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Dive into the research topics where G. Vreugdenhil is active.

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Featured researches published by G. Vreugdenhil.


Annals of the Rheumatic Diseases | 1990

Anaemia in rheumatoid arthritis: the role of iron, vitamin B12, and folic acid deficiency, and erythropoietin responsiveness.

G. Vreugdenhil; A. W. Wognum; H. G. van Eijk; A. J. G. Swaak

Thirty six patients with rheumatoid arthritis (RA) (25 with anaemia) were studied to establish the role of iron, vitamin B12, and folic acid deficiency, erythropoietin responsiveness, and iron absorption in the diagnosis and pathogenesis of anaemia in RA. Iron deficiency, assessed by stainable bone marrow iron content, occurred in 13/25 (52%), vitamin B12 deficiency in 7/24 (29%), and folic acid deficiency in 5/24 (21%) of the anaemic patients. Only 8/25 (32%) had just one type of anaemia. The iron deficiency of anaemia of chronic disease (ACD) was distinguished by ferritin concentration, which was higher in that group. Mean cell volume (MCV) and mean cell haemoglobin (MCH) were lower in both anaemic groups, but most pronounced in iron deficient patients. Folic acid, and especially vitamin B12 deficiency, masked iron deficiency by increasing the MCV and MCH. Iron absorption tended to be highest in iron deficiency and lowest in ACD, suggesting that decreased iron absorption is not a cause of ACD in RA. No specific causes were found for vitamin B12 or folic acid deficiency. Haemoglobin concentration was negatively correlated with erythrocyte sedimentation rate in the group with ACD. Erythropoietin response was lower in ACD than in iron deficient patients. It was concluded that generally more than one type of anaemia is present simultaneously in anaemic patients with RA. The diagnosis of each type may be masked by another. Studies on pathogenesis of the anaemia are difficult as deficiencies generally coexist with ACD. Disease activity and, possibly, erythropoietin responsiveness are major factors in ACD pathogenesis.


Annals of the Rheumatic Diseases | 1996

Course and characteristics of anaemia in patients with rheumatoid arthritis of recent onset.

H. R. M. Peeters; M. Jongen-Lavrencic; A. N. Raja; H. S. Ramdin; G. Vreugdenhil; F. C. Breedveld; A. J. G. Swaak

OBJECTIVE: To describe the incidence, cause, and course of anaemia in rheumatoid arthritis (RA). METHODS: Medical records of 225 patients who received a diagnosis of RA between 1990 and 1992 were reviewed longitudinally for mention of anaemia. Anaemia was classified as anaemia of chronic disease if ferritin concentrations reflected adequate body iron stores. Among iron depleted anaemic patients, iron deficiency anaemia was identified using the response to iron supplementation. RESULTS: Anaemia developed in 64% of the patients, mostly within 18 months of follow up, but disappeared again in 54% of those patients. The prevalence of anaemia varied from 39% to 53% throughout follow up. Iron depletion was found in 38% of anaemic patients; 40% of them did not recover from their anaemia after iron supplementation and were classified as having anaemia of chronic disease. Anaemia of chronic disease thus caused 77% and iron deficiency anaemia 23% of observed anaemia. Recovery from anaemia occurred in 42% of the patients with anaemia of chronic disease and in 72% of iron depleted patients after iron supplementation. Anaemic patients, particularly those with anaemia of chronic disease, had a significantly greater number of the American College of Rheumatism criteria for RA, significantly more erosive joint damage, and significantly increased concentrations of serum rheumatoid factor than patients without anaemia. CONCLUSION: Anaemia appeared as a frequent and dynamic manifestation. Recovery and recurrence of anaemia was observed throughout follow up, leading to a longstanding and relatively high prevalence of the condition. Iron deficiency was diagnosed frequently and follow up revealed a considerable overlap with anaemia of chronic disease, making this the most important cause of anaemia in RA. Recovery from anaemia occurred more frequently in iron depleted anaemic patients than in those with anaemia of chronic disease. Anaemic patients, particularly those with anaemia of chronic disease, seemed to have a more serious course of their RA compared with non-anaemic patients.


Annals of the Rheumatic Diseases | 1996

Effect of recombinant human erythropoietin on anaemia and disease activity in patients with rheumatoid arthritis and anaemia of chronic disease: a randomised placebo controlled double blind 52 weeks clinical trial.

H. R. M. Peeters; M. Jongen-Lavrencic; G. Vreugdenhil; A. J. G. Swaak

OBJECTIVE: To study whether recombinant human erythropoietin (r-hu-Epo) improves anaemia and reduces disease activity in patients with rheumatoid arthritis and anaemia of chronic disease (ACD). METHODS: A 52 week placebo controlled randomised double blind trial with r-hu-Epo was performed in 70 patients with active rheumatoid arthritis and ACD. Thirty four patients were treated with 240 U kg-1 r-hu-Epo subcutaneously, initially three doses weekly, while 36 patients received placebo. RESULTS: A significant increase of haemoglobin from a median of 112 to 135 g litre-1 occurred in the Epo group within six weeks and could be sustained with reduced doses (median 240 U kg-1 once weekly). Sustained benefit compared to placebo was also apparent by six weeks for disease activity, as indicated by the Paulus 20% response rate. Of patients in the Epo group, 32% eventually showed a Paulus 20% response, compared to 8% of the placebo group (P = 0.016). Significant differences in favour of the Epo group were also observed in the secondary disease activity measures Ritchie index, number of swollen joints, pain score, ESR, and patients global assessment of disease activity. C reactive protein concentrations did not change significantly. CONCLUSIONS: Treatment of ACD in rheumatoid arthritis with r-hu-Epo is effective in restoring normal haemoglobin levels and also exerts a beneficial effect on disease activity.


Rheumatology International | 1990

Anaemia of chronic disease in rheumatoid arthritis - Raised serum interleukin-6 (IL-6) levels and effects of IL-6 and anti-IL-6 on in vitro erythropoiesis

G. Vreugdenhil; B. Löwenberg; H.G. van Eijk; A. J. G. Swaak

SummarySerum and bone marrow from 21 patients with rheumatoid arthritis (RA) were studied in order to establish the pathogenetic role of interleukin-6 (IL-6) in anemia of chronic disease (ACD). Erythroid colony growth, using burst forming units of erythroblasts (BFUe) as a parameter, was impaired in ACD and not in nonanemic RA controls. Serum IL-6 was elevated in ACD and it correlated well with parameters of disease activity such as erythrocyte sedimentation rate and C-reactive protein. IL-6 addition to bone marrow cultures had inconsistent effects while anti-IL-6 addition resulted in impaired erythroid colony growth, suggesting stimulatory effects of IL-6 produced in the medium, which may be masked by simultaneous production of cytokines with suppressive effects. It was concluded that elevated serum IL-6 in ACD reflects disease activity. It probably plays no pathogenetic role in ACD. Its stimulatory effects on erythroid growth might counteract suppressive effects of other interleukins.


Acta Haematologica | 1993

Iron Chelators May Enhance Erythropoiesis by Increasing Iron Delivery to Haematopoietic Tissue and Erythropoietin Response in Iron-Loading Anaemia

G. Vreugdenhil; M. Smeets; R.A. Feelders; H.G. van Eijk

Based on the mode of action of iron chelators, one might expect a decrease in bone marrow iron availability, resulting in worsening of the anaemia in certain types of iron-loading anaemia. However, improvement of anaemia or reduction in transfusion requirements during chelation treatment has been reported in various types of iron-loading anaemia. It is suggested that iron chelators act as mediators facilitating iron release from storage sites and its delivery to haematopoietic tissues. In addition, a reduction of iron stores may upregulate erythropoietin response and bring about a decrease of disease activity in inflammatory disorders, resulting in a haemoglobin rise. Large trials with (oral) iron chelators are required to verify these possible effects.


Annals of Hematology | 1992

Iron stores and serum transferrin receptor levels during recombinant human erythropoietin treatment of anemia in rheumatoid arthritis

G. Vreugdenhil; B. Manger; C. Nieuwenhuizen; R.A. Feelders; H.G. van Eijk; A. J. G. Swaak

SummaryTen rheumatoid arthritis (RA) patients with anemia of chronic disorders (ACD) were treated with recombinant human erythropoietin (r-Hu-Epo) using a dose of 250 U/kg s.c. 3 times a week for 6 weeks, in order to evaluate its effects on the anemia, iron stores, and serum-soluble transferrin receptor (sTfR) levels. All patients showed a rise in hemoglobin (Hb). Median Hb increased from 5.9 (5.5–7.0) at baseline to 6.7 (5.8–7.8) at 3 weeks and to 7.2 (5.9–8.5) mmol/l at 6 weeks during treatment. Ferritin levels decreased significantly during the 6 weeks, and five patients were iron deficient after 6 weeks of treatment. TfR levels increased significantly at 3 and 6 weeks during treatment.These preliminary findings may indicate that r-Hu-Epo is effective in improving ACD in RA. The sTfR rise may be explained by an increase in erythroid precursor cell mass or increased TfR expression and a decrease in tissue iron stores, although direct effects of Epo on TfR regulation cannot be excluded. Large double-blind studies with r-Hu-Epo in patients with RA and ACD are warranted.


The Lancet | 1989

EFFICACY AND SAFETY OF ORAL IRON CHELATOR L1 IN ANAEMIC RHEUMATOID ARTHRITIS PATIENTS

G. Vreugdenhil; A. J. G. Swaak; George J. Kontoghiorghes; H.G. van Eijk

To establish efficacy, safety of 1,2-dimethyl-3-hydroxypyrid-4-one (L1), and a possible increase in erythropoiesis, we have treated 6 patients with definite or classical rhumatoid arthritis and the anaemia of chronic disease


Rheumatology International | 1992

Transferrin microheterogeneity in rheumatoid arthritis

R.A. Feelders; G. Vreugdenhil; G. de Jong; A. J. G. Swaak; H.G. van Eijk

SummaryWe studied the relation between disease activity in rheumatoid arthritis (RA) and the microheterogeneity of transferrin. Using crossed immuno isoelectric focusing, transferrin microheterogeneity patterns were analyzed in sera of healthy individuals, nonanemic RA patients, iron deficient RA patients and RA patients with the anemia of chronic disease (ACD). In all RA groups a significant shift in the microheterogeneity pattern was observed, reflecting increased synthesis of transferrins with highly branched glycan chains. Increased disease activity correlated with both the induction of ACD and the change in transferrin glycosylation, which was, therefore, most pronounced in ACD. Generally, an increased synthesis of glycoproteins is accompanied by alterations in their glycosylation pattern. Since transferrin is a negative acute phase protein, our results indicated that changes in synthetic rates and changes in glycosylation induced in the acute phase response are regulated independently.


Annals of Hematology | 1993

Itraconazole and multidrug resistance: Possible effects on remission rate and disease-free survival in acute leukemia

G. Vreugdenhil; John Raemaekers; B. J. van Dijke; B.E. de Pauw

SummaryItraconazole, a triazole antifungal agent, has been reported to reverse drug resistance against daunorubicin in acute leukemia. In a subanalysis from a double-blind, placebo-controlled trial examining the effects of itraconazole on the prevention of fungal infections in neutropenic patients, we studied the effects of itraconazole on remission rate and disease-free survival in patients with acute lymphoblastic (ALL) and acute myelogenous leukemia (AML) receiving remission induction treatment schedules containing daunorubicin (DNR). Eleven ALL and 17 AML patients received itraconazole and 12 ALL and 25 AML patients were given placebo. Among AML patients the remission rate was slightly higher in the itraconazole group, whereas the disease-free survival was higher mong ALL patients given itraconazole. In AML patients DFS was comparable in both groups but the number of high-risk patients in the itraconazole group was higher. These preliminary results may suggest a role for itraconazole in reversing multidrug resistance. Larger trials, however, are required to substantiate these findings and to correlate them with its in vitro effects on multidrug resistance.


Haematologica | 2010

Dexamethasone compared to prednisolone for adults with acute lymphoblastic leukemia or lymphoblastic lymphoma: final results of the ALL-4 randomized, phase III trial of the EORTC Leukemia Group

Boris Labar; Stefan Suciu; Roelof Willemze; Petra Muus; J.P. Marie; Georges Fillet; Zwi N. Berneman; B. Jaksic; Walter Feremans; Dominique Bron; H. Sinnige; Martin Mistrik; G. Vreugdenhil; R. De Bock; D. Nemet; Caroline Gilotay; Sergio Amadori; T.J.M. de Witte

Background Corticosteroids are a standard component of the treatment of acute lymphoblastic leukemia and lymphoblastic lymphoma. Our aim was to determine whether dexamethasone results in a better outcome than prednisolone. Design and Methods Adult patients with acute lymphoblastic leukemia or lymphoblastic lymphoma were randomized to receive, as part of their induction therapy on days 1–8 and 15–22, either dexamethasone 8 mg/m2 or prednisolone 60 mg/m2. Those who reached complete remission were given two courses of consolidation therapy with high-dose cytarabine and mitoxantrone and methotrexate and asparaginase. Subsequently patients younger than 50 years, with a suitable donor, were to undergo allogeneic stem cell transplantation, whereas the others were planned to receive either an autologous stem cell transplant or high-dose maintenance chemotherapy with prophylactic central nervous system irradiation. Randomization was done with a minimization technique. The primary endpoint was event-free survival and the analyses was conducted on an intention-to-treat basis. Results Between August 1995 and October 2003, 325 patients between 15 to 72 years of age were randomized to receive either dexamethasone (163 patients) or prednisolone (162 patients). After induction and the course of first consolidation therapy, 131 (80.4%) patients in the dexamethasone group and 124 (76.5%) in the prednisolone group achieved complete remission. No significant difference was observed between the two treatment groups with regards to 6-year event-free survival rates (±SE) which were 25.9% (3.6%) and 28.7% (3.5%) in the dexamethasone and prednisolone groups, respectively (P=0.82, hazard ratio 0.97; 95% confidence interval, 0.75–1.25). Disease-free survival after complete remission was also similar in the dexamethasone and prednisolone groups, the 6-year rates being 32.3% and 37.5%, respectively (hazard ratio 1.03; 95% confidence interval 0.76–1.40). The 6-year cumulative incidences of relapse were 49.8% and 53.5% (Gray’s test: P=0.30) while the 6-year cumulative incidences of death were 18% and 9% (Gray’s test: P=0.07). Conclusions In the ALL-4 trial in adult patients with acute lymphoblastic leukemia or lymphoblastic lymphoma, treatment with dexamethasone did not show any advantage over treatment with prednisolone.

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A. J. G. Swaak

Erasmus University Rotterdam

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H.G. van Eijk

Erasmus University Rotterdam

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R.A. Feelders

Erasmus University Rotterdam

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T.J.M. de Witte

Radboud University Nijmegen

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D. Nemet

University Hospital Centre Zagreb

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B. Jaksic

European Organisation for Research and Treatment of Cancer

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Caroline Gilotay

European Organisation for Research and Treatment of Cancer

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Dominique Bron

Université libre de Bruxelles

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