PubMed Health⌕ Search

Biomedical subjects

M Salfinger

Publications and source records attributed to M Salfinger.

At least 19 recordsLinked to original sources
PubMed1992

Epidemiology and clinical significance of nontuberculous mycobacteria in patients negative for human immunodeficiency virus in Switzerland.

Over the last decades, the rate of isolation of tubercle bacilli has declined in the developed countries, while the incidence of infection with nontuberculous mycobacteria (NTM) has increased. In a retrospective study, we analyzed all cases of patients negative for human immunodeficiency virus (HIV) and from whom NTM were isolated in the Zurich area of Switzerland from 1983 to 1988. During the 6-year study period, 513 patients infected with NTM were identified, 34 of whom had clinically significant disease. The presentation of mycobacteriosis was found to be lung disease in 23 cases, soft-tissue disease in 10 cases, and disseminated disease in one case. The highest attack rate of pulmonary mycobacteriosis was 0.49% and was found in the group of patients 41-50 years old. During the 6-year period, the incidence of tuberculosis declined from 16.2 to 13.2 per 100,000 population, while the incidence of mycobacteriosis increased from 0.4 to 0.9 per 100,000 population. Clinically nonsignificant NTM isolates were found more frequently in patients with chronic lung diseases (P less than .01) and especially in patients with a history of tuberculosis (P less than .001).

Adolescent↗
PubMed1992

Pseudoepidemic of nontuberculous mycobacteria due to a contaminated bronchoscope cleaning machine. Report of an outbreak and review of the literature.

We describe a pseudoepidemic due to nontuberculous mycobacteria contaminating the water tank of a machine used to clean and disinfect fiberoptic endoscopes. Forty-six bronchoscopies performed on 41 patients during a six-month period yielded 16 specimens positive for acid-fast bacilli (AFB). One specimen showed Mycobacterium avium complex from an AIDS patient and one, M tuberculosis from a patient with active cavitary tuberculosis. In four patients, only the smears showed AFB; subsequent cultures remained negative. Of the rest, seven contained M chelonae and three M gordonae, all in patients with no clinical signs of mycobacterial disease. Two of the three M gordonae isolates represented laboratory contamination from an antimicrobial solution in a culture medium. Four patients in the beginning of the pseudoepidemic were treated for presumed tuberculosis until negative culture results were available. Control of the "outbreak" was achieved by regular disinfection of the implicated water tank in the cleaning machine. Contamination of bronchoscopes with nontuberculous mycobacteria can lead to unnecessary diagnostic and therapeutic interventions.

Bronchoscopy↗
PubMed1992

[Mycobacterium malmoense infection of the flexor tendon sheath].

Infections of the tendon sheath caused by non-tuberculous mycobacteria are well known. So far, only one case involving Mycobacterium malmoense has been reported. The authors report of a 73-year old patient having undergone carpal tunnel release. In spite of granulomatous inflammation of the flexor tendon sheaths, there was no biopsy cultured for acid-fast bacteria. One year later, symptoms recurred and synovialectomy was repeated. In spite of macroscopic appearance of the synovialis and histological studies, a specific diagnosis was not yet made. Two weeks later, acid-fast bacteria, identified as M. malmoense were cultured in the BACTEC vial. Because specific treatment was not initiated, a further recurrence developed five months later, necessitating further surgery with synovialectomy. Properly treated with Rifampin and Ethambutal for twelve months, the patient has remained asymptomatic for the following two years.

Aged↗
PubMed1992

The use of radiometric tests in the speciation of mycobacteria--a review.

Besides a more rapid detection and susceptibility testing, radiometry offers possibilities for the identification of mycobacteria. This paper gives a chronological summary of radiometric techniques used in the BACTEC system (Becton Dickinson) for the identification of mycobacterial complexes/species, employing chemical compounds as selective inhibitory agents or for testing biochemical activities. Thirteen tests are presented and discussed.

Mycobacterium↗
PubMed1991

[Diagnosis and treatment of pulmonary infection due to Mycobacterium malmoense].

To date more than 150 patients with Mycobacterium malmoense disease have been reported. These infections are rare and only in one case, so far not published, is this species associated with Aids. Most reported cases were seen in northern Europe. We present three pulmonary cases from Switzerland. M. malmoense causes lung disease resembling tuberculosis clinically and in chest X-ray. Disease is considered to be present when two and more sputums or bronchial washings are acid-fast bacilli smear-positive and culture-positive. M. malmoense grows slowly on egg-based bacteriological media; the incubation time is at least 6 weeks and the use of special solid or liquid media is recommended. Person-to-person transmission is rare and, in contrast to tuberculosis, isolation of the patient is not necessary and subsequent close contact persons do not need to be evaluated. It seems that a combination of isoniazid, rifampicin and ethambutol given for more than 12 months is the best regimen.

Adult↗
PubMed1990

Pyrazinamide and pyrazinoic acid activity against tubercle bacilli in cultured human macrophages and in the BACTEC system.

Pyrazinamide (PZA) has become an essential component of current 6-month regimens for therapy of tuberculosis. Susceptible strains of tubercle bacilli convert PZA to pyrazinoic acid (POA) through pyrazinamidase (PZase), which resistant strains and Mycobacterium bovis bacille Calmette-Guérin lack. PZA susceptibility results obtained in cultured human macrophages were compared with those in the broth BACTEC system with 7H12 medium at pH 6.0 for strains known to be PZase-positive or -negative. Although added POA was unable to inhibit tubercle bacilli in cultured macrophages, it was able to inhibit them at very high concentrations in the BACTEC broth. Intracellularly formed POA would not be able to escape from the macrophage, and therefore would accumulate sufficiently to lower pH to toxic levels for tubercle bacilli. The results suggest that the cultured macrophages contribute actively or passively to the effectiveness of PZA, such as through the proposed mechanism of low pH generated by PZase in the phagolysosomes.

Amidohydrolases↗
PubMed1990

Experience of gas-liquid chromatography in clinical microbiology.

In clinical microbiology, gas-liquid chromatography (GLC) is used mainly for the following applications: (1) demonstration of microbial metabolites in cultures: studies of short-chain fatty acids (chain length 2 to 6 carbon atoms) and of the non-volatile lactic and succinic acids are the basis of taxonomy of obligate anaerobes on the genus level. Demonstration of these compounds in spent culture media is also used for identification of anaerobic bacteria in the clinical laboratory. (2) Investigation of long-chain fatty acids of cell membranes and the cell wall: analysis of fatty acids with chain lengths of 9 to 20 carbon atoms are used primarily for taxonomic purposes. A practical application for use in clinical bacteriology is the Microbial Identification System (MIS) based on equipment built by Hewlett-Packard. Although this system is excellently suited for quantitative analysis of long chain fatty acids and gives valuable preliminary or confirmative information, it often requires additional testing for identification of bacteria to species level. (3) Direct rapid diagnosis of infection: demonstration of metabolic products in body fluids can be of value in infections with anaerobes (demonstration of fatty acids) and yeasts (sugars). GLC combined with mass spectrometry or frequency-pulsed electron capture GLC techniques have been applied to studies of sera, fecal specimens, and cerebrospinal fluids. These latter applications are still in an experimental stage. However, the rapid diagnosis of tuberculosis directly from cerebrospinal fluid and sputum is well advanced. The potential of direct diagnosis without the resort to cultures warrants continued research with these techniques.

Bacteria, Anaerobic↗
PubMed1989

1,25(OH)2-vitamin D3 synergizes with pyrazinamide to kill tubercle bacilli in cultured human macrophages.

Pyrazinamide (PZA) is believed to be mycobactericidal in vivo. Because it is ineffective at neutral pH in vitro, it is thought to owe its in vivo activity at least partly to acting upon tubercle bacilli (TB) in the helpfully low pH of macrophage (MP) phagolysosomes. However, when it was tested in TB-infected cultured human MP, it was not bactericidal and was able only to slow intra-MP bacillary growth. Recent evidence has suggested that human MP need hormonal support from certain vitamin D metabolites to resist TB. This support was not provided in the culture medium of the earlier experiments in which the PZA was relatively ineffective. Here, PZA has been retested in MP cultured in medium supplemented with the hormonally active metabolite of vitamin D, 1,25(OH)2-vitamin D3 (1,25D3). The MP were infected with virulent TB and incubated in various concentrations of PZA. 1,25D3 was added to postinfection medium at 4 micrograms/ml. Inhibition or killing of intracellular TB was quantitated by counts of culturable TB from samples of lysed MP taken at zero, 4, and 7 days after MP infection. Previous evidence for the protectiveness of 1,25D3 alone for human MP against TB was confirmed. The weak inhibition of TB in MP by PZA alone also was confirmed. The two used together synergized to decrease concentrations of PZA which were inhibitory and to switch the action of PZA from weakly inhibitory to bacteriostatic or mildly bactericidal. 1,25D3 had no direct anti-TB effect, and it did not synergize with PZA in the absence of MP, as determined with acidified bacteriologic culture medium in the BACTEC radiometric system.(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1988

Identification of contaminants during primary isolation of mycobacteria in the BACTEC system with the antimicrobial supplement PACT.

1500 sputum specimens and bronchial washings were cultured for mycobacteria. One half of the specimen was treated with N-acetyl-L-cysteine--sodium hydroxide (3%) (NALC) and the other with sodium dodecyl (lauryl) sulfate--sodium hydroxide (1%) (SDS). The different species of contaminants found with each pretreatment method with the BACTEC radiometric system were identified. Contamination occurred in 6% by using SDS and in 10% by using NALC. The SDS method was more effective against Bacillus ssp. and Streptomyces ssp., the major contaminants. However, the growth of Pseudomonas ssp. was a problem in both methods.

Acetylcysteine↗
PubMed1988

Comparative in-vitro activity of fleroxacin and other 6-fluoroquinolones against mycobacteria.

The susceptibility of 11 clinical isolates of Mycobacterium tuberculosis, 3 M. kansasii, 3 M. xenopi, 2 M. scrofulaceum, 2 M. marinum, 2 M. malmoense to fleroxacin, ciprofloxacin, norfloxacin, rifampicin, isoniazid, ethambutol, and streptomycin was determined by the standard proportion method (Middlebrook 7H10 agar). All M. tuberculosis, M. kansasii, M. xenopi, M. scrofulaceum, M. marinum, and M, malmoense isolates including those resistant to conventional antimycobacterials were inhibited by 0.5 mg/l of fleroxacin and ciprofloxacin, the lowest tested concentration. Fleroxacin and ciprofloxacin along with ofloxacin, pefloxacin, ansamycin, clofazimine and cycloserine were also tested against 14 isolates of the M. avium complex. Nine of 14 strains (64%) of the M. avium complex were found susceptible to 4 mg/l of fleroxacin and a similar percentage to the other quinolones. On the basis of its in-vitro potency and its favourable pharmacokinetic properties fleroxacin appears to be sufficiently active to warrant further experimental trials against difficult to treat mycobacteria.

Anti-Infective Agents↗
PubMed1988

Determination of pyrazinamide MICs for Mycobacterium tuberculosis at different pHs by the radiometric method.

The MICs of pyrazinamide (PZA) were determined for Mycobacterium tuberculosis cultivated under different pH conditions in 7H12 liquid medium. Mycobacterial growth was monitored by the radiometric method (BACTEC system; Johnston Laboratories, Inc., Towson, Md.). We observed a predictable eightfold difference between the MICs determined at pH 5.5 and those determined at pH 5.95. The highest MICs for 21 susceptible strains were 50.0 micrograms/ml at pH 5.5 and 400 micrograms/ml at pH 5.95. This eightfold difference enabled us to predict MICs at pH 5.5 from the values observed at pH 5.95. The use of 7H12 broth at pH 5.95 simplified the radiometric PZA susceptibility test by avoiding the addition of acid solutions in the course of cultivation, which was required when the test was performed at pH 5.5. An additional benefit of using pH 5.95 instead of pH 5.5 was that all tested strains grew at pH 5.95, while some of them, especially PZA-resistant strains, did not grow at pH 5.5.

Cell Survival↗
PubMed1988

Comparison of three methods for recovery of Mycobacterium avium complex from blood specimens.

Three methods were used for the recovery of mycobacteria from blood specimens obtained from acquired immunodeficiency syndrome patients: (i) inoculation of 7H11 agar plates with a concentrated specimen, (ii) inoculation of 7H12 BACTEC vials with a concentrated specimen, and (iii) inoculation of 7H13 BACTEC vials with a nonconcentrated specimen. In this study, we examined 255 specimens and obtained positive mycobacterial growth in 47 of them. Among these 47 cultures, 40 were found to be positive by all three methods, and the total recovery rates in relation to these culture-positive specimens were 94% for method 1, 89% for method 2, and 96% for method 3. The advantages and disadvantages of these three methods are discussed.

Bacteriological Techniques↗
PubMed1987

Susceptibility testing of Mycobacterium tuberculosis to pyrazinamide.

One hundred and sixty clinical isolates of Mycobacterium tuberculois were tested for their sensitivity to pyrazinamide (PZA) using the conventional proportion method (Middlebrook 7H10 agar) and the results compared to the pyrazinamidase (PZase) activity of the strains. The correlation between strains susceptible to PZA and the production of PZase was 99%. None of the isolates were exclusively resistant to PZA. At present the rate of initial PZA resistance in Kanton Zurich is 0.6%.

Amidohydrolases↗
PubMed1985

[The transmission of mycobacteria through the fiberoptic bronchoscope].

Transmission of Mycobacterium tuberculosis by the flexible fiberoptic bronchoscope was suspected in two patients with positive cultures from bronchial washings but with negative cultures from sputum specimens and no clinical or radiological evidence of active tuberculosis, In both cases, a patient with sputum smear-positive pulmonary tuberculosis had been examined with the same bronchoscope the day before. In one case, mycobacteriophage typing of the cultures of the consecutively examined patients revealed the same phage type in both patients, suggesting transmission by the fiber bronchoscope. In the other case, however, transmission was ruled out by different phage types. Among the few previously reported cases of transmission of Mycobacterium tuberculosis by the flexible fiberoptic bronchoscope, one case of tuberculin conversion occurred. Without antituberculous therapy our patient had negative sputum cultures and no evidence of tuberculosis one year after bronchoscopy. Transmission of other microorganisms and possible causes of transmission by the fiberoptic bronchoscope are reviewed and discussed.

Aged↗