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Biomedical subjects

R Platt

Publications and source records attributed to R Platt.

At least 127 records · Page 7Linked to original sources
PubMed1985

Isolated antibody to hepatitis B surface antigen and response to hepatitis B vaccination.

To determine the need for immunization of health workers with antibody to hepatitis B surface antigen (anti-HBs) as their only serologic marker of previous hepatitis B exposure, we studied the level, persistence, and immunologic specificity of isolated anti-HBs in 46 persons identified during screening for hepatitis B vaccine. We rescreened these persons 1 year later, administered a single dose of hepatitis B vaccine, and determined the anti-HBs level at 1, 2, and 8 weeks after vaccination. Isolated anti-HBs levels were low and antibody did not persist; 22 subjects tested had lost detectable anti-HBs within 19 months even though immunologic specificity was shown in vitro in 34. Anamnestic responses suggesting previous exposure and immunity were seen in only 10 subjects; 5 of these subjects had moderate-level, persistent anti-HBs. Although some persons with naturally acquired, isolated anti-HBs may be protected from hepatitis B, the immunologic specificity and protective value of anti-HBs, especially when levels are low, remain questionable.

Antibody Specificity↗
PubMed1984

Lack of utility of routine screening tests for early detection of peritonitis in patients requiring intermittent peritoneal dialysis.

A prospective study was undertaken to examine the clinical presentation of peritonitis in patients maintained on intermittent peritoneal dialysis and to determine the value of qualitative and quantitative dialysate cultures, gram stain, neutrophil counts, and a semi-quantitative leukocyte test strip for case detection. Seven cases of peritonitis developed among 30 patients who underwent 553 dialyses. In most cases, neutrophil counts, cultures, and leukocyte test strip determinations were done within 48 hours prior to the clinical onset of peritonitis and in all instances failed to provide clues for incipient infection. Peritonitis was associated with a dialysate neutrophil count of greater than 500/mm3 and leukocyte test strips were highly sensitive and specific for the detection of this quantity of neutrophils. A total of 16 dialysate cultures was positive in asymptomatic patients who did not have peritonitis. None of these patients subsequently developed peritonitis with the same organism. Dialysate gram stains, cultures, neutrophil counts or leukocyte test strips did not provide an early diagnosis of peritonitis and their use in the absence of symptoms is therefore not recommended.

Diagnostic Tests, Routine↗
PubMed1984

A multivariate analysis of risk factors for hepatitis B virus infection among hospital employees screened for vaccination.

Previous studies of risk factors for hepatitis B virus infection among hospital employees have been based on surveys in single institutions or have been analyzed with univariate techniques. From November 1980 through August 1981, the authors performed a multi-institutional seroepidemiologic survey of hospital employees screened for entrance into a hepatitis B vaccine trial who represented groups at high risk for hepatitis B infection. Using a logistic regression model for the analysis of risk factors, the investigators determined the relative odds and 95% confidence intervals for risk of hepatitis B infection to be as follows: race (nonwhite/white: 3.4; 2.4-4.8) (p less than 0.001); history of acute viral hepatitis of an unspecified type (3.6; 2.2-5.9) (p less than 0.001); and employment at hospitals 1 through 5 as compared with hospital 6 (1.8; 1.1-2.9) (p = 0.015). In addition, certain job categories and the duration of employment within some of these categories were associated with increasing risk for hepatitis B infection over time. Laboratory workers (1.4; 1.2-1.7), surgical staff (1.2; 1.1-1.4), and medical staff (1.3; 1.1-1.5) had significant (p less than 0.05) increased risk of prior infection with longer duration of employment. Such time-job interaction was not demonstrable for nursing staff, anesthesiology staff, dental personnel, pathology staff, or ancillary personnel. The logistic regression model also shows that the highest gradient of risk for laboratory workers, surgeons, and medical staff occurs during the first five years of employment. An effective preventive strategy, such as the use of hepatitis B vaccine, should be targeted for these groups at the time of initial employment.

Adult↗
PubMed1984

Hepatitis B vaccine in health care personnel: safety, immunogenicity, and indicators of efficacy.

In a double-blind trial, we randomly assigned 1330 high-risk health care personnel to receive three 20-micrograms doses of hepatitis B vaccine or placebo. Among vaccine recipients 58% responded within 1 month and 97% within 9 months; there was no difference in immune response to the vaccine between men and women. Efficacy was evaluated after a mean follow-up of only 13.2 months, just before the vaccine was released commercially. Five hepatitis B infections were identified in placebo recipients and one in a vaccine recipient. Although the number of infections was too small to allow confident conclusions about protective efficacy of the vaccine, we saw a 67% reduction in the need for hepatitis B immune globulin after accidental hepatitis B inoculation in the vaccine group (relative risk, 5.08; 95% confidence intervals, 1.3 to 19.9). Minor side effects occurred with equal frequency after vaccine (28.7%) and placebo (27.2%) injections; no participant had a severe adverse reaction. Vaccination with the 20-micrograms hepatitis B vaccine was highly immunogenic and safe in health care workers.

Adult↗
PubMed1984

Antibiotic prophylaxis for cardiovascular surgery. Efficacy with coronary artery bypass.

Two hundred twenty patients were randomly assigned to receive either ceforanide or cephalothin as perioperative antibiotic prophylaxis during cardiovascular surgery. More infections were seen among cephalothin recipients (8 deep, 32 total) than among ceforanide recipients (1 deep, 17 total). Among patients who had only coronary artery bypass grafting, more cephalothin recipients had infection than did ceforanide recipients (19 of 82 as opposed to 7 of 83; p = 0.001; relative risk, 2.7; 95% confidence interval, 1.22 to 6.18). The difference between the two regimens was attributable to fewer blood, wound, and urinary tract infections. Among patients who had other procedures, there was no difference in the efficacy of the two regimens. Cephalothin recipients who developed wound or blood stream infections had lower antibiotic levels in their atrial appendages than recipients not developing such infections (p = 0.02). If one assumes that cephalothin does not increase the risk of infection, then these data show that antibiotic prophylaxis prevents infection after coronary artery bypass surgery, and, in the dosages used, that ceforanide is superior to cephalothin.

Cefamandole↗
PubMed1983

Risk of acquiring gonorrhea and prevalence of abnormal adnexal findings among women recently exposed to gonorrhea.

We determined the conditions of 26 women who had recently been exposed to Neisseria gonorrhoeae. Infection was more common among women with more than one exposure (13/14) than among those with one exposure (6/12). Gonococcal infection was significantly associated with the presence of findings on physical examination suggestive of upper genital tract inflammation. Nine of 19 infected women had such findings; no uninfected women did. Among infected women, the prevalence of abnormal physical findings was 47% +/- 23% (95% confidence interval). These findings suggest that upper genital tract involvement is a common early complication of gonococcal infection.

Female↗
PubMed1983

Cost containment--another view.

There is an emerging public consensus that in a slowly growing economy, the continuing rise in the nation's health-care costs must be moderated. Ginzberg has suggested that we can and must do this without reducing the quality of care we provide and without major changes in the structure or governance of our health-care-delivery system. He implies that we can readily identify and eliminate substantial numbers of useless health-care services. Such an approach to cost containment is almost certain to fail. A successful cost-containment program will include some or all of the following elements: caps on public health expenditures and implicit limits on the quality and accessibility of health care to be provided at public expense, much tighter government regulation of private health-care expenditures, control of the physician supply, and modification of the fee-for-service reimbursement system for physicians and hospitals. Until our society is prepared to accept these kinds of structural changes and their adverse impact, to some degree, on the quality and accessibility of health services, effective cost containment will not occur. Are we ready for these kinds of changes? Should we be? Perhaps we ought to be less concerned about cost containment and more prepared to spend 12 or 13 per cent of the gross national product on health care by 1990. What we should not do is pretend that painless cost containment is an achievable goal.

Ambulatory Care↗
PubMed1983

Quantitative definition of bacteriuria.

Quantitative criteria distinguish bacterial infection (or colonization) of the urine from contamination. These criteria depend on the fact that the density of bacteria in infected urine is usually several orders of magnitude higher than the density of bacteria in contaminated urine. Most research on quantitative definitions of infection has concerned Gram-negative rod infections in women. For asymptomatic bacteriuria, the most prevalent urinary tract infection, and for pyelonephritis, a criterion of 1 X 10(5) cfu/ml provides optimal separation of infection from contamination of voided urine. For acute dysuria and frequency, recent evidence supports the use of a colony count of 1 X 10(2) cfu/ml bacteria as the most useful criterion. For the diagnosis of catheter-associated urinary tract infection, the criterion of 1 X 10(5) cfu/ml has been used most commonly, although a lower threshold may be appropriate. Additional investigation is required to determine the most appropriate quantitative definition of infection in this and several other circumstances.

Bacteria↗
PubMed1983

Reduction of mortality associated with nosocomial urinary tract infection.

A randomised controlled trial was conducted to assess whether bladder catheters with preconnected sealed junctions were associated with a lower risk of urinary-tract infection than were catheters without such junctions, and to determine whether prevention of catheter-associated infection would be accompanied by a reduction of mortality. Among those not taking systemic antibiotics, patients assigned sealed junction catheters had fewer infections and deaths. Before they received antibiotics, the risk of infection among those assigned unsealed catheters was 2.7 times that of patients assigned sealed catheters (95% confidence interval=1.3-5 . 4, p=0 . 007). Among the 220 patients who received no antibiotics, 14% (15/108) of those assigned unsealed catheters and 4% (4/112) of those assigned sealed catheters died. Stratification by important risk factors for mortality yielded an adjusted risk ratio for death of 3.4 (95% CI=1.1-10.7, p=0.03). Among patients who received systemic antibiotic the use of sealed catheters did not affect infection rates (RR=0.9, 95% CI=0.5-1.5, p=0.68) or deaths (RR=1.2, 95% CI=0.6-2.2, p=0.62). These data indicate how the rates of infection and mortality can be reduced in hospital. Since the degree of reduction in mortality corresponded with the degree of reduction of infection, measures to prevent catheter-associated nosocomial urinary tract infection should be implemented.

Anti-Bacterial Agents↗
PubMed1982

Mortality associated with nosocomial urinary-tract infection.

In a prospective study, 131 of 1458 patients acquired 136 urinary-tract infections (defined as greater than 10(5) colony-forming units per milliliter) during 1474 indwelling bladder catheterizations. Seventy-six patients (25 infected and 51 noninfected) died during hospitalization; death rates were 19 per cent in infected patients and 4 per cent in noninfected patients. Multiple logistic regression analysis demonstrated that seven of 21 prospectively monitored variables were associated with mortality among the catheterized patients. The adjusted odds ratio for mortality between those who acquired infection and those who did not was 2.8 (95 per cent confidence limits, 1.5 to 5.1). The acquisition of infection as not associated with the severity of underlying disease; among patients who died, infections occurred in 38 per cent of those classified as having nonfatal underlying disease (15 of 39) and in 27 per cent of those classified as having fatal disease (10 of 37). Twelve deaths may have been caused by acquired urinary-tract infections. Two patients had urinary-tract pathogens in premortem blood cultures. Another 10 died with clinical pictures compatible with serious infection, but no diagnostic cultures were performed. We conclude that the acquisition of urinary-tract infection during indwelling bladder catheterization is associated with nearly a threefold increase in mortality among hospitalized patients, but the reason for this association is not yet clear.

Catheters, Indwelling↗
PubMed1982

Staphylococcus aureus bacteremia in diabetic patients. Endocarditis and mortality.

The presentation and course of Staphylococcus aureus bacteremia in 27 diabetic patients (18 insulin-dependent) were compared with those in 34 nondiabetic patients. The groups were comparable in age, proportion with pre-existing cardiac valvular disease, community-acquired bacteremia, fever, and leukocytosis. Endocarditis (vegetation or new regurgitant murmur) was present in eight (30 percent) diabetics and four (12 percent) nondiabetics (p = 0.16). A primary focus of infection was present in 67 percent of diabetics and 65 percent of nondiabetics. Among those with a focus, six of 18 diabetics and none of 22 nondiabetics had endocarditis (p less than 0.005). Fifteen of 54 (28 percent) patients who received appropriate antibiotic therapy died. After stratificaton for underlying illness, there was no mortality difference between those with and without endocarditis (three endocarditis deaths versus 1.78 expected), or between those with and without diabetes (four diabetic deaths versus 4.8 expected). Diabetics with staphylococcal bacteremia were more likely than nondiabetics to have endocarditis in the presence of a primary focus. They had no increase in mortality.

Adult↗
PubMed1981

Moxalactam therapy of infections caused by cephalothin-resistant bacteria: influence of serum inhibitory activity on clinical response and acquisition of antibiotic resistance during therapy.

Thirty patients infected predominantly by Serratia marcescens and Pseudomonas aeruginosa were treated in an open trial with moxalactam, a broad-spectrum beta-lactam antibiotic. Twenty-three (76%) had a satisfactory microbiological or clinical response. Among 25 patients for whom serum inhibitory concentrations were measured, those with favorable microbiological responses had significantly higher values than those with poor responses (reciprocal geometric mean concentrations, 49 versus 4.9; P less than 0.01). A serum inhibitory concentration of greater than 1:8 correlated significantly with a favorable outcome (17 of 18 versus 2 of 7 responses; P less than 0.01). Although the overall clinical efficacy of moxalactam was good, resistant organisms of species identical to those of the original infecting isolates were recovered during therapy in seven cases, including five caused by Pseudomonas organisms and two caused by Serratia organisms.

Adult↗
PubMed1981

Intralaboratory analytic precision as estimated from two distinct programs from the College of American Pathologists.

Results for serum sodium and calcium analysis reported to the College of American Pathologists' (CAP) Basic and Comprehensive Chemistry Surveys and to the CAP Quality Assurance Service Program showed good consistency in estimates of intralaboratory analytic precision. The results compare favorably with those obtained in independent studies and indicate that CAP data sources can be used as reliable indices of analytic performance in the clinical laboratory.

Blood Chemical Analysis↗
PubMed1980

Infection with Mycoplasma hominis in postpartum fever.

A follow-up of 535 patients after vaginal delivery showed that 9% had a fever of 37.7 degrees C or greater, and 2% had a fever of 38 degrees C or more, on two days. The commonest cause of both categories of fever was Mycoplasma hominis infection as defined by a fourfold or greater rise in mycoplasmacidal antibody titre. Among women for whom sera were available this agent caused 50% (14/28) of all fevers and 71% (5/7) of the higher fevers. Absence or low titre (< 1:8) of antibody against M. hominis was the strongest single predictor of otherwise unexplained fever (16/40 patients with low antibody titre were febrile vs 7/50 with high antibody titre, p < 0.01). Among women with absent or low antibody titres, both rise in titre of antibody to this organism and lochial colonisation by it were significantly associated with fever (p < 0.001, p < 0.025, respectively). Standard microbiological and clinical techniques identified probable causes in only 18% (5/28) of all fevers and 29% (2/7) of higher fevers. Patients who had postpartum infection caused by M. hominis remained in hospital 31% longer than the non-infected patients (4.57 vs 3.49 days, p < 0.001). Low antibody to and lochial colonisation with M. hominis occurred together in 17% of patients, who accounted for 71% of all higher fevers. Since these risk factors for postpartum fever can be identified before delivery, prophylactic measures applied selectively to women with these risk factors may prevent a large proportion of postpartum fevers and the excess hospital stay associated with them.

Adult↗