Syphilis reinfections pose problems for syphilis diagnosis in Antwerp, Belgium - 1992 to 2012

Persons with multiple syphilis reinfections may play an important role in syphilis transmission. We analysed all syphilis tests carried out for people attending the HIV/sexually transmitted infection (STI) clinic at the Institute of Tropical Medicine, Antwerp, Belgium, from 1992 to 2012 to evaluate the extent to which syphilis reinfections were contributing to the syphilis epidemic in Antwerp. We then characterised the features of the syphilis infections in individuals with five or more episodes of syphilis. A total of 729 syphilis episodes were diagnosed in 454 persons. The majority of syphilis episodes occurred in people who had more than one episode of syphilis (445/729; 61%). A total of 10 individuals had five or more episodes of syphilis diagnosed over this period. All were men who have sex with men, HIV positive and on antiretroviral therapy. They had a total of 52 episodes of syphilis diagnosed and treated. In 38/42 of the episodes of repeat syphilis in these 10 individuals, they presented without any signs or symptoms of syphilis. Given that the majority of cases of incident syphilis in our clinic were persons with reinfections and that they frequently presented without signs of symptoms of syphilis, there is a strong case for frequent and repeated screening in all persons with a diagnosis of syphilis.

Incidence of HCV and sexually transmitted diseases among hiv positive msm in antwerp, belgium, 2001-2011

Recurrent Sexually Transmitted Infections (STIs) are an indication of unsafe sexual practices and may be associated with HCV-infection among HIV-positive men who have sex with men. In a retrospective study we analysed the laboratory data of 99 HIV-positive MSM who acquired HCV during the observation period (cases) and 176 HIV-positive MSM who remained HCV negative during the observation period (controls), all followed at the HIV/STI-clinic in Antwerp, Belgium. All laboratory confirmed STI-episodes were recorded since the date of first consultation at our clinic, until the date of HCV-diagnosis of the cases. The HCV incidence varied between 0.24 (2001) and 1.36 (2011) new cases per hundred person-years, with a peak of 2.93 new cases per hundred person-years in 2009. The number of STI-episodes per person-year follow-up was significantly higher for the cases as compared to the controls for syphilis, non-LGV and LGV Chlamydia infections (p < 0.005). When considering the incidence of STIs that occurred 1 year prior to HCV conversion, all laboratory confirmed STIs remained more frequent among cases, but only the difference in syphilis incidence was statistically significant (p < 0.01). Recurrent STIs among HIV positive MSM should be considered as a behavioural and biological risk factor for acquiring HCV and should lead to intensified screening for HCV and counselling of the patient.

Sexually transmitted infections: what's new?

Since the beginning of the third millennium the incidence of Sexually Transmitted Infections (STIs) is rising in Europe and in Belgium, and this after a steady decline in the second half of last century. It concerns new or lesser known diseases such as Hepatitis C and Lymphogranuloma venereum (LGV) and 'old' diseases such as gonorrhoea and syphilis, occurring in specific risk groups. In this article we give an update of the diagnostic means and therapeutic challenges that are of interest for the clinician. Besides these (re)-emerging diseases we touch on Human Papillomavirus (HPV) and Herpes Simplex (HSV). This selection of diseases is based on the daily experience of the clinicians working in the STI clinic of the Institute of Tropical Medicine in Antwerp. Data and clinical guidelines are derived from the Scientific Institute of Public Health in Brussels, the European and American Centers for Disease Control and Prevention, and the Guidelines of the Flemish Agency for Care and Health. New evolutions in diagnostics, prevention and treatment options make it necessary to regularly update the knowledge of this group of diseases, especially when they are complicated by HIV co-infection. As the incidence of neither HIV nor STIs seem to decrease in Belgium and Europe, it remains necessary to stay aware of the state-of-the-art management.

Hepatitis C virus infection in HIV-infected men who have sex with men: sustained rising incidence in Antwerp, Belgium, 2001–2009

During the last decade, outbreaks of acute hepatitis C virus (HCV) infection have been reported among human immunodeficiency virus (HIV)-infected men who have sex with men (MSM) in several European countries. To study this emerging infection in MSM in Antwerp, Belgium, we reviewed all cases of newly acquired HCV infection in HIV-positive MSM followed from 2001 to 2009 at the HIV/sexually transmitted infection (STI) reference clinic of the Institute of Tropical Medicine in Antwerp. Newly acquired HCV infection was considered as certain or probable according to local definitions. During the study period, 69 episodes of newly acquired HCV infection (40 certain and 29 probable) were diagnosed in 67 HIV-infected MSM. In only 10 episodes (14%) were the patients symptomatic. The annual incidence of HCV infection in our population of HIV-infected MSM rose steadily from 0.2% in 2001 to 1.51% in 2008, and then peaked to 2.9% in 2009. For 60 episodes (87%), another STI (mainly syphilis and lymphogranuloma venereum) had been diagnosed within the six months before the diagnosis of HCV infection. All but one patient with available genotyping (n=54) were found to be infected with the difficult-to-treat HCV genotypes 1 or 4. Our results therefore demonstrate the rising incidence of HCV infection in HIV-positive MSM in Antwerp, since 2001, which reached an alarming level in 2009. Targeted awareness campaigns and routine screening are urgently needed to limit further HCV spread and its expected long-term consequences.

Hepatitis C virus infection in HIV-infected men who have sex with men: sustained rising incidence in Antwerp, Belgium, 2001-2009

During the last decade, outbreaks of acute hepatitis C virus (HCV) infection have been reported among human immunodeficiency virus (HIV)-infected men who have sex with men (MSM) in several European countries. To study this emerging infection in MSM in Antwerp, Belgium, we reviewed all cases of newly acquired HCV infection in HIV-positive MSM followed from 2001 to 2009 at the HIV/sexually transmitted infection (STI)reference clinic of the Institute of Tropical Medicine in Antwerp. Newly acquired HCV infection was considered as certain or probable according to local definitions. During the study period, 69 episodes of newly acquired HCV infection (40 certain and 29 probable) were diagnosed in 67 HIV-infected MSM. In only 10 episodes (14%) were the patients symptomatic. The annual incidence of HCV infection in our population of HIV-infected MSM rose steadily from 0.2% in 2001 to 1.51% in 2008, and then peaked to 2.9% in 2009. For 60 episodes (87%), another STI (mainly syphilis and lymphogranuloma venereum) had been diagnosed within the six months before the diagnosis of HCV infection. All but one patient with available genotyping (n=54) were found to be infected with the difficult to-treat HCV genotypes 1 or 4. Our results therefore demonstrate the rising incidence of HCV infection in HIV-positive MSM in Antwerp, since 2001, which reached an alarming level in 2009. Targeted awareness campaigns and routine screening are urgently needed to limit further HCV spread and its expected long-term consequences.

Chlamydia trachomatis prevalence and sexual behaviour among female adolescents in Belgium

OBJECTIVES

To determine prevalence and risk factors of Chlamydia trachomatis among female secondary school students and to develop potential selective screening strategies.

METHODS

A cross sectional survey was conducted in the 17 school medical centres in Antwerp municipality, Belgium. All female students of forms 5 or 6, who were due for their medical check up during the school year 1996-7, were invited to participate. A self administered questionnaire on general and sexual behaviour, and a first void urine sample were collected. The urine specimen was tested for C trachomatis with ligase chain reaction assay, and positive tests were confirmed with polymerase chain reaction assays.

RESULTS

2784 female students participated in the study. Their median age was 17, and 52% of them reported having sexual intercourse at least once. The prevalence of C trachomatis among sexually active women was 1.4%. Factors significantly associated with infection in multivariate analysis were number of lifetime partners, genital complaints of partner, type of secondary school, and a history of pregnancy. Selective screening of those women who are at highest risk for infection would have detected 90% of all infections, and require testing of 14% to 18% of the population.

CONCLUSIONS

The prevalence of C trachomatis was relatively low among female secondary school students in Antwerp, but unsafe sex practices were evident because of the high number of unplanned pregnancies. Selective screening strategies with a high sensitivity can be proposed, but should be assessed for acceptability, feasibility, and cost.

CD8+ cells and not CD4+ T cells are hyporesponsive to CD28- and CD40L-mediated activation in HIV-infected subjects

T cell dysfunction in HIV-infected subjects could be the consequence of altered sensitivity of CD4+ or CD8+ T cells to various costimulatory signals. Therefore, we studied proliferation and cytokine production in highly purified CD8+ and CD4+ T cells from HIV-infected and HIV- subjects, induced by co-activation via cell-bound CD80, CD86 and CD40 or by allo-activation. Regardless of the nature of the first and the costimulatory signal, CD8+ T cells from patients proliferated consistently less than controls, while responses from CD4+ T cells were similar in patients and controls. This phenomenon was observed after ligation of CD28 combined with anti-CD3 or phorbol myristate acetate (PMA), but also after allogeneic stimulation and after activation by CD40 and anti-CD3. Anti-CD3 combined with CD80 or CD86 induced a mixed Th1/Th2-type cytokine profile in both CD4+ and CD8+ T cells from controls, whereas anti-CD3 plus CD40 induced only low levels of Th2-type cytokines and no interferon-gamma (IFN-gamma) in CD4+ T cells. Compared with controls, CD4+ T cells from patients produced slightly lower levels of IL-10 but equal amounts of IFN-gamma, IL-4 and IL-5, while CD8+ T cells from patients produced less of all cytokines tested. In conclusion, responses of purified CD4+ T cells from HIV+ subjects to various costimulatory pathways are relatively intact, whereas CD8+ T cells are hyporesponsive at the level of proliferation and cytokine production. A generalized intrinsic CD8+ T cell failure might contribute to viral and neoplastic complications of HIV infection.

Equal IgG antibody response to pneumococcal vaccination in all stages of human immunodeficiency virus disease

To evaluate the immunogenicity and safety of a 23-valent pneumococcal vaccine in human immunodeficiency virus (HIV)-seropositive patients, 80 men and 18 women received 1 dose of the vaccine (Pneumo 23; Pasteur Mérieux MSD, Brussels). The total IgG antibody response against all 23 Streptococcus pneumoniae capsular antigens was measured. Antibody levels were expressed in arbitrary units per microliter, referring to a standard curve. Geometric mean titers of the total IgG capsular antibodies on the day of vaccination and 30-45 days later were compared. The ratios of titers after and before vaccination in patients with > 500, 200-500, and < 200 CD4 lymphocytes/microL were 10, 10, and 12.6, respectively. Nonresponse (ratio < 4) occurred in 17% of patients and was unrelated to CD4 cell count. The vaccine was well tolerated; no serious side effects occurred. In 83% of the patients with HIV infection, the total antipneumococcal IgG level was higher after vaccination.

The interleukin-2 receptor subunit expression and function on peripheral blood lymphocytes from HIV-infected and control persons

The expression of interleukin-2 receptor (IL2R) was studied on circulating lymphocytes from HIV-infected (HIV+) and control subjects, using chain-specific monoclonal antibodies and indirect immunofluorescence flow cytometry. The IL2R alpha chain expression was decreased on CD4 and CD8 T cells from HIV+ persons compared to controls. Conversely, beta chain expression was enhanced on both T cell subsets from the patients. IL2R-subunit levels were similar on natural killer cells from patients and controls. To evaluate the function of IL2R, we investigated to what extent IL2 could induce CD69, an early activation marker of lymphocytes. A dose-dependent increase of CD69 expression was observed on T and NK cells from all subjects. The upregulation of CD69 was similar on CD4 T and NK cells from patients and controls, but was more pronounced on CD8 T cells from HIV+ compared to HIV- subjects. Based on inhibition studies, both the alpha and the beta chain contributed to the IL-2-induced CD69 expression on CD4 T cells, pointing to involvement of the high-affinity receptor. The early activation of CD8 T cells and NK cells was mainly dependent on the intermediate-affinity receptor. We conclude that significant changes in IL2R alpha and beta chain expression on circulating T cells occur after HIV infection, but that early activation through IL2 is preserved or enhanced, even in advanced stages.

Selective increase of activation antigens HLA-DR and CD38 on CD4+ CD45RO+ T lymphocytes during HIV-1 infection

Infection with HIV results in a progressive depletion of CD4+ T cells and leads to significant in vivo lymphocyte phenotype changes. In this regard, the expression of HLA-DR and CD38 on CD8+ T cells has been shown to increase dramatically with disease progression. We investigated the expression of both activation markers on CD4+ T cells in HIV-1-infected subjects at different clinical stages of infection and compared the in vivo activation of CD4+ T cells with parameters of viral activity and CD8+ T cell activation. Fresh peripheral venous blood was obtained from 54 HIV-infected subjects and from 28 uninfected healthy controls. Three-colour immunophenotyping of the CD4+ T cell subset showed that the proportion of CD4+ T cells expressing HLA-DR (10% in HIV-negative controls) or CD38 (62% in HIV-negative controls) was higher in asymptomatic (P < 0.05 for CD38) and symptomatic (P < 0.001 for HLA-DR and CD38) HIV-infected subjects than in controls, whereas the proportion of CD4+ T cells expressing CD45RO (54% in controls) remained relatively unchanged. Simultaneous expression of HLA-DR and CD38 on CD4+ T cells increased from 2.3% in controls to 11% (P < 0.001) in asymptomatic and 22% (P < 0.001) in symptomatic HIV-infected subjects. This relative increase of CD38 and HLA-DR expression occurred mainly on CD4+ T cells co-expressing CD45RO. Changes in expression of HLA-DR and CD38 on CD4+ T cells correlated with similar changes on CD8+ T lymphocytes, with the presence of HIV antigen in the circulation, and with the disease stage of HIV infection.

Evaluation of two staging systems for HIV infection for use in developing countries

OBJECTIVE

To evaluate the clinical axis of the World Health Organization (WHO) clinical staging system and the modified WHO staging system proposed by Montaner et al. using the lymphocyte strata > 1500, 1500-1000 and < 1000 cells x 10(6)/l.

DESIGN

Cross-sectional study.

PATIENTS

Four hundred and fifteen consecutive patients with HIV infection attending three HIV reference centres in Belgium.

METHODS

Absolute CD4 lymphocyte counts were compared between stages within the two staging systems.

RESULTS

Median CD4 lymphocyte counts decreased with increasing stage of disease in both staging systems. Differences in median CD4 lymphocyte counts between stages of each staging system were statistically significant (Kruskal-Wallis one-way analysis of variance, P < 0.001). The WHO clinical stage 1 and the modified WHO stage I had positive predictive values of 56 and 58%, respectively, for identifying patients with CD4 lymphocyte levels > 500 cells x 10(6)/l. The WHO clinical stage 4 and the modified WHO stage IV had positive predictive values of 79 and 80%, respectively, for identifying patients with CD4 lymphocyte levels < 200 cells x 10(6)/l.

CONCLUSIONS

The WHO clinical staging system or a modified version of this system using lymphocytes stratification may be a good alternative in developing countries to the CD4 lymphocyte count-based HIV staging system used in the developed world. Cohort studies in developing countries are needed to assess their prognostic value.

Immunological parameters during treatment with ditiocarb (Imuthiol)

OBJECTIVES

To examine the effect of ditiocarb (DTC) treatment on immunological parameters of HIV infection. Immunophenotyping included CD4+ T-cell counting and the analysis of activation markers on CD8+ T cells. Anti-CD3-induced proliferation and anti-CD3-mediated cytotoxicity were monitored as indexes of T-cell function. In addition to the clinical evolution, HIV antigen and anti-p24 levels were monitored during treatment.

DESIGN

In this double-blind, placebo-controlled study, 50 HIV-seropositive patients belonging to all clinical disease stages were randomized to treatment with DTC or placebo and followed for 4 months.

METHODS

Immunophenotyping on whole blood was performed by flow cytometry, using combinations of anti-CD8 with anti-CD4, anti-HLA-DR, anti-CD38, anti-CD45RO and anti-CD57. Patient lymphocytes were freshly assayed for cytolytic capacity against OKT3-coated targets. T-cell proliferation was measured after 3 days of OKT3-stimulation.

RESULTS

No effect was observed on CD4 and CD8+ T-cell counts or on CD8+ T-cell activation markers, except for a selective increase in HLA-DR expressing CD8 cells in the DTC-treated group. Decline in anti-CD3-induced T-cell proliferation and rise in anti-CD3-mediated T-cell cytotoxicity were observed in the DTC and placebo groups. No effect on HIV antigen and anti-p24 antibody titres was observed. The incidence of clinical complications was similar in each group.

CONCLUSION

No beneficial immunomodulatory effect of DTC was demonstrated.

The prevalence of hairy leukoplakia in HIV seropositive and HIV seronegative immunocompromised patients

The prevalence of hairy leukoplakia was determined among 176 symptomatic HIV seropositive patients seen at the outpatient department of the Institute of Tropical Medicine in Antwerp, Belgium. Moreover, systematic tongue biopsies were performed during postmortem examination of 21 patients with AIDS, 100 HIV seronegative immunocompromised patients with haematologic or other malignancies and 100 HIV seronegative non-immunocompromised patients who died at the University Hospital Antwerp. Hairy leukoplakia was observed in 52 (29.5%) of the outpatients, but only in one (5%) of the AIDS patients in the postmortem study (P = 0.03). An explanation for this difference may be that significantly more AIDS patients who died had received either acyclovir or ganciclovir during the 3 months prior to the postmortem examination than the HIV seropositive outpatients during the 3 months prior to examination. Hairy leukoplakia occurred more often in Caucasian homosexual men with HIV infection (38%) than among heterosexual Africans with HIV infection (17%) (P = 0.06). Hairy leukoplakia was observed in none of the HIV seronegative patients.

Subset markers of CD8(+) cells and their relation to enhanced cytotoxic T-cell activity during human immunodeficiency virus infection

Using fresh whole blood or isolated lymphocytes, the activity of in vivo generated cytotoxic T-lymphocytes (CTL) was measured as the OKT3-specific lysis of HL-60 targets, in a cross-sectional study of 53 HIV (+) patients. CTL activity in the entire HIV(+) group was two to three times higher than in HIV(-) controls, with WHO stage 3 (=pre-AIDS) patients showing the highest cytolytic function. The whole-blood CTL assay was validated and its practical and theoretical advantages are discussed. Within the CD8(+) cells, the number and proportion of the CD45RO(+) "memory" subset were significantly increased in HIV(+) subjects. The HLA-DR(+) subset rose most spectacularly in the asymptomatic stage of the infection, while the CD38(+) subset was the only one still significantly rising between the pre-AIDS and the AIDS stage. CTL activity was most closely correlated with T8 cells expressing the CD38 marker. In the context of CTL, CD38 thus seems to reflect activation rather than immaturity. Lymphocytes from HIV(+) subjects with a high OKT3-specific lytic capacity also destroyed normal lymphoblasts to a significant extent, pointing to their possible involvement in an autodestructive process. Our data thus suggest the importance of T8 cytolytic function and/or T8 subtyping in the immunopathogenesis and the prognosis of HIV infection.

Evidence for circulating activated cytotoxic T cells in HIV-infected subjects before the onset of opportunistic infections

The activity of both cytotoxic T lymphocyte (CTL) and natural killer (NK) cells were measured cross-sectionally in 43 subjects seropositive for HIV, in 27 HIV- blood donors and in 24 HIV- persons from the Outpatients Clinic for sexually transmitted diseases. CTL activity was evaluated using the HL-60 cells coated with OKT3 as the targets and freshly separated peripheral blood lymphocytes as the effectors. In 20 out of 43 HIV+ subjects, CTL activity was significantly enhanced in comparison to the HIV- subjects. This lytic activity correlated positively with the percentages of CD3+ HLA-DR+, of CD8+ CR3- and of CD57+ CD16- lymphocytes, and was greatly reduced after elimination of CD8+, of HLA-DR+ or of CD57+ cells. The median CTL activity seemed to increase from CDC group II to CDC group IV (Centers for Disease Control classification), but to return back to control levels in those patients with a history of opportunistic infections. NK function in HIV+ subjects was not significantly different from that in the blood donors. In seropositive patients, NK activity correlated positively with the percentages of both CD16+ CD57+ and of CD8+ CR3+ cells and was strongly diminished after elimination of CD16+ or of CD57+ cells. There was no significant change in NK function according to the clinical stage. The data show that circulating CD8+ HLA-DR+ CD57+ T cells in HIV+ subjects are activated cytotoxic T cells and point to progressive (over) activation of this T cell compartment until the onset of opportunistic infections.

Evaluation of two enzyme immunoassays for detection of human immunodeficiency virus antigen in African and European sera

The performance of two HIV antigen enzyme immunoassays (EIAs), the HTLV-III antigen EIA (Abbott) and the Innotest HIV antigen EIA (Innogenetics), was assessed using 276 HIV-1 antibody positive and 42 HIV antibody negative sera from European and African individuals. On the initial screening 16% (51/318) of the sera were reactive in the Abbott EIA and 21.4% (68/318) in the Innotest EIA. The Innotest detected significantly more confirmed HIV antigen positive sera (55/58, 94.6%) than the Abbott EIA (41/58, 70.7%). The presence of free detectable HIV antigen in African and European sera was strongly associated with the clinical classification CDC IV and with low p24 antibody levels.