Snoek, E.M. van der

Photodynamic therapy with systemic meta-tetrahydroxyphenylchlorin in the treatment of anal intraepithelial neoplasia, grade 3 (Article)

2012-10-01T00:00:00Z

Background and Objective Anal cancer and preneoplastic anal lesions (anal intraepithelial neoplasia, AIN) rising especially in men having sex with men (MSM). There are no widely accepted treatment standards for AIN. Photodynamic therapy (PDT) using the systemic sensitizer meta-tetrahydroxyphenylchlorin (mTHPC) has the potential to treat the anal area even when the exact borders of the preneoplastic anal lesion cannot easily be visualized. Study Design/Materials and Methods In this prospective intervention study, 15 HIV-positive MSM with AIN 3 were treated in 25 PDT-sessions using mTHPC intravenously administered at drug doses of 0.075-0.15 mg ml-1and illumination at 48 hours. The illumination was performed using a custom made applicator using either red light (652 nm) to a measured intended fluence of 10 and 20 J cm-2and green light (532 nm) to a measured intended fluence of 105, 210, and 340 J cm-2. Red and green illuminations were performed at a (green) equivalent fluence rate of 105 mW cm-2. Results Initial complete response was seen in 7/25 (28%) of treatments and another 4/25 (16%) initial partial responses. After an average 8 months, recurrences were detected in 7/11 (64%) of sessions that initially showed response. A total 4/25 (16%) showed persistent complete response 6-15 months after green light illumination. Red light illuminations caused more significant side effects combined with no persistent complete response. Reported side effects were intense pain, bloody and purulent rectal discharge, and anal stricture formation, in one patient. Conclusion The results show that the use of systemic mTHPC is partially effective for the treatment of AIN 3. Lasers Surg.

A dedicated applicator for light delivery and monitoring of PDT of intra-anal intraepithelial neoplasia (Article)

2010-03-01T00:00:00Z

The objective of this study was to develop an applicator for delivery of light and monitoring of photodynamic therapy (PDT) in the anal cavity for treatment of anal intraepithelial neoplasia grade III (AIN III), which can progress to invasive anal cancer. Forty-eight hours before treatment, patients participating in the study were injected with 0.03 (n = 2) or 0.075 (n = 2) mg kg-1m-THPC. For light delivery and monitoring of PDT, an applicator based on standard anoscopy equipment was developed which facilitates, in addition to a light treatment fiber, fiber optic probes to monitor blood saturation, blood volume, fluorescence and fluence (rate) at two different locations in situ. Patients were given a light dose of 10-17 J cm-2at a fluence rate of 45-50 mW cm-2based on in situ measured light treatment parameters. We demonstrate that the applicator does not influence the fluence rate profile of the light treatment fiber. Furthermore this study shows the possibility of monitoring blood saturation, blood volume, fluorescence and fluence (rate) during therapeutic illumination without changing the light treatment protocol.

Photodynamic therapy with topical metatetrahydroxychlorin (Fosgel) is ineffective for the treatment of anal intraepithelial neoplasia, grade III (Article)

2009-09-01T00:00:00Z

A review of photodynamic therapy in cutaneous leishmaniasis (Article)

2008-08-01T00:00:00Z

We present a review of six clinical studies investigating the use of photodynamic therapy (PDT) using porphyrin precursors for the treatment of Old World cutaneous leishmaniasis (CL). Thirty-nine patients with a total of 77 lesions received PDT using a range of treatment schedules following topical application of aminolevulinic acid (ALA) or methyl-aminolevulinate (MAL). The tissue response to PDT is accompanied by a mild burning sensation, erythema and reversible hypo- and hyperpigmentation. Few mechanistic studies have addressed the principles underlying the use of PDT for CL. All six reviewed papers suggest that PDT with porphyrin precursors is relatively effective in treating CL. Data are still limited, and PDT cannot at this point be recommended in routine clinical practice. The mechanism of action of this promising therapeutic modality needs to investigated further and additional controlled trials need to be performed.

Authors' reply [2] (Article)

2008-02-01T00:00:00Z

The use of serological titres of IgA and IgG in (early) discrimination between rectal infection with non-lymphogranuloma venereum and lymphogranuloma venereum serovars of Chlamydia trochomotis (Article)

2007-07-01T00:00:00Z

Objectives: To investigate whether serological titres of species-specific IgA and IgG antibodies in patients with rectal chlamydial infection could discriminate between infection with serovar L2 lymphogranuloma venereum (LGV) and infection with non-LGV serovars. Methods: A total of 39 male patients with chlamydial infection of the rectum were tested for titres of IgA and IgG antibodies within 14 days after detection of the infection and 6 and 12 months after adequate treatment. Data were collected regarding demographics, sexual orientation, HIV serostatus, history of chlamydial infection, concomitant sexually transmitted infection (STI) or HIV infection, hepatitis C virus antibodies and new STIs during follow-up. Results: Between May 2003 and November 2005, 24 men with confirmed L2 proctitis and 15 men with non-LGV rectal chlamydial infection were recruited. In multivariable analyses, both high titre of IgA within 14 days after detection of the infection and older age of the individual were found significantly associated with L2 proctitis (p<0.001 and p = 0.001, respectively). A total sum score of seven times IgA titre and individual's age ≥50 years resulted in an overall sensitivity of 92% and specificity of 100%. This total sum score was highly accurate for detection of LGV proctitis, with an area under the curve in a receiver operating characteristic curve of 0.989. Conclusions: An increased IgA antibody response and the age of the infected individual are of possible diagnostic value for (early) detection of LGV proctitis.

HIV incidence and HIV testing behavior in men who have sex with men: Using three incidence sources, the Netherlands, 1984-2005 (Article)

2007-02-01T00:00:00Z

BACKGROUND: In The Netherlands, the western part, including Rotterdam and Amsterdam harbors the majority of the known HIV-infected population, of whom men who have sex with men (MSM) comprise the largest transmission category. Given a general rise in sexually transmitted infections (STI) and risky sexual behavior, we examine the HIV incidence among MSM in the Netherlands with data from three different sources. METHODS: To describe the HIV epidemic among MSM we use: a prospective cohort study in Rotterdam (ROHOCO: 1998-2003, n = 265) and another in Amsterdam (ACS: 1984-2005, n = 1498]) plus an anonymous HIV surveillance study (Amsterdam STI clinic: 1991-2004, n = 3733) in which HIV-positive MSM were tested with a less-sensitive HIV assay. We evaluated calendar trends in HIV incidence, also focusing on age effects. RESULTS: Since the start of the HIV epidemic in the early 1980s, incidence has declined strongly in the ACS. In recent years, an increase was noted among older MSM attending the Amsterdam STI clinic (P = 0.0334). In both cohort studies, HIV incidence was lower and recent time-trends were not statistically significant. Among recently infected men at the STI clinic, only 40% accepted named HIV testing at their STI consultation. CONCLUSIONS: Data suggest that among MSM in the Netherlands, the HIV incidence is between one and four infections per 100 person-years. The epidemic expands among older STI clinic attendees. Prevention should be developed specifically for older men, along with a more efficient HIV testing approach such as routine HIV testing of MSM when they are screened for STI.

STDs and HIV infection in men who have sex with men: Rotterdam cohort study (Doctoral Thesis)

2004-11-04T00:00:00Z

A general introduction is presented in chapter 1. The Rotterdam cohort study (ROHOCO) took place from February 1999 to January 2002 at the sexually transmitted diseases (STDs) clinic of the department of Dermatology and Venereology of the Erasmus MC, University Medical Centre Rotterdam, The Netherlands. The aim of our study was to monitor the cumulative incidence of STDs and HIV infection in men who have sex with men (MSM) and to longitudinally investigate the associated behavioural changes during the three-year cohort study. Apart from behavioural aspects, highly active antiretroviral therapy (HAART) and post-exposure prophylaxis (PEP) treatment beliefs as well as determinants of health, knowledge of transmission of HIV and STDs, perceived severity of different STDs and HIV infection and perceived susceptibility to certain STDs and HIV infection were compiled in order to examine associations with the cumulative incidence of STDs and HIV infection.