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D van Soolingen

Publications and source records attributed to D van Soolingen.

At least 37 records · Page 2Linked to original sources
PubMed2002

Effect of screening of immigrants on tuberculosis transmission.

SETTING: In The Netherlands all immigrants from highly endemic countries undergo obligatory entry screening by X-ray, followed by voluntary half-yearly screening for 2 years. OBJECTIVE: To estimate the contribution of screening of immigrants to reductions in tuberculosis transmission. DESIGN: All bacteriologically confirmed tuberculosis patients diagnosed between 1994 and 1999 with mycobacterial isolates exhibiting identical DNA fingerprints were assigned to clusters. Clusters were assumed to be a consequence of recent transmission and to have had the first patient as their source case. Among patients with pulmonary tuberculosis from highly endemic countries, the characteristics of source patients were compared with those of non-clustered patients. RESULTS: Of the 1438 selected patients, 187 (13%) were the first in a cluster, 386 (27%) were in a cluster but were not the first case, and 865 (60%) were not clustered. Independent risk factors for being the first in a cluster were young age, nationality, early year of diagnosis, longer duration of treatment and no concurrent extra-pulmonary tuberculosis. In univariate analysis, passively detected patients and patients with a long duration of stay in The Netherlands were more likely to be the first in a cluster than patients detected by screening and recent arrivals, respectively. However, these variables were strongly associated. CONCLUSION: Screening of immigrants can reduce tuberculosis transmission. This effect is in part due to confounding by duration of stay.

Adolescent↗
PubMed2002

A low cost, home-made, reverse-line blot hybridisation assay for rapid detection of rifampicin resistance in Mycobacterium tuberculosis.

SETTING: Cetrangolo Hospital, Vicente Lopez, Argentina, 1995-1999. OBJECTIVE: To describe a home-made reverse-line blot hybridisation assay for the detection of rifampicin resistance-associated mutations in the rpoB gene of Mycobacterium tuberculosis, and to evaluate the usefulness of this rifampicin oligonucleotide, or 'RIFO' assay, to predict rifampicin resistance. DESIGN: A total of 135 M. tuberculosis isolates from the Cetrangolo Hospital were tested using the RIFO assay, the proportion method and the Mycobacterial Growth Indicator Tube (MGIT 960). In addition, 120 drug-susceptible isolates from the Netherlands were included. RESULTS: The results obtained with the proportion method and the MGIT 960 system were in full agreement. In the RIFO assay, 90 of the 97 rifampicin-resistant isolates were correctly identified (sensitivity 92.8%, positive predictive value 100%). All of the drug-susceptible isolates were correctly predicted by the RIFO assay. CONCLUSIONS: With this home-made molecular test, rifampicin resistance in M. tuberculosis can be predicted in colonies isolated in culture in only 1 day, and can therefore shorten the laboratory turn around time for rifampicin susceptibility testing by weeks. In principle the test can also be applied directly to Zichl-Neelsen slides and clinical material, as has been demonstrated for another reverse-line blot-based assay for M. tuberculosis, spoligotyping.

Antibiotics, Antitubercular↗
PubMed2001

Transmission of Mycobacterium tuberculosis depending on the age and sex of source cases.

This study estimated to what extent tuberculosis transmission in the Netherlands depends on the age and sex of source cases. DNA fingerprints of Mycobacterium tuberculosis isolates were matched to patient information in the Netherlands Tuberculosis Register for 1993-1998. Clusters were defined as groups of patients with pulmonary tuberculosis whose isolates had identical DNA fingerprints. Source cases were assigned by using two models. The first-case model assumed that the first diagnosed case was the source case. The incidence rate model estimated source case probabilities from the incidence rates of potential source cases and the time of diagnosis. DNA fingerprints of 6,102 isolates were matched to patient information on 5,080 (83%) cases, 3,479 of whom had pulmonary disease. According to both models, the number of infectious cases generated per source case was lower for female than for male source cases and decreased with increasing age of the source case. The authors concluded that transmission of tuberculosis is associated with the age and sex of source cases as well as the age of secondary cases. Increased transmission among immigrant groups in the Netherlands is largely attributable to the relatively young age of immigrant source cases.

Adult↗
PubMed2001

Epidemiological evidence of the spread of a Mycobacterium tuberculosis strain of the Beijing genotype on Gran Canaria Island.

Molecular epidemiological studies suggest that particular Mycobacterium tuberculosis strains have an enhanced capacity to spread within a community. One strain, the Beijing genotype, has been associated with outbreaks in a number of communities throughout the world. IS6110 restriction fragment length polymorphism (RFLP) analysis was performed on M. tuberculosis isolates from 566 of the 721 patients (78.5%) diagnosed with tuberculosis (TB) on Gran Canaria Island from 1993 to 1996, as well as 35% of isolates from 1991-1992 (85 strains). RFLP identification of the family of strains of the Beijing genotype was confirmed by spoligotyping. Medical records of all patients were reviewed and epidemiological links were identified. Of 566 M. tuberculosis isolates from 1993 to 1996 with RFLP available, 72% belonged to clusters. The largest contained 75 cases and was caused by a strain of the Beijing genotype that was introduced to the island in 1993. It was found in 10 patients in 1993 (5.5%), 12 in 1994 (8.1%), 18 in 1995 (16.4%), and 35 in 1996 (27.1%). Epidemiological linkage was confirmed for 68% of cases. This study has demonstrated rapid dissemination of this strain of the Beijing genotype. This genotype might play an important role in the future of the worldwide tuberculosis epidemic.

Adolescent↗
PubMed2001

Divergent effect of bacillus Calmette-Guérin (BCG) vaccination on Mycobacterium tuberculosis infection in highly related macaque species: implications for primate models in tuberculosis vaccine research.

Despite the widespread use of bacillus Calmette-Guérin vaccination, Mycobacterium tuberculosis infection remains globally the leading cause of death from a single infectious disease. The complicated and often protracted dynamics of infection and disease make clinical trials to test new tuberculosis vaccines extremely complex. Preclinical selection of only the most promising candidates is therefore essential. Because macaque monkeys develop a disease very similar to humans, they have potential to provide important information in addition to small animal models. To assess the relative merits of rhesus and cynomolgus monkeys as screens for tuberculosis vaccines, we compared the efficacy of bacillus Calmette-Guérin vaccination and the course of infection in both species. Unvaccinated rhesus and cynomolgus monkeys both developed progressive disease with high levels of C-reactive protein, M. tuberculosis-specific IgG, and extensive pathology including cavitation and caseous necrosis. Bacillus Calmette-Guérin vaccination protected cynomolgus almost completely toward the development of pathology, reflected in a striking 2-log reduction in viable bacteria in the lungs compared with nonvaccinated animals. Rhesus, on the other hand, were not protected efficiently by the bacillus Calmette-Guérin. The vaccinated animals developed substantial pathology and had negligible reductions of colony-forming units in the lungs. Comparative studies in these closely related species are likely to provide insight into mechanisms involved in protection against tuberculosis.

Animals↗
PubMed2001

BCG immunotherapy: be cautious of granulomas. Disseminated BCG infection and mycotic aneurysm as late complications of intravesical BCG instillations.

We describe a 65-year-old man with a granulomatous hepatitis and a progressive mycotic aneurysm of the abdominal aorta. One year before he received intravesical bacillus Calmette--Guérin (BCG) for carcinoma of the bladder without any complaints. Only post-mortem investigations could confirm that he suffered from a systemic BCG infection. Literature is reviewed for this rare complication.

Aged↗
PubMed2001

Repeatedly negative tuberculin skin tests followed by active tuberculosis in an immunocompetent individual.

We describe a woman who was repeatedly tuberculin (PPD) skin test negative after exposure to smear-positive tuberculosis (TB), but developed active TB with a positive skin test 7 years later. Molecular epidemiologic evidence is presented that the infection was contracted 7 years previously from the original source case. PPD skin testing is subject to many technical and biological variables and this report underscores that this tool can fail to detect latent TB infection in some cases. The causes of false-negative and false-positive PPD skin test results are reviewed.

Acute Disease↗
PubMed2001

Nosocomial transmission of tuberculosis to a nurse demonstrated by means of spoligotyping of a formalin-fixed bronchial biopsy.

BACKGROUND: Tuberculosis was diagnosed in a student nurse. The source of infection was unknown and no positive culture was available. METHODS: The diagnosis of tuberculous bronchitis was established on the grounds of a positive Mantoux test, the pathology of a bronchial biopsy and the results of a CT scan of the thorax. Spoligotyping of, for example, formalin-fixed tissue makes it possible to establish the diagnosis in a later phase after all. RESULTS: Cultures for Mycobacterium tuberculosis were not performed for the student nurse and Ziehl-Neelsen staining of the formalin-fixed bronchial biopsy was negative. The final tuberculosis diagnosis was confirmed by a PCR fingerprint technique, i.e., spoligotyping of a formalin-fixed biopsy specimen. By means of contact investigation and identification of the strain via spoligotyping, comparison of the spoligo patterns made it possible to treat both the patient and those infected by this person correctly. CONCLUSIONS: When there is a pronounced suspicion of tuberculosis and a microbiological culture is not available, it is recommended that supplementary spoligotyping of clinical specimens be carried out. The purpose is to confirm the diagnosis, trace the presumed source case and indirectly to provide information on the drug susceptibility of the relevant M. tuberculosis strain.

Biopsy↗
PubMed2001

Molecular epidemiological study on transmission of tuberculosis in a hospital for mentally handicapped patients in Havana, Cuba.

The IS 6110 restriction fragment length polymorphism (RFLP) analysis of Mycobacterium tuberculosis isolates has revolutionized the description of the epidemiology of tuberculosis. This technique has been used to confirm suspected cases of transmission in several institutional settings. In this study, we analysed by conventional and molecular epidemiological methods the unexpectedly high number of tuberculosis cases which occurred among 14 mentally handicapped patients and a healthcare worker in Havana's Psychiatric Hospital in the period from 1995 to 1998. Twelve M. tuberculosis isolates of the respective patients showed the same DNA fingerprint, consisting of nine bands. Three other different IS 6110 RFLP patterns with 10, eight, and 10 bands were observed. The results of RFLP analysis and of an additional epidemiological investigation allowed the identification of the probable source of this chain of transmission in the healthcare facility. This would not have been possible without the aid of DNA fingerprinting. Delays in diagnosis of the source patient and of the secondary cases, a tardy and deficient tuberculin skin test and the difficulties of management of mentally handicapped patients probably contributed to spread the M. tuberculosis strain in Havana's Psychiatric Hospital.

Adult↗
PubMed2001

Automated high-throughput genotyping for study of global epidemiology of Mycobacterium tuberculosis based on mycobacterial interspersed repetitive units.

Large-scale genotyping of Mycobacterium tuberculosis is especially challenging, as the current typing methods are labor-intensive and the results are difficult to compare among laboratories. Here, automated typing based on variable-number tandem repeats (VNTRs) of genetic elements named mycobacterial interspersed repetitive units (MIRUs) in 12 mammalian minisatellite-like loci of M. tuberculosis is presented. This system combines analysis of multiplex PCRs on a fluorescence-based DNA analyzer with computerized automation of the genotyping. Analysis of a blinded reference set of 90 strains from 38 countries (K. Kremer et al., J. Clin. Microbiol. 37:2607-2618, 1999) demonstrated that it is 100% reproducible, sensitive, and specific for M. tuberculosis complex isolates, a performance that has not been achieved by any other typing method tested in the same conditions. MIRU-VNTRs can be used for analysis of the global genetic diversity of M. tuberculosis complex strains at different levels of evolutionary divergence. To fully exploit the portability of this typing system, a website was set up for the analysis of M. tuberculosis MIRU-VNTR genotypes via the Internet. This opens the way for global epidemiological surveillance of tuberculosis and should lead to novel insights into the evolutionary and population genetics of this major pathogen.

Automation↗
PubMed2001

The susceptibility of Mycobacterium tuberculosis to isoniazid and the Arg-->Leu mutation at codon 463 of katG are not associated.

A mutation (CCG-->CTG [Arg-->Leu]) in codon 463 of katG (catalase peroxidase) of Mycobacterium tuberculosis has been found in isoniazid (INH)-resistant strains. A PCR restriction endonuclease analysis to detect this mutation was applied to 395 M. tuberculosis isolates from patients in The Netherlands. The proportion of isolates with a detectable mutation was 32% (32 out of 100) and 29% (85 out of 295) among INH-susceptible isolates and INH-resistant or -intermediate isolates, respectively. Sequencing of five INH-susceptible isolates with such mutations showed that all five had the Arg463Leu mutation. We conclude that the Arg463Leu mutation of katG of M. tuberculosis is not a reliable indicator of INH resistance.

Antitubercular Agents↗
PubMed2001

Transmission of tuberculosis in Havana, Cuba: a molecular epidemiological study by IS6110 restriction fragment length polymorphism typing.

The combination of molecular and conventional epidemiological methods has improved the knowledge about the transmission of tuberculosis in urban populations. To examine transmission of tuberculosis in Havana, Cuba, with DNA fingerprinting, we studied 51 out of 92 Mycobacterium tuberculosis strains isolated from tuberculosis patients who resided in Havana and whose infection was culture-confirmed in the period from September 1997 to March 1998. Isolates from 28 patients (55%) had unique IS6110 restriction fragment length polymorphism (RFLP) patterns, while isolates from 23 others (45%) had identical patterns and belonged to 7 clusters. Three clusters consisting of six, five and two cases were each related to small outbreaks that occurred in a closed setting. Three other clustered cases were linked to a large outbreak that occurred in another institution. Younger patients were more correlated to clustering than older ones. The finding that 45% of the isolates had clustered RFLP patterns suggests that recent transmission is a key factor in the tuberculosis cases in Havana. The IS6110 RFLP typing made it possible to define the occurrence of outbreaks in two closed institutions.

Adult↗
PubMed2001

The effect of age and study duration on the relationship between 'clustering' of DNA fingerprint patterns and the proportion of tuberculosis disease attributable to recent transmission.

Though it is recognized that the extent of 'clustering' of isolates from tuberculosis cases in a given population is related to the amount of disease attributable to recent transmission, the relationship between the two statistics is poorly understood. Given age-dependent risks of disease and the fact that a long study (e.g. spanning several years) is more likely to identify transmission-linked cases than a shorter study, both measures, and thus the relationship between them, probably depend strongly on the ages of the cases ascertained and study duration. The contribution of these factors is explored in this paper using an age-structured model which describes the introduction and transmission of M. tuberculosis strains with different DNA fingerprint patterns in The Netherlands during this century, assuming that the number of individuals contacted by each case varies between cases and that DNA fingerprint patterns change over time through random mutations, as observed in several studies. Model predictions of clustering in different age groups and over different time periods between 1993 and 1997 compare well against those observed. According to the model, the proportion of young cases with onset in a given time period who were 'clustered' underestimated the proportion of disease attributable to recent transmission in this age group (by up to 25% in males); for older individuals, clustering overestimated this proportion. These under- and overestimates decreased and increased respectively as the time period over which the cases were ascertained increased. These results have important implications for the interpretation of estimates of the proportion of disease attributable to recent transmission, based on 'clustering' statistics, as are being derived from studies of the molecular epidemiology of tuberculosis in many populations.

Adolescent↗
PubMed2001

Family outbreaks of tuberculosis in South Moravia, a low incidence area of the Czech Republic.

OBJECTIVES: To identify suspected family outbreaks of tuberculosis in South Moravia, an area with the lowest notification rates in the Czech Republic. METHOD: The insertion sequence IS6110-based RFLP analysis of Mycobacterium tuberculosis was applied in isolates collected from 17 indigenous excretors giving the same family name and/or domicile. The fingerprints were matched with a database of 184 RFLP profiles of Czech M. tuberculosis isolates originating from remote localities. RESULTS: The RFLP analysis revealed uniform fingerprints in each of six indigenous outbreaks consisting of two to six family members or relatives. In three of them no matching case has been found in the Czech fingerprint database. The remaining three clusters showed identical patterns with RFLP profiles of 13 Czech M. tuberculosis strains originating from remote areas: five were from patients living in the immediate vicinity and eight were from distant regions. CONCLUSION: Different clustered genotypes of M. tuberculosis were identified in epidemiologically linked family outbreaks of tuberculosis, half of them indigenous and half matching fingerprints of strains from remote areas. It seems that family outbreaks may contribute to the continued occurrence of tuberculosis in South Moravia, which reports the lowest notification values in the Czech Republic.

Adolescent↗
PubMed2000

Mutations at amino acid position 315 of the katG gene are associated with high-level resistance to isoniazid, other drug resistance, and successful transmission of Mycobacterium tuberculosis in the Netherlands.

The prevalence of mutations at amino acid (aa) position 315 in the katG gene of isoniazid (INH)-resistant Mycobacterium tuberculosis isolates in The Netherlands and the mutation's association with the level of INH resistance, multidrug resistance, and transmission were determined. Of 4288 M. tuberculosis isolates with available laboratory results, 295 (7%) exhibited INH resistance. Of 148 aa 315 mutants, 89% had MICs of 5-10 microg/mL, whereas 75% of the other 130 INH-resistant strains had MICs of 0.5-1 microg/mL. Of the aa 315 mutants, 33% exhibited monodrug resistance, compared with 69% of other INH-resistant strains (P<.0001). Multidrug resistance was found among 14% of the aa 315 mutants and 7% of the other INH-resistant strains (P>.05). The probability of being in an IS6110 DNA restriction fragment length polymorphism cluster was similar for aa 315 mutants and INH-susceptible strains, but the probability was reduced in other INH-resistant strains. Thus, aa 315 mutants lead to secondary cases of tuberculosis as often as INH-susceptible strains do.

Antitubercular Agents↗