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J W Tervaert

Publications and source records attributed to J W Tervaert.

At least 55 records · Page 3Linked to original sources
PubMed1998

Levels of soluble Fc gammaRIII correlate with disease severity in sepsis.

Neutrophil activation is thought to play a crucial role in the pathogenesis of sepsis. During activation, neutrophils adhere to and migrate through the endothelium. Therefore, the amount of circulating neutrophils does not adequately reflect the total amount of neutrophils that are involved in the pathophysiologic process of this condition. In this study we test the hypothesis that the severity of sepsis is associated with the total body mass of neutrophils as reflected in the plasma concentration of soluble Fc gamma receptor type III (sFc gammaRIII). Nineteen patients with sepsis (12 male, seven female, median age of 69 years, range 29-87 years) were included in this study. Ten healthy volunteers served as controls. Plasma sFc gammaRIII concentrations were measured by ELISA. Other parameters that were studied were leucocyte count, plasma concentrations of lactoferrin and soluble L-selectin, and surface expression of CD11b and CD66b on circulating neutrophils. Disease activity was measured using the Acute Physiology and Chronic Health Evaluation (APACHE) II score. Soluble Fc gammaRIII levels were elevated in sepsis patients whereas soluble L-selectin levels were moderately decreased compared with healthy controls. Markers of cell activation were significantly increased in sepsis patients. Soluble Fc gammaRIII correlated with disease severity as measured by the APACHE score (P<0.05, r=0.53), whereas the other parameters did not correlate with the APACHE score. In conclusion, this study demonstrates that soluble Fc gammaRIII is a useful marker for disease severity in patients with sepsis.

Adult↗
PubMed1998

Are circulating neutrophils intravascularly activated in patients with anti-neutrophil cytoplasmic antibody (ANCA)-associated vasculitides?

Vascular injury in vasculitis may be due to activation of circulating neutrophils resulting in their increased adhesiveness to locally activated endothelium (Shwartzman phenomenon). Previously, we demonstrated up-regulation of endothelial intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) in biopsies from patients with ANCA-associated vasculitis. In the present study, we investigated the expression of adhesion molecules (CD11b, ICAM-1, VLA-4, L-selectin) and activation markers (CD66b, CD64, CD63) on circulating neutrophils from patients with ANCA-associated vasculitis in comparison with their expression on cells from healthy volunteers and patients with sepsis. We related these findings to parameters of disease activity. Surface marker expression was determined by using a non-activating whole blood flow cytometric assay. The expression of activation markers, but not the expression of adhesion molecules, was increased on neutrophils from patients with active vasculitis. The expression of CD63 and CD66b on neutrophils correlated with disease activity as determined by the Birmingham Vasculitis Activity Score (BVAS). In contrast to patients with active vasculitis, patients with sepsis showed up-regulation of all markers, including adhesion molecules, suggesting that circulating neutrophils are fully activated in sepsis. We conclude that in ANCA-associated vasculitis, circulating neutrophils are not fully activated, since they do not express increased levels of adhesion molecules as sepsis or in the Shwartzman reaction. These findings are compatible with the concept that in vivo vascular damage in ANCA-associated vasculitides does not occur due to a Shwarzman-like reaction but only after ANCA-induced neutrophil activation at the endothelial cell surface.

Adult↗
PubMed1998

Leucocyte membrane expression of proteinase 3 correlates with disease activity in patients with Wegener's granulomatosis.

Wegener's granulomatosis (WG) is an inflammatory disorder characterized by granulomatous inflammation and vasculitis, and is strongly associated with antineutrophil cytoplasmic antibodies (ANCA). ANCA in patients with WG are directed against proteinase 3 (Pr3) in most of the cases. In vitro, upon neutrophil priming, ANCA antigens are expressed on the cell surface, thereby becoming available for interaction with ANCA. Subsequently, these neutrophils become activated. Since ANCA can only interact with leucocytes when the ANCA antigens are present on the cell surface, we questioned whether Pr3 is already expressed on the membranes of circulating granulocytes and monocytes of patients with WG, and whether Pr3 expression is related to disease activity, so explaining the systemic nature and severity of the disease. The expression of Pr3, and other ANCA antigens, i.e. myeloperoxidase (MPO) and human leucocyte elastase (HLE), was analysed on circulating granulocytes and monocytes by flow cytometry, using a non-activating whole-blood method. Disease activity was quantitated using the Birmingham Vasculitis Activity Score (BVAS). Seventeen patients with active WG and anti-Pr3 antibodies were included in this study. Nine of these patients were also analysed at the time of remission. Twelve patients with sepsis served as positive controls, and 10 healthy volunteers as negative controls for granulocyte/monocyte activation. Pr3 expression on neutrophils was increased in patients with active WG compared to patients with quiescent disease and healthy controls. On monocytes, no differences in Pr3 expression were found between those groups. Furthermore, the expression of MPO and HLE did not differ between patient groups and healthy controls. Upon follow-up, the expression of Pr3 on neutrophils from patients with active WG decreased when patients went into remission. Pr3 expression on neutrophils correlated with the BVAS score (r = 0.40, P < 0.05). In conclusion, circulating neutrophils from patients with active WG have increased expression of Pr3. In addition, the expression of Pr3 correlates with disease activity, suggesting that the availability of Pr3 for interaction with ANCA plays a central role in the disease process.

Adult↗
PubMed1998

Silicon exposure and vasculitis.

A combination of risk factors are involved in susceptibility to a primary or secondary form of vasculitis. Most forms of vasculitis are probably genetically based but environmentally triggered. This review discusses currently available evidence for a pathophysiologic role of one possible environmental trigger, silica. Since 1960, several patients with pulmonary silicosis have been described that developed pauci-immune necrotizing crescentic glomerulonephritis, i.e., with either completely negative immunofluorescence findings or nonspecific granular IgM or C3 deposits along the capillary wall. Recently it was reported that these patients have antineutrophil cytoplasmic antibodies (ANCAs) that are in most cases directed to myeloperoxidase. Further, patients with pulmonary silicosis may develop microscopic polyangiitis, the syndrome of lung hemorrhage and nephritis, or Wegener's granulomatosis. To further substantiate the relation between silicon exposure and renal failure or vasculitis, several case-control studies have been reported. Exposure to silicon-containing compounds was found to be related to chronic renal failure (odds ratio, 1.7:2.5) or vasculitis (odds ratio, 6.5:14.0). The mechanisms by which silica may induce ANCA-associated glomerulonephritis or vasculitis are not well known. Silicon-containing compounds have a pronounced adjuvant effect on immune responses, and silica particles are potent stimulators of lymphocytes and monocytes or macrophages. Further, silica may induce apoptosis of monocytes or macrophages and possibly neutrophils. In conclusion, at present there is ample evidence that occupational exposure to silicon-containing compounds is related to the development of ANCA-associated glomerulonephritis and vasculitis, and silica is one of the first well-documented environmental triggers in these diseases.

Adult↗
PubMed1998

Determinants of renal outcome in anti-myeloperoxidase-associated necrotizing crescentic glomerulonephritis.

Patients with anti-myeloperoxidase (MPO)-associated necrotizing crescentic glomerulonephritis (NCGN) may develop chronic renal failure (CRF) leading to end-stage renal disease despite an initially favorable response to treatment. The aim of this study was to determine the prognostic value of clinical, laboratory, and histopathologic features at the time of presentation and during follow-up for the development of CRF in 21 consecutive anti-MPO-positive patients with NCGN. Renal function did not recover in two of five patients who were dialysis-dependent at presentation. The remaining 19 patients all went into remission and were off dialysis at 3 mo after diagnosis. At long-term follow-up, nine of these patients had stable renal function and did not relapse (group A), five patients developed CRF without signs of relapse (group B), and five patients relapsed (group C). At diagnosis, serum creatinine, C-reactive protein, and anti-MPO levels did not differ between groups A, B, and C. Microscopic erythrocyturia resolved in all patients within 4 mo of treatment. BP at presentation and during follow-up did not differ between groups A, B, and C. Proteinuria at diagnosis and in the first 6 mo after diagnosis was higher in patients who developed CRF than in patients with a stable renal function. Anti-MPO levels at 3 mo had decreased compared with anti-MPO levels at diagnosis in groups A and C, whereas anti-MPO levels did not fall significantly in patients who developed CRF. The predictive value of a renal biopsy at diagnosis on long-term renal outcome was limited. In conclusion, a higher degree of proteinuria at diagnosis and during follow-up as well as persistently elevated anti-MPO levels after induction of remission are associated with the development of CRF and are predictive of poor renal outcome in anti-MPO-associated NCGN.

Adrenal Cortex Hormones↗
PubMed1997

Specificity, pathogenecity, and clinical value of antiendothelial cell antibodies.

OBJECTIVE: To characterize the putative target antigens for antiendothelial cell antibodies (AECA), the possible pathophysiological role of AECA, and the clinical value of these antibodies as markers of disease activity. METHODS: A structured literature search was done using Medline in combination with a manual search. Two physicians reviewed all articles of special interest. RESULTS: AECA are a heterogenous group of antibodies directed against a variety of antigen determinants on endothelial cells (EC). The EC antigens can be constitutively expressed, constitutively expressed and modulated by cytokines, or cryptic. In addition, antigen determinants for AECA may also be molecules that adhere to EC ("planted" antigens). However, many AECA antigens are currently not well characterized. AECA are detected in a wide variety of inflammatory disorders. Although probably of limited value in disease diagnosis, the detection of these antibodies may be valuable in following disease activity. In several diseases such as systemic lupus erythematosus and systemic vasculitis, high AECA titers are found during active disease whereas lower titers or disappearence of AECA have been reported during remission. The correlation between changes in AECA titers and disease activity suggests an important role for AECA in processes in which vessel wall damage occurs, although it does not exclude the possibility that AECA are an epiphenomenon of vascular injury. Several recent in vitro studies support a role of AECA in the pathophysiology of these inflammatory disorders. AECA may play a role in the pathophysiology by inducing activation of EC resulting in upregulation in the expression of endothelial adhesion molecules and/or secretion of chemoattractants and cytokines. An alternative mechanism by which AECA could be a trigger in the pathogenesis of some diseases is complement dependent cytotoxicity (CDC) and/or antibody dependent cellular cytotoxicity (ADCC). In experimental animal models, antibodies to antigenic determinants expressed on EC were capable of inducing vascular injury. CONCLUSION: AECA represent a heterogenous group of antibodies directed against a variety of antigenic determinants on EC. They are present in a variety of inflammatory disorders. The detection of these antibodies may be valuable in following disease activity. Further characterization of putative antigens is needed to better understand their pathophysiological role.

Animals↗
PubMed1997

Cell adhesion molecules in vasculitis.

Activation of the vascular endothelium by several different stimuli plays a crucial role in the initiation, localization, and propagation of vascular injury. In vitro studies have demonstrated that activation of cultured vascular endothelial cells renders them hyperadhesive for leukocytes. During the past decade it has become evident which cell adhesion molecules play a critical role in the interaction between the vascular endothelium and leukocytes in inflammation in general. Over the past year, advances have been made in understanding the interactions between leukocytes and vascular endothelial cells in vasculitis. Several studies have shown increased expression of adhesion molecules on circulating leukocytes and, in situ, in vasculitic lesions. Soluble adhesion molecules have appeared to be general nonspecific markers of endothelial activation. Hence, the clinical relevance of measuring soluble adhesion molecules is limited. Finally, the possibility of inhibiting adhesion molecule function in vivo remains an attractive therapeutic option in the vasculitides and is a focus of increasing research activity.

Biomarkers↗
PubMed1997

Systemic injection of products of activated neutrophils and H2O2 in myeloperoxidase-immunized rats leads to necrotizing vasculitis in the lungs and gut.

The strong association of anti-neutrophil cytoplasmic antibodies with various forms of systemic vasculitis suggests a role for these autoantibodies in the pathophysiology of systemic vasculitis. In the present study, we tested the hypothesis that release of neutrophil lysosomal enzymes in the presence of an anti-myeloperoxidase (anti-MPO) immune response may underlie the development of systemic vasculitis. Brown Norway rats were immunized with MPO in complete Freund's adjuvant or complete Freund's adjuvant alone. Two weeks after immunization, rats bad developed antibodies to human and rat MPO as measured by enzyme-linked immunosorbent assay. Next, rats were intravenously infused with 400 micrograms of a human neutrophil lysosomal extract containing 200 micrograms of MPO followed by 0.5 ml of a 1 mmol/L solution of H2O2 through a cannula inserted into the right jugular vein. Rats were sacrificed at 4 hours, 24 hours, 7 days, or 14 days, and several organs (lungs, heart, liver, spleen, gut, and kidneys) were examined for vasculitic lesions and inflammatory cell infiltrates. Macroscopically, patchy hemorrhagic spots were observed in the lungs and gut of MPO-immunized rats at days 7 and 14 after systemic infection of the neutrophil lysosomal extract and H2O2. Such changes were not observed at earlier time points or in control immunized rats. Histologically, the lungs of MPO-immunized rats sacrificed at days 7 and 14 showed patchy inflammatory cell infiltrates associated with vasculitis, granuloma formation, giant cells, and foci of hemorrhage. At 14 days, early signs of fibrosis were found with deposition of collagen and proliferation of fibroblasts. Furthermore, a prominent leukocytoclastic vasculitis was found in the small intestine of these rats characterized by fibrinoid necrosis and an extensive neutrophilic infiltrate. No inflammatory changes were found in the other organs studied (heart, liver, spleen, and kidneys). Control immunized rats, sacrificed at days 7 and 14 showed only some small foci of inflammatory infiltrates in the lungs whereas no inflammatory changes were found in the gastrointestinal tract. These studies show that release of products from activated neutrophils in the presence of anti-MPO autoantibodies may be relevant to the pathogenesis of anti-MPO-associated vasculitides.

Animals↗
PubMed1996

Trimethoprim-sulfamethoxazole (co-trimoxazole) for the prevention of relapses of Wegener's granulomatosis. Dutch Co-Trimoxazole Wegener Study Group.

BACKGROUND: Respiratory tract infections may trigger relapses in patients with Wegener's granulomatosis in remission. Uncontrolled data have suggested that treatment with trimethoprim-sulfamethoxazole (co-trimoxazole) may be beneficial. METHODS: We conducted a prospective, randomized, placebo-controlled study of the efficacy of co-trimoxazole (800 mg of sulfamethoxazole and 160 mg of trimethoprim) given twice daily for 24 months in preventing relapses in patients with Wegener's granulomatosis in remission during or after treatment with cyclophosphamide and prednisolone. Relapses and infections were assessed with predefined criteria based on clinical, laboratory, and histopathological findings. Patients were evaluated at least once every three months for signs of disease activity, compliance with the treatment regimen, side effects of the therapy, and evidence of infections. Titers of serum antineutrophil cytoplasmic antibodies were measured serially. RESULTS: Forty-one patients were assigned to receive co-trimoxazole, and 40 to receive placebo. In 8 of the 41 patients in the co-trimoxazole group (20 percent), the drug had to be stopped because of side effects. According to life-table analysis, 82 percent of the patients remained in remission at 24 months, as compared with 60 percent of the patients in the placebo group (relative risk of relapse, 0.40; 95 percent confidence interval, 0.17 to 0.98). There were fewer respiratory tract infections (P = 0.005) and non-respiratory tract infections (P = 0.05) in the co-trimoxazole group than in the placebo group. There were no significant differences in antineutrophil cytoplasmic antibody titers at any time. Proportional-hazards regression analysis identified treatment with co-trimoxazole as an independent factor associated with prolonged disease-free survival and a positive antineutrophil cytoplasmic antibody test at the start of treatment as a risk factor for relapse. CONCLUSIONS: Treatment with co-trimoxazole reduces the incidence of relapses in patients with Wegener's granulomatosis in remission.

Adult↗
PubMed1996

Antineutrophil cytoplasmic antibodies in systemic lupus erythematosus.

Antineutrophil cytoplasmic antibodies (ANCA) with specificity for proteinase-3 (PR3) are associated with Wegener's granulomatosis, and ANCA directed to myeloperoxidase (MPO) with other idiopathic vasculitides. Inflammation of small-sized blood vessels is a hallmark of systemic lupus erythematosus (SLE). We evaluated the prevalence of ANCA in SLE, their antigenic specificities, and their possible relation to clinical disease patterns and activity. Plasma samples from 84 patients with SLE were tested for ANCA during remission. Plasma samples from the 25 patients who relapsed during a follow-up of 32 months were serially analysed for ANCA in a 6 month period preceding and including the relapse. The presence of ANCA was assessed by indirect immunofluorescence (IIF) and ELISA for antibodies to PR3, MPO, lactoferrin (LF), elastase (HLE) and cathepsin-G (CG). We related the presence of ANCA to disease patterns, activity and duration. ANCA by IIF were difficult to interpret dut to the presence of antinuclear antibodies (ANA). By ELISA, we found no anti-PR3 or anti-HLE. Anti-MPO (n = 7), anti-LF (n = 13) and anti-CG (n = 10) were detected, generally in low titres. The presence of ANCA of defined specificity was not associated with specific clinical subsets. The prevalence of ANCA was higher in patients who developed relapses than in those who did not (P < 0.01). However, levels of ANCA did not fluctuate in the period preceding the relapse. ANCA of various specificities occur in SLE. Their presence is not associated with specific clinical disease entities. The higher frequency of ANCA in relapsing patients compared to those who do not relapse may suggest that ANCA are involved in disease expression. Their diagnostic significance is limited.

Adult↗
PubMed1995

Decreased frequency of HLA-DR13DR6 in Wegener's granulomatosis.

The pathogenesis of Wegener's granulomatosis, microscopic polyangiitis and idiopathic rapidly progressive glomerulonephritis (RPGN) is still unclear; in vitro data support both humoral and cellular autoimmune mechanisms. An association of Wegener's granulomatosis with HLA antigens has been described, with conflicting results concerning the antigens involved. We have performed serological HLA typing of patients at two different laboratories within the Netherlands (N = 118 and N = 106,N respectively). A significant decrease in the frequency of HLA-DR13DR6 was present in both patient groups in comparison to controls (chi 2 = 21.9; corrected P value < 0.004 for both groups together). There were no differences in the distribution of HLA-antigens between patients with Wegener's granulomatosis and microscopic polyangiitis, between cANCA (cytoplasmic anti-neutrophil cytoplasmic antibodies) and pANCA (perinuclear ANCA, anti-MPO) positive patients, and between patients with and without relapsing disease.

Aged↗