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L Leibovici

Publications and source records attributed to L Leibovici.

At least 19 recordsLinked to original sources
PubMed1992

Patterns of multiple resistance to antibiotics in gram-negative bacteria demonstrated by factor analysis.

Principal component analysis was used to demonstrate the main associations between patterns of resistance to antibiotic drugs in 670 gram-negative bacteria consecutively isolated from blood cultures over a period of two years. Six factors were derived, which accounted for 84% of the total variance of the original matrix. Each factor represented an association between resistance to certain antibiotics as follows: factor 1: aztreonam, third generation cephalosporins and aminoglycosides; factor 2: first and second generation cephalosporins; factor 3: tetracycline and chloramphenicol; factor 4: ampicillin and ureidopenicillins; factor 5: trimethoprim/sulfamethoxazole; factor 6: fluoroquinolones. On two-way analysis of variance the difference in the factor scores was significant between bacteria for all factors except factor 5. The difference in factor scores between community and hospital acquired strains was significant only for factors 1, 2 and 6. Only the score of factor 6 showed a clear trend to increase with time during the two-year study period. Patients who were treated with antibiotics prior to bacteremia had higher scores for all factors, the difference being most marked in patients treated with fluoroquinolones. Factor analysis can be used to describe phenotypic associations between resistance to antibiotics, and the factor score used to compare groups of isolates and to demonstrate temporal and other trends.

Ampicillin↗
PubMed1992

Bacteremia and fungemia of unknown origin in adults.

Two hundred fifteen (23%) of 955 episodes of bacteremia (defined as including fungemia) detected in adult patients during 2 years were of unknown origin. Sixty-six percent of episodes of unknown origin were hospital acquired. The median age of patients with bacteremia of unknown origin was 65 years, and their most common underlying disorders were solid malignancy (28% of patients) and diabetes mellitus (18%). Only three factors were associated with bacteremia of unknown origin (as opposed to episodes with a known source): peripheral venous catheterization, hemodialysis, and plasmapheresis. Gram-negative bacteria were isolated from the blood in 62% of episodes of unknown origin; 10% of episodes were polymicrobial. Staphylococci were isolated from 67% of patients undergoing hemodialysis and from 37% of those with diabetes; Pseudomonas species from 15% of patients with hospital-acquired episodes; and Candida species from 21% of patients with a central venous catheter. Fifteen percent of episodes in cancer patients were polymicrobial. Empirical antibiotic treatment was inappropriate in 49% of episodes of unknown origin and in 35% of episodes with a known source (P less than .001). Death rates were 44% and 25% in episodes of unknown and known origin, respectively. An unknown source of bacteremia was independently associated with a fatal outcome.

Adolescent↗
PubMed1992

Risk factors for mortality due to bacteremia and fungemia in childhood.

To define risk factors for mortality due to bacteremia and fungemia of childhood, 242 episodes (for which the mortality rate was 19%) were studied prospectively by univariate and multivariate analyses. The mortality rate was higher in neonates (23%) and in individuals 10-18 years old (26%) than in infants and young children (10%-16%). The mortality rate was 29% for children who had neutropenia, 29% for those who had received therapy with steroids, 26% for those who had received antibiotics, and 75% for those who were in septic shock. The fatality rates for polymicrobial bacteremia (40%), recurrent bacteremia (67%), and hospital-acquired bacteremia (28%) were higher than those for other types of bacteremia; the fatality rate was related to inappropriate empiric antibiotic treatment or to the specific organism isolated (mortality rates associated with the latter ranged from 0 to 60%). Seven variables that independently and significantly affected mortality were defined with use of multivariate logistic regression analysis: septic shock (odds ratio [OR], 26.4); polymicrobial (OR, 5.4), recurrent (OR, 4.5), or hospital-acquired (OR, 4.3) bacteremia; candidemia (OR, 3.6); inappropriate antibiotic treatment (OR, 2.4); and neutropenia (OR, 2.3). These variables should be considered for adequate management of bacteremic patients who are at high risk for death.

Adolescent↗
PubMed1992

Patients at risk for inappropriate antibiotic treatment of bacteraemia.

In order to define patients at high risk for inappropriate antibiotic treatment of bacteraemia, we compared 682 bacteraemic patients, treated with an antibiotic drug to which the infecting micro-organism was susceptible, with 419 patients who were inappropriately treated. On a multivariate logistic regression analysis including only clinical variables, four factors were found to be both significantly and independently associated with inappropriate antibiotic treatment: hospital-acquired bacteraemia (odds-ratio (OR) of 1.9), antibiotic treatment in the month prior to the bacteraemia (OR 1.9), residence in a nursing home (OR 1.8), and the presence of a central line (OR 1.7). A second model, including bacteriological data, showed four micro-organisms to be independently associated with inappropriate antibiotic treatment: Candida sp. (OR 14.2), Acinetobacter sp. (OR 5.0), Enterococcus sp. (OR 3.6) and Pseudomonas sp. (OR 2.2). In this model, only two clinical features were included: hospital-acquired infection and previous antibiotic treatment. Special efforts should be made to improve empirical antibiotic treatment in the groups defined above, and to facilitate early laboratory diagnosis of the micro-organisms associated with inappropriate treatment.

Anti-Bacterial Agents↗
PubMed1992

Toward improved empiric management of moderate to severe urinary tract infections.

BACKGROUND: Guidelines to show whether a patient hospitalized because of a urinary tract infection (UTI) has a severe infection, and whether he or she is at high risk for harboring a multiresistant pathogen, are scant. The aims of the present study were to find (1) clinical and laboratory variables known within 24 hours of admission that, combined in a logistic model, will point to a high or low probability of bacteremia and (2) variables that can be used to define patients at high risk for the subsequent isolation of a multiresistant uropathogen. METHODS: In a set of patients consecutively admitted to a department of medicine because of UTI, we compared bacteremic vs nonbacteremic patients, and patients with a multiresistant uropathogen vs others, on logistic regression analysis. The logistic models derived were validated in a second set of patients with UTI. RESULTS: Among 247 patients with UTI (median age, 75 years), 80 of them with bacteremia, five factors were significantly and independently associated with bacteremia: serum creatinine level, leukocyte count, temperature, diabetes mellitus, and low serum albumin level. A logistic model incorporating those factors was used to divide the patients into three groups with increasing prevalence of bacteremia (6%, 39%, and 69%) and of death (3%, 6%, and 20%). Three factors were predictive of the subsequent isolation of a resistant uropathogen: use of antibiotics before admission, advanced age, and male gender. The combination of those factors was used to divide patients into two groups, with resistance to cefuroxime of 9% vs 28%, to gentamicin of 7% vs 20%, and to sulfamethoxazole-trimethoprim of 30% vs 50%. In a second set of 144 patients with UTI, the percentages of bacteremia in the three groups were 5%, 16%, and 55%, and those of death, 2%, 6%, and 17%. When divided by the second model, the resistance to cefuroxime in the two groups was 16% vs 30%; to gentamicin, 16% vs 28%; and to sulfamethoxazole-trimethoprim, 28% vs 59%. CONCLUSIONS: If prospectively validated in other settings, the models can be used to define groups of patients with UTI at low and high risk for bacteremia, and to help in the choice of empiric antibiotic treatment.

Adolescent↗
PubMed1992

Disease patterns of patients with systemic lupus erythematosus as shown by application of factor analysis.

Clinical and laboratory test data of 77 patients with systemic lupus erythematosus (SLE) were evaluated by factor analysis. Six factors representing disease patterns were extracted: cutaneous symptoms of alopecia, malar rash, rash and photosensitivity; renal involvement; the anticoagulant syndrome of phlebitis and partial thromboplastic time inversely related to platelet count; lymphopenia; viral or fibromyalgia symptoms of headache, nervousness, joint and muscle pain; and serology of anti-DNA antibodies and complement inversely related. Application of factor analysis reveals various clinical presentations of SLE.

Adult↗
PubMed1991

Primary fibromyalgia and the chronic fatigue syndrome.

Thirty-three primary fibromyalgia patients were investigated for chronic fatigue syndrome symptoms. Significant fatigue was reported by 21/33 patients (63.6%), and patients reported various flulike symptoms, yet only 7/33 patients (21.2%) fulfilled criteria for the chronic fatigue syndrome. Only one patient reported painful lymph glands and four patients reported fever. Thus, symptoms of painful glands or fever might serve as clinical indicators, distinguishing between fibromyalgia and the chronic fatigue syndrome.

Diagnosis, Differential↗
PubMed1991

Predictive index for optimizing empiric treatment of gram-negative bacteremia.

In a survey of 296 episodes of gram-negative bacteremia in 286 patients (aged 13-99 years), four clinical variables were found to predict both significantly and independently the subsequent isolation of a multiresistant strain; hospital acquisition of the infection, antibiotic treatment before the bacteremic episode, endotracheal intubation, and thermal trauma as the cause of hospitalization. These variables were combined in an index that served to classify the patients into four groups with an increasing prevalence of multiresistant strains, Pseudomonas isolates, and isolates resistant to each of the antibiotic drugs in common use. For example, the percentage of isolates susceptible to cefuroxime in the four groups were 79%, 56%, 34% and 25%, and to gentamicin, 89%, 79%, 46%, and 33% (P less than .001 for both comparisons). The performance of the index was validated in a second group of 144 episodes of gram-negative bacteremia. The index kept its discriminative power. Compared with the prescriptions of the attending physicians, the index could probably have improved empiric antibiotic treatment in 24% of patients.

Adolescent↗
PubMed1991

Risk factors for development of diabetic nephropathy and retinopathy in Jewish IDDM patients.

Risk factors associated with diabetic microvascular complications, with special reference to ethnic origin, were looked for in 231 young Jewish insulin-dependent diabetes mellitus (IDDM) patients with duration of diabetes greater than or equal to 10 yr. Median age at diagnosis of diabetes was 9.2 yr (range 0.04-26.2 yr), and median duration of the disease was 15.3 yr (range 10.0-37.2 yr). Sixty-three percent of the patients were Ashkenazi Jews, and 37% were non-Ashkenazi Jews. HbA1 was evaluated every 3 mo in the last 10 yr of follow-up, and albumin excretion rate was tested in three 24-h urine collections. Direct and indirect ophthalmoscopy was performed every year since diagnosis of diabetes, and if retinal pathology was suspected, color photographs were taken. Microalbuminuria was detected in 31% and macroalbuminuria in 7% of the patients. Nonproliferative and proliferative retinopathy was found in 44 and 12% of the patients, respectively. On logistic regression analysis, two variables were significantly and independently associated with diabetic nephropathy--non-Ashkenazi origin and mean HbA1 values over the first 5 of 10 yr of follow-up. Variables significantly and independently related to diabetic retinopathy were non-Ashkenazi origin, mean HbA1 values over the last 10 yr of follow-up, and duration of diabetes. Because non-Ashkenazi Jews in Israel are of lower socioeconomic status than Ashkenazi Jews, we stratified our patients according to their socioeconomic parameters, median HbA1 values, and duration of diabetes. Non-Ashkenazi patients were at a higher risk to develop complications in all strata.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗
PubMed1991

Bacteremia in adult diabetic patients.

OBJECTIVE: To compare the microbiology, sources, complications, and outcome of bacteremia in diabetic and nondiabetic patients. RESEARCH DESIGN AND METHODS: A prospective study was conducted of all episodes of bacteremia in hospitalized diabetic and nondiabetic patients. The study consisted of patients greater than or equal to 18 yr of age with bacteremia detected within a 19-mo interval. RESULTS: We compared 124 episodes of bacteremia in 119 diabetic patients to 508 episodes in 480 nondiabetic patients. Diabetic patients were older than nondiabetic patients (median age 74 vs. 68 yr, P = 0.0001). In patients with an indwelling urinary catheter and bacteremic urinary tract infection, the percentage of Klebsiella in diabetic patients was 60% (6 of 10) and in nondiabetic patients was 17% (4 of 23, P = 0.04). In patients without an obvious source of bacteremia, the percentage of staphylococcal isolates in diabetic patients was 29% (10 of 35) and in nondiabetic patients was 14% (24 of 176, P = 0.04). Staphylococci were a common cause of bacteremic infections of the extremities in diabetic patients (12 of 19, 63%) and nondiabetic patients (20 of 50, 40%). Septic shock was the only complication that was more common in diabetic patients. The mortality in diabetic and nondiabetic patients was 28 and 29%, respectively. CONCLUSIONS: Our results represent elderly patients with non-insulin-dependent diabetes mellitus. In this group, empirical treatment for suspected bacteremic urinary tract infection in patients with a urinary catheter should include coverage for Klebsiella. Empiric treatment for suspected bacteremia of unknown origin or caused by infection of the extremities should include an antistaphylococcal drug. The prognosis of bacteremia in diabetic and nondiabetic patients was similar.

Adult↗
PubMed1991

Single-dose antibiotic treatment for symptomatic urinary tract infections in women: a meta-analysis of randomized trials.

The efficacy of single-dose antibiotics for treatment of symptomatic urinary tract infections in women was compared to the efficacy of conventional therapy in 25 controlled studies. The combined results of these studies indicate that single-dose antibiotics are less effective than conventional therapy at 3-14 days post-treatment (odds ratio of 0.5, 95 per cent confidence interval (C.I.) 0.4-0.7), and at 4-6 weeks (odds ratio of 0.4, 95 per cent C.I. 0.3-0.6). Single-dose therapy did not perform better in patients with bacterial isolates sensitive to the drug used. The cure rate achieved by single-dose amoxicillin was significantly lower than that afforded by conventional therapy. The equal efficacy of single-dose and conventional trimethoprim/sulphamethoxazole treatment at 3-14 days post-treatment could not be ruled out with a 95 per cent certainty. However, conventional treatment achieved cure rates significantly higher than single-dose therapy at 4-6 weeks (odds ratio 0.48, 95 per cent C.I. 0.3-0.8). Side-effects were lower among patients given a single dose (odds ratio 0.5, 95 per cent C.I. 0.4-0.6). Although single-dose trimethoprim/sulphamethoxazole is less effective than a course of treatment, it causes fewer side-effects: the decision of whether to use a single-dose has to be decided by cost-benefit analysis in any specific health-care system.

Amoxicillin↗
PubMed1991

Bacteremia in febrile patients. A clinical model for diagnosis.

Among 244 patients aged 18 to 98 years who were consecutively hospitalized in a department of internal medicine because of a febrile disease, 52 (21%) were bacteremic. On a logistic regression analysis, five variables known within 24 hours of admission were found to be associated both significantly and independently with bacteremia: low serum albumin level, low premorbid performance status, chills, renal failure, and an assumptive diagnosis of urinary tract infection on admission. The logistic model was used to divide patients into three groups. In group 1, the percentage of bacteremic patients was 5%, in group 2, 40%, and in group 3, 83%. The percentage of deaths in the three groups was 0%, 23%, and 50%, respectively. The model was validated in a second group of 257 patients. The percentage of bacteremia was 1% in group 1, 23% in group 2, and 65% in group 3. The death rate in three groups was 3%, 4%, and 35%, respectively. The accuracy of the attending physician in diagnosing bacteremia within 24 hours of hospitalization was compared with that of the model. Use of the model could have improved the diagnostic accuracy in 5% of the patients in group 1 and in 18% of patients in group 3.

Aged↗
PubMed1991

Alopecia in systemic lupus erythematosus. Relation to disease manifestations.

Alopecia was observed in 40/74 (54%) patients with systemic lupus erythematosus (SLE). Patients with alopecia had a significantly higher rating for cutaneous manifestations, Raynaud's phenomenon and muscle tenderness, and most of these signs correlated with the magnitude of alopecia. There was no difference between patients with or without alopecia for arthritis, nephritis or central nervous system manifestations. Alopecia correlated with disease activity index but did not correlate with various specific measurements of disease exacerbation.

Adult↗
PubMed1990

Accelerated heme synthesis and degradation in transformed fibroblasts.

Various parameters of the heme biosynthetic pathway were studied in two cell lines, one nontransformed and the other malignantly transformed (MLV/MS), both replicating at the same rate. Using the above system enabled us to distinguish between phenomena characteristic of the malignant transformation per se and those due to accelerated growth rate. Heme synthesis and degradation as well as the activities of ALAS, ALAD, PBGD, and FC were found to be increased in the transformed cells. However, the concentration of intracellular heme was markedly reduced from 30.4 +/- 4.4 pmole/mg protein in nontransformed cells to 10.5 +/- 2.6 pmole/mg protein in transformed cells. These observations show that malignant transformation leads to changes in heme metabolism unrelated to growth rate in this cell line.

Animals↗
PubMed1990

Effects of fish-oil ingestion on cardiovascular risk factors in hyperlipidemic subjects in Israel: a randomized, double-blind crossover study.

Effects of a daily fish-oil supplement on serum lipids, apolipoproteins, and some platelet functions and hemorheologic variables were examined in 27 hyperlipidemic subjects in a randomized, controlled, double-blind, crossover fashion with an identically encapsulated vegetable oil serving as the control treatment. Despite the habitual high linoleic acid intake of the study population, significant incorporation of n-3 (omega-3) fatty acids into the serum, platelet, and erythrocyte lipids was observed after the fish-oil supplement. Ingestion of fish oil resulted in a 40% decrease in the triglyceride concentration, a 12% increase in HDL cholesterol, and a significant decrease in plasma viscosity, whereas the vegetable-oil placebo had no significant effect. We conclude that a moderate intake of fish oil (15 g/d) is a feasible treatment for hypertriglyceridemia even in patients with a background of high linoleic acid intake and that it may have a beneficial effect on several cardiovascular risk factors.

Apolipoproteins↗