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A Buré

Publications and source records attributed to A Buré.

At least 19 recordsLinked to original sources

Results of culture form colonoscopically obtained specimens for bacteria and fungi in HIV-infected patients with diarrhea.

BACKGROUND: The aim of our study was to determine the diagnostic yield of culture for bacteria and fungi from colonic biopsy specimens in 290 consecutive HIV-infected patients with diarrhea. METHODS: During each colonoscopy, three biopsy specimens were homogenized and cultured on media for Salmonella and Shigella and for Campylobacter and Yersinia, on Loewenstein medium and on Sabouraud medium. RESULTS: Cultures were found positive for one (n = 32) or two (n = 5) infectious agents in 37 cases, i.e., in 12.8% of the patients. Bacteria were isolated in 24 cases, and identified as Campylobacter jejunl-coli (n = 14), Salmonella (n = 2), Shigella (n = 1), or Pseudomonas aeruginosa (n = 7). Among the 14 patients with C. jejuni-coli intestinal infection, 11 had normal-appearing mucosa at colonoscopy, and 3 had a concomitant stool culture negative for Campylobacter. Mycobacterial cultures were positive for Mycobacterium avium intracellulare in 6 patients, who were already known as having a disseminated M. avium intracellulare infection from positive blood cultures. Fungal cultures were positive for Candida in 10 cases, without clear clinical significance. CONCLUSIONS: The overall yield of culture for bacterial pathogens from colonic tissue in HIV-infected patients with diarrhea is low, but some individual cases of C. jejuni-coli infections may be detected from colonic tissue culture and not diagnosed by concomitant stool culture.

AIDS-Related Opportunistic Infections

[HIV infection and "malignant" strongyloidiasis].

Disseminated Strongyloides stercoralis infection occurs in immunocompromised patients. Despite the epidemiological overlap of HIV infection and strongyloidiasis observed in certain parts of the world, only six cases of dissemination have been reported in AIDS patients. The clinical presentation has no special features, except for the frequency of other opportunistic infections. The prognosis is poor. This lack of association between disseminated strongyloidiasis and HIV infection had led to the exclusion of extra-intestinal forms of this paraistosis from the revised classification of AIDS.

HIV Infections

Vancomycin-aminoglycoside combinations in therapy of endocarditis caused by Enterococcus species and Streptococcus bovis.

Between 1974 and 1986, five patients with enterococcal endocarditis (three of whom had a prosthetic valve) and three patients with Streptococcus bovis endocarditis were treated with a combination of vancomycin and an aminoglycoside for a mean duration of 40 days. This regimen was prescribed because of allergy to beta-lactam (n = 7) and/or failure of previous treatment (n = 4). Three of the eight patients underwent valve replacement. In the six evaluable patients cure was achieved with the vancomycin-aminoglycoside combination. An increase of the creatinine serum levels was observed in all cases but it was never necessary to discontinue treatment, adjustment of the vancomycin and aminoglycoside dosage according to the serum and/or serum creatinine levels allowing continuation of therapy.

Adult

Activity of sulbactam in combination with ceftriaxone in vitro and in experimental endocarditis caused by Escherichia coli producing SHV-2-like beta-lactamase.

We studied the efficacy of sulbactam, a beta-lactamase inhibitor, in combination with ceftriaxone in vitro and in experimental endocarditis due to an Escherichia coli strain producing an extended-spectrum beta-lactamase most similar to SHV-2, a new mechanism of resistance to broad-spectrum cephalosporins among members of the family Enterobacteriaceae. In vitro, ceftriaxone demonstrated an important inoculum effect (MICs were 2 and 256 micrograms/ml with 5 X 10(5) and 5 X 10(7) CFU of inoculum per ml, respectively). Sulbactam inhibited the beta-lactamase degradation of ceftriaxone and enhanced the killing by ceftriaxone with both inocula tested. In vivo, sulbactam (100 mg/kg every 8 h) or ceftriaxone (15 or 30 mg/kg every 24 h) alone were ineffective after a 4-day therapy. The addition of sulbactam to ceftriaxone (15 mg/kg) or to the ceftriaxone (15 mg/kg)-netilmicin (6 mg/kg every 24 h) combination produced a reduction of 2 log10 CFU/g of vegetation greater than that produced by therapy without sulbactam. The sulbactam-ceftriaxone (30 mg/kg) combination produced a reduction of almost 5 log10 CFU/g of vegetation greater than that produced by single-drug therapy (P less than 0.01), sterilized five of eight vegetations (versus none of seven for ceftriaxone [30 mg/kg] alone; P less than 0.05), and was as effective as the ceftriaxone (15 mg/kg)-sulbactam-netilmicin combination. We concluded that (i) SHV-2 production was responsible for ceftriaxone failure in vivo, probably because of the high inoculum present in vegetations; (ii) sulbactam used in a regimen which provided levels in serum constantly above 4 micrograms/ml and a vegetation/serum peak ratio of approximately 1:3 enhanced the activity of a broad-spectrum cephalosporin in a severe experimental infection; and (iii) the highest dose of ceftriaxone in combination with sulbactam was as effective as the lowest dose of ceftriaxone plus sulbactam plus an aminoglycoside.

Animals

Detection of extended broad-spectrum beta-lactamases in Enterobacteriaceae in four French hospitals.

In 210 strains of Enterobacteriaceae which were isolated in four hospitals and which showed reduced susceptibility to cefotaxime, high synergy was demonstrated between amoxicillin (20 micrograms) + clavulanate (10 micrograms) and cefotaxime (30 micrograms) using a simple double-disk test. Isoelectric focusing on gel and specific iodometric detection using ceftriaxone identified four extended broad-spectrum beta-lactamases (isoelectric points 7.6, 6.3, 7.0 and 5.9) produced by the strains.

Amoxicillin

[Retrospective bacteriological study of mycobacterial infections in patients with acquired immunodeficiency syndrome].

The main species of mycobacteria isolated in 62 of the 316 acquired immunodeficiency syndrome patients admitted to the Claude Bernard Hospital, Paris, between January, 1983 and October, 1986 were studied retrospectively according to their site of isolation and their pathogenic role. Mycobacterium tuberculosis was isolated in 19 cases (from pulmonary specimens in 17 cases); this species was present in 59 percent of our African patients as against 20 percent of our European patients. M. avium intracellulare was isolated in 33 cases (17 from blood, 12 from the lung and 11 from the gastrointestinal tract) and was found in 55 p. 100 of our European patients. Other species that were isolated less frequently were M. xenopi (5 cases), M. kansasii (3 cases), M. aurum, M. chelonae, M. fortuitum, M. gordonae, M. simiae and M. terrae (1 case each). Post mortem specimens obtained from 110 acquired immunodeficiency syndrome patients were cultivated during the same period. In 20 patients, at least one specimen was positive for a mycobacterium: M. tuberculosis in 2 cases, M. avium intracellulare in 18 cases. Twenty-nine of the 33 patients in whom M. avium intracellulare was isolated were considered a posteriori as being infected by this organism. The therapeutic approach varies according to the species involved. No treatment seems to be truly effective against M. avium intracellulare. Pending the results of cultures, no direct bacteriological examination can provide information on the mycobacterial species concerned; however, a conventional antituberculosis treatment may be instituted, particularly in patients from Africa or Haiti.

Acquired Immunodeficiency Syndrome

Dissemination in five French hospitals of Klebsiella pneumoniae serotype K25 harbouring a new transferable enzymatic resistance to third generation cephalosporins and aztreonam.

A strain of Klebsiella pneumoniae K25 resistant to newer beta-lactam drugs was isolated in clusters in five hospitals in the Paris area. The MICs of ceftazidime and aztreonam (greater than or equal to 128 mg/l) were higher than that of cefotaxime (16 mg/l) for the strain but, when measured in the presence of clavulanic acid, they were less than or equal to 1 mg/l. The donor strains and derivatives produced a beta-lactamase with a pI of 7.75-7.8 and hydrolysing activity against a wide spectrum of beta-lactams similar to that of SHV-2 and SHV-3, but with significant hydrolysis of ceftazidime. This new enzyme could be designated SHV-4.

Aztreonam

Comparative efficacy of cefotiam, cefmenoxime, and ceftriaxone in experimental endocarditis and correlation with pharmacokinetics and in vitro efficacy.

To determine the influence of in vitro activity, pharmacokinetic properties, and therapeutic regimen on the antibacterial effect in vivo, we compared three cephalosporins, cefotiam, cefmenoxime, and ceftriaxone, in a rabbit model of experimental Escherichia coli endocarditis after 4 days of treatment. The MBCs of cefotiam, cefmenoxime, and ceftriaxone for the E. coli strain were 0.5, 0.125, and 0.06 microgram/ml, respectively. Killing curves at 10 times the MBC were similar for the three cephalosporins. In serum, the elimination half-life of ceftriaxone was twice as much as the elimination half-life of cefotiam or cefmenoxime (2.8 +/- 0.45 versus 1.4 +/- 0.25 or 1.3 +/- 0.4 h, respectively). Ceftriaxone was much more effective than cefotiam. The bacterial titer in the vegetations (log10 CFU per gram of vegetation) was 7.56 +/- 1 with cefotiam and 2.41 +/- 2.6 with ceftriaxone, as their concentrations were 18 and 466 times higher, respectively, than their MBCs. Although ceftriaxone and cefmenoxime exhibited a similar rate of killing and percentage of protein binding, ceftriaxone was more effective than cefmenoxime at the same regimen of 15 mg/kg twice a day (3.08 +/- 1.1 versus 4.82 +/- 3.2 log10 CFU/g of vegetation). When antibiotic was given as a single daily injection of 30 mg/kg, the antibacterial effect persisted for ceftriaxone, but not for cefmenoxime. The longer elimination half-life and the higher local concentration/MBC ratio of ceftriaxone explained these results. The bacterial titer measured 24 h after the fourth injection of 30 mg of ceftriaxone per kg confirmed that this regimen prevented regrowth of bacteria. These results suggest that the local antibiotic level/MBC ratio roughly correlated with the antibacterial effect and could represent an adequate basis to explain the differences observed between the drugs in vivo. They also demonstrate that, provided that the dose is sufficient, a long-acting broad-spectrum cephalosporin may be effective in severe gram-negative infections, even when given at relatively long dosing intervals, in contrast with a rapidly cleared drug with the same intrinsic activity.

Animals

Mycobacterium simiae and Mycobacterium avium-M. intracellulare mixed infection in acquired immune deficiency syndrome.

Acquired immune deficiency syndrome was diagnosed in a 43-year-old man, born and living in Congo. The patient presented a disseminated infection caused by mycobacteria which were recovered from blood, jejunal fluid, and duodenal and rectal biopsies. Identification, according to conventional tests and mycolate profile determination, showed that Mycobacterium avium-M. intracellulare and M. simiae were both involved.

Acquired Immunodeficiency Syndrome

[Failure of new beta-lactam antibiotics in the treatment of severe Enterobacter cloacae infections].

In 12 patients infected with an Enterobacter cloacae (E. cl.) initially susceptible to the 3rd generation cephalosporins, we observed the emergence in vivo of variants resistant to most of the new beta-lactam antibiotics (carboxy-penicillins, ureido-penicillins, 3rd generation cephalosporins and aztreonam). These variants remained susceptible to mecillinam and imipenem. The variant emerged under treatment with cefotaxime in 3 cases, with moxalactam in 3 cases, with aztreonam, carbenicillin, and ticarcillin in 1 case each and without treatment in 1 case. An aminoglycoside was combined with the beta-lactam antibiotic in 6 cases. Therapeutic failure was attributed to emergence of the resistant variant in 6 out of 12 cases (with an aminoglycoside in 3 cases, with the beta-lactam antibiotic alone in 3 cases). These case reports underline the importance of bacteriological monitoring of patients infected with E. cl. treated with a beta-lactam antibiotic. The susceptibility to beta-lactam antibiotics of the E. cl. strains isolated during treatment should be systematically retested.

Adult

Epidemiological features of Legionnaires' disease in the Paris area.

Although the first French case of Legionnaires' disease (LD) was diagnosed in 1979 and the first six serogroups of L. pneumophila and L. longbeachae serogroup 2 were demonstrated in environmental samples from the Paris area, the incidence of the disease has not yet been evaluated in France. Prevalence of antibodies, as detected by an immunofluorescent assay, in the Paris population of our study ranged from 0.9 to 2.2%. LD was demonstrated in 155 (4.4%) of 3502 patients investigated mainly by serology. In a prospective study in a respiratory intensive care unit 20 (7.8%) cases of pneumonia out of 257 were caused by L. pneumophila. 171 of the 175 cases of LD diagnosed in Paris during 33 months were caused by L. pneumophila serogroup 1. Risk factors and epidemiological features of patients are similar to those described in other countries.

Adult