Maurits Demedts
Katholieke Universiteit Leuven
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Acta Clinica Belgica | 2001
Michiel Thomeer; Maurits Demedts; K. Vandeurzen
Abstract We report the results of a prospective registration of the prevalence of interstitial lung diseases by 20 centres of respiratory medicine in Flanders from January 1992 till July 1996. The 20 centres registered a total of 362 cases. Sarcoidosis (31% with inclusion of stage I, or 22% without stage I), idiopathic pulmonary fibrosis (20%), hypersensitivity pneumonitis (13%) and unclassified forms of interstitial lung diseases (9%) were the most often diagnosed diseases. The mean age of the patients was 52 ± 17 (SD) years, but ranged from 32 ± 10 years in histiocytosis X to 70 ± 13 years in drug induced interstitial lung diseases. The male to female ratio was 1.3 but ranged from 2.3 in interstitial lung diseases due to inhalation of inorganic materials to 0.8 in interstitial lung diseases due to connective tissue disease. The diagnosis was considered certain in 60%, probable in 30% and possible in 10%. In 50% of the cases the diagnosis was proven by biopsy and the most often used biopsy technique was transbronchiolo-alveolar biopsy (40% of biopsies) followed by open lung biopsy (32%). At diagnosis vital capacity was 82±22% pred. (ranging from 92±19% in sarcoidosis to 71±24% in idiopathic pulmonary fibrosis) and CO-diffusing capacity was 77±19% pred. (ranging from 77±19% in sarcoidosis to 41±13% in drug induced pneumonitis). The regional frequency of interstitial lung diseases in Flanders varied widely and was not proportional to the regional distribution of the 20 contributing centres. In conclusion this registration provides interesting information on the occurrence and presentation of the different forms of interstitial lung diseases, although it may still underestimate the real prevalence and incidence of interstitial lung diseases.
Journal of Clinical Oncology | 1999
Johan Vansteenkiste; Sigrid Stroobants; Patrick Dupont; Paul De Leyn; Erik Verbeken; Georges Deneffe; Luc Mortelmans; Maurits Demedts
PURPOSE The amount of radio-labeled (18)F-fluoro-2-deoxy-glucose (FDG) uptake, a measurement of the increased glucose metabolism of non-small-cell lung cancer (NSCLC) cells, has recently been correlated with proliferation capacity. The Standardized Uptake Value (SUV), a semi-quantitative measurement of FDG uptake on positron emission tomography (PET) scan, could thus be of prognostic significance. PATIENTS AND METHODS We analyzed the follow-up of 125 potentially operable NSCLC patients, previously included in three of our prospective PET protocols. Performance status, maximal tumor diameter, tumor-cell type, SUV, and final staging were analyzed for their possible association with survival. RESULTS Sixty-five patients had stage I or II NSCLC, 37 had stage IIIA, and 23 had stage IIIB. Treatment was complete resection in 91 cases. In a univariate analysis, performance status (P =.002), stage (P =.001), tumor diameter (P =.06), tumor-cell type (P =.03), and SUV greater than 7 (P =.001) were correlated with survival. For SUV, group dichotomy with a cut-off SUV of 7 had the best discriminative value for prognosis, both in the total and surgical cohort. A multivariate Cox analysis identified performance status (P =.02), stage (P =.01), and SUV (P =.007) as important for the prognosis. In the surgical group, patients with a resected tumor less than 3 cm had an expected 2-year survival of 86%, if the SUV was below 7, and 60%, if above 7. Nearly all resected tumors larger than 3 cm had SUVs greater than 7 and an expected 2-year survival of 43%. CONCLUSION We conclude that the FDG uptake in primary NSCLC on PET has an important prognostic value and could be complementary to other well-known factors in the decision on adjuvant treatment protocols.
European Journal of Cardio-Thoracic Surgery | 2001
Dirk Van Raemdonck; Kris De Boeck; Hugo Devlieger; Maurits Demedts; Philippe Moerman; Willy Coosemans; Georges Deneffe; Toni Lerut
OBJECTIVE Modern large single institutional reports on pulmonary sequestration (PS) are extremely rare. We were interested in comparing patients with PS referred by our pediatric versus adult pulmonologists. METHODS Hospital notes of all patients operated on between 1978 and 1997 for a congenital broncho-pulmonary malformation were reviewed. In 28 patients, the parenchymal lesion was vascularized by a systemic artery and was separated from the bronchial tree, thus matching the strict definition of PS. Patient characteristics and outcome were analyzed comparing the pediatric group (< or =16 years: n=13; mean age, 3+/-5 years) versus the adult group (>16 years: n=15; mean age, 33+/-13 years). RESULTS No significant differences between both groups were observed in sex, side, type of sequestration, pulmonary venous drainage, associated anomalies, hospital and late outcome, and patients overall score. Patients (n=21) with the intralobar type of sequestration presented significantly more often with an infection when compared with patients (n=7) with the extralobar type (91 versus 14%; P=0.0033). When compared with the pediatric group, patients in the adult group had significantly more respiratory infections (87 versus 38%; P=0.016), and also required a lobectomy more often (67 versus 31%; P=0.056). CONCLUSIONS The extralobar type of sequestration often remains asymptomatic, and is usually an incidental finding during infancy. The intralobar type mostly presents with recurrent infections in adulthood resulting in more lobectomies. We believe these findings support our current policy to remove any pulmonary malformation whenever diagnosed in order to: (1), prevent infection and other potentially serious late complications which may compromise the surgical outcome; and (2), enhance the chance of a parenchymal-sparing resection.
Free Radical Biology and Medicine | 1997
Rob Van Klaveren; Peter Hoet; J L Pype; Maurits Demedts; Benoit Nemery
The purpose of our study was to investigate the effect of oxidative stress or intracellular glutathione (GSH) depletion on gamma-glutamyltransferase (gamma-GT) activity in cultured type II pneumocytes. Twenty-four hours after isolation, primary cultures of rat type II pneumocytes were preincubated with one of four compounds: 15, 30, 60, 125, 250 microM L-buthionine-[SR]-sulfoximine (BSO) for 3 h; 100, 200, 400, 800 microM tertiary-butylhydroperoxide (t-BOOH) for 45 min; 10, 25, 50, 100 microM menadione for 15 min; 100, 1000 microM paraquat for 1 h. GSH levels, H2O2 and O2.- generation were measured immediately after the incubation, gamma-GT activity and GSH levels also up to 24 h or 48 h later. Exposure to BSO led to a persistent GSH depletion without increase in H2O2 or O2.- production, together with a dose and time-dependent increase (doubling) of gamma-GT activity with a nonsignificant increase in gamma-GT mRNA expression 24 h after exposure to BSO. Exposure to 100 microM menadione, which increased H2O2 production, decreased gamma-GT activity. t-BOOH or paraquat did not give rise to a measurable increase in H2O2 or O2.-. Paraquat did not affect initial GSH levels, but increased GSH and decreased gamma-GT activity 24 h later. t-BOOH (400 and 800 microM) initially decreased GSH, and tended to increase GSH 24 h later, 100 and 200 microM increased gamma-GT activity 24 h later, but 800 microM decreased it. Restoration of intracellular GSH levels by addition of GSH to the culture medium completely prevented the increase in gamma-GT activity by BSO, while the addition of catalase or DMTU had no effect. We conclude that at least two effects are operating upon gamma-GT activity: GSH depletion seems to increase gamma-GT activity, while exposure to compounds generating oxidative stress correlates with a decrease in gamma-GT activity.
European Respiratory Journal | 2003
Claudia Put; O. Van den Bergh; Valentine Lemaigre; Maurits Demedts; Geert Verleden
An individualised asthma programme directed at behavioural change was evaluated in asthmatic subjects who reported complaints and impairment, despite adequate medical treatment. Mild-to-moderate asthma patients (n=23) were randomly assigned to a programme or waiting list condition. Outcome measures were: McMaster Asthma Quality of Life Questionnaire, Asthma Symptom Checklist, Negative Emotionality Scale, Knowledge, Attitude and Self-Efficacy Asthma Questionnaire, Adherence Scale, and peak flow measurements. Both groups were evaluated at three consecutive moments, each separated by 3 months; the programme was delivered between the first two evaluations. At onset the patient received a workbook containing information, exercises and homework assignments. Psycho-education, behavioural and cognitive techniques were introduced during six 1‐h individual sessions. Compared with controls the programme group reported less symptoms (obstruction, fatigue), better quality of life (activity, symptoms, emotions), decreased negative affectivity, and increased adherence, immediately after finishing the programme and at 3 months follow-up. All three cognitive variables (knowledge, attitude towards asthma, self-efficacy) and day and night peak flow ratings improved in the programme group but not in the waiting list group. Participation in an individualised programme resulted in improvement of asthma morbidity, and asthma-related behaviour and cognitions, in subjects reporting symptoms and impairment despite adequate medical therapy.
European Respiratory Journal | 2008
Michiel Thomeer; Maurits Demedts; Jürgen Behr; Roland Buhl; Ulrich Costabel; Christopher D. R. Flower; Johny Verschakelen; Francois Laurent; Andrew G. Nicholson; Eric Verbeken; F Capron; Marco Sardina; G Corvasce; Ida Lankhorst
The purpose of the present study was to evaluate the accuracy of the diagnosis of idiopathic pulmonary fibrosis (IPF) by respiratory physicians in six European countries, and to calculate the interobserver agreement between high-resolution computed tomography reviewers and histology reviewers in IPF diagnosis. The diagnosis of usual interstitial pneumonia (UIP) was assessed by a local investigator, following the American Thoracic Society/European Respiratory Society consensus statement, and confirmed when a minimum of two out of three expert reviewers from each expert panel agreed with the diagnosis. The level of agreement between readers within each expert panel was calculated by weighted kappa. The diagnosis of UIP was confirmed by the expert panels in 87.2% of cases. A total of 179 thoracic high-resolution computed tomography scans were independently reviewed, and an interobserver agreement of 0.40 was found. Open or thoracoscopic lung biopsy was performed in 97 patients, 82 of whom could be reviewed by the expert committee. The weighted kappa between histology readers was 0.30. It is concluded that, although the level of agreement between the readers within each panel was only fair to moderate, the overall accuracy of a clinical diagnosis of idiopathic pulmonary fibrosis in expert centres is good (87.2%).
Respiratory Medicine | 2003
Wim Wuyts; Bart Vanaudenaerde; Lieven Dupont; Maurits Demedts; Geert Verleden
Asthma is an inflammatory disease, in which eotaxin, MCP-1 and MCP-3 play a crucial role. These chemokines have been shown to be expressed and produced by IL-1beta-stimulated human airway smooth muscle cells (HASMC) in culture. In the present study we were interested to unravel the IL-1beta-induced signal transduction leading to chemokine production. Using Western blot, we observed an activation of p38 MAPK, JNK kinase and p42/p44 ERK when HASMC were stimulated with IL-1beta. We also observed a significant decrease in the expression and the release of eotaxin, MCP-1 and MCP-3 in the presence of SB203580, an inhibitor of p38 MAPK (71 +/- 6%, P < 0.05, n = 8 and 39 +/- 10% P < 0.01, n = 10 respectively), curcumin, an inhibitor of JNK kinase (83 +/- 4.9% and 88 +/- 3.4% respectively, P < 0.01, n = 4). U0126, an inhibitor of p42/p44 ERK, also produced a significant decrease in chemokine production (46.3 +/- 9%, P < 0.01 n = 10 and 67.8 +/- 12%, P < 0.01, n = 12). Pyrrolydine dithiocarbamate, an inhibitor of NF-kappaB was also able to reduce the eotaxin, MCP-1 and MCP-3 expression and production (50 +/- 13%, P < 0.05, n = 10 and 23 +/- 7%, P < 0.05, n = 12). We conclude that p38 MAPK, JNK kinase, ERK and NF-kappaB are involved in the IL-1beta-induced eotaxin, MCP-1, and MCP-3 expression and release in HASMC.
European Respiratory Journal | 1997
Bertien Buyse; Maurits Demedts; J Meekers; L Vandegaer; Felicien Rochette; L Kerkhofs
This study aimed to determine the relationship between pulmonary function, respiratory muscle function and neurological function in multiple sclerosis (MS). Sixty patients (27 males and 33 females) aged 27-75 yrs (mean +/- SD 48 +/- 12 yrs) were prospectively studied. The Kurtzke Expanded Disability Status Scale (EDSS; range 0-10) score was 6.5 +/- 1.5; and the different Functional Systems Scores (FSS; ranges 0-5 and 0-6) were: pyramidal 3.4 +/- 1.1; brain stem 1.9 +/- 1.2; mental 1.3 +/- 0.9; cerebellar 2.2 +/- 1.0; sphincter 1.8 +/- 1.5; visual 1.4 +/- 1.4; and sensory 2.0 +/- 1.5. Results of lung function tests were: vital capacity (VC) 80 +/- 23% of predicted; single-breath transfer factor of the lung for carbon monoxide (TL, CO, sb) 83 +/- 17% pred; maximal static expiratory mouth pressure (MEP) 30 +/- 16% pred; and maximal static inspiratory mouth pressure (MIP) 47 +/- 23% pred, indicating a marked respiratory muscle dysfunction, with a minor restrictive defect. In 70% of the patients, a transcutaneous oxygen saturation (Stc, O2) of less than 92% at night was found. Comparison of lung function and disability scores showed that the abnormalities in both tended to be correlated to each other, and that this was significant for EDSS versus lung volumes, for most FSS with VC, and also for some FSS with MEP and/or MIP. Duration of disease was significantly correlated with the EDSS, but not with the different FSS scores (with the exception of mental status) and not with lung function. Multiple sclerosis leads to lung function abnormalities attributable to respiratory pump dysfunction.
Respiratory Research | 2009
Jürgen Behr; Maurits Demedts; Roland Buhl; Ulrich Costabel; Richard Dekhuijzen; Henk M. Jansen; William MacNee; Michiel Thomeer; Benoit Wallaert; Francois Laurent; Andrew G. Nicholson; Eric Verbeken; Johny Verschakelen; Paul De Vuyst; Eulogio Rodriguez-Becerra; Ida Lankhorst; Marco Sardina; Gabrielle Boissard; Klinikum der Johannes Gutenberg-Universität; Cdr Flower; Stefano Petruzzelli
BackgroundThe randomized placebo-controlled IFIGENIA-trial demonstrated that therapy with high-dose N-acetylcysteine (NAC) given for one year, added to prednisone and azathioprine, significantly ameliorates (i.e. slows down) disease progression in terms of vital capacity (VC) (+9%) and diffusing capacity (DLco) (+24%) in idiopathic pulmonary fibrosis (IPF). To better understand the clinical implications of these findings we performed additional, explorative analyses of the IFGENIA data set.MethodsWe analysed effects of NAC on VC, DLco, a composite physiologic index (CPI), and mortality in the 155 study-patients.ResultsIn trial completers the functional indices did not change significantly with NAC, whereas most indices deteriorated with placebo; in non-completers the majority of indices worsened but decline was generally less pronounced in most indices with NAC than with placebo. Most categorical analyses of VC, DLco and CPI also showed favourable changes with NAC. The effects of NAC on VC, DLco and CPI were significantly better if the baseline CPI was 50 points or lower.ConclusionThis descriptive analysis confirms and extends the favourable effects of NAC on lung function in IPF and emphasizes the usefulness of VC, DLco, and the CPI for the evaluation of a therapeutic effect. Most importantly, less progressed disease as indicated by a CPI of 50 points or lower at baseline was more responsive to therapy in this study.Trial RegistrationRegistered at http://www.ClinicalTrials.gov; number NCT00639496.
European Journal of Pediatrics | 1998
Johan Hellinckx; Maurits Demedts; K. De Boeck
Pulmonary function tests were obtained in 11 patients with primary ciliary dyskinesia. Their mean age was 15 years (range 6–32). Their pulmonary function was obstructive, with a vital capacity (mean ± SD) of 75% ± 20% predicted, a forced expiratory volume in 1s (FEV1) of 63% ± 20% predicted and a raised residual volume of 169% ± 50% predicted. After inhalation of 200 μg of salbutamol the mean change in FEV1 was + 13.2% ± 9.6% of the baseline value. In the 10 oldest patients, lung function had been measured at regular intervals during 3–20 years. Interestingly, during childhood and adolescence the evolution was not unfavourable: vital capacity increased by 8% ± 20% and FEV1 remained stable (mean change 0.3% ± 12%). Only 2 patients had an unfavourable evolution.ConclusionAt time of diagnosis, patients with primary ciliary dyskinesia have partially reversible obstructive airway disease. During regular follow up and therapy, there is no evidence of a further decline in lung function. Patients with associated immunodeficiency or important damage at the start of therapy may have a worse prognosis.