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Dive into the research topics where Henry J. C. de Vries is active.

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Featured researches published by Henry J. C. de Vries.


The Journal of Infectious Diseases | 2007

Increase in HCV incidence among men who have sex with men in Amsterdam most likely caused by sexual transmission

Thijs J.W. van de Laar; Akke K. van der Bij; Maria Prins; Sylvia M. Bruisten; Kees Brinkman; Thomas Ruys; Jan T. M. van der Meer; Henry J. C. de Vries; Jan-Willem Mulder; Michiel A. van Agtmael; Suzanne Jurriaans; Katja C. Wolthers; Roel A. Coutinho

We retrospectively screened 1836 men who have sex with men (MSM) participating in the Amsterdam Cohort Studies (1984-2003) for hepatitis C virus (HCV) antibodies. HCV incidence was 0.18/100 person-years (PY) in human immunodeficiency virus (HIV)-positive MSM (8/4408 PY [95% confidence interval {CI}, 0.08-0.36]) but was 0/100 PY in MSM without HIV (0/7807 PY [95% CI, 0.00-0.05]). After 2000, HCV incidence among HIV-positive men increased 10-fold to 0.87/100 PY (5/572 PY [95% CI, 0.28-2.03]). Additional hospital cases (n=34) showed that MSM in Amsterdam who acquired HCV infection after 2000 reported high rates of ulcerative sexually transmitted infections (59%) and rough sexual techniques (56%), denied injection drug use, and were infected mainly with the difficult-to-treat HCV genotypes 1 (56%) and 4 (36%). Phylogenetic analysis showed 3 monophyletic clusters of MSM-specific HCV strains. The emergence of an MSM-specific transmission network suggests that HIV-positive MSM with high-risk sexual behaviors are at risk for sexually acquired HCV. Targeted prevention and routine HCV screening among HIV-positive MSM is needed to deter the spread of HCV.


Nature Genetics | 2012

Whole-genome analysis of diverse Chlamydia trachomatis strains identifies phylogenetic relationships masked by current clinical typing

Simon R. Harris; Ian N. Clarke; Helena M. B. Seth-Smith; Anthony W. Solomon; Lesley T. Cutcliffe; Peter Marsh; Rachel J. Skilton; Martin J. Holland; David Mabey; Rosanna W. Peeling; David A. Lewis; Brian G. Spratt; Magnus Unemo; Kenneth Persson; Carina Bjartling; Robert C. Brunham; Henry J. C. de Vries; Servaas A. Morré; Arjen G. C. L. Speksnijder; Cécile Bébéar; Maïté Clerc; Bertille de Barbeyrac; Julian Parkhill; Nicholas R. Thomson

Chlamydia trachomatis is responsible for both trachoma and sexually transmitted infections, causing substantial morbidity and economic cost globally. Despite this, our knowledge of its population and evolutionary genetics is limited. Here we present a detailed phylogeny based on whole-genome sequencing of representative strains of C. trachomatis from both trachoma and lymphogranuloma venereum (LGV) biovars from temporally and geographically diverse sources. Our analysis shows that predicting phylogenetic structure using ompA, which is traditionally used to classify Chlamydia, is misleading because extensive recombination in this region masks any true relationships present. We show that in many instances, ompA is a chimera that can be exchanged in part or as a whole both within and between biovars. We also provide evidence for exchange of, and recombination within, the cryptic plasmid, which is another key diagnostic target. We used our phylogenetic framework to show how genetic exchange has manifested itself in ocular, urogenital and LGV C. trachomatis strains, including the epidemic LGV serotype L2b.


Clinical Infectious Diseases | 2006

Diagnostic and clinical implications of anorectal lymphogranuloma venereum in men who have sex with men: a retrospective case-control study.

Akke K. van der Bij; Joke Spaargaren; Servaas A. Morré; Han S. A. Fennema; Adrian Mindel; Roel A. Coutinho; Henry J. C. de Vries

BACKGROUND Recently, outbreaks of anorectal lymphogranuloma venereum (LGV) have occurred among men who have sex with men (MSM). This study identifies risk factors and clinical predictors of LGV to determine the implications for clinical practice. METHODS The Chlamydia trachomatis serovars for all MSM who had anorectal chlamydia diagnosed at a sexually transmitted infection clinic in Amsterdam, The Netherlands, in 2002 and 2003 were retrospectively typed; 87 persons were infected with C. trachomatis serovar L2b and received a diagnosis of LGV. MSM infected with C. trachomatis serovars A-K and who thus had non-LGV anorectal chlamydia (n = 377) and MSM who reported having receptive anorectal intercourse but who did not have anorectal chlamydia (n = 2677) served as 2 separate control groups. Risk factors and clinical predictors were analyzed by multivariate logistic regression. Receiver operating characteristic curves were used to determine clinical relevance. RESULTS HIV seropositivity was the strongest risk factor for LGV (odds ratio for patients with LGV vs. those with non-LGV chlamydia, 5.7 [95% confidence interval, 2.6-12.8]; odds ratio for patients with LGV vs. control subjects without chlamydia, 9.3 [95% confidence interval, 4.4-20.0]). Proctoscopic findings and elevated white blood cell counts in anorectal smear specimens were the only clinically relevant predictors for LGV infection (area under the curve of the receiver operating characteristic curve, > 0.71). Use of these 2 parameters and HIV infection status provided the highest diagnostic accuracy (for MSM with anorectal chlamydia, the area under the curve was > 0.82; sensitivity and specificity were 89% and 50%, respectively). CONCLUSIONS LGV testing is recommended for MSM with anorectal chlamydia. If routine LGV serovar typing is unavailable, we propose administration of syndromic LGV treatment for MSM with anorectal chlamydia and either proctitis detected by proctoscopic examination, > 10 white blood cells/high-power field detected on an anorectal smear specimen, or HIV seropositivity.


Emerging Infectious Diseases | 2005

Real-time polymerase chain reaction to diagnose lymphogranuloma venereum

Servaas A. Morré; Joke Spaargaren; J. S. A. Fennema; Henry J. C. de Vries; Roel A. Coutinho; A. Salvador Peña

To the Editor: An outbreak of rectal lymphogranuloma venereum (LGV) has been detected in the Netherlands among men who have sex with men (1–4). More cases of LGV in other European countries such as Belgium, France, and the United Kingdom have been reported, and the first cases have been detected in the United States as well. This infection is encountered not only by clinicians who treat sexually transmitted diseases but also by gastroenterologists. Both the European Surveillance of Sexually Transmitted Infections (http://www.essti.org) and the Centers for Disease Control and Prevention (http://www.cdc.gov) are working on outbreak warning and response systems to increase the awareness and the direct management of the LGV outbreak (5,6). Different approaches have been described to diagnose LGV infections (Figure). The first 3 approaches have serious disadvantages: cell culture is rarely available in routine diagnostic settings, polymerase chain reaction (PCR)-based restriction fragment length polymorphism (RFLP) analysis (usually nested PCR approaches are used) needs post-PCR restriction enzyme profiling, and sequencing requires additional analyses of sequence data to identify the Chlamydia trachomatis serovar responsible for infection. In addition, all 3 techniques are time consuming (at least 1–4 days to get a result), laborious, and require specially trained personnel in a sophisticated laboratory setting. Therefore, we developed a real-time PCR approach (TaqMan and Rotorgene) that can easily identify LGV strains in 2 hours with equipment that is available in almost all diagnostic settings. Figure Diagnosis of lymphogranuloma venereum. MIF, microimmunofluorescence; STI, sexually transmitted infection; PCR, polymerase chain reaction; RFLP, restriction fragment length polymorphism; PAA, poly acrylamide; BLAST, basic local alignment search tool. We used the polymorphic membrane protein H gene (pmp gene) as a PCR target because it has a unique gap in LGV strains of C. trachomatis, compared to other serovars, which makes it highly specific. The following primers and probes were selected: LGV-F 5´ CTG TGC CAA CCT CAT CAT CAA 3´, LGV-R 5´ AGA CCC TTT CCG AGC ATC ACT 3´, and LGV MGB-probe 6-FAM-CCT GCT CCA ACA GT. Real-time PCR conditions (20-μL format) for TaqMan were as follows: 2× TaqMan Universal Mastermix (Applied Biosystems, Foster City, CA, USA), 18 pmol each primer, 0.2 μmol/L probe, and 2 μL (LGV L2) DNA or clinical sample; 2 min at 50°C, 10 min at 95°C, and 40 cycles of 15 sec at 95°C and 1 min at 60°C. Conditions for Rotorgene were as follows: 10× buffer (Hoffman-La Roche Ltd, Basel, Switzerland), 10 pmol each primer, 0.04 μmol/L probe, 2 μL (LGV L2) DNA or clinical sample; 2 min at 50°C, 10 min at 95°C, and 45 cycles of 15 sec at 95°C and 1 min at 60°C. By using a previously described serial dilution of LGV L2 (7), sensitivity was assessed as 0.01 inclusion-forming units for both real-time PCR assays. To determine specificity, we tested different C. trachomatis serovars and serovariants A, B, Ba, C, D, Da, D-, E, F, G, Ga, H, I, Ia, I-, J, Jv, K, L1, L2, L2b, L3, C. muridarum (MoPn), C. pneumoniae, C. pecorum, C. psittaci, and 32 other microorganisms that normally reside in the human perianal and urogenital region and in the oropharynx. These organisms included gram-positive and gram-negative bacteria and yeast: Acinetobacter baumannii, Campylobacter jejuni, Candida albicans, other yeast, Enterobacter agglomerans, Enterococcus faecalis, Escherichia coli, Streptococcus spp., Haemophilus influenzae, Klebsiella pneumoniae, Mycoplasma spp., Neisseria meningitidis, Pasteurella spp., Pseudomonas aeruginosa, Salmonella enteritidis, Shigella sonnei, Staphylococcus aureus, and others. Only LGV strains L1, L2, L2b, and L3 tested positive in both the TaqMan and Rotorgene assays, which shows the analytical specificity of real-time PCR. Subsequently, we determined in a blinded setting the presence of LGV in a selected group of patients (clinical spectrum and epidemiology described elsewhere [8]) according to C. trachomatis–positive rectal swab (Chlamydia 2SP Collection & Transport Kit [Quelab] by commercially available PCR (COBAS AMPLICOR, Hoffman-La Roche Ltd). By using the 2 reference standard techniques to type C. trachomatis serovars (PCR-based RFLP of the omp1 gene or sequencing the variable segment 2 [VS-2] of the omp1 gene) (9,10) with DNA isolated from rectal swab specimens (standard isopropanol DNA isolation method), we identified 28 of 125 men as LGV-positive. These 28 samples were also positive in both the TaqMan and Rotorgene assays. We also identified 2 additional LGV infections, which were initially typed and then retested as single-strain infections with serovars E and D by both PCR-based RFLP analysis and VS-2 sequencing. This discrepancy is most likely due to a double infection, which will, in most cases, result in the preferential amplification of 1 strain in the omp1 PCR and PCR-based sequencing methods; in the TaqMan and Rotorgene assays, only LGV strains can be amplified. Whether this outbreak is partially technically driven must be assessed in the future by retrospectively investigating the presence of these LGV infections in men who have sex with men and the presence of the L2b strain in the past, since at present only LGV infections from 2003 to 2005 have been investigated.


Antimicrobial Agents and Chemotherapy | 2008

Pharmacokinetics of Miltefosine in Old World Cutaneous Leishmaniasis Patients

Thomas P. C. Dorlo; Pieter P.A.M. van Thiel; Alwin D. R. Huitema; Ron J. Keizer; Henry J. C. de Vries; Jos H. Beijnen; Peter J. de Vries

ABSTRACT The pharmacokinetics of miltefosine in leishmaniasis patients are, to a great extent, unknown. We examined and characterized the pharmacokinetics of miltefosine in a group of patients with Old World (Leishmania major) cutaneous leishmaniasis. Miltefosine plasma concentrations were determined in samples taken during and up to 5 months after the end of treatment from 31 Dutch military personnel who contracted cutaneous leishmaniasis in Afghanistan and were treated with 150 mg miltefosine/day for 28 days. Samples were analyzed with a validated liquid chromatography-tandem mass spectrometry assay with a lower limit of quantification (LLOQ) of 4 ng/ml. Population pharmacokinetic modeling was performed with nonlinear mixed-effect modeling, using NONMEM. The pharmacokinetics of miltefosine could best be described by an open two-compartment disposition model, with a first elimination half-life of 7.05 days and a terminal elimination half-life of 30.9 days. The median concentration in the last week of treatment (days 22 to 28) was 30,800 ng/ml. The maximum duration of follow-up was 202 days after the start of treatment. All analyzed samples contained a concentration above the LLOQ. Miltefosine is eliminated from the body much slower than previously thought and is therefore still detectable in human plasma samples taken 5 to 6 months after the end of treatment. The presence of subtherapeutic miltefosine concentrations in the blood beyond 5 months after treatment might contribute to the selection of resistant parasites, and moreover, the measures for preventing the teratogenic risks of miltefosine treatment should be reconsidered.


Emerging Infectious Diseases | 2005

New lymphogranuloma venereum Chlamydia trachomatis variant, Amsterdam.

Joke Spaargaren; Han S. A. Fennema; Servaas A. Morré; Henry J. C. de Vries; Roel A. Coutinho

We retrospectively conducted a study of men who have sex with men who visited the Amsterdam, the Netherlands, sexually transmitted diseases clinic from January 2002 to December 2003 and had rectal Chlamydia trachomatis infections. We found that symptomatic (73%) as well as asymptomatic (43%) patients were infected with a new C. trachomatis LGV variant.


Journal of Clinical Microbiology | 2005

Quantitative Nucleic Acid Sequence-Based Assay as a New Molecular Tool for Detection and Quantification of Leishmania Parasites in Skin Biopsy Samples

Wendy F. van der Meide; Gerard J. Schoone; William R. Faber; Jim E. Zeegelaar; Henry J. C. de Vries; Yusuf Özbel; Rudy F. M. Lai A Fat; Leíla I. A. R. C. Coelho; Masoom Kassi; Henk D. F. H. Schallig

ABSTRACT Currently available methods for the diagnosis of cutaneous leishmaniasis (CL) have low sensitivities or are unable to quantify the number of viable parasites. This constitutes a major obstacle for the diagnosis of the disease and for the study of the effectiveness of treatment schedules and urges the development of improved detection methods. In this study, quantitative nucleic acid sequence-based amplification (QT-NASBA) technology was used to detect and quantify Leishmania parasites in skin biopsy samples from CL patients. The assay is based on the detection of a small subunit rRNA (18S rRNA), which may allow for the detection of viable parasites. The QT-NASBA assay was evaluated using in vitro-cultured promastigotes and amastigotes and 2-mm skin biopsy samples from Old and New World CL patients. The study demonstrated that the lower detection limit of the QT-NASBA was two parasites per biopsy sample. Parasites could be quantified in a range of 2 to 11,300,000 parasites per biopsy sample. The QT-NASBA could detect levels of parasites 100-fold lower than those detected by conventional PCR. Test evaluation revealed that the QT-NASBA had a sensitivity of 97.5% and a specificity of 100% in the present study. The QT-NASBA is a highly sensitive and specific method that allows quantification of both Old and New World Leishmania parasites in skin biopsy samples and may provide an important tool for diagnosis as well as for monitoring the therapy of CL patients.


American Journal of Clinical Dermatology | 2015

Cutaneous Leishmaniasis: Recent Developments in Diagnosis and Management

Henry J. C. de Vries; Sophia H. Reedijk; Henk D. F. H. Schallig

This review focuses on recent developments in the diagnosis, treatment, management, and strategies for the prevention and control of cutaneous leishmaniasis (CL) caused by both Old and New World Leishmania species. CL is caused by the vector-borne protozoan parasite Leishmania and is transmitted via infected female sandflies. The disease is endemic in more than 98 countries and an estimated 350 million people are at risk. The overall prevalence is 12 million cases and the annual incidence is 2–2.5 million. The World Health Organization considers CL a severely neglected disease and a category 1 emerging and uncontrolled disease. The management of CL differs from region to region and is primarily based on local experience-based evidence. Most CL patients can be treated with topical treatments, but some Leishmania species can cause mucocutaneous involvement requiring a systemic therapeutic approach. Moreover, Leishmania species can vary in their sensitivity to available therapeutic options. This makes species determination critical for the choice of treatment and the clinical outcome of CL. Identification of the infecting parasite used to be laborious, but now the Leishmania species can be identified relatively easy with new DNA techniques that enable a more rational therapy choice. Current treatment guidelines for CL are based on poorly designed and reported trials. There is a lack of evidence for potentially beneficial treatments, a desperate need for large well-conducted studies, and standardization of future trials. Moreover, intensified research programs to improve vector control, diagnostics, and the therapeutic arsenal to contain further incidence and morbidity are needed.


Lancet Oncology | 2013

Comparison of imiquimod, topical fluorouracil, and electrocautery for the treatment of anal intraepithelial neoplasia in HIV-positive men who have sex with men: an open-label, randomised controlled trial.

Olivier Richel; Henry J. C. de Vries; Carel J. M. van Noesel; Marcel G. W. Dijkgraaf; Jan M. Prins

BACKGROUND Anal cancer is an increasing issue in HIV-positive men who have sex with men (MSM). Screening for its precursor, anal intraepithelial neoplasia (AIN), is subject of discussion. Current treatment options are suboptimum and have not been compared in a prospective trial. We compared efficacy and side-effects of imiquimod, topical fluorouracil, and electrocautery for the treatment of AIN. METHODS In this open-label randomised trial, we included HIV-positive MSM older than 18 years visiting the HIV outpatient clinic of the Academic Medical Center, Amsterdam, Netherlands. Patients with histologically confirmed AIN were randomly assigned to receive either 16 weeks of imiquimod (three times a week), 16 weeks of topical fluorouracil (twice a week), or monthly electrocautery for 4 months. Randomisation was done with random block sizes of three and six, stratified for AIN grade (AIN grades 1, 2, or 3) and AIN location (peri-anal or intra-anal). Participants were assessed by high-resolution anoscopy 4 weeks after treatment. Responding patients returned for follow-up 24 weeks, 48 weeks, and 72 weeks after treatment. The primary endpoint was histological resolution of AIN measured 4 weeks after treatment and AIN recurrence at week 24, week 48, and week 72 after treatment. The primary analysis was done in a modified intention-to-treat population, including all patients who had received their assigned treatment at least once. The trial is registered at the Netherlands Trial Register, number NTR1236. FINDINGS Between Aug 12, 2008, and Dec 1, 2010, we screened 388 HIV-positive MSM for AIN by high resolution anoscopy. Of the 246 (63%) patients who had AIN, 156 (63%) were randomly assigned to either receive imiquimod (54 patients), topical fluorouracil (48 patients), or electrocautery (46 patients) following withdrawing of consent by eight patients. Modified intention-to-treat analysis showed a complete response in 13 (24%, 95% CI 15-37) patients in the imiquimod group, eight (17%, 8-30) of patients in the fluorouracil group, and 18 (39%, 26-54) of patients in the electrocautery group (p=0·027). At week 24, 11 (22%) of 50 responders had recurrence; at week 48, 22 (46%) of 48 had recurred; and at week 72, 30 (67%) of 45 had recurred. Recurrence was observed at 72 weeks in 10 (71%) of 14 patients treated with imiquimod, seven (58%) of 12 patients treated with fluorouracil, and 13 (68%) of 19 patients treated with electrocautery. Grade 3-4 side-effects were noted in 23 (43%) of 53 patients in the imiquimod group, 13 (27%) of 48 patients in the fluorouracil group, and eight (18%) patients in the electrocautery group (p=0·019). The most common side-effects were pain, bleeding, and itching. Seven serious adverse events occurred, all not related to the study. INTERPRETATION Electrocautery is better than imiquimod and fluorouracil in the treatment of AIN, but recurrence rates are substantial. FUNDING Anna Maurits de Cock foundation provided funding for the video colposcope.


Sexually Transmitted Diseases | 2008

Lymphogranuloma venereum proctitis in men who have sex with men is associated with anal enema use and high-risk behavior

Henry J. C. de Vries; Akke K. van der Bij; J. S. A. Fennema; Colette Smit; Frank de Wolf; Maria Prins; Roel A. Coutinho; Servaas A. Morré

Objectives: In the industrialized world, lymphogranuloma venereum proctitis (LGVP) has been reported only in men who have sex with men. Factors responsible for the outbreak remain to be elucidated. GOAL: The goal of the present work was to elucidate risk factors associated with LGVP. Study Design: The study design comprised a cross-sectional study including 32 men with LGVP and 93 men without LGVP (22 with gonorrheal proctitis, 30 with a non-LGV chlamydial proctitis, and 41 with proctitis of unknown etiology). Factors associated with LGVP were analyzed by (multinomial) logistic regression. Results: Comparing men with LGVP with men without LGVP, factors significantly associated with higher risk of LGVP in multivariate analyses were as follows: anal enema use [odds ratio (OR): 7.8, 95% confidence interval (CI): 2.6–23.2], having sex on sex parties (OR: 5.7, 95% CI: 1.5–21.8), and having sex with human immunodeficiency virus-positive partners (OR: 3.2, 95% CI: 1.1–9.3). Evaluating the 4 proctitis groups separately in a multinomial logistic regression model, similar associations between anal enema use and LGVP were found. Men with non-LGV chlamydial proctitis showed less risk behavior than men with LGVP. No substantial difference in risk behavior was found, except for attending sex parties, between men with LGVP, and gonorrheal proctitis or proctitis of unknown etiology. Conclusions: Apart from men with LGVP, men with gonorrheal proctitis or proctitis of unknown etiology exhibit high risk behavior. Enema use seems to play a key role in transmission of LGVP, and needs further investigation.

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Jan M. Prins

University of Amsterdam

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Maria Prins

University of Amsterdam

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Alje P. van Dam

Leiden University Medical Center

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