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B E Reisberg

Publications and source records attributed to B E Reisberg.

14 recordsLinked to original sources
PubMed1998

Cross-contamination of specimens with Mycobacterium tuberculosis: clinical significance, causes, and prevention.

At the Veterans Affairs Lakeside Medical Center, two episodes of specimen cross-contamination with Mycobacterium tuberculosis were detected during a 54-month period by molecular strain typing using DNA restriction fragment length polymorphism for 3 patients without clinical or radiologic signs of tuberculosis (TB). A cross-contaminated specimen was the only culture-positive specimen for each of the 3 patients. Laboratory features of cross-contamination included acid-fast smear negativity, growth only in broth or solid medium, and growth in solid medium with 5 or fewer colonies. Retrospective analysis demonstrated identical features for occasional culture-positive specimens from 54 patients with TB during the same period. However, productive cough, pleural pain, weight loss, night sweats, chest radiograph results suggestive of TB, positive tuberculin skin testing, and/or multiple culture-positive specimens were invariably present in patients with TB with such specimens. Most patients with TB (50/54; 93%) had multiple specimens positive in culture for M. tuberculosis, and the few patients with TB with single culture-positive specimens were symptomatic. These results indicate that correlation with clinical manifestations is necessary to determine the significance of isolated, acid-fast smear negative, and/or low-yield culture-positive specimens. Although the prevalence of specimen cross-contamination is low (0.1%), possible sources (especially the use of single-reagent delivery systems for multiple specimens) should be eliminated by mycobacteriology laboratories.

Adult↗
PubMed1996

Use of in-house studies of molecular epidemiology and full species identification for controlling spread of vancomycin-resistant Enterococcus faecalis isolates.

Infection with multidrug-resistant (MDR) organisms is a major clinical challenge, and few, if any, therapeutic options remain available. Increasingly, infection control measures have taken on greater importance in preventing the nosocomial transmission of MDR organisms. During December 1994 and January 1995, we identified a cluster of vancomycin-resistant Enterococcus faecalis isolates involving 16 patients situated in different areas of our university-affiliated teaching hospital. Initial review of laboratory requisition forms for the patients' locations revealed no common association, suggesting that the occurrence was not due to horizontal spread. However, using genomic DNA extraction, restriction enzyme analysis, and gel electrophoresis, we found that 12 patients were infected with isolates originating from a single clone, 2 other patients were infected with isolates from a different clone, and the remaining 2 patients were infected with unique strains. Because the typing data suggested nosocomial spread, chart review was undertaken to determine a possible common exposure source. With three exceptions, clonal isolates were linked to patient movement between surgical floors, intensive care units, and a rehabilitation unit. A detailed review of patient records revealing the association would not have been performed without realization of clonality. Thus, the data demonstrate the utility of genomic typing for epidemiological purposes. In turn, targeted infection control measures that halted the spread of the potentially lethal MDR pathogen were instituted.

Anti-Bacterial Agents↗
PubMed1985

Nosocomial Pseudomonas pickettii colonization associated with a contaminated respiratory therapy solution in a special care nursery.

Pseudomonas pickettii caused respiratory tract colonization in five infants in the special care nursery of a Chicago hospital. All organisms had the same antimicrobial susceptibilities. Endotracheal suctioning with saline from 5-ml unit-dose vials was identified by epidemiologic investigation as a risk factor for colonization. The vials of saline were contaminated with a strain of P. pickettii having the same antimicrobial susceptibility pattern as the isolates from patients. As part of an investigation of the manufacturing plant where the saline solution was produced, P. pickettii was recovered from deionized water used to make the product and from several sites in the processing line. Bypassing of a 180 degrees F (ca. 82 degrees C) water-holding tank appeared to be temporally related to product contamination. The ability of P. pickettii to survive and grow in this solution has been demonstrated in the laboratory. This outbreak demonstrates that, despite pertinent Food and Drug Administration regulations and company programs for identifying such contamination, intrinsically contaminated solutions can occasionally reach the bedside of the patient.

Cross Infection↗
PubMed1971

Cephalexin: absorption and excretion as related to renal function and hemodialysis.

Cephalexin is a new semisynthetic cephalosporin C derivative, which is well absorbed from the gastrointestinal tract and excreted in high concentration in the urine. Even in patients with impaired renal function, the concentrations of cephalexin present in the urine are adequate for the treatment of most urinary tract infections produced by Escherichia coli, Klebsiella, and Proteus mirabilis. In anephric patients, single doses of 250 or 500 mg of cephalexin resulted in high, prolonged serum concentrations. Peak levels were usually observed within 1 hr. However, in two of six anephric patients, peak levels were reached after 6 and 12 hr due to delayed absorption. Hemodialysis for 6 hr reduced the serum concentration of cephalexin by 58%.

Journal Article↗
PubMedDate not supplied

Infective endocarditis in the narcotic addict.

As long as the illicit use of heroin and other drugs continues in our society, infective endocarditis will remain a significant medical problem in the drug-using population. The majority of infections are produced by S. aureus, and the tricuspid valve is most commonly involved. Addicts, unlike the general population, may also develop endocarditis with a variety of gram-negative bacilli and have a higher incidence of fungal infection. The outcome of each individual infection is dependent on the prompt recognition of the underlying valvular infection and the institution of antimicrobial therapy. Infection of the tricuspid valve has a much more favorable prognosis than does infection of the aortic or mitral valves. Fungal endocarditis, and frequently gram-negative bacillary endocarditis, require valvular surgery to effect a cure.

Adult↗
PubMedDate not supplied

Molecular typing for investigating an outbreak of Candida krusei.

Invasive infections due to Candida krusei are often observed in immunocompromised patients who have received prior therapy with fluconazole, although infection has also occurred in patients in the absence of this antifungal agent. From August 25 through September 19, 1995, we identified four patients with C. krusei fungemia on our hematology/oncology unit. Molecular typing of all the isolates was performed by restriction endonuclease analysis of genomic DNA using HinfI. A total of 7 patients found to be colonized or infected with C. krusei were matched with 14 controls. There was no difference between the cases and controls with respect to underlying disease, duration of hospitalization, or neutropenia. The numbers of days of hyperalimentation, corticosteroids, and antibiotics were similar between both groups. The mean number of antibiotics was greater in the cases versus controls (5.0 versus 2.5; p = .003). There was no difference with respect to total dose or duration of fluconazole administration. Molecular typing of the isolates revealed that four had identical DNA banding patterns, plus another two that differed by one band and were considered related. Three historical strains were unrelated. In conclusion, this report demonstrates that molecular typing can be used to define clonality and, thereby, support increased infection control practices to eliminate such outbreaks when evidence of clonal spread is present.

Amphotericin B↗