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H D Isenberg

Publications and source records attributed to H D Isenberg.

At least 19 recordsLinked to original sources
PubMed1995

The challenge of vancomycin-resistant enterococci: a clinical and epidemiologic study.

BACKGROUND: Vancomycin-resistant enterococci have been recovered with increasing frequency from hospitalized patients. Risk factors, mode of nosocomial transmission, extent of colonization in hospitalized patients, and treatment options for these organisms have not been completely delineated. METHODS: We studied 53 patients (group A) with vancomycin-resistant enterococci isolated from various clinical specimens and also surveyed for vancomycin-resistant enterococci in stool specimens submitted for Clostridium difficile toxin assays (group B). Stool specimens submitted for identification of bacterial pathogens and stool specimens from hospital employees were also analyzed for vancomycin-resistant enterococci. RESULTS: Seventy-six isolates of vancomycin-resistant enterococci were recovered in group A. Five of these patients harbored vancomycin-resistant enterococci on admission. Fifty-three of 289 group B stool specimens submitted for C. difficile toxin assays yielded vancomycin-resistant enterococci. Cephalosporins and vancomycin were the most common antimicrobial agents received by both groups of patients. Enterococcus faecium isolates were more resistant than Enterococcus faecalis isolates to antimicrobial agents. All isolates exhibited high-level aminoglycoside resistance and were not beta-lactamase producers. There were at least 15 different molecular clones of E. faecium and three of E. faecalis. Vancomycin-resistant enterococcal bacteremia was associated with a 100% in-hospital mortality rate. CONCLUSIONS: Multidrug-resistant and vancomycin-resistant enterococci have become important nosocomial pathogens that are difficult to treat. Vancomycin-resistant enterococcal bacteremia was associated with a poor prognosis. We found a high rate of colonization in patients with suspected C. difficile toxin colitis. Judicious use of vancomycin and broad-spectrum antibiotics is recommended, and strict infection control measures must be implemented to prevent nosocomial transmission of these organisms.

Adult↗
PubMed1995

Association of recurrent candidal vaginitis with inheritance of Lewis blood group antigens.

A subset of women with candidal vulvovaginitis have no known risk factors for recurrent episodes. Although there are reports of an association of blood group antigens with various infections, no such association has been described with candidal vulvovaginitis. The ABO, P1, and Lewis group phenotypes of 35 women with recurrent vulvovaginitis but without other chronic infections were determined. These were compared with those of a control group of 40 women without a history of candidal vulvovaginitis. The distribution of ABO blood types and P blood group phenotype did not differ from those in controls. However, vulvovaginitis patients were more likely than controls to be classified as Lea-b- (chi 2 = 6.4, 1 df, P = .011). Women without known predisposing factors may have a genetic predisposition to recurrent vulvovaginitis, as evidenced by a higher frequency of Lea-b- phenotype profiles compared with controls.

ABO Blood-Group System↗
PubMed1995

Is hand washing really needed in an intensive care unit?

OBJECTIVES: To determine whether a rigorous antiseptic hand washing of bare hands with 4% chlorhexidine and alcohol reduced fingertip microbial colonization as compared with the use of boxed, clean, nonsterile latex gloves. In addition, to investigate if aseptic donning technique and/or a prior hand washing would reduce the level of glove contamination. DESIGN: Prospective, randomized, crossover design, with each subject serving as his/her own control. SETTING: University intensive care unit. SUBJECTS: Forty-three intensive care nurses. INTERVENTIONS: The fingertips of 20 nurses were cultured before and after a strict antiseptic hand washing and before and after the routine and aseptic donning of sterile gloves. Subsequently, the fingertips of 43 nurses were cultured before and after the casual donning of nonsterile gloves over unwashed hands and before and after a strict antiseptic hand washing. Fingertip cultures were plated directly on agar, incubated for 24 hrs, and counted and recorded as the number of colony-forming units (cfu) for each hand. Different colony types were then subcultured. MEASUREMENTS AND MAIN RESULTS: Hand washing with antiseptic reduced colonization from 84 to 2 cfu (p < .001). The proportion of cases with > or = 200 cfu/hand was reduced from 30% to 9%. Aseptic or casual donning of sterile gloves, with or without prior antiseptic hand washing, resulted in consistently low glove counts between 0 and 1.25 cfu. Nonsterile gloves casually donned over washed or unwashed bare hands diminished the bioburden to 2.17 and 1.34 cfu, respectively. No qualitative difference was found in the microorganisms recovered from gloved or bare hands. CONCLUSIONS: Antiseptic hand washing and the use of nonsterile gloves over unwashed hands confer similar reductions in the number of microorganisms. There is no additional benefit with the use of aseptic donning technique, prior antiseptic hand washing, or the use of individually packaged sterile gloves.

Asepsis↗
PubMed1994

Community-acquired soft-tissue infections caused by Flavimonas oryzihabitans.

Flavimonas oryzihabitans has rarely been implicated in human infections. Previously reported cases of infections caused by this bacterium were nosocomially acquired. We report two cases of community-acquired soft-tissue infections due to F. oryzihabitans. It remains unclear how the patients were exposed to the organism.

Abscess↗
PubMed1994

Clostridium bifermentans bacteremia with metastatic osteomyelitis.

Osteomyelitis caused solely by an anaerobic organism is uncommon. We report a case of recurrent Clostridium bifermentans bacteremia resulting in metastatic osteomyelitis involving the sacrum, spine, and ribs. The emergence of resistance of this organism to imipenem and metronidazole is noteworthy because of the usual susceptibility of clostridial species to these antibiotics.

Aged↗
PubMed1994

Genotypic variation and slime production among blood and catheter isolates of Candida parapsilosis.

Candida parapsilosis is an important nosocomial pathogen that can proliferate in high concentrations of glucose and form biofilms on prosthetic materials. We investigated the genotypic diversity and slime production among 31 isolates of C. parapsilosis from individual patients with bloodstream or catheter infections. DNA subtyping was performed by using electrophoretic karyotyping plus restriction endonuclease analysis with BssHII followed by pulsed-field gel electrophoresis. Slime production was evaluated by growing organisms in Sabouraud broth with 8% glucose and examining the walls of the tubes for the presence of an adherent slime layer. Overall there were 14 DNA subtypes among the 31 isolates. Eighty percent of the isolates produced slime; 67% of the isolates were moderately to strongly positive, 13% were weakly positive, and 20% were not slime producers. The ability of isolates of a given DNA type to produce slime under these conditions was variable. The results of these studies indicate moderate genotypic variation among clinical isolates of C. parapsilosis. The propensity of these isolates to form slime in glucose-containing solutions suggests that this phenotypic characteristic may contribute to the ability of C. parapsilosis to adhere to plastic catheters and cause infections.

Candida↗
PubMed1992

Ingestion of yogurt containing Lactobacillus acidophilus as prophylaxis for candidal vaginitis.

OBJECTIVE: To assess whether daily ingestion of yogurt containing Lactobacillus acidophilus prevents vulvovaginal candidal infections. DESIGN: Crossover trial for at least 1 year during which patients were examined for candidal infections and colonizations while receiving either a yogurt-free or a yogurt-containing diet. Patients served as their own controls. SETTING: Ambulatory infectious disease center in a teaching hospital providing tertiary care. PATIENTS: Thirty-three women with recurrent candidal vaginitis were eligible after recruitment from community practices and clinics and through advertising. Twelve patients were eliminated for protocol violations. Of the remaining 21 patients, 8 who were assigned to the yogurt arm initially refused to enter the control phase 6 months later. Thus, 13 patients completed the protocol. INTERVENTIONS: Women ate yogurt for 6 months of the study period. MEASUREMENTS: Colonization of lactobacilli and candida in the vagina and rectum; candidal infections of the vagina. MAIN RESULTS: Thirty-three eligible patients were studied. A threefold decrease in infections was seen when patients consumed yogurt containing Lactobacillus acidophilus. The mean (+/- SD) number of infections per 6 months was 2.54 +/- 1.66 in the control arm and 0.38 +/- 0.51 per 6 months in the yogurt arm (P = 0.001). Candidal colonization decreased from a mean of 3.23 +/- 2.17 per 6 months in the control arm to 0.84 +/- 0.90 per 6 months in the yogurt arm (P = 0.001). CONCLUSION: Daily ingestion of 8 ounces of yogurt containing Lactobacillus acidophilus decreased both candidal colonization and infection.

Adult↗
PubMed1992

Vancomycin-resistant Enterococcus faecium in hospitalized children.

OBJECTIVE: Determine the epidemiology and risk factors for colonization with vancomycin-resistant Enterococcus faecium. DESIGN: Survey; case-control study. SETTING: Children's hospital. PATIENTS: Pediatric oncology patients. INTERVENTION: Contact isolation, restriction of vancomycin prescribing. RESULTS: There was a high prevalence of colonization with vancomycin-resistant enterococci among pediatric oncology patients. The length of hospitalization and the administration of vancomycin and other intravenous antibiotics was associated with colonization. Prevention of colonization was associated with restriction of vancomycin use and contact isolation. CONCLUSIONS: Vancomycin use may predispose to colonization with vancomycin-resistant E faecium. Vancomycin-resistant E faecium may be nosocomially spread. Contact isolation and restriction of vancomycin use may prevent spread of vancomycin-resistant E faecium.

Bacterial Typing Techniques↗
PubMed1992

Clinical significance of Staphylococcus warneri bacteremia.

Twenty-seven episodes of bacteremia caused by Staphylococcus warneri were identified at Long Island Jewish Medical Center in New York between 1984 and 1989. Fourteen of these were thought to represent true bacteremias and 13 to represent contaminants. Of the 14 true bacteremias, 5 were in pediatric and 9 were in adult patients. Eight of 14 patients (57%) had catheter-related bacteremia and 5 of 14 had bacteremia of unknown source. There was one case of fulminant native valve S. warneri endocarditis. All cases of catheter-related bacteremia, except one, were nosocomially acquired, and 75% of these patients had an underlying immunosuppressive condition. Only 40% of patients with bacteremias of unknown source were immunocompromised, and S. warneri appeared to be noninvasive in this group. Interestingly, all five of the pediatric isolates were oxacillin susceptible, although four of five were resistant to penicillin, despite the fact these patients were hospitalized an average of 29 days. In contrast, seven of nine adult isolates were resistant to both oxacillin and penicillin. The only case of native valve S. warneri endocarditis occurred in a patient who had no known underlying valvular heart disease, but had an underlying immunosuppressive condition. Identification to species level of coagulase-negative staphylococci may lead to appreciation of the importance of bacteria such as S. warneri as human pathogens.

Adolescent↗
PubMed1992

Abscess and empyema caused by Legionella micdadei.

Legionella micdadei is the second most common species implicated in the occurrence of Legionella pneumonia (D. J. Bremer, Semin. Respir. Infect. 4:190-205, 1987). Although there has been a reported lung abscess caused by dual infection (L. micdadei and L. pneumophila), there are no known cases of L. micdadei as the only causative organism. We report a case of a patient with a lung abscess from which L. micdadei was the sole organism isolated.

Empyema↗
PubMed1991

Evaluation of the Roche Septi-Chek AFB system for recovery of mycobacteria.

The Septi-Chek AFB system for the recovery of mycobacteria from clinical specimens was compared with a conventional approach using Lowenstein-Jensen and Middlebrook 7H11 agars. A total of 1,532 clinical specimens were analyzed; 132 yielded mycobacteria. Mycobacterium tuberculosis and Mycobacterium avium complexes were the predominant isolates. With the conventional combination of Lowenstein-Jensen and 7H11 agars, 75.8% of the isolates were recovered; the Septi-Chek AFB allowed recovery of 100% of the isolates. Septi-Chek AFB required less time for the detection of mycobacteria than did the conventional media.

Agar↗
PubMed1991

Restriction fragment analysis of a Candida tropicalis outbreak of sternal wound infections.

An apparent single-source outbreak of Candida tropicalis sternal wound infections in eight patients was investigated by utilizing DNA restriction fragment analysis (RFA) with HindIII and BstNI. All eight outbreak isolates appeared to be identical and were easily differentiated from control isolates by DNA RFA. Compared with an arbitrarily selected reference outbreak isolate, greater than or equal to 95% of the bands in the restriction digests identified by a computerized image analysis system from each of the outbreak isolates were identical versus 13 to 53% of the bands in any of the nine control isolates. Outbreak strains were significantly more likely to match the reference outbreak isolate than were controls (P less than 0.0001). The RFA was greatly facilitated by the use of computerized image analysis and confirmed the epidemiologic link between a scrub nurse and the infected patients.

Candida↗
PubMed1991

Candida zeylanoides: another opportunistic yeast.

A patient with a long history of scleroderma and gastrointestinal malabsorption requiring total parenteral nutrition was admitted with Candida zeylanoides fungemia. The yeast responded to therapy, but on two subsequent admissions for episodes of fever the blood cultures yielded the same yeast. The identity of the Candida species was established biochemically by both the API (Analytab) and Vitek system approaches. C. zeylanoides ATCC 20356 and ATCC 7351 served as controls for these analyses and for antifungal susceptibility studies and restriction endonuclease analyses of chromosomal DNA. These investigations indicated that representative isolates of the yeasts from the three episodes were identical and differed in several respects from the ATCC strains, which did not share many of the characteristics bands with the DNA restriction fragment analysis. C. zeylanoides variants capable of tolerating 35 degrees C can complicate the recovery of patients, especially individuals compromised by their underlying disease.

Amphotericin B↗
PubMed1991

Collaborative feasibility study of a biphasic system (Roche Septi-Chek AFB) for rapid detection and isolation of mycobacteria.

A study to delineate the feasibility of a biphasic-culture approach for detection and isolation of mycobacteria from clinical specimens except blood was conducted in four medical centers. The biphasic system (Septi-Chek AFB, Roche Diagnostic Systems, Nutley, N.J.) was compared with conventional mycobacterial isolation media and the BACTEC system. Septi-Chek AFB showed the highest degree of mycobacterial recovery. In addition, Septi-Chek AFB consistently shortened the time required for recovery of mycobacteria from clinical specimens and supported the growth of small inoculum numbers of stock cultures of 14 mycobacterial species. The study indicates the feasibility and potential advantages of the biphasic approach for detection and isolation of mycobacteria.

Bacteriological Techniques↗
PubMed1989

Single-source outbreak of Candida tropicalis complicating coronary bypass surgery.

Candida tropicalis was isolated from the sternal wounds of eight coronary bypass patients from 18 to 89 days postoperatively; infections were limited to soft tissue in five patients but involved the sternum in three patients. Analysis of surgery records implicated one individual as the potential source of the yeast; this was confirmed by microbiological studies of fingertips and nasopharynx cultures of all personnel in contact with these patients. Only the suspect nurse, then acting as a scrub nurse and not as a circulator, infected the eight patients. Her removal from the cardiac team terminated the cluster outbreak.

Candida↗