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M Salfinger

Publications and source records attributed to M Salfinger.

At least 37 records · Page 2Linked to original sources
PubMed1994

Mycobacterial identification by computer-aided gas-liquid chromatography.

The suitability of the Microbial Identification System (MIS) marketed by Microbial ID (Newark, DE, USA) for routine diagnosis of clinically important mycobacteria was investigated and assessed. Cellular fatty acids were extracted from 1077 stock and recent clinical isolates. They were analyzed using a gas-liquid chromatograph combined with MIS software. The MIS system finally identifies the isolates by comparing their fatty-acid compositions with a standard library for mycobacteria. As the library search usually results in more than one possible match, suitable identification criteria were determined. The stricter these criteria are, the more the percentage of false-positive identifications can be reduced, but at the cost of more cases that remain undecided and require additional analysis. Under conditions similarity index (SI) SI1 > or = 0.4 and SI1-SI2 > or = 0.1, 63% of all isolates were correctly and 6% incorrectly identified.

Chromatography, Gas↗
PubMed1994

Characterization of rifampin-resistance in pathogenic mycobacteria.

The emergence of rifampin-resistant strains of pathogenic mycobacteria has threatened the usefulness of this drug in treating mycobacterial diseases. Critical to the treatment of individuals infected with resistant strains is the rapid identification of these strains directly from clinical specimens. It has been shown that resistance to rifampin in Mycobacterium tuberculosis and Mycobacterium leprae apparently involves mutations in the rpoB gene encoding the beta-subunit of the RNA polymerases of these species. DNA sequences were obtained from a 305-bp fragment of the rpoB gene from 110 rifampin-resistant and 10 rifampin-susceptible strains of M. tuberculosis from diverse geographical regions throughout the world. In 102 of 110 rifampin-resistant strains 16 mutations affecting 13 amino acids were observed. No mutations were observed in rifampin-susceptible strains. No association was found between particular mutations in the rpoB gene and drug susceptibility patterns of multidrug-resistant M. tuberculosis strains. Drug-resistant M. tuberculosis strains from the same outbreak and exhibiting the same IS6110 DNA fingerprint and drug susceptibility pattern contained the same mutation in the rpoB gene. However, mutations are not correlated with IS6110 profiling outside of epidemics. The evolution of rifampin resistance as a consequence of mutations in the rpoB gene was documented in a patient who developed rifampin resistance during the course of treatment. Rifampin-resistant strains of M. leprae, Mycobacterium avium, and Mycobacterium africanum contained mutations in the rpoB gene similar to that documented for M. tuberculosis. This information served as the basis for developing a rapid DNA diagnostic assay (PCR-heteroduplex formation) for the detection of rifampin susceptibility of M. tuberculosis.

Amino Acid Sequence↗
PubMed1994

Stability of DNA fingerprint pattern produced with IS6110 in strains of Mycobacterium tuberculosis.

To assess the stability of IS6110 restriction fragment length polymorphism patterns, DNA fingerprints of 6 Mycobacterium bovis isolates from 1 patient and of 41 Mycobacterium tuberculosis isolates from 18 patients were compared. The fingerprint pattern for a given patient remained identical or nearly identical despite recovery of the isolates during intervals which ranged from 8 months to 4.5 years. Changes in drug resistance profile did not alter a strain's fingerprint pattern.

DNA Fingerprinting↗
PubMed1994

[Mycobacteriosis of ornamental birds--frequency, pathologo-anatomic, histologic and microbiologic data].

Mycobacteriosis was diagnosed in 146 (3.8%) of 3801 necropsied pet birds between 1986 und 1991. Gross changes in 62 pet birds with histologically and culturally confirmed mycobacteriosis were predominantly enlargement of liver and spleen and thickening of intestinal walls. Three histological patterns could be observed: granulomas, sheet-like proliferations of mycobacteria-laden epithelioid cells and single scattered macrophages filled with acid-fast bacteria. Mycobacteria grew in 27 (43.6%) of 62 cultures, but the species could only be identified in 13 (21.0%) cases (5 x M. avium-Complex, 3 x M. genavense, 2 x M. fortuitum, 1 x M. gordonae, 1 x M. nonchromogenicum and 1 x M. tuberculosis). The significance of mycobacteriosis in pet birds as a zoonosis remains to be determined.

Animals↗
PubMed1994

The role of the microbiology laboratory in diagnosing mycobacterial diseases.

Recent surveys show that many mycobacteriology laboratories continue to use less-than-optimal culture and susceptibility methods. This review summarizes available methods to diagnose. Mycobacterium tuberculosis. Although the local epidemiologic characteristics of M tuberculosis will partially determine what diagnostic measures are used, all laboratories should use a broth culture method in addition to a solid medium when culturing for M tuberculosis. Laboratories serving communities where drug resistance is common should use the BACTEC system for susceptibility testing or send isolates to a laboratory that uses it. Conventional testing in this setting must be aggressively discouraged. Rapid genetic amplification methods to detect mycobacteria in clinical specimens can greatly reduce the time needed to diagnose tuberculosis, especially if these methods can reliably detect M tuberculosis in smear-negative specimens. Many other diagnostic methods are being developed and clinicians and laboratories must regularly reassess whether a new method would be beneficial to their patients and the public.

Bacteriological Techniques↗
PubMed1993

[Incidence of resistance of tuberculosis bacteria in Switzerland].

Based on a survey, results on resistant tubercle bacilli in Switzerland during October 1987 through April 1991 are presented. In 94% of 2482 tuberculosis cases reported, susceptibility testing results have been available. The radiometric BACTEC technique was used in 76%. Resistance was detected radiometrically for INH in 7%, for rifampin in 1.9% and for ethambutol in 0.7%. The age-specific resistance among Swiss was 12% in the youngest and 3% in the oldest age group. In patients from South American and from Far Eastern countries, INH and rifampin resistance was the highest. Resistance was found in 5.7% of the Swiss and in 7.5% of all. In addition, suggestions for the surveillance of resistant tubercle bacilli have been made.

Adolescent↗
PubMed1993

[Multiresistant tuberculosis in New York].

New Yorkers have to deal with a tuberculosis situation which is of greater extent and a health-care system which is less prepared than in the sixties. Poverty and the HIV epidemic have had a negative impact on the control of tuberculosis. The emergence of nosocomial multidrug-resistant tuberculosis has created an explosive situation. In 1991, rifampin resistance was 33% in patients who had received antituberculosis therapy and 10% among the patients who had never been treated.

AIDS-Related Opportunistic Infections↗
PubMed1993

Invasive infection with Mycobacterium genavense in three children with the acquired immunodeficiency syndrome.

Three children with human immunodeficiency virus infection and invasive infection with Mycobacterium genavense are reported. Fever spikes, abdominal cramps and distension, diarrhea or ileus, and anemia were the predominant symptoms in the severely immunodeficient patients (CD4 lymphocytes < 0.04 x 10(9)/l). Numerous acid-fast bacilli were readily detectable by microscopy in stool samples and in lymph node biopsies, but cultures for mycobacteria remained negative. Mycobacterium genavense should be sought when invasive non-tuberculous mycobacteriosis is suspected and mycobacterial cultures from blood or other sites show limited growth. Multiple-drug regimens including amikacin, ethambutol, rifampin, and clarithromycin may be of benefit in controlling the infection, as observed in two patients.

AIDS-Related Opportunistic Infections↗
PubMed1993

Extrapulmonary and disseminated infections due to Mycobacterium malmoense: case report and review.

Mycobacterium malmoense is a potentially pathogenic species that was first described in 1977. During the past decade M. malmoense has been recognized with increasing frequency as a pulmonary pathogen. More than 180 cases of M. malmoense infection have been reported. Most of these infections affected a previously damaged lung. Other infection sites included the skin, lymph nodes, and bursae. Five cases of disseminated infection have been reported. The antituberculous drugs associated with the most favorable susceptibility patterns are rifampin and ethambutol. Because of the slow growth of M. malmoense on conventional, egg-based bacteriologic media, the incubation time should be > 6 weeks; special solid and liquid media are recommended. We report a case of disseminated pulmonary and gastrointestinal infection due to M. malmoense in a patient with AIDS, who was treated successfully with a combination of rifabutin (ansamycin), clofazimine, and isoniazid. In addition, we review the characteristics of extrapulmonary and disseminated infections due to M. malmoense.

AIDS-Related Opportunistic Infections↗
PubMed1993

Mycobacteriosis due to Mycobacterium genavense in six pet birds.

Six cases of mycobacteriosis due to Mycobacterium genavense in three budgerigars (Melopsittacus undulatus), one orange-winged amazon (Amazona amazonica), one flycatcher (Cyanoptila cyanomelana), and one zebra finch (Taeniopygia guttata) are discussed. Gross lesions associated with the infection included a high degree of muscular wasting (five cases), hepatomegaly (four cases), and thickening of the wall of the small intestine (four cases). Granulomas were found in the lung (one case) and the subcutis (one case). Acid-fast bacilli were detected in the liver of all six birds. Only the use of acidic BACTEC mediums consistently led to growth, whereas the egg-based medium failed. These findings point to a possible role of the environment as a reservoir for M. genavense.

Animals↗
PubMed1993

Mycobacteria in stool specimens: the nonvalue of smears for predicting culture results.

A previous recommendation suggests that stool be cultured for mycobacteria only if the smear is positive. We have correlated smear and culture results of 2,176 stool specimens submitted for mycobacterial culture. The sensitivity, specificity, and positive and negative predictive values for smears to predict culture results are 34, 99, 90, and 87%, respectively. We recommend that the stool smear not be used as a screening technique to decide which specimens from at-risk patients should be cultured because it lacks the necessary sensitivity.

AIDS-Related Opportunistic Infections↗
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↗