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J Veen

Publications and source records attributed to J Veen.

At least 19 recordsLinked to original sources
PubMed1998

Analysis of tuberculosis transmission between nationalities in the Netherlands in the period 1993-1995 using DNA fingerprinting.

Immigration from high prevalence areas may contribute to an increased risk of tuberculosis in Europe. This study aimed at quantifying transmission of tuberculosis between and within nationalities among residents of the Netherlands. DNA "fingerprints," on the basis of restriction fragment length polymorphism using marker IS6110, were made of all Mycobacterium tuberculosis isolates in the Netherlands from January 1993 through June 1995. Clusters were defined as groups of patients that had isolates with identical fingerprints. It was assumed that the probability of a patient being the source of a cluster was proportional to the incidence rate of potential sources times the probability that a potential source would give rise to a cluster. The transmission index was defined as the average number of secondary cases of infectious tuberculosis caused directly or indirectly through recent transmission by a single potential source case and was used to estimate the effective reproductive rate associated with recent transmission, ReFAST. Among a total of 623 Dutch tuberculosis cases, 17% (95% confidence interval 9-25%) of cases were attributable to recent transmission from a non-Dutch source. The transmission index varied strongly by nationality, and was highest among the Surinamese (1.3), Moroccan (0.8), and Turkish (0.8) populations; ReFAST was 0.26. Aggregation of tuberculosis cases of given nationalities within clusters was most pronounced among recent immigrants from Somalia and (ex-)Yugoslavia. The authors conclude that differences in transmission between subpopulations can be quantified and may be used to evaluate and direct tuberculosis control.

Adolescent↗
PubMed1998

Treatment of pulmonary tuberculosis.

Recently the duration of treatment for pulmonary tuberculosis in The Netherlands was shortened from nine to six months. A six months regimen containing isoniazid (H), rifampicin (R) and pyrazinamid (Z) daily for two months, followed by H and R daily for another four months (2HRZ/2HR) has been proven effective for the treatment of pulmonary tuberculosis, provided the cause is a fully susceptible strain of M. tuberculosis. Worldwide there is an increase in drug-resistant tuberculosis. Since at the start of treatment susceptibility tests often are not available, a fourth drug must be added in the intensive phase. Ethambutol is the drug preferred. This means that one always starts with 4 drugs unless the patient is a contact of an index-case with proven susceptibility and one is sure that he will be compliant or the patient is infected in the past before 1940, he received never tuberculostatic drugs and one is sure that there is no exogenous reinfection. If the patient has been treated previously and anti-tuberculosis drug resistance is likely, treatment regimens should contain at least two drugs with which he has not been treated before, while a fifth drug routinely must be added in the intensive phase. Amikacin is preferred, since there is no cross-resistance to streptomycin. Consensus on the duration of treatment for extra-pulmonary tuberculosis has not yet been reached, but basically the principles for treatment are the same. This is also true for HIV infected tuberculosis patients. In some serious clinical situations (meningitis, miliary, spine tb) duration of treatment still is 9-12 months. Early involvement of the public health nurse of the municipal health department (GGD) is necessary to ensure patient compliance and treatment supervision.

AIDS-Related Opportunistic Infections↗
PubMed1998

Reversible increase in tight junction permeability to macromolecules in rat ileal mucosa in vitro by sodium caprate, a constituent of milk fat.

Intestinal tight junction function is thought to be of importance in the pathogenesis of various diseases. The regulation of uptake of macromolecules via the tight junctions is largely unknown. Effects of luminal sodium caprate (10 mM), a dairy product constituent, and cytochalasin B (30 microM), were studied in rat ileum in vitro in Ussing chambers. Both agents caused a reversible fall in potential difference and increased [51Cr]EDTA permeability. In addition, sodium caprate induced increased permeability to polysucrose (15,000 daltons) and opening of the tight junctions as visualized by transmission electron microscopy. Dose-response patterns suggested mainly dose-dependent differences between the agents. Confocal laser scanning microscopy suggested paracellular permeation of polysucrose. Luminal sodium caprate, a food constituent, can increase tight junction permeability, allowing passage of macromolecules, without affecting epithelial viability. Increased permeability to medium-sized molecules does not necessarily coincide with increased paracellular uptake of protein-sized molecules.

Animals↗
PubMed1998

Mortality among tuberculosis patients in The Netherlands in the period 1993-1995.

This study aimed to estimate excess mortality among tuberculosis patients in The Netherlands and identify risk factors for tuberculosis-associated mortality. The national tuberculosis register provided data on patients diagnosed in the period 1993-1995. Excess mortality in tuberculosis cases, according to age and sex, was determined by comparison with national mortality rates. Risk factors were identified and adjustment for confounders was carried out using Cox's proportional hazard analysis. Of 4,340 patients alive at diagnosis, 258 died within 1 yr while on treatment. The Kaplan-Meier survival probability after 1 yr was 93%. Tuberculosis patients had a standardized mortality ratio of 8.3. Independent risk factors for mortality were: gender; age; presence of a malignancy or human immunodeficiency virus (HIV) infection; addiction to alcohol or drugs; localization of tuberculosis; and the type of medical officer having made the diagnosis. Of all deaths, 83% occurred in two risk groups comprising 21% of tuberculosis patients: those aged > or =65 yrs and those having HIV infection or a malignancy. Tuberculosis patients in The Netherlands are at a considerably increased risk of death. However, the prognosis is very good for those aged less than 65 yrs and without human immunodeficiency virus infection or a malignancy.

Adult↗
PubMed1998

Standardized tuberculosis treatment outcome monitoring in Europe. Recommendations of a Working Group of the World Health Organization (WHO) and the European Region of the International Union Against Tuberculosis and Lung Disease (IUATLD) for uniform reporting by cohort analysis of treatment outcome in tuberculosis patients.

Consensus-based recommendations have been developed by a Working Group of the World Health Organisation (WHO) and the International Union Against Tuberculosis and Lung Disease (IUATLD) on uniform reporting of tuberculosis (TB) treatment outcome data in countries in Europe. The main purpose of treatment monitoring is to find out how many of the potential infectious TB patients notified were declared cured at the end of treatment. Following the uniform case definitions as defined in 1996, emphasis is placed on cohort analysis of definite cases of pulmonary TB. The Working Group recommends using a minimal set of six mutually exclusive categories of treatment outcome: cure, treatment completed, failure, death, treatment interrupted, and transfer out. More detailed subsets may be chosen. Treatment outcome is expressed as a percentage of the total number of cases notified. Analysis should be separate for new and retreatment cases. Treatment outcome data have to be collected at the local level and passed on to regional and national authorities on an ongoing basis. Evaluation of treatment results becomes, preferably, an inbuilt component of national monitoring of programme performance. Because of the long duration of treatment, it is recommended that analysis is carried out in the first quarter of the calendar year that follows a full year after the last patient was enrolled. Feedback is essential. Treatment outcome results should become an inseparable part of the annual report on tuberculosis.

Cohort Studies↗
PubMed1998

Nationwide surveillance of drug-resistant tuberculosis in The Netherlands: rates, risk factors and treatment outcome.

SETTING: The Netherlands, 1993 and 1994. OBJECTIVE: To determine 1) rates of drug resistance in relation to nationality and country of birth, 2) risk factors for drug resistance, 3) treatment outcome of drug-resistant cases, and 4) rates of primary and acquired drug resistance. DESIGN: Retrospective study of all cases notified with bacillary tuberculosis in The Netherlands in 1993 and 1994. RESULTS: Drug resistance to one or more drugs was reported in 268 (14.6%) of all 1836 cases, of whom 203 (76%) were foreign born. In Dutch patients rates of isoniazid (H) (2.9%) and streptomycin resistance (3.6%) were lower than in foreign patients (8.6% and 10.6% respectively, P < 0.001). Multidrug (H and rifampicin [R]) resistance was reported in 0.5% of Dutch-born and 1.4% of foreign cases (P = 0.055). Rates of acquired resistance to H (11.4%) and HR (5.7%) were higher than rates of primary resistance to these drugs (5.2% and 0.7% respectively, P < 0.05), but the number of retreatment cases was low (6.8% of all cases). Drug resistance was associated with immigration but not with drug use, homelessness or human immunodeficiency virus (HIV) co-infection. One fifth (20%) of drug-resistant cases was diagnosed by active case finding. Treatment outcome in sensitive and resistant cases was compared. CONCLUSION: These findings suggest that drug resistance is imported, but it is unclear to what extent drug resistance among foreigners has been transmitted or created in The Netherlands. Drug resistance data should be monitored in Dutch and foreign patients separately.

Antitubercular Agents↗
PubMed1998

Origin and management of primary and acquired drug-resistant tuberculosis in The Netherlands: the truth behind the rates.

SETTING: The Netherlands, May 1994 to May 1996. OBJECTIVE: 1) To estimate to what extent drug-resistant tuberculosis was acquired or recently transmitted in The Netherlands, 2) to assess the relevance of drug resistance data as routinely collected, and 3) to describe case management. DESIGN: Prospective descriptive study. Patients diagnosed with drug-resistant tuberculosis were interviewed. Information on patient management and contact tracing was collected. IS6110 restriction fragment length polymorphism (RFLP) patterns of all strains were compared with those of the National RFLP library and clusters were analyzed. RESULTS: In total 193 cases were included in the study. Acquired drug resistance (ADR) was rare. Dutch ADR patients reported receiving treatment a long time previously (mean age 58, mean treatment interval 23 years). Most foreign ADR patients had been treated recently in their country of origin. Of 151 primary drug-resistant (PDR) cases, 129 (85%) were foreign-born, of whom few (8%-19%) had been infected in The Netherlands. Few Dutch PDR cases had been infected recently (mean age 49 years). Rifampicin resistance was more frequently observed in foreign ADR cases than in foreign PDR cases (28% vs 5%; P < 0.001). One third of cases had not been treated according to treatment guidelines. CONCLUSION: Only a small proportion of drug-resistant cases resulted from recent infection or treatment in The Netherlands. General rates of ADR and PDR do not reflect current Dutch programme performance. For programme monitoring, ADR/PDR rates and their trends must be reported and evaluated in Dutch and foreign patients separately.

Adult↗
PubMed1997

Use of DNA fingerprinting in international source case finding during a large outbreak of tuberculosis in The Netherlands.

SETTING: Tuberculosis outbreak in a low prevalence country. OBJECTIVE: Description of an international source tracing process in which restriction fragment length polymorphism (RFLP) analysis played an essential role. DESIGN: In 1993 a large scale source tracing process was initiated in Harlingen, a harbour town in the north of The Netherlands, after a child with tuberculous meningitis was reported for which no source could be identified. Traditional contact tracing followed the detection of sources of infection. RFLP was used to map the tuberculosis transmission and identify the source case. RESULTS: The investigation extended from the north to several places in the west of The Netherlands. In total 6519 persons were screened; there were 276 infections, among which 49 cases of active tuberculosis were identified. RFLP analysis of Mycobacterium tuberculosis isolates from all 28 culture positive patients showed the 'Harlingen' type DNA fingerprint. After 5 months source tracing led to the identification of the source case in the United Kingdom. Up to June 1996 altogether 37 patients (The Netherlands 28; the UK 7; Surinam 1; Morocco 1) were found to have isolates with the Harlingen type DNA pattern. Despite a thorough evaluation, in 5 of the 37 patients no relation to the source case or the outbreak in Harlingen could be established. CONCLUSION: RFLP typing proved a very useful instrument in guiding the process of international source tracing and contact investigation.

Adolescent↗
PubMed1996

[Transmission of sensitive and resistant strains of Mycobacterium tuberculosis in The Netherlands, 1993-1995, studied by means of DNA fingerprinting].

OBJECTIVE: Determination of the contribution of recent transmission of both sensitive and drug-resistant Mycobacterium tuberculosis strains to the number of tuberculosis cases in the Netherlands. DESIGN: Descriptive study. SETTING: National Institute for Public Health and Environment, Bilthoven, the Netherlands. METHODS: Since 1993 all isolates of M. tuberculosis in the Netherlands are sent to the national reference laboratory for surveillance purposes. The strains with IS6110 DNA fingerprint, isolated from January 1993 to July 1995, were analysed for clustering of DNA patterns (clustering of identical DNA patterns was assumed to represent recent transmission of tuberculosis). A transmission index was calculated from the ratio of the number recently infected tuberculosis patients and the number of source patients. RESULTS: Among 2,217 M. tuberculosis isolates, 1,313 unique DNA fingerprints were observed, while 264 DNA patterns occurred more than once. 904 (41%) DNA fingerprints were part of a cluster of identical fingerprints. The mean cluster size was 3.42. The 232 resistant strains showed significantly less clustering (33% versus 42%, p < 0.02) and a smaller transmission index (0.27 versus 0.42, p < 0.02) compared with sensitive strains. CONCLUSION: Recent transmission contributes to the magnitude of the tuberculosis problem in the Netherlands. The epidemiological situation would, however, lead to gradual elimination of the disease were it not for introduction of tuberculosis from other countries. Transmission of resistant strains is relatively limited. Micro-epidemics caused by resistant M. tuberculosis strains were not observed.

DNA Fingerprinting↗
PubMed1996

[Border-crossing source tracing in tuberculosis via DNA fingerprint technique].

OBJECTIVE: Description of the value of modern DNA analysis ('restriction fragment length polymorphism'; RFLP) as a method for mapping tuberculosis transmission. DESIGN: Descriptive. SETTING: Social Health Service Noord-Friesland, the Netherlands. METHOD: A large-scale tuberculosis investigation was conducted in Harlingen in 1993 when a 2,5 year old patient with tuberculous meningitis was reported. Source tracing and contact tracing extended from Harlingen to the west of the Netherlands and even abroad. Modern DNA analysis (RFLP) was used to map the tuberculosis transmission. RESULTS: A total of 6519 persons were screened and 276 infected people were identified, of whom 49 were suffering from active tuberculosis. RFLP analysis showed in 27 of them a 'Harlingen' type Mycobacterium tuberculosis DNA pattern identical to that of the index patient. The source patient was finally traced in England. By the end of 1994 3 more patients were found with the same DNA pattern; their relation with the source patient and the outbreak of tbc remained unrevealed. CONCLUSION: The Harlingen outbreak was extensive and characterized by time-consuming source tracing. Modern DNA analysis proved to be a very useful instrument in identifying the source case.

Adult↗
PubMed1996

[Shortening of therapy duration in patients with pulmonary tuberculosis from 9 to 6 months only justifiable on the basis of published data].

OBJECTIVE: To determine if in the Netherlands, just like in other countries, the treatment of pulmonary tuberculosis with adequately sensitive tubercle bacilli may be shortened from 9 to 6 months. DESIGN: Literature study. SETTING: Municipal Health Service, Nijmegen, the Netherlands. METHOD: The relevant literature was analysed, using the percentage of recurrences as the criterion. The study was restricted to patients with pulmonary tuberculosis in whom the diagnosis had been confirmed bacteriologically and in whom a human, normally sensitive tubercle bacillus had been isolated. The treatment schedule had to include at least isoniazid, rifampicin and pyrazinamide. There were no studies with treatment of 9 months' duration. The studies with 6 months' treatment were selected on the basis of the predetermined criteria from among articles included in Medline in 1980-1991. RESULTS: The treatment schedules of 6 months' duration (n = 44) from 25 articles were suitable for analysis. Treatment for 6 months' resulted in a proportion of recurrences of tuberculosis of 2.4% (95%-confidence interval: 2.0-2.8), with follow-up periods of 12 to 94 months after discontinuation of the treatment. Addition of streptomycin or ethambutol during the initial phase, self-medication or controlled treatment, daily or intermittent treatment made no difference as regards the ultimate results. No comparison with the proportion of recurrences of 1% (0.2-2.9) after 9 month's treatment without pyranizamide was possible. A recent calculation of the number of Dutch nationals with recurrent tuberculosis resulted in a proportion of recurrences of 2.5 (1.8-3.2). The guideline adopted was that mentioned by the American Thoracic Society, a proportion of recurrences of < 5%. CONCLUSION: On the basis of the known percentages of recurrence, it could be decided in the Netherlands as well to shorten the duration of treatment from 9 to 6 months.

Antitubercular Agents↗
PubMed1996

[Drug resistance in Mycobacterium tuberculosis in The Netherlands].

OBJECTIVE: To determine magnitude, trend and specific features of the resistance problem. DESIGN: Descriptive. SETTING: Royal Netherlands Tuberculosis Association, The Hague, the Netherlands. METHODS: The data of the National Institute of Public Health and Environmental Protection concerning the prevalence of drug-resistant tuberculosis during the period 1990-1994 were analysed. Also, features of patients with and without drug resistance were compared (Dutch National Tuberculosis Register: cohort 1993). RESULTS: Isoniazid and streptomycin resistance were each observed in approximately 6% of susceptibility tests, showing no clear trend over the study period. Rifampicin resistance increased from 0% to 1.5% in 1994. In the 1993 patient cohort, 809 cases were analysed, showing resistant organisms in 103 (13%). The resistance group included 84 (82%) foreigners versus 387 (55%) among the 'sensitives' (p < 0.001). The percentages of (known) HIV infections were equal in both groups (5-6%). The percentage of isoniazid-resistance varied from 1.8% in Dutch patients to 7.8% in foreign patients. Recent immigrants and refugees waiting for official status were important risk groups for resistance (p < 0.005). Foreign tuberculosis patients defaulted more often from treatment than Dutch patients (p < 0.001). CONCLUSION: Drug-resistant tuberculosis in the Netherlands is mainly due to import of resistant strains. Transmission and further development of resistance within the country must be prevented.

Antibiotics, Antitubercular↗
PubMed1995

Control of drug-resistant tuberculosis.

Drug-resistant tuberculosis is a global problem, but the necessity and quality of intervention should be assessed by country since the causes of drug resistance, and thus the appropriate intervention strategies, may vary considerably between countries. An analysis of the development and spread of drug-resistant tuberculosis is presented and the respective roles of import of the disease and of HIV are discussed. A definition of inadequate treatment and a systematic approach to the quantitative and qualitative aspects of the drug resistance problem is proposed. The 'treatment delivery process' (TDP) is introduced as a diagnostic tool to analyse the causes of secondary (or acquired) resistance in a specific area. Intervention strategies should be based on the evaluation of this TDP. Intervention strategies and general aspects of their implementation are discussed.

Antitubercular Agents↗