoking. Autoantibodies can be detected many years before disease onset in a subset of patients, suggesting a sequence of events in which the first autoantibodies develop in predisposed hosts, before an inflammatory response ensues leading to clinically apparent arthritis. Research on the characteristics and effector functions of these autoantibodies might provide more insight in pathophysiological processes underlying arthritis in RA. Recent data suggests that ACPA might play a role in perpetuating inflammation once it has developed. Furthermore, pathophysiological mechanisms have been discovered supporting a direct link between the presence of ACPA and both bone erosions and pain in RA patients. In conclusion, investigating the possible pathogenic potential of autoantibodies might lead to improved understanding of the underlying pathophysiological processes in rheumatoid arthritis.


Subject(s)
Arthritis, Rheumatoid/etiology , Autoantibodies/immunology , Autoimmunity , Animals , Arthritis, Rheumatoid/metabolism , Arthritis, Rheumatoid/pathology , Autoantigens/immunology , Environment , Gene-Environment Interaction , Genetic Predisposition to Disease , Humans , Microbiota/immunology , Risk Factors , Signal Transduction
17.
Best Pract Res Clin Rheumatol ; 28(4): 551-64, 2014 Aug.
Article in English | MEDLINE | ID: mdl-25481549

ABSTRACT

Undifferentiated arthritis (UA) is a frequently occurring clinical presentation with a variable outcome. While some forms of UA will spontaneously remit, other forms will progress to chronic arthritis; an outcome that would preferably be prevented. Which immunological factors are normally at the basis of resolution of inflammation, and what, on the other hand, causes inflammation to persist? This review provides an overview of the immunological mechanisms involved in these two scenarios, including specific examples of how these mechanisms apply, or can be influenced in rheumatic diseases. Furthermore, what do we know about risk factors for chronic arthritis, such as the development of autoantibodies? The recent years have provided many insights concerning risk factors for autoantibody-positive versus autoantibody-negative rheumatoid arthritis, which are discussed along with a possible pathophysiological model incorporating autoantibodies into the larger process of disease development. Finally, the evolution of the autoantibody response over time is described.


Subject(s)
Arthritis, Rheumatoid/immunology , Arthritis/immunology , Inflammation/immunology , Autoantibodies/immunology , Chronic Disease , Disease Progression , Humans , Risk Factors
19.
Int J Lab Hematol ; 34(5): 510-6, 2012 Oct.
Article in English | MEDLINE | ID: mdl-22548729

ABSTRACT

INTRODUCTION: To evaluate the use of reticulocyte hemoglobin content (CHr) and mean corpuscular volume (MCV) to identify truly iron-deficient women with postpartum anemia (PPA), in order to reduce unnecessary iron supplementation. METHODS: Three hundred women with more than 500 mL of blood loss or clinical signs of anemia were divided in a control (Hb ≥ 10.5 g/dL, N = 150) and postpartum anemia group (PPA, Hb < 10.5 g/dL; N = 150). PPA women were given ferrous fumarate for a period of 4 weeks. Efficacy of the treatment was evaluated by comparing Hb, CHr, and MCV at baseline (T(0)) and after 4 weeks (T(4)). Using standard iron deficiency cut off values for MCV (80 fL) and CHr (28 pg) at T(0), we divided the PPA group of both parameters into two subgroups, one suggestive for iron deficiency and one suggestive for noniron deficiency. RESULTS: Irrespective of the parameter or the subdivision, delta Hb concentrations (T(4) -T(0)) showed a similar increase in all PPA subgroups investigated. Both parameters in the PPA subgroups below their respective cut off value showed a significant improvement toward normalization, while the MCV and CHr in the PPA subgroups above their respective cut off value did not show any significant increase. CONCLUSION: Our data suggest that the etiology of the anemia in postpartum anemic women is not always iron deficiency. Using a combination of Hb, MCV and CHr, we increased the stringency to identify truly iron-deficient postpartum anemic women, thereby reducing unnecessary iron supplementation in those women with sufficient iron stores.


Subject(s)
Anemia, Iron-Deficiency/blood , Anemia/blood , Erythrocyte Indices , Hemoglobins/metabolism , Reticulocytes/metabolism , Adult , Anemia/complications , Anemia/drug therapy , Anemia, Iron-Deficiency/diagnosis , Anemia, Iron-Deficiency/etiology , Female , Ferrous Compounds/therapeutic use , Humans , Postpartum Period , Predictive Value of Tests , Reticulocytes/cytology , Time Factors , Trace Elements/therapeutic use , Young Adult
20.
Arthritis Rheum ; 60(7): 1923-31, 2009 Jul.
Article in English | MEDLINE | ID: mdl-19565507

ABSTRACT

OBJECTIVE: It has been suggested that anti-citrullinated protein antibodies (ACPAs) play an important role in the pathogenesis of rheumatoid arthritis (RA). To exert their pathologic effects, ACPAs must recruit immune effector mechanisms such as activation of the complement system. Mouse models of RA have shown that, surprisingly, arthritogenic antibodies activate the alternative pathway of complement rather than the expected classical pathway. This study was undertaken to investigate whether human anti-cyclic citrullinated peptide (anti-CCP) antibodies activate the complement system in vitro and, if so, which pathways of complement activation are used. METHODS: We set up novel assays to analyze complement activation by anti-CCP antibodies, using cyclic citrullinated peptide-coated plates, specific buffers, and normal and complement-deficient sera as a source of complement. RESULTS: Anti-CCP antibodies activated complement in a dose-dependent manner via the classical pathway of complement, and, surprisingly, via the alternative pathway of complement. The lectin pathway was not activated by anti-CCP antibodies. Complement activation proceeded in vitro up to the formation of the membrane attack complex, indicating that all activation steps, including the release of C5a, took place. CONCLUSION: Our findings indicate that anti-CCP antibodies activate the complement system in vitro via the classical and alternative pathways but not via the lectin pathway. These findings are relevant for the design of interventions aimed at inhibition of complement-mediated damage in RA.


Subject(s)
Antibodies, Anti-Idiotypic/metabolism , Arthritis, Rheumatoid/metabolism , Complement System Proteins/metabolism , Peptides, Cyclic/immunology , Signal Transduction/physiology , Adolescent , Adult , Aged , Aged, 80 and over , Arthritis, Rheumatoid/immunology , Case-Control Studies , Cohort Studies , Complement C1q/metabolism , Complement C5a/metabolism , Complement Membrane Attack Complex/metabolism , Female , Humans , Lectins/metabolism , Male , Mannose-Binding Lectin/metabolism , Middle Aged , Young Adult
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