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T Verstraeten

Publications and source records attributed to T Verstraeten.

At least 19 recordsLinked to original sources
PubMed2001

Enhancing vaccine safety surveillance: a capture-recapture analysis of intussusception after rotavirus vaccination.

The Vaccine Adverse Event Reporting System (VAERS) is the passive reporting system for postmarketing surveillance of vaccine safety in the United States. The proportion of cases of an adverse event after vaccination that are reported to VAERS (i.e., VAERS reporting completeness) is mostly unknown. Therefore, the risk of such an event cannot be derived from VAERS only. To study whether its reporting sensitivity and risks could be estimated, VAERS was linked to data from a case-control and a retrospective cohort study in a capture-recapture analysis of intussusception after rotavirus vaccination (RV). Cases of intussusception after RV were selected from the common time frame (December 1998 through June 1999) and the common geographic area (19 states) of the three sources. Matching occurred on birth date, gender, state, date of vaccination, and date of diagnosis. Thirty-five matches were identified among a total of 84 cases. The estimated VAERS reporting completeness was 47%. The relative risks of intussusception in the periods 3-7 and 8-14 days after RV (relative risk = 22.7 and 4.4, respectively) were comparable with those reported in the two studies. Linkage of VAERS to complimentary data sources may permit more timely postmarketing assessment of vaccine safety.

Adverse Drug Reaction Reporting Systems↗
PubMed2001

Multiple sclerosis.

Explore the source record for details and available documents.

Hepatitis B Vaccines↗
PubMed2000

Regression models for disease prevalence with diagnostic tests on pools of serum samples.

Whether the aim is to diagnose individuals or estimate prevalence, many epidemiological studies have demonstrated the successful use of tests on pooled sera. These tests detect whether at least one sample in the pool is positive. Although originally designed to reduce diagnostic costs, testing pools also lowers false positive and negative rates in low prevalence settings and yields more precise prevalence estimates. Current methods are aimed at estimating the average population risk from diagnostic tests on pools. In this article, we extend the original class of risk estimators to adjust for covariates recorded on individual pool members. Maximum likelihood theory provides a flexible estimation method that handles different covariate values in the pool, different pool sizes, and errors in test results. In special cases, software for generalized linear models can be used. Pool design has a strong impact on precision and cost efficiency, with covariate-homogeneous pools carrying the largest amount of information. We perform joint pool and sample size calculations using information from individual contributors to the pool and show that a good design can severely reduce cost and yet increase precision. The methods are illustrated using data from a Kenyan surveillance study of HIV. Compared to individual testing, age-homogeneous, optimal-sized pools of average size seven reduce cost to 44% of the original price with virtually no loss in precision.

Biometry↗
PubMed1999

Unusual cutaneous lesions in two patients with visceral leishmaniasis and HIV infection.

Two HIV infected patients with visceral leishmaniasis and unusual cutaneous lesions are described. The first patient developed linear brown macules containing Leishmania parasites on the fingers and palms of the hands. This patient never received highly active antiretroviral treatment and the visceral leishmaniasis could not be cured even with liposomal amphotericin. In the second patient, Leishmania parasites were present in a skin biopsy of a fibrous histiocytoma. After completing visceral leishmaniasis treatment, a discrete elevation of one of his tattoos was seen. A biopsy specimen of this tattoo revealed Leishmania amastigotes. In this patient the visceral leishmaniasis was finally cured with meglumine antimoniate, followed by pentacarinat isothianate as maintenance therapy in conjunction with highly active antiretroviral treatment.

AIDS-Related Opportunistic Infections↗
PubMed1998

Recurrence of blackwater fever: triggering of relapses by different antimalarials.

Five cases of blackwater fever (BWF) are described, all of whom had a history of recent quinine therapy. In two cases a second haemolytic crisis was induced by halofantrine, in one case also a third. Increasing frequency of this syndrome with its dramatic clinical presentation is to be expected as imported P. falciparum infection, parasite resistance to chloroquine and the use of quinine and other related antimalarials become more frequent.

Adult↗
PubMed1998

Pooling sera to reduce the cost of HIV surveillance: a feasibility study in a rural Kenyan district.

Seroprevalence studies are crucial in HIV control programs but too expensive at district level. We evaluated the applicability of pooling sera and how it can reduce cost and affect accuracy at district level. 740 samples collected from antenatal clinic attendants for a sentinel survey in a rural Kenyan district were screened individually and in pools of 10. The seroprevalence when measured individually was 7.30%, while the calculated seroprevalence from pooled testing was 7.49%. Pooling was practicable and reduced costs by 62% for a marginal loss of accuracy. It is a useful tool in increasing the affordability of surveillance at district level. A pool size of 8 would have resulted in optimal cost reduction at minimal loss of accuracy.

Blood Specimen Collection↗
PubMed1997

Evaluation of two rapid hepatitis B surface antigen detection tests for screening in a blood bank.

The sensitivity and specificity of two rapid, low cost latex agglutination HBsAg detection tests were compared to a EIA HBsAg detection test using serum samples from 371 pregnant women in Kajiado, a rural Kenyan district. The sensitivity of the latex agglutination tests when compared to the EIA was 70.6% and 61.8%, while specificity was 92.0% and 85.2% respectively for the same tests. In view of their low sensitivity these rapid tests are not suitable for screening blood in district hospitals.

Blood Banks↗
PubMed1996

Rhodococcus equi infection in 3 AIDS patients.

Three cases of AIDS complicated by Rhodococcus equi infection are reported. At least one of the patients acquired his Rhodococcus infection in Africa. Despite the fact that the R. equi strains were susceptible to tetracycline, erythromycin, amikacin, co-trimoxazole, rifampicin and vancomycin, these antibiotics were clinically not successful. A clinical improvement was observed in only one patient during teicoplanin and imipenem-cilastatin treatment. Multicentre clinical trials are needed to determine the optimal treatment of R. equi infections in AIDS patients.

AIDS-Related Opportunistic Infections↗
PubMed1996

Neurological manifestations of acute posterior multifocal placoid pigment epitheliopathy.

BACKGROUND: Acute posterior multifocal placoid pigment epitheliopathy (APMPPE) is a chorioretinal disease that causes acute visual symptoms with characteristic fundus findings. Although this entity has been associated with a variety of neurological complications, it has received little attention in the neurological literature. We wanted to emphasize the spectrum of neurological involvement, in particular the occurrence and management of strokes in patients with APMPPE. CASE DESCRIPTIONS: We report three patients with APMPPE and neurological disease. All three presented with marked visual disturbances and headaches. One patient developed recurrent strokes involving different vascular territories of the brain and required immunosuppressive treatment for presumed cerebral vasculitis. The other two patients had cerebrospinal fluid pleocytosis and persistent headaches but recovered spontaneously. The review of the literature demonstrates a particular pattern of neurological complications in a subgroup of patients with APMPPE. CONCLUSIONS: APMPPE should be considered among the causes of stroke and aseptic meningitis in young adults. The diagnosis is critically dependent on a thorough ophthalmologic examination. Severe neurological complications are difficult to predict at the onset of the ophthalmologic disease. The patients should be monitored closely. If investigations suggest cerebral vasculitis, immunosuppressive treatment may be helpful to prevent recurrences.

Acute Disease↗
PubMed1995

Acute Schistosomiasis in Travelers Returning From Mali.

Acute schistosomiasis or "Katayama syndrome" occurs in previously uninfected persons 3-6 weeks after exposure to cercaria-infested water.1,2 Many outbreaks among tourists have been reported.3-11 Such outbreaks occur because tourists are bathing or swimming in waters thought by tourist organizations to be bilharzial free. Imported schistosomiasis acquired in the Dogon country in Mali, West Africa, was first demonstrated in 1989 in three Spanish travelers;3 in 1991, an outbreak was described among Dutch travelers.7 In 1993, we investigated a similar outbreak among European and American travelers returning from the same area.

Journal Article↗
PubMed1995

Lens-sparing vitrectomy with perfluorocarbon liquid for the primary treatment of giant retinal tears.

PURPOSE: To evaluate the surgical success of vitrectomy without initial lensectomy in the primary treatment of retinal detachment associated with giant tears without proliferative vitreoretinopathy. METHODS: Thirty-four consecutive phakic eyes with idiopathic giant retinal tears underwent vitrectomy, injection of perfluorocarbon liquid, endolaser, and gas tamponade. Encircling scleral buckling was performed in 14 of 34 patients. Preoperative visual acuity ranged from 20/25 to hand motions. Giant tear size ranged from 90 degrees to 330 degrees. Follow-up ranged from 10 to 64 months. RESULTS: Anatomic retinal re-attachment was achieved intraoperatively in all eyes. The re-operation rate was 14% for eyes that underwent scleral buckling with the initial vitrectomy and 45% in eyes without primary scleral buckling. In 59% of eyes with cataract formation, 32% underwent cataract surgery with or without intraocular lens implantation. Best-corrected final visual acuity ranged from 20/15 to 20/400. CONCLUSION: Most phakic eyes with giant retinal tear not associated with proliferative vitreoretinopathy can be re-attached successfully with initial preservation of the lens.

Adolescent↗
PubMed1995

Histoplasma capsulatum infection in three AIDS patients living in Africa.

Three AIDS patients are reported, 2 European and 1 African. All 3 developed Histoplasma capsulatum infection while living in Africa. Two developed a pulmonary infiltrate, and 2 had skin lesions. One patient was successfully treated with itraconazole, 400 mg daily; in a second patient, itraconazole was partially successful; the third patient was lost to follow-up before adequate treatment could be started. Histoplasma infection is probably an often undiagnosed complication in African AIDS patients.

AIDS-Related Opportunistic Infections↗
PubMed1994

Prolonged monitoring for detection of symptomatic arrhythmias after slow pathway ablation in AV-nodal tachycardia.

To study the incidence of symptoms and recurrences of AV-nodal re-entrant tachycardia (AVNT) after treatment with radio-frequency ablation of the slow pathway, event recording with transtelephonic transmission was performed for at least 3 weeks in 19 patients out of a series of 25. Follow-up with an implanted antitachycardia device was possible in two other patients, making the total number under continued surveillance 21/25. The period of monitoring was prolonged as complaints remained or became present after 1 month in eight patients. During a mean follow-up of 10 months, late recurrence of AVNT was observed in this way in 4/25 patients; they were submitted to a second procedure. Symptoms were present in many others and were explained by the recordings. Sinus tachycardia was recorded in three patients, intermittent AV-block of the first degree in another, and frequent atrial or ventricular premature beats in six patients. These minor arrhythmias tended to decrease over time. A coexistent atrial tachycardia was redetected in two patients. Thus, event recording is useful to distinguish recurrence of AVNT, sinus tachycardia, other types of supraventricular tachycardia, and atrial or ventricular premature beats, which all may be a reason of complaints during the first weeks after ablation. It provided a feeling of safety for symptomatic patients who often suffered from anxiety before the ablation.

Adult↗
PubMed1994

Protection of health care workers against bloodborne infections in emergency departments.

Health care workers in emergency departments are at particular high risk for acquiring occupational bloodborne infections. Needle stick injuries are the main hazard. Systematic HIV testing of patients admitted to emergency department is not a cost beneficial way to protect health care workers from acquiring such infections. Prevention strategies should be based on the adherence to universal precautions, hepatitis B vaccination, the utilization of safer devices and the training/education of health care workers.

Belgium↗
PubMed1994

The "automatic mode switch" function in successive generations of minute ventilation sensing dual chamber rate responsive pacemakers.

Automatic mode switch (AMS) from DDDR to VVIR pacing is a new algorithm, in response to paroxysmal atrial tachyarrhythmias. With the 5603 Programmer, the AMS in the Meta DDDR 1250 and 1250H (Telectronics Pacings Systems, Inc.) operates when VA is shorter than the adaptable PVARP. With the 9600 Programmer, an atrial protection interval can be defined after the PVARP. The latest generation, Meta DDDR 1254, initiates AMS when 5 or 11 heart cycles are > 150, 175, or 200 beats/min. From 1990 to 1993, 61 patients, mean age 61 years, received a Meta DDDR: in 24 a 1250, in 12 a 1250H and in the remaining 25 a 1254 model. Indication for pacing was heart block in 39, sick sinus syndrome in 15, the combination in 6, and hypertrophic obstructive cardiomyopathy in 1. Paroxysmal atrial tachyarrhythmias were present in 43. All patients had routine pacemaker surveillance, including 52 Holter recordings. In 32 patients, periods of atrial tachyarrhythmias were observed, with proper AMS to VVIR, except during short periods of 2:1 block for atrial flutter in 4. In two others, undersensing of the atrial arrhythmia disturbed correct AMS. With the 1250 and 1250H model, AMS was observed on several occasions during sinus rate accelerations in ten patients. This was never seen with the 1254 devices. Final programmation was VVIR in 2 (chronic atrial fibrillation), AAI in 1 (fracture of the ventricular lead), VDDR in 1 (atrial pacing during atrial fibrillation), DDD in 5, and DDDR in 53, 48 of whom had AMS programmed on.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1992

Effects of vitamin A on retinal pigment epithelial cells in vitro.

Human retinal pigment epithelial (RPE) cell monolayers were used in an in vitro wound-healing experiment. Wound closure were studied over time in the presence of various concentrations of all-trans retinol (vitamin A). It was found that 5-20 micrograms/ml (17.5-70 mumol/l) of vitamin A significantly inhibited wound closure by inhibiting cell migration and proliferation. In a collagen gel-contraction model, similar doses of vitamin A partially inhibited cell contractility. Cellular morphology, as assessed by phase-contrast microscopy, changed from a regular polygonal shape to an elongated stellate shape. Indirect immunofluorescence patterns of fibronectin, actin, tubulin, and vimentin were altered after exposure to vitamin A. All these effects were reversible after removal of the drug from the medium. Modulation of RPE growth and cell-mediated contraction may be useful in the treatment of ocular proliferative diseases.

Cell Count↗
PubMed1990

Evaluation of a viscoelastic solution of hydroxypropyl methylcellulose as a potential vitreous substitute.

Hydroxypropyl methylcellulose (HPMC), an inert polymer that forms a viscoelastic solution in aqueous media, is useful for anterior segment surgery. A 2.2% solution of HPMC (MW 86,000 daltons) of 6,000 centistokes viscosity was evaluated as a vitreous substitute in rabbit eyes. Four days after perfluoropropane gas compression of the vitreous, the gas was exchanged with 0.5 ml HPMC. The aqueous was removed 1 and 2 weeks postinjection and at sacrifice, the vitreous was removed at sacrifice. HPMC concentrations in aqueous humor were: 0 hr, 0%; 48 hr, 0.002%; 1 week, 0.004%; 2 weeks, 0.001%; 4 weeks, 0%. HPMC concentrations in vitreous were: 48 hr, 93% of amount injected; 2 weeks, 88%; 4 weeks, 78%; 10 weeks, 0%. Hyaluronidase injected in the vitreous enhanced HPMC elimination. The effect of HPMC also was assayed on a cultured retinal pigment epithelial monolayer. Compared with controls, HPMC-treated cells maintained normal morphology at 5 days, and 2, 3, and 4 weeks as observed by light microscopy. Because of rapid intraocular decrease in viscosity, HPMC is not a good long-term vitreous replacement to support retinal tears. However, HPMC might be useful short-term to avoid postoperative hypotony, and to remove intraocular silicone oil and peel retinal membranes.

Animals↗