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E Abrutyn

Publications and source records attributed to E Abrutyn.

At least 19 recordsLinked to original sources

Immune response to influenza vaccination in a large healthy elderly population.

Elderly individuals not only demonstrate a greater risk of morbidity and mortality from influenza than the young, but also have greater difficulty mounting a protective response to influenza vaccine. The mechanism of the decreased efficacy of influenza vaccination in the elderly is not well understood. The present study was designed to assess the interaction between cell-mediated and humoral immune responses to influenza vaccine in a large population (n = 233) of healthy elderly individuals (mean age = 80.7) living in six continuing care retirement communities (CCRCs). While influenza vaccination resulted in significant increases in the mean anti-influenza antibody titres and mean proliferative responses of peripheral blood mononuclear cells to purified subvirion trivalent influenza vaccine one month after vaccination, only 48.9% and 30.0% of subjects had intact humoral and cell-mediated immune responses, respectively. No association was observed between intact cell-mediated and humoral responses: 14.7% of subjects had an intact cell-mediated, but not humoral response, and 32.6% of subjects had an intact humoral, but not cell-mediated response. However, IFNgamma production was significantly correlated with both antibody and cell-mediated responses to influenza vaccination, a finding not previously reported in the elderly. These results indicate that there is considerable heterogeneity among immune responses of the elderly to influenza vaccination. This heterogeneity needs to be a major consideration in evaluation of new vaccine preparations.

Aged

Dental and cardiac risk factors for infective endocarditis. A population-based, case-control study.

BACKGROUND: Although antibiotic prophylaxis against infective endocarditis is recommended, the true risk factors for infective endocarditis are unclear. OBJECTIVE: To quantitate the risk for endocarditis from dental treatment and cardiac abnormalities. DESIGN: Population-based, case-control study. SETTING: 54 hospitals in the Philadelphia area. PATIENTS: Persons with community-acquired infective endocarditis not associated with intravenous drug use were compared with community residents, matched by age, sex, and neighborhood of residence. MEASUREMENTS: Information on demographic characteristics, host risk factors, and dental treatment was obtained from structured telephone interviews, dental records, and medical records. RESULTS: During the preceding 3 months, dental treatment was no more frequent among case-patients than controls (adjusted odds ratio, 0.8 [95% CI, 0.4 to 1.5]). Of 273 case-patients, 104 (38%) knew of previous cardiac lesions compared with 17 controls (6%) (adjusted odds ratio, 16.7 [CI, 7.4 to 37.4]). Case-patients more often had a history of mitral valve prolapse (adjusted odds ratio, 19.4 [CI, 6.4 to 58.4]), congenital heart disease (adjusted odds ratio, 6.7 [CI, 2.3 to 19.4]), cardiac valvular surgery (adjusted odds ratio, 74.6 [CI, 12.5 to 447]), rheumatic fever (adjusted odds ratio, 13.4 [CI, 4.5 to 39.5]), and heart murmur without other known cardiac abnormalities (adjusted odds ratio, 4.2 [CI, 2.0 to 8.9]). Among case-patients with known cardiac lesions--the target of prophylaxis--dental therapy was significantly (P = 0.03) less common than among controls (adjusted odds ratio, 0.2 [CI, 0.04 to 0.7] over 3 months). Few participants received prophylactic antibiotics. CONCLUSIONS: Dental treatment does not seem to be a risk factor for infective endocarditis, even in patients with valvular abnormalities, but cardiac valvular abnormalities are strong risk factors. Few cases of infective endocarditis would be preventable with antibiotic prophylaxis, even with 100% effectiveness assumed. Current policies for prophylaxis should be reconsidered.

Adolescent

Cytokine production after influenza vaccination in a healthy elderly population.

Influenza vaccination is less efficacious in the elderly than in the young. To characterize this age-related decrease in immune response to influenza vaccination, antibody and cell-mediated responses to influenza vaccine were assessed before immunization and 4 weeks after vaccination of a population of 270 healthy elderly individuals (mean age: 80.2 years) living in eight local continuing care retirement communities (CCRCs) and 30 young individuals (mean age: 27.8 years). The antibody titres produced against all three influenza strains increased significantly after vaccination in both the young and elderly (p < 0.0005); however, the young demonstrated significantly higher titres to all three strains than did the elderly (p < 0.03). Peripheral blood mononuclear cells (PBMC) cultured with influenza vaccine demonstrated significantly increased proliferation (elderly: p < 0.00005; young: p < 0.001) after vaccination, with proliferative responses in the young significantly higher than the elderly both before (p < 0.04) and after (p < 0.0005) vaccination. Similarly, IFN gamma production in these PBMC cultures increased significantly pre- to postvaccination in both young and elderly (young: p < 0.006; elderly: p < 0.00005), but the young produced more than the elderly both pre- and postvaccination (p < 0.0001). Following vaccination, PBMC production of IL-10 was higher in the young than in the elderly (p < 0.0015), while IL-6 production was comparable in both young and elderly individuals. Greater than 13% of the elderly population did not produce detectable IL-6, IL-10, or IFN gamma either before or after vaccination. The data show that the decreased cell-mediated and humoral responses to influenza vaccination of this healthy elderly population are accompanied by the production of lower levels of cytokines. A unique finding in this population of 270 healthy elderly was the association between a TH0 cytokine profile and intact immune responses to influenza vaccine. A similar relationship was not seen in the young.

Adult

Urinary tract infection in older adults.

Urinary tract infection is common among older adults, although most individuals are asymptomatic. The prevalence of bacteriuria varies significantly with living situation and functional status. Asymptomatic bacteriuria is a benign condition and is not an independent risk factor for mortality in older adults. Treatment of asymptomatic bacteriuria generally is not indicated, but symptomatic urinary tract infection of the lower or upper tract dictates antibiotic therapy.

Age Factors

The age-associated decline in immune function of healthy individuals is not related to changes in plasma concentrations of beta-carotene, retinol, alpha-tocopherol or zinc.

The decline in the lymphoproliferative response to mitogenic stimuli shows marked heterogeneity in elderly individuals. Adequate nutriture is required for optimal immune function, yet nutritional status may be compromised in the elderly. To address whether this variation in the proliferative response of elderly individuals is related to their nutritional status, we studied 61 elderly (80.5 +/- 5.7 year-old) and 27 young (27.3 +/- 3.8 year-old) individuals participating in an ongoing assessment of their immune response to influenza vaccine. Ambulatory elderly individuals were recruited from five different retirement communities and were in good health upon enrollment in the study. Thirty-three percent of young and 54% of elderly subjects reported consuming micronutrient supplements daily during the study. Plasma and peripheral blood mononuclear cells (PBMC) were isolated from fasting individuals twice, 4-6 weeks apart. At both times, proliferative responses to the mitogens phytohemagglutinin (PHA), concanavalin A (Con A), and pokeweed mitogen (PWM) were significantly lower (P < 0.004) in the elderly compared to the young. However, at both times, elderly participants had plasma concentrations of beta-carotene, retinol, alpha-tocopherol and zinc that were either significantly greater than, or equal to, those of young subjects. No significant correlations between plasma concentrations of beta-carotene, retinol, alpha-tocopherol and zinc and level of proliferative responses to each stimuli were observed in elderly individuals at either time. Thus, the heterogeneity in the proliferative response to mitogenic stimuli exhibited by a healthy elderly population cannot be attributed to differences in these nutritional parameters.

Adult

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

Immunoprophylaxis against klebsiella and pseudomonas aeruginosa infections. The Federal Hyperimmune Immunoglobulin Trial Study Group.

To determine if passive immunization could decrease the incidence or severity of Klebsiella and Pseudomonas aeruginosa infections, patients admitted to intensive care units of 16 Department of Veterans Affairs and Department of Defense hospitals were randomized to receive either 100 mg/kg intravenous hyperimmune globulin (IVIG), derived from donors immunized with a 24-valent Klebsiella capsular polysaccharide plus an 8-valent P. aeruginosa O-polysaccharide-toxin A conjugate vaccine, or an albumin placebo. The overall incidence and severity of vaccine-specific Klebsiella plus Pseudomonas infections were not significantly different between the groups receiving albumin and IVIG. There was some evidence that IVIG may decrease the incidence (2.7% albumin vs. 1.2% IVIG) and severity (1.0% vs. 0.3%) of vaccine-specific Klebsiella infections, but these reductions were not statistically significant. The trial was stopped because it was statistically unlikely that IVIG would be protective against Pseudomonas infections at the dosage being used. Patients receiving IVIG had more adverse reactions (14.4% vs. 9.2%).

Antibodies, Bacterial

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

Antimicrobial resistance patterns in long term geriatric care. Implications for drug therapy.

There is a high prevalence of bacterial infections in long term care facilities (4.4 to 16.2%). This, together with the fact that antimicrobial resistance is a big concern in current medical practice, makes infection control so important in nursing home care. This article covers the mechanisms of antibacterial resistance and focuses on 4 major antibacterial-resistant bacteria. Vancomycin is the treatment of choice for methicillin-resistant Staphylococcus aureus (MRSA). Colonisation with MRSA is not uncommon in nursing homes and eradication is probably not necessary. Any clinically important enterococcal infection should be tested for high-level resistance. An infectious disease consultation should be sought for vancomycin-resistant enterococcal infections. Gram-negative bacilli have developed multi-resistance. Susceptibility testing can identify the most appropriate therapy. Multiresistance should also be considered when treating Streptococcus pneumoniae. Overall, handwashing is highly recommended. Barrier precautions, minimising hospitalisations and avoiding unnecessary personnel rotation can reduce the chance of resistance spread.

Aged

Optimal treatment of urinary tract infections in elderly patients.

Elderly patients are at high risk for urinary tract infection (UTI). Infections of the urinary tract may be classified as asymptomatic bacteriuria, uncomplicated cystitis, uncomplicated pyelonephritis or complicated UTI. The micro-organisms responsible for causing UTI are largely predictable and dictate therapy when indicated. UTIs may be diagnosed by both nonculture and culture techniques. Asymptomatic bacteriuria, though quite common in the elderly, should rarely be treated. Treatment of symptomatic uncomplicated and complicated UTIs is largely dictated by the known or expected pathogen(s) and classification of the infection. Additional features affecting the treatment of UTI in the elderly include allergies, adverse reactions to therapy, drug interactions and modification for renal insufficiency.

Aged

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

Developing policies and guidelines.

Practice guidelines are proliferating in the era of managed care. Hospital epidemiologists frequently are asked to author guidelines of infection control. The greatest challenge in the process is not writing the guidelines but implementing them. This article offers practical advice on which topic to select and on how to develop and implement guidelines.

Cost Control

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

Pathogens resistant to antimicrobial agents. Epidemiology, molecular mechanisms, and clinical management.

The emergence of resistance to antimicrobial agents continues to be a major problem among both nosocomial and community-acquired pathogens. Bacteria employ a variety of strategies to avoid the inhibitory effects of antibiotic agents, and have evolved highly efficient means for the dissemination of resistance traits. The result has been the emergence of multidrug-resistant pathogens such as penicillin-resistant pneumococci, vancomycin-resistant enterococci, methicillin-resistant staphylococci, as well as a variety of multiresistant gram-negative organisms. Control of antibiotic-resistant pathogens will provide a major challenge for both the medical community and society in general. The implication of a failure to meet this challenge is the eventual arrival of the "post antibiotic era."

Bacteria

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