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Dive into the research topics where Akke K. van der Bij is active.

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Featured researches published by Akke K. van der Bij.


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.


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.


The Journal of Infectious Diseases | 2005

GB Virus C Coinfection and HIV-1 Disease Progression: The Amsterdam Cohort Study

Akke K. van der Bij; Nico Kloosterboer; Maria Prins; Brigitte Boeser-Nunnink; Ronald B. Geskus; Joep M. A. Lange; Roel A. Coutinho; Hanneke Schuitemaker

BACKGROUND The effect that GB virus C (GBV-C) coinfection has on human immunodeficiency virus type 1 (HIV-1) disease progression is controversial and therefore was studied in 326 homosexual men from the prospective Amsterdam Cohort Studies who had an accurately estimated date of HIV-1 seroconversion and were followed up for a median period of 8 years. METHODS A first plasma sample, obtained shortly after HIV-1 seroconversion, and a last plasma sample, obtained before 1996, were tested for GBV-C RNA and envelope protein-2 antibodies. The effect that GBV-C has on HIV-1 disease progression was studied by use of time-dependent Cox proportional-hazards models with adjustment for baseline variables and time-updated HIV-1 RNA and CD4(+) cell count. RESULTS Men who lost GBV-C RNA between collection of the first sample and collection of the last sample had a nearly 3-fold-higher risk of HIV-1 disease progression than did men who had never had GBV-C RNA. This effect became much smaller after adjustment for time-updated CD4(+) cell count. CONCLUSION Rather than a positive effect of GBV-C RNA presence, a negative effect of GBV-C RNA loss on HIV-1 disease progression was found, which disappeared after adjustment for time-updated CD4(+) cell count. We therefore hypothesize that GBV-C RNA persistence depends on the presence of a sufficient number of CD4(+) cells--and that the CD4(+) cell decrease associated with HIV-1 disease progression is a cause, not a consequence, of GBV-C RNA loss.


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.


Sexually Transmitted Diseases | 2006

Effectiveness of a risk-based visitor-prioritizing system at a sexually transmitted infection outpatient clinic

Titia Heijman; Akke K. van der Bij; Henry J. C. de Vries; Edwin J. M. van Leent; H. F. J. Thiesbrummel; Han S. A. Fennema

Objective: The objective of this study was to study the efficacy/effectiveness of a risk-based visitor-prioritizing system at a sexually transmitted infection (STI) clinic aimed to improve screening capacity by providing tailored service. Study Design: In April 2004, a prioritizing system was implemented that classifies visitors as high or low risk depending on reported sexual behavior and previous STI events. The high- and low-risk groups are assigned to standard and short screening protocols, respectively. Both protocols include diagnostic testing for syphilis, urogenital gonorrhea, chlamydia, and optional for HIV. To assess the effectiveness of the system, differences in prevalence of STI diagnoses in the standard and short protocol were analyzed by &khgr;2 test. Results: In total, 14,391 visitors (64%) received standard screening and 8,056 visitors (36%) received short screening. The STI prevalence in both groups was 18.1% and 7.6%, respectively (P <0.001); prevalence of HIV was 1.8% and 0.3%, respectively (P <0.001). The sensitivity of the prioritizing system was 74%. Specificity was substantially lower (42%). Conclusions: This prioritizing system is effective in differentiating between visitors at high and low risk for STI, contributing to provision of tailored STI service, increasing efficiency, and client access to STI service.


Journal of Acquired Immune Deficiency Syndromes | 2007

Condom use rather than serosorting explains differences in HIV incidence among men who have sex with men

Akke K. van der Bij; Marion Kolader; Henry J. C. de Vries; Maria Prins; Roel A. Coutinho; Nicole H. T. M. Dukers

Background:HIV incidence is high and increasing among men who have sex with men (MSM) attending the Sexually Transmitted Infection (STI) Outpatient Clinic in Amsterdam but remains low among MSM in the Amsterdam Cohort Studies (ACS). We studied whether sexual behaviors in these 2 groups are consistent with serosorting and if serosorting explains the difference in HIV incidence. Methods:In 2004 to 2006, a survey of sexual behaviors and HIV status regarding up to 4 traceable partners in the prior 6 months was performed in MSM attending the STI Outpatient Clinic (high-risk) and in MSM in the ACS (lower risk). Moreover, pooled information was collected on anonymous partners. We used logistic regression to test whether sexual behaviors are consistent with serosorting and to test whether risk group is associated with having concordant traceable partners among men reporting unprotected anal intercourse (UAI). Results:We included 513 MSM (54% lower risk and 75% HIV-negative). Lower risk and high-risk MSM with concordant traceable partners were more likely to have UAI than MSM with discordant partners or partners of unknown HIV status (P < 0.001). Risk group was not associated with having concordant UAI. Compared with lower risk MSM, however, high-risk MSM frequently had UAI with nonconcordant traceable partners and with anonymous partners. Conclusions:Sexual risk behaviors with traceable partners are consistent with serosorting. Nonetheless, the higher level of UAI with anonymous or nonconcordant traceable partners more likely explains the increasing HIV incidence seen among STI Outpatient Clinic attendees than a difference in serosorting behavior.


Transfusion | 2006

Diversity and origin of hepatitis C virus infection among unpaid blood donors in the Netherlands

Thijs J.W. van de Laar; Marco Koppelman; Akke K. van der Bij; Hans L. Zaaijer; H. Theo M. Cuijpers; Cees L. van der Poel; Roel A. Coutinho; Sylvia M. Bruisten

BACKGROUND: To improve transfusion policy and to increase understanding of the spread of hepatitis C virus (HCV) in the general population, HCV infections among voluntary Dutch blood donors were examined with molecular epidemiologic techniques.


Sexually Transmitted Diseases | 2006

No evidence for a sustained increase in sexually transmitted diseases among heterosexuals in Amsterdam, the Netherlands A 12-year trend analysis at the sexually transmitted disease outpatient clinic Amsterdam

Akke K. van der Bij; Ronald B. Geskus; Han S. A. Fennema; Karin Adams; Roel A. Coutinho; Nicole H. T. M. Dukers

Objectives: Sexually transmitted diseases (STDs) are on the rise, mainly among men having sex with men (MSM). Goal: The goal of this study was to evaluate whether STD increases as seen in MSM are also visible among heterosexuals. Study Design: Attendees of the STD clinic in Amsterdam, The Netherlands, are routinely tested for chlamydia, gonorrhea, and syphilis. Additionally, all women are tested for trichomoniasis. STD time trends of heterosexual attendees between 1994 and 2005 were analyzed by logistic regression and generalized linear models with a negative binomial distribution. Results: The number of consultations doubled since 1994. However, no long-term increase was seen in the number of syphilis and gonorrhea infections. Additionally, the trichomonas prevalence declined. However, the number of chlamydia infections increased over time. Conclusions: Although the number of attendees increased, no evidence for increasing STD incidence was found among heterosexuals. The increase in chlamydia infections can probably be explained by increased screening resulting from increased numbers of attendees.


Blood | 2006

Prognostic value of HIV-1 Gag-specific CD4+ T-cell responses for progression to AIDS analyzed in a prospective cohort study

Christine A. Jansen; Iris M. De Cuyper; Berend Hooibrink; Akke K. van der Bij; Debbie van Baarle; Frank Miedema


European Journal of Public Health | 2008

Low HIV-testing rates and awareness of HIV infection among high-risk heterosexual STI clinic attendees in The Netherlands

Akke K. van der Bij; Nicole H. T. M. Dukers; Roel A. Coutinho; Han S. A. Fennema

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Maria Prins

University of Amsterdam

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