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F Dalet

Publications and source records attributed to F Dalet.

At least 19 recordsLinked to original sources
PubMed2001

Sequence microdiversity at the ribosomal RNA operons of Escherichia coli pyelonephritogenic strains.

OBJECTIVE: To determine whether Escherichia coli strains isolated from patients with uncomplicated acute pyelonephritis can be distinguished from those isolated from patients with complicated acute pyelonephritis on the basis of the genetic background. METHODS: In total, 103 E. coli strains isolated from patients with acute pyelonephritis (59 uncomplicated pyelonephritis (UAP) and 44 complicated pyelonephritis (CAP)) were characterized by RFLP of the intergenic spacer region 16S-23S rRNA, the presence of three alternative sequences found in the polymorphic V6 loop of the 16S rRNA gene, the presence of the pap gene, and antibiotic susceptibility. RESULTS: At similarity levels of 70%, four RFLP groups (alpha1, alpha2, beta1 and beta2) were discerned. Strains from UAP were statistically significant for alpha RFLP, with a strong association with the presence of the pap gene, V6-I sequence and antibiotic multisensitivity. Strains from CAP randomly belonged to the alpha or beta RFLP groups, with a very low presence of the pap gene, and random presence of V6 sequences, and were multiresistant to antibiotics. When the CAP strains were distributed according to underlying pathology, non-obstructive cases had RFLP and V6 polymorphisms similar to those of UAP cases, while obstructive cases were clearly distinct. CONCLUSIONS: UAP and non-obstructive CAP E. coli strains are sensitive to antimicrobials, show a high level of the pap gene and belong to the selective, homogeneous and highly protected molecular alpha2 group, where no recombinations, deletions or insertions are present. On the contrary, obstructive and vesicorenal reflux E. coli strains show significant antimicrobial resistance, high intercistronic heterogenicity (wide presence of block nucleotidic substitutions, deletions or insertions) and significantly lower virulence.

Acute Disease↗
PubMed1997

New fimbrial adhesins of Serratia marcescens isolated from urinary tract infections: description and properties.

Fimbriation, hemagglutination and adherence properties were studied in two strains of S. marcescens (ATCC 43820 and 43821) isolated from the urine of two hospitalized patients in two different hospitals. Studies were performed using electron microscopy (EM), fimbrial purification, recombinant DNA and hemagglutination techniques, hydrophobicity and tests of adherence to uroepithelial cells, catheters and glass. In EM, fimbriae of these two strains showed an inner channel and were 11 nm. thick and 0.76-1.08 microns long. Original strains and the clone GH42-pSF192 (recombinant DNA prepared using E. coli GH42 as recipient and the cosmid SuperCos 1 as a vector) versus negative control (E. coli GH42-SuperCos 1) showed mannose-resistant hemagglutination of tanned erythrocytes and yeast, high hydrophobicity (55.4 and 49.6% at 37C versus 22.8%) and high adherence to borosilicate glass (313,000 and 168,000 CFU/cm.2 versus 17,000 CFU/cm.2), catheters (4.7 x 10(6) and 1.0 x 10(6) CFU/cm.2 versus 3.9 x 10(4) CFU/cm.2) and uroepithelial cells (adherence indexes of 3.82 and 3.29 versus 1.25). The properties of the fimbriae studied were different from those previously described in the genus Serratia, and they were designated as MR/T.

Adhesins, Bacterial↗
PubMed1996

Single-dose rufloxacin versus 3-day norfloxacin treatment of uncomplicated cystitis: clinical evaluation and pharmacodynamic considerations.

The efficacy and safety of rufloxacin (400 mg, single dose) were compared to those of norfloxacin (400 mg twice a day for 3 days) for the treatment of women with uncomplicated cystitis. In addition, urine levels, drug level/MIC ratio, and urine antibacterial activity 72 to 84 h after treatment initiation were determined in a subgroup of patients for pharmacodynamic assessment. A total of 203 women were included and treated in this open, randomized clinical trial; 100 patients received norfloxacin, whereas 103 received rufloxacin. Of these, 156 (74 and 82 patients in the norfloxacin and rufloxacin groups, respectively) were considered bacteriologically evaluable. At the first follow-up visits (3 to 12 days after starting the treatment), bacteriological cure rates were 99 and 94% for norfloxacin and rufloxacin, respectively. Seventy-nine percent (119 of 150) of bacteriologically cured patients attended a long-term follow-up visit (4 to 6 weeks after starting the treatment), where a relapse rate of 4% (2 of 54) and 5% (3 of 64) were found in the norfloxacin and rufloxacin groups, respectively. The pharmacodynamic evaluation performed in 35 patients showed similar median urine levels (approximately equal to 25 micrograms/ml) and urine antibacterial activity for both treatment groups against initial isolates, despite a higher norfloxacin level/MIC ratio due to the lower MIC of norfloxacin. Twenty-one patients (20%) in the rufloxacin group and 12 patients (12%) in the norfloxacin group reported 39 and 16 adverse events, respectively, almost all of them being mild and lasting < 24 h. Overall, gastrointestinal reactions were the most frequent adverse events reported. However, 12 patients treated with rufloxacin reported 15 central nervous system adverse events. This study shows that single doses of rufloxacin are as effective as a norfloxacin 3-day standard treatment in uncomplicated cystitis. The results obtained with rufloxacin are consistent with its pharmacodynamic properties.

Adult↗
PubMed1995

Evaluation of a new agar in Uricult-Trio for rapid detection of Escherichia coli in urine.

A new commercial agar (Uricult-Trio) with 8-hydroxyquinoline-beta-glucuronide was used to assess 2,536 uropathogens for beta-glucuronidase activity typical of Escherichia coli. Included in the study were 1,807 strains of the family Enterobacteriaceae, 284 strains of nonfermentative bacilli, 345 strains of gram-positive cocci, and 100 yeast strains. In identifying E. coli, the test agar gave a sensitivity of 95.5% and a specificity of 97.2%. Fifty E. coli isolates gave negative reactions; 31 non-E. coli strains produced black colonies characteristic of E. coli. No growth of gram-positive cocci and no false-positive reactions from yeasts were observed. The recovery rate for E. coli on this agar was at least 10% higher than that on blood agar.

Agar↗
PubMed1993

Antimicrobial prophylaxis in urologic surgery: does it give some benefit?

Three types of antibiotic prophylactic regimens were evaluated versus a control without prophylaxis (group A: 3,912 cases) in urologic surgery. The antibiotic regimens were: group B = cefazolin 1 g/12 h/3 days (3,660 cases); group C = cefonicid 1 g/24 h/3 days (2,076 cases), and group D = cefonicid 1 g single dose (3,169 cases). The parameters used were the comparison of the corresponding rates of postsurgical sepsis and operative wound infections. Numeric investigations for the validity of a retrospective study (unpaired data) were performed: homogenicity test, relative risk point estimate and confidence limits (95%), and etiological fraction point estimate and confidence limits (95%). Chi-square for other purposes were performed. Endoscopic handling was considered homogeneous (same infective risk), while open surgery was heterogeneous (p < 0.001). In order to avoid probable bias, a correction factor was used. Although in different degrees, prophylaxis significantly reduced the morbidity of surgical wound infections (p < 0.001; etiological fraction > 90%). The differences (p < 0.01) between groups B and C/D were attributed to pharmacokinetic causes (short T 1/2 of cefazolin). To obtain the maximum protective effect, the use of antibiotics with a T 1/2 of > 4 h is suggested. There was no resistant mutans in previously sensitive strains. However, a significant selection of intrinsically resistant strains was observed. Monodose offers at lest the same advantages as multiple-dose therapy. In addition, the monodose selected in a lesser proportion both the resistant strains (p < 0.001) and the number of microbial associations (p < 0.01).

Cefazolin↗
PubMed1992

[Prevalence and treatment of bacteriuria in the geriatric population].

The aim of this study was to evaluate the prevalence of asymptomatic bacteriuria and its prognostic factors in a geriatric population living in a nursing home. Seventy-eight patients (68 females, 10 males) with a mean age of 82 +/- 6 years (range: 60-94) were studied. Once symptomatic infection is ruled out and the risk factors had been analyzed, a urine culture was performed in all cases. We then identified two different population groups: asymptomatic bacteriuria without risk factors (group A), and asymptomatic bacteriuria with risk factors (group B). Overall prevalence of asymptomatic bacteriuria was 38.5% (Group A: 23%, group B: 63%; p < 0.001). Considering all patients with bacteriuria, 50% of cases (15 out of 30 patients) had urine incontinence, 40% suffer from severe limitation of movements and 70% had a past history of pregnancy. The same figures for the population with negative urine culture were 12.5%, 14.5%, and 46% respectively (p < 0.01). In group B, 79% of cases had more than one RF, including all patients with the association of urine incontinence, movement limitation and diabetes. In group A, 93% of asymptomatic bacteriuria were due to E. coli with low adhesin expression (27%) whereas in group B, E. coli was isolated in 44% asymptomatic bacteriuria cases, with high adhesin expression (71.5%), other enteric gram-negative bacilli (31%), non-fermentative gram-negative bacilli (19%) and gram-positive cocci (6%). Group A patients were treated with a single dose of ciprofloxacin (500 mg) with elimination of bacteria in urine in 91% of cases (at one week) and 73% of cases (at one month).(ABSTRACT TRUNCATED AT 250 WORDS)

Adult↗
PubMed1991

Frequency and distribution of uropathogenic Escherichia coli adhesins: a clinical correlation over 2,000 cases.

In order to determine the pathogenic responsibility of Escherichia coli adhesins (ADHs) in urinary infections (UI), 2,000 different patients suffering different clinical urinary and male sexual gland infections were monitored. The ADHs were determined by agglutination techniques with human and guinea-pig red blood cells, Candida albicans and Saccharomyces cerevisiae cells and latex sensitized with GAL-GAL. In uncomplicated UIs, the possession of ADH is the main invasion mechanism for E. coli. The rate of E. coli ADH strains is very high (89%) in acute cases (727 of 818 cases: 310 of 362 cystitis; 104 of 113 recidivant cystitis; 120 of 126 pyelonephritis; 158 of 173 prostatitis, and 34 of 43 orchiepididymitis) and rare (10%) in asymptomatic or chronic cases (24 of 235 cases: 14 of 148 bacteriurias; 8 of 74 prostatitis, and 2 of 13 orchiepididymitis). A close relation is established between the presence of ADH and clinical symptoms. 90% (218 of 242) of acute cases with systemic symptoms are due to MR-type ADH strains, especially the P subtype. 71% (409 of 576) of acute cases with local symptoms are due to MS-type ADH strains. In complicated UIs the expression of ADH is not an essential condition for the invasion of the urinary apparatus. It has been strongly suggested that males are significantly more resistant to UI, both in the tract and parenchyma, than women. It can be deduced that the underlying disease is more liable to UI the lower the adherence level shown by isolated strains. Thus catheters, reflux and neurogenic bladder are, by far, more aggressive alterations than the prostatic adenoma, vesical tumor or lithiasis.

Adhesins, Escherichia coli↗
PubMed1989

Ticarcillin/clavulanate in severe infections in patients with varying renal function.

The therapeutic efficacy of ticarcillin/clavulanate was assessed in 71 patients with severe infections: 38 acute pyelonephritis, 16 septicaemia and 19 miscellaneous infections. The patients were classified according to their renal function in: Group A, normal (16 cases); B, mild renal impairment (RI) with creatinine clearance (Clcr) between 80 and 40 ml/min (18 cases); C, moderate RI with Clcr between 40 and 15 ml/min (12 cases); D, severe RI with (Clcr) between 15 and 5 ml/min (13 cases) and E, terminal with (Clcr) less than 5 ml/min (12 cases). A total of 105 microorganisms (48.6% resistant to ticarcillin): 31 Pseudomonas aeruginosa, 18 Escherichia coli, 21 other Enterobacteriaceae, 2 Haemophilus influenzae, 10 Bacteroides spp., 14 enterococci, 8 staphylococci and 1 streptococcus, were isolated. All except six Ps. aeruginosa were sensitive to ticarcillin/clavulanate, using 75:10 microgram discs. Bacteriological eradication was obtained in 97% of the cases on the third day and at the end of treatment, and in 82% of the cases after one month. In all the assessable cases, the clinical symptoms disappeared on the third day except in one patient who developed a resistant strain (Klebsiella oxytoca). The wide range of bacteria assessed and the clinical-bacteriological success rates demonstrated that the ticarcillin/clavulanate combination had an efficacy/safety profile that could be considered excellent. Tolerance was good and side effects were not observed. This study confirms the practical efficacy of the recommended dosages derived from our previous kinetic studies in RI.

Adult↗
PubMed1986

Pharmacokinetics of the combination of ticarcillin with clavulanic acid in renal insufficiency.

The pharmacokinetics of ticarcillin and clavulanic acid were studied by blood and urine assay methods in 25 patients divided into five groups with varying degrees of renal insufficiency i.e. mild, moderate and severe renal insufficiency, almost anuric patients and those requiring haemodialysis (groups A to E). A single dose of 5.2 g Timentin (5.0 g ticarcillin and 200 mg clavulanic acid) was administered intravenously by infusion over 30 min. The average elimination half-life (T1/2) of ticarcillin increased from 0.95 h in patients with creatinine clearance (Clcr) of 80 ml/min to 1.8, 4.4, 6.9 and 11.2 h respectively in mild, moderate and severe renal insufficiency and in almost anuric patients. The T1/2 values for clavulanic acid were 0.75, 0.9, 2.0, 2.5 and 4.8 h in the same groups. The area under concentration-time curve (AUC) for ticarcillin increased from 787 to 2839 mg/l/h and for clavulanic acid from 12.8 to 29 mg/l/h when group mean values from patients with mild and severe renal insufficiency were compared. The plasma clearance (Clpl) of clavulanic acid was in all groups greater than that of ticarcillin i.e. 166 and 100 ml/min vs. 79.2 and 25.0 ml/min when comparing mean values from groups with mild and severe renal insufficiency respectively. The plasma clearance ratio clavulanic acid/ticarcillin increased proportionally to the degree of renal insufficiency from a value of 1.5 in normal subjects to between 3.3 and 3.8 in more advanced cases.(ABSTRACT TRUNCATED AT 250 WORDS)

Acute Kidney Injury↗
PubMed1982

An assessment of the intramuscular and intravenous administration of mezlocillin in urinary tract infections.

The efficacy of mezlocillin in urinary tract infections was assessed using both the intramuscular and intravenous route. Patients with comparable diseases were divided into two groups. The microorganisms were sensitive to mezlocillin. Thirty patients were given i. m. doses and 20 i. v. doses. These patients had upper or lower urinary tract infections. The doses were 2 g i. v. or 1 g i. m. every eight hours. Treatment lasted for an average of six days. The MICs for mezlocillin were determined for the strains isolated, all of which were gram-negative organisms, with the exception of nine enterococci. In addition, sensitivity to cephalothin, carbenicillin and gentamicin was determined using the disc diffusion test. The geometric means of the MICs for mezlocillin were 3.85, 2.8 and 1.3 mg/l against Escherichia coli, Proteus mirabilis and enterococci, respectively. There were no marked differences in activity between the i. m. and i. v. routes on Days 1, 7, 14, 30 and 60 after treatment. There was a short-term cure rate of 79% with mezlocillin, independent of the route of administration; reinfections were observed in 8% of the cases and the infection persisted in 13%. There are no significant differences between our results and those from other studies on mezlocillin and piperacillin. There was no indication of toxicity, nor were there deviations in the haematological and biochemical parameters. One patient had severe pruritus following each i. m. injection; the treatment had to be discontinued.

Humans↗
PubMed1981

Comparative pharmacoclinical evaluation between talampicillin and ampicillin in urinary infections.

500 mg of powdered ampicillin (AMP; activity 108%) and 325 mg of talampicillin chlorhydrate (TMP; equivalent to 200 mg ampicillin with an activity of 100%) were administered orally to two groups of 15 fasting patients selected at random. Blood samples were collected after 1/2, 1, 2, 4 and 6 h and urine samples after 1, 2, 4 and 6 h. The AMP concentrations were determined by the microbiologic method. All patients received food 1 h after the drugs administration. Urine samples wee taken daily for the bacteriologic examination. The maximum seric peak for TMP was 4.2 microgram/ml at 1/2 h and for AMP of 4.6 microgram/ml after 1 h. It was stated that TMP is absorbed more quickly than AMP and it was not affected by the presence of food. Nevertheless, no differences were observed in the results of the clinical study.

Ampicillin↗