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We determined the resistance to quinolone of 309 Salmonella enterica subsp. enterica serotype Typhimurium strains isolated from humans and animals (cattle, pigs, or poultry) in 1995 or 1996. Nalidixic acid resistance increased from 8.5% in 1995 to 18.6% in 1996. The highest resistance levels correlated with a mutation at Ser-83 (or Asp-82). All strains remained ciprofloxacin susceptible. Human and animal isolates were compared by pulsed-field gel electrophoresis, and the banding patterns of the human isolates most closely matched those of the bovine isolates.

To determine the prevalence of quinolone resistance in Salmonella typhimurium strains from humans or animals (cattle, poultry, swine), the S. typhimurium strains isolated at a teaching hospital and at the central veterinary laboratory of the same district between January 1, 1995, and December 31, 1996 were studied. Susceptibility to nalidixic acid was determined using the disk diffusion method. Strains with decreased susceptibility to nalidixic acid were subjected to minimal inhibitory concentration (MIC) determination for pefloxacin, ofloxacin, ciprofloxacin, norfloxacin, levofloxacin, and grepafloxacin. Decreased susceptibility to nalidixic acid was demonstrated for 41 of the 309 strains studied and increased from 8.5% in 1995 to 18.6% in 1996. MIC90 values of fluoroquinolones for strains with decreased susceptibility to nalidixic acid were lower than 1 mg/L, which is the cutoff above which a strain is classified as susceptible, but were higher than for strains that were susceptible to nalidixic acid. These low levels of resistance may be the first step in selection of mutant strains with high levels of resistance to fluoroquinolones. This warrants continued monitoring of resistance of Salmonella to fluoroquinolones.

Objective: To investigate the efficacy of a selective intrapartum prophylaxy of group B streptococci (GBS) infection of the neonates., Study Design: A prospective protocol of universal antepartum screening of GBS and selective intrapartum treatment from the 1st February 1994 to the 31st December 1995, on 2454 subsequent deliveries was designed. Our policy included: (1) antepartum screening as soon as possible after 28 weeks by a single vaginal and perianal sample for culture; (2) intrapartum recognition of one condition of high risk of fetal contamination during labor (these conditions included: a temperature of 38 degrees C during labor, rupture of membranes for more than 12 h or prolonged labor for more than 12 h with rupture of membranes, prematurity, twins, maternal diabetes, previous pregnancy with GBS infection of the neonate); and (3) intrapartum anti-bioprophylaxy (amoxicillin) for women with positive screening during pregnancy and one condition of high risk of fetal contamination during labor. We studied the outcome of neonates during this period to look for immediate GBS severe infection of the neonates in the form of bacteraemia or meningitis and compared the results with the rate of neonatal infection before this protocol (4.5/1000 live births in 1993)., Results: We noted that 11% of pregnant women were carriers, 25% of which led to antibiotic chemoprophylaxis during the labor. We noticed four cases of neonatal bacteraemia of GBS. One case arose from the group of carriers (but no condition of risk of fetal contamination during the labor and no chemoprophylaxy). The three other cases were from women with a negative antepartum screening. There was no case of meningitis and all four babies were in good health at day 10 of life. Comparing with results prior to the study, we noticed that the rate of neonatal bacteraemia dropped from 4.5 to 1.6 per 1000 livebirths (P < 0.0001)., Conclusion: This protocol of intrapartum anti-bioprophylaxy significantly decreases the rate of GBS neonatal sepsis. We propose to improve the efficacy of this prevention program, especially with regard to the method of antepartum screening of pregnant women colonized with GBS.

Over a 2-year period, we performed 33 bacteriological controls of drinking water supplied by refrigerated fountains located in a nursing home. Amongst 24 strains of gram-negative bacilli isolated from 16 samples. 10 were identified as belonging to the species Escherichia vulneris. Viable bacterial counts were always less than 10 ufc/100 ml. During the same period no clinical isolate of E. vulneris was recovered from the nursing home. The signification of E. vulneris in drinking water is unknown. However, considering that E. vulneris has been implicated as cause of various infections, its presence in potable water supply systems would seem to be a potential risk factor for severely immunocompromised patients.

We report the case of a nonimmunocompromised female patient, who developed exogenous lipoid pneumonia with Mycobacterium fortuitum infection at diagnosis, later followed by Aspergillus fumigatus infection. The association of exogenous lipoid pneumonia with atypical mycobacterial infection is uncommon but well-recognized, but, to our knowledge, association with A. fumigatus infection has not previously been reported.

Vancomycin-resistant enterococci have been isolated with increasing frequency since 1988. Thus far, most of these resistant enterococci have belonged to the Enterococcus faecium species, and epidemiological studies have shown a wide diversity among interhospital and intrahospital isolates. This report presents an epidemiologic investigation of 25 vancomycin-resistant Enterococcus strains--24 Enterococcus faecium and one Enterococcus gallinarum--isolated from the stools or blood of adult patients receiving intravenous vancomycin prophylaxis during neutropenia and hospitalized in a single hematologic unit. Macrorestriction patterns of total DNA and of ribosomal DNA regions were used to analyze the strains. Strains produced different total DNA restriction fragment length polymorphism patterns after SmaI digestion. Ribotyping was less discriminative than pulsed-field gel electrophoresis. The results confirmed the genetic unrelatedness of the strains. Prolonged vancomycin administration, commonly used in hematologic units, could be involved in the selection of endogenous resistant enterococcal strains.

Ribotyping was used to determine whether a relationship exists between endotracheal tube colonisation with Staphylococcus epidermidis and bacteremia with this organism. Over a three-week period, four mechanically ventilated preterm babies presented with five episodes of infection and bacteremia. For each blood specimen obtained for culture a tracheal aspirate sample was collected at the same time by suctioning. After DNA extraction and cleavage by EcoRI, hybridisation was performed with a digoxigenin-labelled 16S-rDNA probe from Escherichia coli. Five different band patterns were recognised on the membrane. In two children the same band pattern was found in Staphylococcus epidermidis isolated from both blood and tracheal aspirate. Ribotyping thus could be used to differentiate a series of infections from an outbreak and showed that a relationship may exist between tracheal colonisation and bacteremia in mechanically ventilated newborns.

Bactericidal activities of ciprofloxacin and sparfloxacin were compared to other antibiotics active against human isolates of Pasteurella multocida. Three human isolates of Pasteurella multocida were used for killing-curve studies with ciprofloxacin and sparfloxacin comparatively to others antibiotics. At 2x the MIC, ciprofloxacin and sparfloxacin exhibited a killing of more than 99.9% of the initial viable cells that was achieved within 6 h of incubation. These activities were faster than those of amoxycillin and cefpodoxime. No regrowth was observed after 24 h of incubation. Doxycycline and clarithromycin used at MICx2 had no bactericidal activities. It was concluded that fluoroquinolones, namely ciprofloxacin and sparfloxacin, can be considered having good bactericidal activity against P. multocida.

The presence of Pasteurella multocida in the oropharynx of 58 pig, cattle or rabbit breeders whose livestock had suffered from pasteurellosis was investigated using a selective medium. Blood samples for serological studies were collected at the same moment. Nineteen breeders were found to host one P multocida subsp multocida strain. Oropharyngeal carriage of P multocida was found to be more frequent in pig breeders (42% of individuals) than in cattle (10%) or rabbit (0%) breeders. Genomic polymorphism among 10 D2 strains was found by restriction endonuclease analysis using pulsed-field gel electrophoresis (REA-PFGE). Antibodies to P multocida were found in the sera of 32 of these 58 breeders, whereas only 2 of the 70 controls had antibodies. These results, recorded from healthy individuals, show that P multocida, acting as an opportunistic bacterium, may be responsible for occupational diseases. Nevertheless, the strong prevalence of specific antibodies makes the presence of antibodies in the sera of these breeders an insufficient indication of a current patent infection.

Out of 900 dialysates analysed over 15 months at the Rennes Regional Hospital, 116 cloudy specimens with a leucocyte count of more than 100/mm3 were studied. Three methods of laboratory diagnosis based on physical or chemical disruption of leucocytes were evaluated: saponin incorporated in the agar medium, sonication, and the Isolator lysis centrifugation system. Sensitivity was improved (52%) for the three methods combined compared with the standard method (37%). The Isolator system (51%, P < 0.05) gave the best results. Direct microscopic examination nevertheless remains essential for its indicative value (sensitivity 33% of positive dialysates). The leucocyte count was correlated with the percentage of culture positivity (43% from 100-200/mm3 compared with 62% from 500-1000/mm3); 80% of organisms were Gram-positive bacteria and most were coagulase-negative staphylococci. Opportunistic pathogens such as Corynebacterium jeikeium were frequently isolated.

The authors report two cases of thoracic actinomycosis with contrasting presentations, just as the diagnosis was obtained by different tests underlying the varied aspects of this disease. Indeed this infectious pathology does infrequently mimic tuberculosis or lung cancer with similar clinical and radiological appearances. The particular characteristic of the bacteriological culture and the quasi specific character of the pale, yellow grains on histology are recalled, as well as the different treatments necessary to ensure a cure in 90% of cases.

This prospective study aimed to determine the prevalence of Helicobacter pylori infection in relation to the occurrence and severity of NSAIDs induced gastropathy. A total of 111 patients were studied-66 were taking NSAIDs and 45 were control patients. All patients underwent endoscopy during which antral biopsy specimens were taken to determine H pylori status (Gram and Giemsa staining, urease test, and cultures). The NSAID group comprised: group I, patients without mucosal damage (n = 28); group II, patients with gastropathy (n = 26); and group III, patients with bleeding associated with NSAID induced gastropathy (n = 12). Control patients had neither dyspeptic symptoms nor endoscopic lesions. There were no differences in age, sex ratio, or presence of H pylori (26% v 24%) between the NSAID and the control groups. Among patients taking NSAIDs, H pylori infection was more frequently (p < 0.02) diagnosed in those who presented with gastropathy (groups II and III: 37%) than in those without lesions (group I: 11%). The frequency of H pylori infection increased significantly with the severity of gastropathy (group I = 11%; group II = 31%; group III = 50%; p < 0.03). H pylori infection was associated with chronic active gastritis (group I = 21%; group II = 35%; group III = 67%; p < 0.05). These data suggest that H pylori may be a risk factor of NSAID induced gastropathy.

Several Pasteurella multocida strains were examined for their ability to produce extracellular enzymes that cleave immunoglobulin A and G (Ig A and Ig G) molecules. Two strains isolated from human pulmonary and genital infections produced proteases that cleaved human IgA and IgG, colostral IgA and human myeloma IgA1 and IgA2. Human IgM was not degraded by these enzymes. Examination of cleavage digests showed two main fragments with different electrophoretic mobilities. The two P. multocida strains produced a protease that cleaved IgA and IgG heavy chains outside the hinge region, and differed in this respect from the hinge-cutting proteases of other bacteria. Protease production may be a virulence mechanism for P. multocida strains.

Ninety-four clinical isolates of Pasteurella multocida of human origin were tested for dermonecrotic toxin (DNT) production by three methods: dermonecrotic test in guinea-pigs, Vero cell culture cytotoxicity and ELISA. The strains were isolated from patients living in a rural area with widespread intensive pig breeding. Six strains were found to be toxigenic by the three tests. A major protein band of Mr 145 Kda corresponding to DNT on immunoblots was demonstrated in extracts from these strains. All were isolated from respiratory tract (diseases 5, healthy carriage 1). The difference between isolates from the respiratory tract and isolates from wounds inflicted by pets was statistically significant with regard to DNT production (p less than 0.02). A possible role of the toxin in pulmonary diseases caused by P. multocida has yet to be established.

A selective culture medium for isolation of Pasteurella multocida was prepared by incorporating 2 mg of amikacin per liter, 4 mg of vancomycin per liter, and 4 mg of amphotericin B per liter into Mueller-Hinton blood agar. Use of this medium revealed the presence of P. multocida in the oropharynges of 19 of the 49 pig breeders who were examined.

An in situ ELISA was performed directly on the adherent cell monolayer in order to determine the susceptibility of herpes simplex virus isolates to acyclovir. Various fixation procedures and antisera conjugated to different enzymes were tested. The use of glutaraldehyde for fixation and beta-galactosidase as a labelling enzyme was shown to give the best results. As with other currently used assays, 50% inhibitory doses were subject to an inoculum effect. The data obtained indicate that this assay is suitable for routine determination of herpes simplex virus susceptibility to antiviral drugs.

A total of 142 Acinetobacter baumanii strains isolated from hospital patients were biotyped according to the scheme of Bouvet and Grimont. Most of the strains belonged to biotype 9 and were highly resistant to antibiotics including cephalosporins and amikacin. Imipenem and ticarcillin were the only drugs having a bactericidal activity against A. baumanii. The combination imipenem-netilmicin and ticarcillin-netilmicin were more rapidly bactericidal than imipenem or ticarcillin alone. No resistant strain to imipenem was isolated.

The authors describe a case of neonatal Proteus mirabilis septicemia accompanied by cerebral abscess formation despite the presence of therapeutically effective antibiotic levels utilised to treat the disorder. The occurrence of such brain abscesses during the course of effective antibiotic therapy raises the question of the mechanism behind their formation. Cerebritis may occur very early in the clinical course of the infection without being due to failure of antimicrobial therapy.

An IV vancomycin treatment induces a reduction of Gram positive cocci (Staphylococcus, Enterococcus) of the aerobic salivary and fecal flora. Some of these strains persisted during and after treatment, but remained susceptible to vancomycin. Others isolated Gram positive cocci were resistant to vancomycin before and after treatment. They were identified as Pediococcus sp., and Leuconostoc sp. There is a reduction of the number of Gram positive cocci, without increase of Gram negative rods, Lactobacillus, or Candida which are always resistant to vancomycin.

Fifty-four clinical isolates of Pasteurella are classified into different taxa. P. multocida subsp.multocida is more frequently encountered than other subspecies of P. multocida. P. canis is only identified from wounds inflicted by animals. The frequency of isolation of different species and subspecies is comparable with that observed from animal isolates. The distribution of the strains in the capsular types is different according to the origin, human or animal, of the strains.

Most of Enterobacter cloacae strains produce chromosomally determined class I beta-lactamases when they are exposed to beta-lactams. Imipenem is a strong inducer of these enzymes but is poorly affected by them. We compared the effect of imipenem on inducible, non-inducible and stably derepressed strains of E. cloacae using the killing curve system. With antibiotic concentrations of 0.5 mg/l or more, an intense dose-dependent bactericidal effect was observed within 4 to 6 hours. However the bactericidal activity was incomplete. With an inoculum as low as 10(5) bacteria/ml a regrowth was observed after 24 hours. Among the surviving bacteria imipenem had the same bactericidal kinetic than on the parental strain. Similar results were observed with inducible, non-inducible and stably derepressed strains.

Exploratory and therapeutic hospital techniques, the frequency of iatrogenic or pathogenic immunodepression and the ever increasing age of the population are factors that augment the risk of nosocomial infections. Some of these infections are unavoidable, but others can be prevented. Appropriate hygienic measures and a rational use of antibiotics contribute to this prevention. We describe here two methods that can be used to watch for nosocomial infections. The one-day recording or prevalence survey method is meant to provide a snapshot image in a given hospital. Longitudinal supervision is more difficult to carry out, but it enables the situation to be more precisely evaluated in each health care centre. Supervision must be regarded as a descriptive stage in the assessment of the local situation as regards the prevalence and incidence of nosocomial infections. It should make it possible to determine priorities in the measures to be taken to prevent most of these infections.

A new case of fatal systemic legionnaires' disease is reported in an infant. This 8 month-old boy was given a protracted treatment with adrenocorticotropic hormones for infantile spasms. Legionella pneumophila type I was found in tracheal secretions and there was multivisceral involvement at autopsy. The mode of contamination and the severity of the disease are discussed in the light of the immunosuppressive properties of the glucocorticoids administered over a period of 4 weeks.

To estimate the rate of infectious diseases and the efficiency of medical care in our hospital, we conducted a prevalence survey of both infections and antibiotic use on 588 inpatients. Results showed that 125 patients (21% of the total) had infections; of these, 56 had nosocomial infections. A third of the patients had been receiving antimicrobial drugs; among them, 30% were receiving the drugs for prophylactic reasons. A misuse in the prophylaxis of infections was determined, particularly in the duration of treatment. The study demonstrated that an effective infection-control program and an antibiotic policy are required in our hospital.