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D Kaye

Publications and source records attributed to D Kaye.

At least 55 records · Page 3Linked to original sources

An assessment of the usefulness of the Duke criteria for diagnosing active infective endocarditis.

We evaluated the usefulness of the Duke criteria for diagnosing cases of active infective endocarditis (IE). Patients were identified prospectively over a 3-year period at 54 hospitals in the Philadelphia metropolitan area. Three of us independently reviewed abstracted hospital records and classified 410 patients as definite, probable, or possible cases of IE or as probable noncases. We then applied the Duke criteria to this sample to assess the degree of agreement between our diagnoses and the diagnoses based on these new criteria. Agreement was good to excellent, ranging from 72% to 90%, depending on the case definition used. The sensitivity of the Duke criteria was also good to excellent, varying from 71% to 99%, again depending on case definition used. Specificity was lower (0-89%). We conclude that use of the Duke criteria will result in little underdiagnosis of IE but that it may result in overdiagnosis of IE; therefore, these criteria should be applied prospectively to determine their clinical usefulness.

Adult↗

Role of transiently altered sarcolemmal membrane permeability and basic fibroblast growth factor release in the hypertrophic response of adult rat ventricular myocytes to increased mechanical activity in vitro.

One of the trophic factors that has been implicated in initiating or facilitating growth in response to increased mechanical stress in several tissues and cell types is basic fibroblast growth factor (bFGF; FGF-2). Although mammalian cardiac muscle cells express bFGF, it is not known whether it plays a role in mediating cardiac adaptation to increased load, nor how release of the cytosolic 18-kD isoform of bFGF would be regulated in response to increased mechanical stress. To test the hypothesis that increased mechanical activity induces transient alterations in sarcolemmal permeability that allow cytosolic bFGF to be released and subsequently to act as an autocrine and paracrine growth stimulus, we examined primary isolates of adult rat ventricular myocytes maintained in serum-free, defined medium that were continually paced at 3 Hz for up to 5 d. Paced myocytes, but not nonpaced control cells, exhibited a "hypertrophic" response, which was characterized by increases in the rate of phenylalanine incorporation, total cellular protein content, and cell size. These changes could be mimicked in control cells by exogenous recombinant bFGF and could be blocked in continually paced cells by a specific neutralizing anti-bFGF antibody. In addition, medium conditioned by continually paced myocytes contained significantly more bFGF measured by ELISA and more mitogenic activity for 3T3 cells, activity that could be reduced by a neutralizing anti-bFGF antibody. The hypothesis that transient membrane disruptions sufficient to allow release of cytosolic bFGF occur in paced myocytes was examined by monitoring the rate of uptake into myocytes from the medium of 10-kD dextran linked to fluorescein. Paced myocytes exhibited a significantly higher rate of fluoresceinlabeled dextran uptake. These data are consistent with the hypothesis that nonlethal, transient alterations in sarcolemmal membrane permeability with release of cytosolic bFGF is one mechanism by which increased mechanical activity could lead to a hypertrophic response in cardiac myocytes.

Animals↗

Does treatment of asymptomatic bacteriuria in older ambulatory women reduce subsequent symptoms of urinary tract infection?

OBJECTIVE: To determine whether treatment of symptomatic bacteriuria in older ambulatory women affects the subsequent development of symptoms of urinary tract infection. DESIGN: A controlled clinical trial. PARTICIPANTS: Older women not having urinary catheters. MEASUREMENTS: Urine cultures every 6 months (the same organism at 10(5) colony-forming units or more per mL on two midstream urine specimens defined asymptomatic bacteriuria) and questionnaire surveys for the new development of symptoms of urinary tract infection (dysuria, frequency, urgency, low back pain with fever) 1, 3, and 6 months after the initial survey. RESULTS: Of the 23 initially culture-positive participants receiving antibiotic treatment for symptomatic bacteriuria, nine were culture positive at 6 months, which contrasts with 18 of 27 who received no treatment or placebo, P = .05. However, symptoms of urinary tract infection were more common in the antibiotic-treated group. CONCLUSION: Antibiotic therapy effectively reduced the subsequent occurrence of positive urine cultures, but symptoms were not reduced. Based on this study of morbidity, previous studies failing to show any relation to mortality, and the cost and complications of antibiotic therapy in the older population, treatment of asymptomatic bacteriuria in older women is contraindicated.

Activities of Daily Living↗

Natural killer cell cytotoxicity in elderly humans after influenza immunization.

Previous studies have reported that human natural killer (NK) cytotoxicity can be augmented by either in vitro stimulation with influenza virus antigens or in vivo administration of killed influenza vaccine. The study demonstrating the latter conclusion reported an increase in NK cytotoxicity lasting for 4 weeks postvaccination in young subjects. We initiated our study to determine if a similar increase in NK activity was observed in an elderly population after immunization with the 1992-1993 influenza vaccine. NK activity of 34 elderly (mean age, 77.3 years) was determined at 3 time points: prevaccination, 4 to 6 weeks postvaccination, and 5 to 6 months after vaccination. In contrast to the results of the previous study, the NK cytotoxicity of our elderly subjects was not augmented by the influenza vaccine at any time tested. We also determined the number of CD56+ cells in whole-blood samples at each of the time points and found that there is no change in NK cell number after influenza vaccination.

Aged↗

Antibiotic treatment of adults with infective endocarditis due to streptococci, enterococci, staphylococci, and HACEK microorganisms. American Heart Association.

OBJECTIVE: To provide guidelines for the treatment of endocarditis in adults caused by the following microorganisms: viridans streptococci and other streptococci, enterococci, staphylococci, and fastidious gram-negative bacilli of the HACEK group. PARTICIPANTS: An ad hoc writing group appointed by the American Heart Association under the auspices of the Committee on Rheumatic Fever, Endocarditis, and Kawasaki Disease, Council on Cardiovascular Disease in the Young. EVIDENCE: Published studies of the treatment of patients with endocarditis and the collective clinical experience of this group of experts. CONSENSUS PROCESS: The recommendations were formulated during meetings of the working group and were prepared by a writing committee after the group had agreed on the specific therapeutic regimens. The consensus statement was subsequently reviewed by standing committees of the American Heart Association and by a group of experts not affiliated with the working group. CONCLUSIONS: Sufficient evidence has been published that recommendations regarding treatment of the most common microbiological causes of endocarditis (viridans streptococci, enterococci, Streptococcus bovis, staphylococci, and the HACEK organisms) are justified. There are insufficient published data to make a strong statement regarding the efficacy of specific therapeutic regimens for cases of endocarditis due to microorganisms that uncommonly cause endocarditis. As a useful aid to the practicing clinician, the writing group developed a consensus opinion regarding management of endocarditis caused by the most commonly encountered microorganisms and regarding those cases due to infrequent causes of endocarditis.

Adult↗

Incidence of infective endocarditis in the Delaware Valley, 1988-1990.

This population-based study aimed to determine the incidence of native, prosthetic, and bioprosthetic valve nosocomial infective endocarditis (IE), and IE associated with the use of injected drugs. Patients with IE during 27 months over the years 1988 to 1990, and residing in any of 6 counties in the Philadelphia metropolitan area were identified. An expert panel reviewed all patients to verify the diagnosis. Incidence rates were estimated after adjustment for failure to recruit and underreporting. Of 853 potential patients, 670 (79%) met the inclusion criteria. The overall incidence rate of IE was 11.6 cases/100,000 person-years (95% confidence interval [CI] 10.8 to 12.4). The rates for specific types of IE were: 4.45 (95% CI 3.97 to 4.94) for community-acquired native valve, 0.94 (95% CI 0.72 to 1.12) for prosthetic valve, 0.94 (95% CI 0.71 to 1.16) for nosocomial, and 5.34 (95% CI 4.80 to 5.87) for IE associated with use of injected drugs. Previous population studies found overall incidence rates of 1.7 to 4 cases/100,000 person-years, similar to our rate for community-acquired native valve IE. Type-specific rates have not been previously reported. The higher overall rate in this study is partly related to the high prevalence of injection drug use in our area.

Adult↗

Comparing selection criteria of residency directors and physicians' employers.

In 1993, the Medical College of Pennsylvania (MCP), mindful of the rapidly changing environments of health care delivery, created three surveys to gather information from outside the school that would help the faculty plan how the curriculum and advising system could better prepare students and residents for the demands of twenty-first-century medicine. The first survey focused on the MCP seniors graduating that year and asked about their perceptions of their medical education and their specialty and residency choices. The second survey, directed to 40 medical residency program directors in family medicine, internal medicine, pediatrics, and surgery, sought to identify the characteristics of applicants that these directors valued when selecting entrants to their programs. The third survey, of 30 employers of physicians representing four practice environments (private practice, hospitals/other health systems, academic medical centers, and health maintenance organizations), sought information on hiring and recruitment practices and the skills, competencies, and attitudes these employers valued most when hiring recently graduated physicians. The responses showed several differences and/or misperceptions among the views held by the three groups surveyed and suggest that medical educators have not adapted as rapidly as have employers to changes in the health care environment. Academic health centers must broaden their missions and make changes in their own institutional cultures, both to maintain their own viability and to train physicians who have the balance between scientific and technical competency and essential personal characteristics (such as empathy) that the next century's practice will probably demand.

Academic Medical Centers↗

Time to peak serum antibody response to influenza vaccine.

The time to the appearance of a peak serum antibody response to influenza virus vaccine is not clearly defined. We compared the most commonly used time intervals described in the literature--4 and 6 weeks after vaccination. We studied 118 elderly patients from three different geographic sites. The 1992 to 1993 trivalent inactivated influenza virus vaccine containing influenza virus A/Beijing/353/89 (H3N2), influenza virus A/Texas/36/91 (H1N1), and influenza virus B/Panama/45/90 was used. No statistically significant differences were found at the 4- and 6-week intervals after vaccination.

Aged↗

Effects of aging on epinephrine secretion and regional release of epinephrine from the human heart.

In contrast to the sympathetic nervous system, which is activated by aging in at least some sympathetic nervous outflows, epinephrine release from the adrenal medulla appears to be either normal or low in the elderly. Using isotope dilution methodology, we studied the effect of aging on the secretion of epinephrine in 19 men, aged 20-30 yr, and 15 men, aged 60-75 yr. Measurements were made both at rest and during the application of laboratory stressors, as diminished adrenal medullary responsiveness possibly contributes to the impairment of some cardiovascular and metabolic responses to stress described previously in the elderly. Epinephrine secretion at rest was lower in the older men (mean +/- SEM, 0.86 +/- 0.10 nmol/min) than in the younger men (1.45 +/- 0.17 nmol/min; P < 0.05). Due to 20% lower plasma epinephrine clearance in the older men (P < 0.01), the reduction in the plasma concentration of epinephrine (0.37 +/- 0.03 vs. 0.52 +/- 0.06 nmol/L; P = 0.06) was proportionally less than that in epinephrine secretion. In the younger men, epinephrine secretion doubled or tripled during mental stress, isometric exercise, and dynamic exercise. Epinephrine responses to the stressors were reduced in older men, being equivalent to only 44% (P < 0.05), 44% (P = 0.1), and 33% (P = 0.01) of the corresponding responses in the younger men. After uptake from plasma, in some circumstances epinephrine is released from sympathetic nerves as a cotransmitter, where it can augment the release of the major sympathetic transmitter, norepinephrine. We also measured regional extraadrenal release of epinephrine from the heart to test whether the previously described increased release of norepinephrine from the cardiac sympathetic nerves with aging might result from facilitator effects of epinephrine released as a cotransmitter. At rest, epinephrine was released from the heart (9.4 +/- 2.6 pmol/min) in older men only (P < 0.01) despite the fact that adrenal medullary secretion of epinephrine was reduced. Failure of epinephrine and norepinephrine spillover from the heart to increase in parallel in the elderly during the sympathetic excitation accompanying exercise suggested that epinephrine lay outside the sympathetic nerves, perhaps arising from extraneuronal synthesis in the heart. We have not yet tested whether extraneuronal, in contrast to neuronal, epinephrine release in the heart could contribute to the observed higher rates of norepinephrine release in the elderly.

Adult↗

Principles of selection and use of antibacterial agents.

Treatment of infection involves a complex interaction among the infecting organism (susceptibility to the therapeutic agent), host factors (immune function, site of infection, renal and hepatic metabolism), and pharmacokinetics (rate of absorption, distribution and excretion). Successful therapy requires careful consideration of these factors, and unsuccessful treatment should invoke a careful reanalysis of them.

Anti-Bacterial Agents↗

Does asymptomatic bacteriuria predict mortality and does antimicrobial treatment reduce mortality in elderly ambulatory women?

OBJECTIVE: To determine whether asymptomatic bacteriuria in elderly ambulatory women is a marker of increased mortality and, if so, whether it is because of an association with other determinants of mortality or because asymptomatic bacteriuria is itself an independent cause, the removal of which might improve longevity. DESIGN: A cohort study and a controlled clinical trial of the effect of antimicrobial treatment. SETTING: A geriatric center and 21 continuing care retirement communities. PARTICIPANTS: Women without urinary tract catheters. MEASUREMENTS: Urine cultures every 6 months (the same organism at 10(5) colony-forming units or more per mL on two midstream urine specimens defined asymptomatic bacteriuria), comorbidity, and mortality. RESULTS: In the observational study, infected residents (n = 318) were older, and sicker, and had higher mortality (18.7 per 100,000 resident-days) than uninfected residents (n = 1173; 10.1 per 100,000 resident-days). However, in a multivariate Cox analysis, infection was not related to mortality (relative risk, 1.1; P > 0.2), whereas age at entry and self-rated health (score 1 [excellent] to 4 [bad or poor]) were strong predictors. In the clinical trial, mortality in 166 treated residents (13.8 per 100,000 resident-days) was comparable to that of 192 untreated residents (15.1 per 100,000 resident-days); the relative rate was 0.92 (95% CI, 0.57 to 1.47). The cure rates among treated and untreated residents were 82.9% and 15.6%, respectively. CONCLUSION: Urinary tract infection was not an independent risk factor for mortality, and its treatment did not lower the mortality rate. Screening and treatment of asymptomatic bacteriuria in ambulatory elderly women to decrease mortality do not appear warranted.

Aged↗

Assessing diagnostic criteria for active infective endocarditis.

A study was performed to describe agreement among experts on their classification of patients, in the absence of information concerning risk factors, as to the presence of infective endocarditis (IE). The study also assessed the clinical characteristics that enabled the experts to determine that a patient had IE. All patients with a discharge diagnosis of IE were identified prospectively from 54 hospitals in the Delaware Valley over a 3-year period. Patients were part of a case-control study of risk factors for IE. Three infectious disease experts independently reviewed abstracted hospital records and classified each of 151 eligible patients as a definite, probable or possible case, or a probable noncase, both based on clinical judgement and using a modified standard definition. Experts were more likely to classify a patient as a definite case of IE on the basis of clinical judgement than by using the modified standard definition. Agreement between reviewers was 92 to 95% when they were distinguishing only probable non-cases from others. Agreement between reviewers on specific categories was lower (40 to 58%). The number of positive blood cultures was a strong predictor of a patient's being classified as a case, as was the type of infecting organism. It is concluded that experts are willing to make a definitive diagnosis of IE on the basis of blood culture information alone. Further supporting evidence, such as the presence of vegetation on an echocardiogram, is needed when blood culture results are ambiguous.

Adult↗

The teaching and practice of cardiac auscultation during internal medicine and cardiology training. A nationwide survey.

OBJECTIVES: To assess the time and importance given to cardiac auscultation during internal medicine and cardiology training and to evaluate the auscultatory proficiency of medical students and physicians-in-training. STUDY DESIGN: A nationwide survey of internal medicine and cardiology program directors and a multicenter cross-sectional assessment of students' and housestaff's auscultatory proficiency. SETTING: All accredited U.S. internal medicine and cardiology programs and nine university-affiliated internal medicine and cardiology programs. PARTICIPANTS: Four hundred ninety-eight (75.6%) of all 659 directors surveyed; 203 physicians-in-training and 49 third-year medical students. INTERVENTIONS: Directors completed a 23-item questionnaire, and students and trainees were tested on 12 prerecorded cardiac events. MAIN OUTCOME MEASURES: The teaching and proficiency of cardiac auscultation at all levels of training. RESULTS: Directors attributed great importance to cardiac auscultation and thought that more time should be spent teaching it. However, only 27.1% of internal medicine and 37.1% of cardiology programs offered any structured teaching of auscultation (P = 0.02). Programs without teaching were more likely to be large, university affiliated, and located in the northeast. The trainees' accuracy ranged from 0 to 56.2% for cardiology fellows (median, 21.9%) and from 2% to 36.8% for medical residents (median, 19.3%). Residents improved little with year of training and were never better than third-year medical students. CONCLUSIONS: A low emphasis on cardiac auscultation appears to have affected the proficiency of medical trainees. Our study raises concern about the future of this time-honored art and, possibly, other bedside diagnostic skills.

Attitude of Health Personnel↗