Search PubMed⌕ Search

Biomedical subjects

R Platt

Publications and source records attributed to R Platt.

At least 109 records · Page 6Linked to original sources
PubMed1991

Cytidine deaminase activity, C reactive protein, histidine, and erythrocyte sedimentation rate as measures of disease activity in psoriatic arthritis.

Cytidine deaminase activity, C reactive protein, histidine, and erythrocyte sedimentation rate were measured in 36 subjects with psoriatic arthritis of varying disease duration and severity. Although cytidine deaminase activity may provide an integrated measure of synovial inflammation in rheumatoid arthritis, neutrophil accumulation in psoriatic plaques compromises this measure in psoriatic arthritis. Low histidine concentrations confirm that this amino acid provides a non-specific index of synovial inflammation. In psoriatic arthritis high C reactive protein concentrations seem to be associated with extensive joint destruction. In this study the erythrocyte sedimentation rate was found to be the best laboratory guide to clinical disease activity in psoriatic arthritis.

Adult↗
PubMed1990

Association of intravenous lipid emulsion and coagulase-negative staphylococcal bacteremia in neonatal intensive care units.

BACKGROUND AND METHODS: Coagulase-negative staphylococci are now the chief cause of bacteremia in neonatal intensive care units. To investigate potential risk factors for this nosocomial infection, we conducted a case--control study among 882 infants treated in two neonatal intensive care units during 1982. RESULTS: The 38 case patients and 76 controls were similar with respect to 27 indicators of the severity of the underlying illness. In addition, of the 20 potential risk factors for bacteremia that we investigated, only 2 met conventional criteria for causality. Infants with coagulase-negative staphylococcal bacteremia were 5.8 times as likely as controls (95 percent confidence interval, 4.1 to 8.3) to have received intravenous lipid emulsion before the onset of bacteremia. Because the use of lipids was common, 56.6 percent of all of the cases of nosocomial bacteremia could be attributed to lipid administration. Infants with bacteremia were also 3.5 times as likely as controls (95 percent confidence interval, 1.4 to 8.3) to have had a percutaneously inserted central venous catheter (attributable risk, 14.9 percent). The induction time for bacteremia after lipid administration, usually through peripheral catheters, was often less than one day. In contrast, the average induction period for nosocomial bacteremia associated with the use of central catheters, which were rarely used for lipid administration, was at least 5.5 days. Similar analyses of data on an additional 31 neonates treated in 1988 confirmed the strong and apparently independent association of coagulase-negative staphylococcal bacteremia with the intravenous administration of lipids (adjusted odds ratio, 5.3; 95 percent confidence interval, 3.5 to 6.7). CONCLUSIONS: The risk of coagulase-negative staphylococcal bacteremia in infants in neonatal intensive care units can be attributed primarily to the intravenous administration of lipid emulsions. Since lipids are critical for the nutritional support of premature infants, further studies are needed to examine the pathogenesis and prevention of lipid-associated bacteremia.

Catheterization, Central Venous↗
PubMed1990

Perioperative antibiotic prophylaxis for herniorrhaphy and breast surgery.

We assessed the efficacy of perioperative antibiotic prophylaxis for surgery in a randomized, double-blind trial of 1218 patients undergoing herniorrhaphy or surgery involving the breast, including excision of a breast mass, mastectomy, reduction mammoplasty, and axillary-node dissection. The prophylactic regimen was a single dose of cefonicid (1 g intravenously) administered approximately half an hour before surgery. The patients were followed up for four to six weeks after surgery. Blinding was maintained until the last patient completed the follow-up and all diagnoses of infection had been made. The patients who received prophylaxis had 48 percent fewer probable or definite infections than those who did not (Mantel-Haenszel risk ratio, 0.52; 95 percent confidence interval, 0.32 to 0.84; P = 0.01). For patients undergoing a procedure involving the breast, infection occurred in 6.6 percent of the cefonicid recipients (20 of 303) and 12.2 percent of the placebo recipients (37 of 303); for those undergoing herniorrhaphy, infection occurred in 2.3 percent of the cefonicid recipients (7 of 301) and 4.2 percent of the placebo recipients (13 of 311). There were comparable reductions in the numbers of definite wound infections (Mantel-Haenszel risk ratio, 0.49), wounds that drained pus (risk ratio, 0.43), Staphylococcus aureus wound isolates (risk ratio, 0.49), and urinary tract infections (risk ratio, 0.40). There were also comparable reductions in the need for postoperative antibiotic therapy, non-routine visits to a physician for problems involving wound healing, incision and drainage procedures, and readmission because of problems with wound healing. We conclude that perioperative antibiotic prophylaxis with cefonicid is useful for herniorrhaphy and certain types of breast surgery.

Bacterial Infections↗
PubMed1990

Extra hospital stay and antibiotic usage with nosocomial coagulase-negative staphylococcal bacteremia in two neonatal intensive care unit populations.

Coagulase-negative staphylococci were the leading cause of nosocomial bacteremia in the neonatal intensive care units of the Brigham and Women's Hospital and Children's Hospital, Boston, Mass, in 1982. To determine the consequences of these nosocomial bacteremias, a cohort study was conducted in which two comparison subjects were matched with each of 38 bacteremic infants by hospital, birth weight within 100 g, and nearest date of discharge. To adjust for duration of stay in the hospital, it was also required that both comparison subjects have survived and remained in the hospital for as long as the time until bacteremia occurred in the bacteremic infant. The average day of onset of bacteremia was the 20th hospital day. Despite having similar birth weights and comparable severity of underlying illness, bacteremic infants remained in the hospital for an average of 19.8 days longer than the nonbacteremic comparison subjects (77.3 vs 57.5 days). The bacteremic patients received antibiotics for an average of 11.2 more days than the nonbacteremic infants. Vancomycin hydrochloride was given to 20 (52.6%) of the bacteremic patients but only 4 (5.3%) of the comparison patients. All of the comparison subjects and 37 of the 38 infants with bacteremia survived. Thus, nosocomial bacteremia with coagulase-negative staphylococci is a late complication of hospitalization that occurs in infants who are already relatively long-term survivors. This bacteremia appears to be associated with substantially longer hospital stay and antibiotic therapy but little, if any, excess mortality.

Cross Infection↗
PubMed1990

Serum sickness in children after antibiotic exposure: estimates of occurrence and morbidity in a health maintenance organization population.

The computerized outpatient records of the Harvard Community Health Plan, a 230,000-member health maintenance organization, were used to determine the frequency with which serum sickness is recognized in the practice setting after exposure to antibiotics. The medical records of 3,487 children who had been prescribed cefaclor or amoxicillin were searched in December 1986 for coded diagnoses of serum sickness and related conditions. Diagnoses were validated by blinded review of dictated and written office notes. There were 12 cases of serum sickness in 11,523 child-years. During this time, these children were prescribed 13,487 courses of amoxicillin, 5,597 courses of trimethoprim-sulfamethoxazole (TMP-SMZ), 3,553 courses of cefaclor, and 2,325 courses of penicillin V. Serum sickness was considered to be antibiotic-related if it occurred within 20 days of initiation of antibiotic therapy. Five cases were temporally associated with cefaclor, one with both amoxicillin and TMP-SMZ, four with TMP-SMZ alone, and one with penicillin V alone. One case was not associated with any antibiotic exposure. All antibiotic-related cases occurred in children under age 6 years who were treated for otitis media or streptococcal pharyngitis, and most cases began 7-11 days after initiation of antibiotic. All but one of the antibiotic-related cases occurred in children who had relatively heavy lifetime antibiotic exposure. The risk of serum sickness was significantly elevated after cefaclor compared with amoxicillin, even among the most heavily exposed children (relative risk = 14.8, p = 0.01, 95% confidence interval 2.0-352.0). Most cases prompted several physician visits, but none required hospitalization.

Adolescent↗
PubMed1990

Birth weight and length of stay as determinants of nosocomial coagulase-negative staphylococcal bacteremia in neonatal intensive care unit populations: potential for confounding.

Coagulase-negative staphylococci are the most common cause of bacteremia in the neonatal intensive care units of the Brigham and Women's Hospital and the Children's Hospital, Boston, Massachusetts. In 1982, nosocomial bacteremia with coagulase-negative staphylococci occurred in 45 of 882 (5.1%) infants admitted to these units who survived and remained in intensive care for more than 48 hours and were therefore at risk. The overall cumulative incidence (attack rate) of nosocomial bacteremia rose dramatically with decreasing birth weight. The smallest infants, those with birth weights of less than 750 g, experienced an overall risk of nosocomial bacteremia 44.5 times that of infants with birth weights of greater than 2,000 g. A large part of the excess risk for small babies was attributable to their longer hospitalizations. However, after adjustment for length of stay, the smallest infants still suffered a daily rate of bacteremia (incidence density) 5.3 times that of the largest, indicating a considerable residual effect of birth weight on the daily risk of nosocomial coagulase-negative staphylococcal bacteremia. The results were similar in the two nurseries. Thus, there is still a substantially increased intrinsic risk of nosocomial coagulase-negative staphylococcal bacteremia among infants with very low birth weights, even after adjustment for duration of hospitalization, and differences in birth weight can confound comparative studies.

Birth Weight↗
PubMed1989

Prevention of catheter-associated urinary tract infection: a cost-benefit analysis.

A cost-benefit analysis was used to assess four strategies to prevent catheter-associated urinary tract infections in an acute care setting. Routine use of catheters with sealed collection junctions, selective use of these catheters, and oral antibiotic prophylaxis all result in fewer deaths, fewer infections, and lower overall costs than not using any of these. Routine use of sealed junction catheters results in fewer infections and deaths than does selective use. When the cost of a nosocomial urinary tract infection is +500, routine use of sealed junction catheters is also less expensive than selective use in many circumstances. Oral antibiotic prophylaxis would result in the lowest net cost and the fewest deaths and infections, if it were as effective as parenteral prophylaxis, if more than 72% of patients received it, and if important negative factors such as selection of antimicrobial resistance and adverse drug reactions are not considered. When there is no extra cost of sealed junction catheters, their use is less expensive than the oral prophylaxis strategy if the total cost of oral prophylaxis, including the cost of adverse reactions, is greater than +15. If the extra cost of sealed junction catheters is +4 per unit, their use is less expensive than oral prophylaxis when its cost exceeds +35. Prevention of catheter-associated urinary tract infection reduces the overall cost of patient care, even when the prevention itself incurs costs. This analysis supports the routine use of sealed junction catheters in most acute care situations that require indwelling catheter drainage. Currently, we do not recommend routine antibiotic prophylaxis.

Catheters, Indwelling↗
PubMed1988

Safe and cost-effective cleaning of pressure-monitoring transducers.

The CDC category I recommendation for high-level disinfection of pressure-monitoring transducers between uses imposes substantial costs. This practice has not been shown to be useful when disposable transducer domes are used. A prospective, randomized, double-blind study assessed the consequences of wiping transducers with alcohol between uses rather than sterilizing with ethylene oxide. We studied 5,197 transducer courses with disposable domes involving 2,202 patients in intensive care units during 15 months. There was no significant difference between the two treatment regimens in the risk of positive cultures of fluids from monitored lines, of cultures of cannula tips or of a positive blood culture. We conclude that under normal conditions, ie, in the absence of a cluster of transducer-related bacteremias, wiping transducers with alcohol between uses is sufficient when disposable domes are used.

Catheterization↗
PubMed1988

Fifteen-year experience with bloodstream isolates of coagulase-negative staphylococci in neonatal intensive care.

Investigators worldwide, as well as the neonatologists and infection control team at our hospital, have reported that the incidence of coagulase-negative staphylococcal bacteremia in critically ill neonates has increased dramatically in recent years. To investigate these claims, we examined the results of all blood cultures obtained from 1970 to 1984 in our neonatal intensive care unit. Throughout this study period, coagulase-negative staphylococci were prominent blood culture isolates (crude overall incidence of 4.4 positive bacteremia workups per 100 neonates admitted; range, 2.5 to 6.7), representing 26.3 to 69.6% of all positive cultures. There was no significant increase in incidence over time by analysis of linear trend. Detailed analysis of data from 1976 and 1982 (two selected years for which complete information concerning culturing practices and patient characteristics was available) revealed that these observations were not explained by changes in the frequency of blood culturing. In both 1976 and 1982, the probability that a blood culture would grow coagulase-negative staphylococci increased steadily from 2 to 3% shortly after admission to reach a level of about 12% in week 3 of hospitalization, before declining to an intermediate level thereafter. This pattern is more consistent with nosocomial bacteremia than with contamination of blood cultures. Contrary to clinical reports, coagulase-negative staphylococci have been the principal pathogens isolated from blood cultures in our neonatal intensive care unit since at least 1970, with no measurable increase over the subsequent 14 years.

Coagulase↗
PubMed1987

Coagulase-negative staphylococcal bacteremia in the changing neonatal intensive care unit population. Is there an epidemic?

A fivefold increase in the number of cases of nosocomial coagulase-negative staphylococcal bacteremia was investigated in a neonatal intensive care unit between 1975 and 1982. This apparent outbreak was not the result of increased isolation of coagulase-negative staphylococci from blood cultures nor an increased frequency with which blood cultures were obtained. Rather, it was attributable to a dramatic increase in the overall probability that a positive blood culture would be interpreted as "bacteremia" as opposed to a contaminant by both physicians and infection control staff. Specifically, there had been a 62.3% increase in neonatal intensive care unit bed use by very-low-birth-weight (less than 1000-g) infants between 1975 and 1982, and in both years, positive blood cultures were 3.8 times as likely to be perceived as clinically significant if obtained from such tiny infants. The growing number of very-low-birth-weight babies occupying neonatal intensive care unit beds, coupled with the observation that blood cultures positive for coagulase-negative staphylococci are almost four times as likely to be perceived as clinically significant if obtained from extremely premature infants, may account for the reported increase in nosocomial coagulase-negative staphylococcal bacteremia.

Boston↗
PubMed1987

Adverse consequences of asymptomatic urinary tract infections in adults.

Asymptomatic urinary tract infection (UTI) in adults can be associated with serious sequelae. During pregnancy, it causes pyelonephritis and low-birth-weight deliveries, both of which can be reduced in frequency by treatment of the bacteriuria. This asymptomatic infection is also associated with an increased risk of perinatal fetal death; no beneficial effect of therapy has been observed for this condition, however. Asymptomatic UTI has been associated with excess mortality in adult women in a general community setting and in adults of both sexes in a nursing home. To date, there has been no adequate test of treatment of asymptomatic UTI in these groups. UTIs that result from short-term, indwelling bladder catheterization in acute-care hospitals are also associated with a marked increase (relative odds equal to 2.8) in the risk of dying during the hospitalization. A randomized trial of preventive measures that reduced the risk of catheter-associated UTI demonstrated a decrease in mortality commensurate with the lesser risk of infection. These data suggest that asymptomatic UTI may increase the risk of death under certain circumstances. Additional studies are indicated to confirm the phenomenon, to identify high-risk persons, and to determine whether prevention and/or treatment of asymptomatic UTI reduces these effects.

Adult↗
PubMed1987

Confound it!

Explore the source record for details and available documents.

Cross Infection↗
PubMed1986

Risk factors for nosocomial urinary tract infection.

In a prospective study carried out in June 1979-April 1981, 134 of 1,458 adult inpatients at New England Deaconess Hospital, Boston, Massachusetts, acquired 136 urinary tract infections during 1,474 indwelling bladder catheterizations. Multiple logistic regression analysis identified nine factors that were significantly associated with acquisition of infection: duration of catheterization, lack of systemic antibiotic during short catheter courses, lack of urinemeter drainage, female sex, diabetes mellitus, microbial colonization of the drainage bag, serum creatinine greater than 2 mg/dl at the time of catheterization, the reason for catheterization, and the use of catheters with sealed collection junctions when no antibiotic was administered. When potential risk factors were considered individually, without adjusting for the influence of other factors, infection was also significantly associated with 11 other factors, including several that have been previously reported as risk factors for catheter-associated urinary tract infections; however, these associations were no longer significant after adjustment for one or more of the nine factors noted above. These findings suggest approaches to surveillance, prevention, and research activities. They also strongly support the widely-held but poorly documented belief that persons with diabetes are more susceptible to urinary tract infection than are persons without diabetes.

Adult↗
PubMed1986

Nonresponsiveness to hepatitis B vaccine in health care workers. Results of revaccination and genetic typings.

Twenty-eight health care workers who had a poor antibody response when initially vaccinated with hepatitis B vaccine were revaccinated with three additional 20-microgram doses. Eight of the twenty nonresponders, who had levels of antibody to hepatitis B surface antigen (anti-HBs) of less than 8 estimated radioimmunoassay (RIA) units, and all 8 of the hyporesponders, who had anti-HBs levels of 8 or 16 RIA units, attained anti-HBs levels of 36 RIA units or more after revaccination. Tests for HLA-A, B, C, and DR; for complement proteins C2, C4A, C4B, and BF; and for the erythrocyte enzyme glyoxalase I were done in 17 nonresponders and 3 hyporesponders. Nine (45%) had HLA-DR7 and 8 (40%) had HLA-DR3, compared with an expected rate of 23% in the general population. At least one of two extended haplotypes (B44, DR7, FC31 or B8, DR3, SCO1) were detected in 6 of the 9 who did not respond to revaccination, compared with 2 of 11 who responded to a second course of vaccine. Poor responders to vaccine may benefit from revaccination, and genetic factors may modulate the immune response to vaccination.

Adult↗
PubMed1985

Medically useful criteria for analytic performance of laboratory tests.

To establish medically useful guidelines for analytic precision of commonly used clinical laboratory procedures, the authors conducted a mail survey of physicians selected randomly from national lists of specialists. They were asked to review, briefly, outlined clinical problems and select the change in test results that would alter their diagnosis or treatment or prompt further assessment of the patient's condition. The responses were used to calculate goals for laboratory precision that are sufficient to meet the present requirements of the average physician. The medically useful limits were compared with existing performance of laboratories as reported in national proficiency surveys and regional quality control programs. Almost all the common laboratory procedures they studied are being assayed at a precision level adequate for the perceived needs. The authors suggest that, for the more common constituents, further progress in clinical laboratory testing will depend on factors other than the improvement of analytic precision.

Attitude of Health Personnel↗