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Dive into the research topics where D. Posthouwer is active.

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Featured researches published by D. Posthouwer.


Journal of Thrombosis and Haemostasis | 2007

Antiviral therapy for chronic hepatitis C in patients with inherited bleeding disorders: an international, multicenter cohort study

D. Posthouwer; T. T. Yee; M. Makris; K. Fischer; Anja Griffioen; J. J. Van Veen; E. P. Mauser-Bunschoten

Summary.  Background: Hepatitis C is a major co‐morbidity in patients with hemophilia. However, there is little information on the efficacy of antiviral therapy and long‐term follow‐up after treatment.Objectives: To assess the effect of interferon‐based (IFN‐based) therapy on hepatitis C virus (HCV) eradication, to identify determinants associated with treatment response, and to assess the occurrence of end‐stage liver disease (ESLD) after completing antiviral therapy.Patients and methods: In a multicenter cohort study, 295 treatment‐naïve hemophilia patients chronically infected with HCV were included. The effect of therapy was expressed as sustained virological response (SVR). Determinants associated with treatment response were expressed as odds ratios (ORs). Cumulative incidence of ESLD was assessed using a Kaplan–Meier survival table.Results: Among human immunodeficiency virus (HIV) negative patients (n = 235), SVR was 29% (29/101) for IFN monotherapy, 44% (32/72) for IFN with ribavirin, and 63% (39/62) for pegylated IFN (PegIFN) with ribavirin. In patients co‐infected with HIV (n = 60), IFN monotherapy, IFN with ribavirin, and PegIFN with ribavirin eradicated HCV in 7/35 (20%), 1/2 (50%), and 11/23 (48%), respectively. SVR increased with genotype 2 and 3 [OR 11.0, 95% CI: 5.8–20.5], and combination therapy (IFN and ribavirin OR 3.7, 95% CI: 1.7–8.4), PegIFN and ribavirin (OR 4.2, 95% CI: 1.8–9.5). Up to 15 years after antiviral treatment, none of the patients with a SVR relapsed and none developed ESLD. In contrast, among unsuccessfully treated patients the cumulative incidence of ESLD after 15 years was 13.0%.Conclusions: Successful antiviral therapy appears to have a durable effect and reduces the risk of ESLD considerably.


Haemophilia | 2005

Hepatitis C infection among Dutch haemophilia patients : a nationwide cross-sectional study of prevalence and antiviral treatment

D. Posthouwer; I. Plug; J. G. van der Bom; K. Fischer; Frits R. Rosendaal; E. P. Mauser-Bunschoten

Summary.  Hepatitis C is a major co‐morbidity among patients with haemophilia who received inadequately or non‐virus‐inactivated clotting factor concentrates before 1992. The objectives of this study were to investigate the prevalence of hepatitis C and the use of antiviral therapies during the last decade among patients with haemophilia in the Netherlands. We performed a cross‐sectional study and a questionnaire was sent to all 1519 patients known with haemophilia in the Netherlands between 2001 and 2002. The study population for the present study consisted of 771 patients who had received clotting factor products before 1992 of whom 638 reported their hepatitis C status. In total, 441 of the 638 (68%) patients ever had a positive test for hepatitis C virus (HCV); 344 patients (54%) had a current infection, and 97 (15%) had cleared the virus. Among 344 patients currently HCV infected, 111 (32%) had received treatment for hepatitis C, while 34% (33/97) of patients with an infection in the past had been treated for hepatitis C. In 2002 the prevalence of hepatitis C among patients with haemophilia who received clotting factor products before 1992 was 54%. The majority of patients with a current HCV infection had not been treated with antiviral therapy.


Transfusion | 2006

The natural history of childhood-acquired hepatitis C infection in patients with inherited bleeding disorders.

D. Posthouwer; K. Fischer; Karel J. van Erpecum; E. P. Mauser-Bunschoten

BACKGROUND: Although many patients with inherited bleeding disorders have been infected with hepatitis C in early childhood, the natural history of infection in this patient group remains poorly defined.


Journal of Hepatology | 2014

Long-term follow-up of hepatitis C infection in a large cohort of patients with inherited bleeding disorders

Dietje E. Fransen van de Putte; M. Makris; K. Fischer; T. T. Yee; Lisa Kirk; Karel J. van Erpecum; D. Patch; D. Posthouwer; E. P. Mauser-Bunschoten

BACKGROUND & AIMS Patients with inherited bleeding disorders are an interesting group to study the long-term course of chronic hepatitis C virus (HCV) infection, because of their uniform mode of infection and reliable follow-up. Our aim was to assess the long-term occurrence of adverse liver-related events in these patients. METHODS The occurrence and determinants of end-stage liver disease (ESLD) were assessed using retrospective data of 863 HCV infected patients with inherited bleeding disorders from the Netherlands and the UK. RESULTS Median follow-up since HCV infection was 31 years, while 30% of patients had >35 follow-up years. Nineteen percent of patients spontaneously cleared the virus and 81% developed chronic HCV infection. Of the 700 patients with chronic HCV, 90 (13%) developed ESLD. Hepatocellular carcinoma (HCC) was diagnosed in 3% of patients with chronic HCV, 41% of which occurred in the last six years. Determinants of ESLD development were age at infection (hazard ratio (HR) 1.09 per year increase), HIV co-infection (HR 10.85), history of alcohol abuse (HR 4.34) and successful antiviral treatment (HR 0.14). Of the 487 patients who were still alive at the end of follow-up, 49% did not undergo optimal conventional antiviral treatment. CONCLUSIONS After over 30 years of HCV infection, ESLD occurred in a significant proportion of patients with inherited bleeding disorders. HCC appears to be an increasing problem. There is a significant potential for both conventional and new antiviral treatment regimens to try and limit ESLD occurrence in the future.


Haemophilia | 2006

Treatment of chronic hepatitis C in patients with haemophilia: a review of the literature.

D. Posthouwer; E. P. Mauser-Bunschoten; K. Fischer; M. Makris

Summary.  Chronic hepatitis C is a major cause of morbidity and mortality in haemophilia patients. In contrast to studies in the general population, the studies of antiviral therapy in haemophilia patients are limited and often include small numbers of patients. A review of the literature was performed to assess the efficacy of interferon (IFN)‐based therapy for patients with haemophilia chronically infected with hepatitis C virus (HCV). Studies were identified by electronic searches (Medline, Embase) and hand searches in references of key articles. Data of the included studies were pooled, and responses to therapy were stratified according to treatment regimen, HIV co‐infection status, and treatment history. The main outcome was a sustained virological response (SVR) defined as absence of HCV RNA both at the end of treatment and 24‐week post‐treatment. Thirty‐five studies were identified that included 1151 patients. After pooling the data of included patients, the SVR in HIV‐negative treatment naïve patients was 22% for IFN monotherapy, 43% for IFN and ribavirin, and 57% for pegylated IFN and ribavirin, respectively. Re‐treatment with IFN and ribavirin of those who failed to respond to previous IFN monotherapy was successful in 33%. In HCV/HIV‐coinfected patients, response to IFN monotherapy was 8% and to IFN combined with ribavirin 39%. Responses to IFN‐based therapy in patients with haemophilia have been improved over time and are nowadays approximately 50–60%. However, data on haemophilic HCV/HIV‐coinfected patients and in patients who failed to respond to previous therapy are limited and future studies in these specific patient population are necessary.


Journal of Thrombosis and Haemostasis | 2007

Significant liver damage in patients with bleeding disorders and chronic hepatitis C: non‐invasive assessment of liver fibrosis using transient elastography

D. Posthouwer; E. P. Mauser-Bunschoten; K. Fischer; K.J. van Erpecum; R.J. de Knegt

Summary.  Background: Many patients with bleeding disorders have been infected with the hepatitis C virus (HCV), mainly with genotype 1. Antiviral treatment is only effective in 50% of these patients and is often accompanied by serious side effects. Consequently, careful selection of patients for treatment is warranted. Liver biopsies are generally not performed in these patients because of increased bleeding risk and high costs. We therefore assessed liver fibrosis and cirrhosis non‐invasively using liver stiffness measurement (LSM). Methods: We enrolled 124 patients with bleeding disorders and chronic hepatitis C. Liver fibrosis was assessed by LSM using Fibroscan®. In order to assess the validity of LSM in our hands, a separate group of 63 patients without bleeding disorders infected with HCV were evaluated with both LSM and biopsy. Results: In the validation study, liver elasticity was highly correlated with histological fibrosis stage (correlations coefficient 0.73, P < 0.001). Based on LSM, 18% of patients with bleeding disorders and chronic hepatitis C had severe fibrosis, and 17% had cirrhosis after 34 years of infection (range 14–40). However, the prevalence of cirrhosis based on laboratory and ultrasonographic findings was only 7%. Independent risk factors for an increase in LSM were older age at infection, higher body mass index, presence of viral co‐infection, and male gender. Fifteen out of 59 patients (25%) with an apparent indication for treatment (significant fibrosis by LSM) agreed to start antiviral therapy within 3 months. Conclusions: We found an unexpected high number of patients with significant fibrosis and cirrhosis in patients with bleeding disorders and hepatitis C detected by LSM, with considerable impact on the management of the disease.


Haemophilia | 2004

Hepatitis C infection in children with haemophilia: a pilot study

D. Posthouwer; V. M. Wolters; K. Fischer; Roderick H. J. Houwen; H. M. Berg; E. P. Mauser-Bunschoten

Summary.  Many haemophilia patients were infected with hepatitis C virus (HCV) in childhood after transfusion with inadequately or non‐virus inactivated clotting factor products. Limited information is available on the clinical course of HCV infection in children. To assess the clinical consequences of hepatitis C in these young patients we performed a pilot study of 31 patients with haemophilia, infected with HCV before the age of 13. Current median age was 20 years. Nineteen (61%) patients had chronic hepatitis C, whereas the remaining 12 patients spontaneously cleared HCV. The median duration of infection was 17 years. Among patients chronically infected with HCV, an enlarged liver and/or spleen on ultrasound was present in 59%, whereas 63% had abnormal aminotransferases and/or γ‐GT values. In conclusion, 39% of the patients infected in childhood cleared HCV spontaneously. The majority of the patients with chronic hepatitis C had ultrasound and/or laboratory abnormalities and these findings may be associated with the presence of chronic liver disease.


Clinical Infectious Diseases | 2018

Declining Hepatitis C Virus (HCV) Incidence in Dutch Human Immunodeficiency Virus-Positive Men Who Have Sex With Men After Unrestricted Access to HCV Therapy

Anne Boerekamps; Guido E.L. van den Berk; Lauw N Fanny; Eliane M. S. Leyten; Marjo van Kasteren; Arne van Eeden; D. Posthouwer; Mark A.A. Claassen; Anton S Dofferhoff; Dominique W M Verhagen; Wouter F. W. Bierman; Kamilla D. Lettinga; Frank P. Kroon; Corine E. Delsing; Paul H. P. Groeneveld; Robert Soetekouw; Edgar J.G. Peters; Sebastiaan J. Hullegie; Stephanie Popping; David A. M. C. van de Vijver; Charles A. Boucher; Joop E. Arends; Bart J. A. Rijnders

Background Direct-acting antivirals (DAAa) cure hepatitis C virus (HCV) infections in 95% of infected patients. Modeling studies predict that universal HCV treatment will lead to a decrease in the incidence of new infections but real-life data are lacking. The incidence of HCV among Dutch human immunodeficiency virus (HIV)-positive men who have sex with men (MSM) has been high for >10 years. In 2015 DAAs became available to all Dutch HCV patients and resulted in a rapid treatment uptake in HIV-positive MSM. We assessed whether this uptake was followed by a decrease in the incidence of HCV infections. Methods Two prospective studies of treatment for acute HCV infection enrolled patients in 17 Dutch HIV centers, having 76% of the total HIV-positive MSM population in care in the Netherlands. Patients were recruited in 2014 and 2016, the years before and after unrestricted DAA availability. We compared the HCV incidence in both years. Results The incidence of acute HCV infection decreased from 93 infections during 8290 person-years of follow-up (PYFU) in 2014 (11.2/1000 PYFU; 95% confidence interval [CI], 9.1-13.7) to 49 during 8961 PYFU in 2016 (5.5/1000 PYFU; 4.1-7.2). The incidence rate ratio of 2016 compared with 2014 was 0.49 (95% CI, .35-.69). Simultaneously, a significant increase in the percentage positive syphilis (+2.2%) and gonorrhea (+2.8%) tests in HIV-positive MSM was observed at sexual health clinics across the Netherlands and contradicts a decrease in risk behavior as an alternative explanation. Conclusions Unrestricted DAA availability in the Netherlands was followed by a 51% decrease in acute HCV infections among HIV-positive MSM.


Journal of Hepatology | 2016

Boceprevir, peginterferon and ribavirin for acute hepatitis C in HIV infected patients

Sebastiaan J. Hullegie; Mark A.A. Claassen; Guido E.L. van den Berk; Jan T. M. van der Meer; D. Posthouwer; Fanny N. Lauw; Eliane M. S. Leyten; Peter P. Koopmans; C. Richter; Arne van Eeden; Wouter F. W. Bierman; Astrid M. Newsum; Joop E. Arends; Bart J. A. Rijnders

BACKGROUND & AIMS Acute hepatitis C virus infections (AHCV) are prevalent among HIV positive men having sex with men and generally treated with pegylated interferon-alpha (PegIFN) and ribavirin (RBV) during 24weeks. The addition of a protease inhibitor could shorten therapy without loss of efficacy. METHODS We performed an open-label, single arm study to investigate the efficacy and safety of a 12-week course of boceprevir, PegIFN and RBV for AHCV genotype 1 infections in 10 Dutch HIV treatment centers. The primary endpoint of the study was achievement of sustained virological response rate at week 12 (SVR12) in patients reaching a rapid viral response at week 4 (RVR4) and SVR12 in the intent to treat (ITT) entire study population was the most relevant secondary endpoint. RESULTS One hundred twenty-seven AHCV patients were screened in 16 months, of which 65 AHCV genotype 1 patients were included. After spontaneous clearance in six patients and withdrawal before treatment initiation in two, 57 started therapy within 26 weeks after infection. RVR4 rate was 72%. SVR12 rate was 100% in the RVR4 group. SVR12 rate in the ITT group was 86% and comparable to the SVR12 rate of 84% in 73 historical controls treated for 24 weeks with PegIFN and RBV in the same study centers. CONCLUSION With the addition of boceprevir to PegIFN and RBV, treatment duration of AHCV genotype 1 can be reduced to 12 weeks without loss of efficacy. Given the high drug costs and limited availability of interferon-free regimens, boceprevir PegIFN and RBV can be a considered a valid treatment option for AHCV. ClinicalTrials.gov, number NCT01912495.


Haemophilia | 2007

Pegylated interferon and ribavirin combination therapy for chronic hepatitis C in patients with congenital bleeding disorders: a single-centre experience.

D. Posthouwer; K. Fischer; N. De Heusden; E. P. Mauser-Bunschoten

Summary.  Chronic hepatitis C is a major comorbidity in patients with haemophilia. Although the current state‐of‐the‐art therapy consists of pegylated interferon (PegIFN) and ribavirin, there are no reports of the efficacy of this combination in the haemophilia population. The aim of this study was to assess the response and side‐effects of PegIFN and ribavirin in patients with inherited bleeding disorders. Patients with chronic hepatitis C were treated with PegIFN alpha‐2b (1.5 μg kg−1 week−1) and ribavirin (800–1200 mg day−1) for 24 (genotype 2 and 3) or 48 weeks (genotype 1) and followed for an additional 24 weeks. In total, 56 patients were enrolled: 31 (55%) had genotype 1, 12 (21%) genotype 2, and 13 (23%) genotype 3. Ten patients (18%) were HIV co‐infected and seven (13%) had been previously treated with IFN‐α with or without ribavirin. The overall response was 55%. In HIV‐negative and treatment‐naïve patients, the sustained virological response was 70%. Successful treatment was associated with genotypes 2 and 3, absence of HIV, absence of previous IFN treatment, and decrease of hepatitis C virus load at weeks 4 and 12. Although many side‐effects occurred, only a minority (11%) discontinued therapy for this reason. Dose reduction of PegIFN was required in 28% and of ribavirin in 35% of patients. Overall, 22% of patients developed a depression requiring antidepressant drugs and one patient developed psychosis. In conclusion, PegIFN and ribavirin is effective in patients with inherited bleeding disorders. Treatment is safe, but severe side‐effects may occur and warrant close monitoring during therapy.

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M. Makris

University of Sheffield

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Bart J. A. Rijnders

Erasmus University Rotterdam

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Mark A.A. Claassen

Erasmus University Rotterdam

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C. Richter

Erasmus University Medical Center

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