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F Portaels

Publications and source records attributed to F Portaels.

At least 91 records · Page 5Linked to original sources
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

Evaluation of the Gen-Probe amplified Mycobacterium tuberculosis direct test for the routine diagnosis of pulmonary tuberculosis.

A total of 624 respiratory specimens from 543 patients (418 Belgian, 110 Rwandan, and 15 Colombian patients) were tested for the presence of Mycobacterium tuberculosis by the Mycobacterium Tuberculosis Direct Test (MTDT, Gen-Probe). Compared to culture, the MTDT on 497 samples of sputum or broncho-alveolar lavage from Belgium had a sensitivity, specificity and positive and negative predictive value of 86.4%, 96.0%, 50.0% and 99.3% respectively. The pooled results for Rwanda (112 specimens) and Colombia (15 specimens) were 97.8%, 65.7%, 88.2%, 92% respectively. After resolution of discrepant results by taking into account the clinical data, the results for the Belgian patients were 86.9%, 96.2%, 52.6%, 99.3% respectively, and for the Rwandan-Colombian patients 98.1%, 100%, 100% and 92% respectively. Results could be improved by testing more than one specimen from each patient and the inclusion of an internal control to detect inhibitors of the reaction. Culture remains necessary for drug susceptibility tests and the isolation and identification of non-tuberculous mycobacteria.

Belgium↗
PubMed1996

[Tuberculosis: multidrug-resistance in Belgium in 1992 and 1993].

The "Belgian TB Multidrug Resistance Working Group" determined in collaboration with 28 laboratories carrying out antibiograms for mycobacteria, the prevalence and incidence of multidrug resistance in Belgium in 1992-1993. During this period, respectively 14 (1.1%) and 17 (1.3%) cases of multidrug resistance (i.e. resistance to at least isoniazid and rifampicin, according to the W.H.O. definition), were detected by these laboratories. Since 9 new cases of multidrug resistance were detected in 1992 and 10 in 1993, the incidence of multidrug resistance in Belgium can be estimated at 0.1 per 100.000 inhabitants. Among these 19 new cases, 2 are confirmed as primary resistance cases.

Adolescent↗
PubMed1996

Mycobacteriosis caused by Mycobacterium genavense in birds kept in a zoo: 11-year survey.

We report on a disease in 27 birds (1 bird belonging to the order Coraciiformes, 3 to Piciformes, 4 to Galliformes, 7 to Psittaciformes, and 12 to Passeriformes) caused by fastidious mycobacteria. All birds were caged at the Antwerp Zoo and died suddenly between 1983 and 1994. Seventeen birds had no previous signs of disease, and 10 birds showed emaciation. Gross necropsy findings were generally nonspecific, but all the birds were smear positive for acid-fast bacilli (AFB). Histopathologic evaluation performed on 14 birds revealed predominantly intracellular AFB. Extracellular AFB were more abundant in advanced lesions, especially in necrotic areas. In the intestine the mucosal area was generally heavily infiltrated, suggesting an intestinal origin of the infection. There was extensive invasion of the lungs in most birds. In 11 birds sparse growth was obtained after at least 6 months of incubation on Löwenstein-Jensen medium or on Ogawa medium supplemented with mycobactin. Subculture was unsuccessful in all instances. The 16S rRNA gene sequence of the cultured organisms or tissues from seven birds revealed the characteristic signature sequence for Mycobacterium genavense. Direct bird-to-bird transmission in the zoo was unlikely, and the pathogenicity of M. genavense in birds seems to be limited. The source of M. genavense in nature and the epidemiology of the disease in birds remain obscure. As suspected for human cases of M. genavense infection, an oral route of infection has been suggested, and contaminated local water distribution systems may have been the source of the infection. Our study confirms that infections caused by M. genavense should be suspected in birds (especially in Passeriformes and Psittaciformes orders) that die suddenly without previous symptoms and that have AFB in tissues that are difficult to grow on conventional media.

Animals↗
PubMed1996

Variability in 3' end of 16S rRNA sequence of Mycobacterium ulcerans is related to geographic origin of isolates.

Mycobacterium ulcerans causes extensive ulcers (Buruli ulcers) in the skin of humans. Analysis of the 3'-terminal region of the 16S rRNA gene sequence of 17 strains of M. ulcerans from Africa, the Americas, and Australia revealed three subgroups corresponding to the continent of origin, and some variable phenotypic characteristics. This sequence is useful for the rapid detection of M. ulcerans and discriminates M. marinum and M. shinshuense from M. ulcerans.

Africa↗
PubMed1996

Mycobacterium ulcerans infection (Buruli ulcer): first reported patients in Togo.

Mycobacterium ulcerans infection (Buruli ulcer) is the third most common mycobacterial infection of immunocompetent humans, and is an emerging disease in West Africa. We describe the first two reported patients with Buruli ulcer in Togo, establishing a geographical continuum of the disease in all countries bordering the Gulf of Guinea. The aetiological agent was identified by molecular biological analysis of biopsy material. We speculate that changing environmental factors related to human habitation may influence rates of incidence of Buruli ulcer.

Child↗
PubMed1995

Pulmonary tuberculosis in HIV-infected patients in Zaire. A controlled trial of treatment for either 6 or 12 months.

BACKGROUND: We studied the efficacy of a short-course regimen of chemotherapy for pulmonary tuberculosis in Kinshasa, Zaire. We also assessed whether, among patients with human immunodeficiency virus (HIV) infection, treatment should be extended from 6 to 12 months. METHODS: HIV-seropositive and HIV-seronegative outpatients with pulmonary tuberculosis were treated with rifampin, isoniazid, pyrazinamide, and ethambutol daily for two months, followed by rifampin plus isoniazid twice weekly for four months. The HIV-positive patients who had no evidence of tuberculosis were then randomly assigned to receive either rifampin plus isoniazid or placebo twice weekly for a further six months. We also followed a comparison group of HIV-seronegative patients who received no further treatment for tuberculosis after six months. RESULTS: After six months, 260 of 335 HIV-seropositive and 186 of 188 HIV-seronegative participants could be evaluated, and their rates of treatment failure were similar: 3.8 and 2.7 percent, respectively. At 24 months, the HIV-seropositive patients who received extended treatment had a relapse rate of 1.9 percent, as compared with 9 percent among the HIV-seropositive patients who received placebo for the second 6 months (P < 0.01). Extended treatment did not improve survival, however. Among the HIV-seronegative patients, 5.3 percent relapsed. CONCLUSIONS: Among HIV-seropositive patients with pulmonary tuberculosis, extending treatment from 6 to 12 months reduces the rate of relapse but does not improve survival. The six-month program of partly intermittent antituberculous treatment may be an acceptable alternative when resources are limited.

AIDS-Related Opportunistic Infections↗
PubMed1995

Rapid detection of rifampicin resistance in sputum and biopsy specimens from tuberculosis patients by PCR and line probe assay.

SETTING: Multidrug resistant Mycobacterium tuberculosis strains are threatening TB control in the world. Rapid diagnosis of resistance is essential for adequate treatment and optimal control of the disease. OBJECTIVE: Evaluation of a new technique (Line Probe Assay, LiPA) for easy and rapid detection of Rifampicin resistance (RMPR) of M. tuberculosis. DESIGN: After amplification of the region of the RNA polymerase, involved in RMPR, the amplified product is hybridized with a set of 10 oligonucleotides immobilized onto a membrane strip. From the pattern obtained the presence or absence of RMPR M. tuberculosis can be assessed. 67 clinical samples positive in culture for M. tuberculosis were analyzed with LiPA and results were compared with classical susceptibility testing. RESULTS: In vitro drug sensitivity testing identified 46 rifampicin sensitive and 21 resistant strains. In 65 of the 67 specimens LiPA results matched classical testing. In two RMPR cases LiPA showed a sensitive pattern. CONCLUSION: In contrast to culture and sensitivity testing, where results take on average 6 weeks, LiPA testing is an easy and rapid (< 48 h) method of detecting RMPR M. tuberculosis in clinical samples. Results correlated in 97% of the samples. In the two RMPR samples with a sensitive LiPA pattern another mechanism of resistance is suspected.

Amino Acid Sequence↗
PubMed1995

Drug resistant tuberculosis in sub-Saharan Africa: an estimation of incidence and cost for the year 2000.

SETTING: Rwanda. OBJECTIVES: To evaluate the tuberculosis (TB) drug resistance in Rwanda on smear positive sputa, collected prospectively at the start of the National TB programme, before the start of any treatment or retreatment. To adapt the scenarios of Schulzer et al (1992) to the data from Rwanda, in order to obtain an estimation of the number of drug resistant and multi-drug resistant (MDR) TB cases expected by the year 2000. DESIGN: A total of 298 specimens (236 randomly selected new cases and 62 retreated cases), collected between January 1991 and June 1993, were sent to Belgium in 1% cetylpyridinium chloride. Drug resistance was determined using the proportion method. RESULTS: MDR, i.e. resistance to at least rifampicin (R) and isoniazid (H), was observed in 3 (1.3%) out of 236 new cases and in 4 (6.5%) out of 62 treated cases. For new cases, single drug resistance to H, R and ethambutol (E) was 3%, 0.4% respectively; for treated cases it was 14.5%, 1.6% and 6.5 respectively. Based on the estimate of the size of the TB problem in sub-Saharan Africa by the year of 2000 (Schulzer), we calculated that the region should expect between 15,543 and 223, 417 cases of MDR, all forms combined (between 2.3 and 32.7 per 100,000 inhabitants), by the end of the century. CONCLUSION: The results from Rwanda during the period studied do not appear dramatic. However, for some other developing countries, they may just represent the tip of the iceberg. Rapid recognition of resistance to the major antituberculosis agents is essential for control of TB. Integration of an MDR increase factor into the TB budget would not dramatically increase the total TB budget. Our data urgently point the the need for drug resistance surveys, followed by continuous drug resistance monitoring in high TB prevalence areas.

Africa South of the Sahara↗
PubMed1995

Isolation of Mycobacterium malmoense from the environment in Zaire.

Two strains of mycobacteria isolated from water and soil in Zaire were identified as Mycobacterium malmoense by biochemical tests and lipid analysis. Apart from the previously reported fatty acids characteristic of this species, both strains, as well as 5 clinical isolates of M. malmoense, contained 2,4-dimethyl-docosanoic acid. One of the environmental strains, with a glycolipid pattern II, additionally contained 2-methyltetradecanoic acid. The results confirm that M. malmoense may be subdivided in 2 sub-groups according to its lipid patterns. They also show that M. malmoense can be isolated from the environment which may be the source of the infection.

Democratic Republic of the Congo↗
PubMed1995

Analysis of the population structure of Mycobacterium tuberculosis in Ethiopia, Tunisia, and The Netherlands: usefulness of DNA typing for global tuberculosis epidemiology.

The genetic heterogeneity among Mycobacterium tuberculosis isolates from 501 patients in Ethiopia, Tunisia, and the Netherlands was compared by analysis of DNA polymorphism driven by insertion element IS6110. The percentage of isolates displaying two or more identical patterns differed greatly in the three countries: It was highest among Tunisian isolates and lowest in Dutch isolates. In contrast to isolates from Dutch subjects infected with M. tuberculosis, the majority of strains from Ethiopia and Tunisia were from a few families of genetically highly related strains. Furthermore, little overlap was observed among isolates from the three countries, indicating strict isolation of the bacterial reservoirs in the countries. A few strains from the Netherlands matched strains from Ethiopia and Tunisia. Those strains were invariably isolated from refugees, immigrants, or persons who visited Ethiopia or Tunisia.

Cluster Analysis↗
PubMed1995

Detection and identification of mycobacteria by DNA amplification and oligonucleotide-specific capture plate hybridization.

We have developed an easy and rapid detection and identification system for the diagnosis of mycobacterial diseases. The system is based on selective amplification by PCR of mycobacteria with primers based on the genes coding for 16S rRNA. During PCR, a label (digoxigenin-11-dUTP) is incorporated with biotinylated species-specific oligonucleotides (oligonucleotide-specific capture plate hybridization [OSCPH]. One oligonucleotide specific for the genus Mycobacterium and seven species-specific (Mycobacterium tuberculosis, M. avium, M. intracellulare, M. scrofulaceum, M. xenopi, M. genavense, and M. chelonae) oligonucleotides were designed as capturing probes. After specific hybridization, an enzyme immunoassay reveals the specifically bound complexes and thus permits identification of the mycobacterium. A total of 70 mycobacterial strains were tested. For 69 strains, results concordant with conventional identification were obtained. One M. chelonae strain was negative with the M. chelonae probe and was later reidentified as M. fortuitum. Moreover, for 15 clinical samples suspected of harboring nontuberculous mycobacteria, OSCPH was able to confirm all culture results and could identify one M. genavense infection for which standard culture results were negative. PCR-OSCPH is easily applicable and much faster than culture. It could become a valuable alternative approach for the diagnosis of mycobacterial infections.

Base Sequence↗
PubMed1995

Predominance of a single genotype of Mycobacterium tuberculosis in countries of east Asia.

Analysis of the population structure of Mycobacterium tuberculosis strains from the People's Republic of China showed that the vast majority belong to a genetically closely related group. These strains shared the majority of their IS6110 DNA-containing restriction fragments, and also, the DNA polymorphism associated with other repetitive DNA elements, like the polymorphic GC-rich sequence and the direct repeat, was very limited. Because the majority of these strains originated from the province of Beijing, we designated this grouping the "Beijing family" of M. tuberculosis strains. Strains of this family were also found to dominate in neighboring countries such as Mongolia, South Korea, and Thailand, whereas a low prevalence of such strains was observed in countries on other continents. These data indicate that strains of the Beijing family recently expanded from a single ancestor which had a selective advantage. It is speculated that long-term Mycobacterium bovis BCG vaccination may be one of the selective forces implicated in the successful spread of the Beijing genotype.

China↗
PubMed1995

Species-specific Mycobacterium genavense DNA in intestinal tissues of individuals not infected with human immunodeficiency virus.

Mycobacterium genavense species-specific DNA was detected in intestinal tissues from two of nine individuals not infected with human immunodeficiency virus. This newly described microorganism is well documented as a causative agent of disseminated infections in AIDS patients. Our results suggest that it may colonize the guts of individuals not infected with human immunodeficiency virus.

Base Sequence↗
PubMed1995

[Analysis of restriction fragment length polymorphism (RFLP) in epidemiology of tuberculosis].

The purpose of this study was to determine the polymorphism of insertion segment 6110 (IS6110) in strains of Mycobacterium tuberculosis isolated from Colombian patients as well as the current status of resistance to antituberculosis drugs in the department of Quindío, Colombia. To this end, a prospective study was performed with a consecutive sample of 59 patients who sought care at local health centers and hospitals in rural and urban areas of Quindío from March to July 1993. The patients in the sample had symptomatic pulmonary tuberculosis confirmed by bacteriologic inspection of sputum, with and without a history of treatment, and were participants in the Tuberculosis Control Program of the Sectional Health Institute of Quindío in Armenia, Colombia. Sputum cultures and drug sensitivity tests were done. Later, restriction fragment length polymorphisms (RFLP) of IS6110 were analyzed in accordance with the protocols of van Soolingen et al. (1992). Cases were classified by treatment history, applying the criteria of WHO (1991). The results showed 44 cultures positive for M. tuberculosis and one positive for M. africanum. Primary drug resistance was found in 4 of 42 cultures, or 9.5% (CI 95%: 0.6 to 18); 4.8% were resistant to isoniazid (INH) and 4.8% to isoniazid and streptomycin (INH-SM). Acquired resistance was found in two of three cultures, or 66% (to isoniazid, rifampicin, and streptomycin [INH-RM-SM] and to isoniazid, ethambutol, rifampicin, and streptomycin [INH-EMB-RM-SM]). In 27 strains submitted to RFLP analysis, the number of copies of IS6110 varied from 6 to 17. Similarity coefficients revealed five distinct groups.(ABSTRACT TRUNCATED AT 250 WORDS)

Antitubercular Agents↗
PubMed1995

[Ofloxacin-cycloserine-protionamide-INH combination against treatment refractory lung tuberculosis].

Multiresistant tuberculoses are on the increase. The conversion rates in "additional" therapy are only modest. 17 multiresistant patients and 6 treatment-refractory tuberculoses were treated by us with ofloxacin-cycloserin-protionamide-INH. 16 of these patients were HIV positive. 21 patients converted after 3 months of treatment by the latest. 3 patients died of HIV syndrome. There was otherwise no difference between HIV positive and HIV negative patients. As a rule, the combination was well tolerated. In multiresistant tuberculosis, it is mandatory to administer at least 3 drugs to which there is no resistance.

AIDS-Related Opportunistic Infections↗
PubMed1995

Restriction fragment length polymorphism (RFLP) analysis and tuberculosis epidemiology.

In order to study polymorphisms of the DNA insertion sequence 6110 (IS6110) in Mycobacterium tuberculosis strains isolated from Colombian patients, together with resistance to antituberculous medications in the Department of Quindío, Colombia, a prospective study was conducted using a consecutive sample of 59 patients with symptomatic pulmonary tuberculosis whose cases had been confirmed by bacilloscopy, both with and without a history of treatment. The patients, who were participating in the Tuberculosis Control Program of the Regional Health Institute of Quindío in Armenia, included all individuals attending local health centers and hospitals between March and July 1993 who were referred to the regional institute. Sputum specimens from each patient were cultured and subjected to drug sensitivity tests. Subsequently, restriction fragment length polymorphisms (RFLP) of IS6110 from 27 patients were analyzed. The patients' treatment histories were used to classify their cases according to WHO criteria. Forty-five cultures were found positive, 44 for M. tuberculosis and 1 for M. africanum. Initial drug resistance was observed in 4 of 42 new cases, or 9.5% (95% CI: 0.6, 18), 2 showing resistance to isoniazid (INH) and 2 to isoniazid plus streptomycin (INH-SM). Acquired resistance was observed in 2 of the 3 chronic cases and relapses, the bacteria being resistant to isoniazid, rifampicin, and streptomycin (INH-RM-SM) in one case and to isoniazid, ethambutol, rifampicin, and streptomycin (INH-EMB-RM-SM) in the other. In those 27 strains subjected to RFLP analysis, the number of copies of IS6110 ranged from 6 to 17. Similarity coefficients revealed five distinct groups of strains. Overall, the RFLP analysis permitted most of the strains to be distinguished from one another, implying that the polymorphisms involved are sufficient to permit effective employment of this technique, which appears to have considerable potential for use in epidemiologic studies and in work designed to provide a basis for tuberculosis control program decision-making.

Chromosome Mapping↗