Use of GBS media for rapid detection of group B streptococci in vaginal and rectal swabs from women in labor.

In order to evaluate the differences in efficacy, three methods were used to detect group B streptococci (GBS) in women in labor. The recommended method for detecting GBS carriage in pregnant women is to culture vaginal and anorectal swabs in a selective broth medium and to subculture them onto blood agar. This method was compared with the use of GBS agar and GBS broth, both of which produce an orange pigment in response to GBS strains. A total of 319 women in labor were screened. Among the 638 specimens tested, 134 (21%) were positive in the selective Todd-Hewitt broth subcultured onto sheep blood agar, 133 (20.8%) were positive on the GBS agar and 126 (19.7%) were positive in the GBS broth. Altogether, 89 (27.9%) women in labor were found to be colonized with GBS; 87 (97.8%) of them were identified as carriers using the Todd-Hewitt broth, 87 (97.8%) with the GBS agar and 86 (96.6%) with the GBS broth. These results indicate that both GBS agar and GBS broth are reliable methods that can be used to screen for maternal and neonatal GBS colonization.

Review of the incidence and prognosis of Pseudomonas aeruginosa infections in cancer patients in the 1990s.

In an attempt to determine the actual relevance of Pseudomonas aeruginosa as a target of empiric antimicrobial first-line therapy in febrile cancer patients, 44 reports of clinical trials on antimicrobial treatment regimens and 53 reports on the epidemiology of microbiologically documented infections in cancer patients were reviewed. The incidence of infections due to Pseudomonas aeruginosa was 1-2.5% among all patients presenting with first fever during neutropenia, and 5-12% among patients with microbiologically documented infections. The proportion of Pseudomonas aeruginosa infections among cases of gram-negative bacteremia has not generally declined during the past 2 decades. There were marked local and regional differences regarding the incidence of documented Pseudomonas aeruginosa infections. No clear differences between neutropenic and non-neutropenic cancer patients, between patients with solid tumors and those with hematologic malignancies, or between inpatients and outpatients presenting with fever and neutropenia were detected with respect to the likelihood of Pseudomonas aeruginosa involvement. The mortality rate in patients with Pseudomonas aeruginosa bacteremia, particularly with polymicrobial bacteremia or bacteremic pneumonia with Pseudomonas aeruginosa involvement, is considerably high. The beneficial impact on mortality of an empiric antimicrobial treatment regimen with high antipseudomonal activity has not yet been demonstrated unequivocally. Additional factors such as the quality of intensive care management, effective second-line antimicrobial regimens, local resistance patterns, and patient-related cofactors are very likely to influence the outcome of Pseudomonas aeruginosa infections in cancer patients.

2,4-(hydroxyphenyl)-ethanol, an antioxidative agent produced by Candida spp., impairs neutrophilic yeast killing in vitro.

Culture supernatants of Candida albicans were examined for factors with inhibitory activity against the chemiluminescence of human neutrophils. By high resolution gel chromatography, a low-molecular-mass chemiluminescence inhibitor was isolated. The compound was identified as 2,4-(hydroxyphenyl)-ethanol. Half-maximum inhibition (IC50) of the chemiluminescence response of neutrophils phagocytizing opsonized zymosan or C. albicans occurred at 38.1 +/- 2.3 microM and 19.9 +/- 8.3 microM, respectively. As shown by flow cytometry, the compound protected C. albicans against phagocytic killing (IC50 = 73.8 +/- 16.9 microM). Substantially higher concentrations of the inhibitor were produced by C. albicans and C. tropicalis than by C. parapsilosis and C. glabrata, suggesting a potential role in pathogenicity ranking.

Azithromycin versus cefaclor in the treatment of pediatric patients with acute group A beta-hemolytic streptococcal tonsillopharyngitis.

An open, comparative multicenter study was performed to evaluate the efficacy and safety of azithromycin (10 mg/kg) given once daily for three days in comparison with cefaclor (30 mg/kg) divided into three daily doses and given for a period of ten days. One hundred and twenty-two children aged 1-12 years with clinical symptoms of group A beta-hemolytic streptococcal tonsillopharyngitis and a positive throat culture were randomly allocated to the treatment groups. Overall, the clinical success (cure or improvement) of both regimens was identical in the evaluable patients (86.3%, 44 of 51 patients in either treatment group). In contrast, bacterial eradication after completion of treatment was lower with azithromycin than with cefaclor. Possible reasons for this discrepancy between clinical success and eradication rates could be antibiotic resistance, pre-disease carriage or insufficient dosage. Both agents were well tolerated; only mild or moderate side effects most frequently involving the gastrointestinal tract, were recorded in either therapy group.

[Antibiotic resistance of enterococci in Germany]. / Antibiotikaresistenz der Enterokokken in Deutschland.

BACKGROUND: The resistance of enterococci against various antimicrobial substances including vancomycin has increased markedly. Since 1989 in the USA in particular high resistance rates against vancomycin have been observed but very few surveillance have been published in Europe. Therefore, we conducted a multicenter study in Germany to obtain information about the incidence and distribution of vancomycin and/or high-level aminoglycoside-resistant enterococci. METHODS: A total of 2046 enterococcal isolates were identified and susceptibility-testing was performed according to international guidelines. RESULTS: A total number of 90.5% of the enterococcal isolates were identified as Enterococcus faecalis and 7.8% was Enterococcus faecium. Resistance against ampicillin was detected in 56.6% of the Enterococcus faecium isolates, however, in only one Enterococcus faecalis isolate. High-level resistance against gentamycin or streptomycin was observed in 7.3% and 24.8% of the isolates, respectively. Twelve isolates showed resistance against vancomycin, however, cross resistance with teicoplanin was found in only two isolates. CONCLUSION: The rate of resistance of enterococci in Germany is still considerably lower than in the United States. Previous vancomycin therapy has been implemented as a risk factor for colonization or infection with vancomycin-resistant enterococci. Continued vigilance, decreased use of vancomycin and strict enforcement of infection control measures are appropriate measures to control the growing problem of resistant enterococci.

Increased adherence of Candida albicans to buccal epithelial cells from patients with AIDS.

The adherence of six clinical Candida albicans isolates to buccal epithelial cells obtained from AIDS patients, solid organ transplant recipients and healthy individuals was compared. It was shown that Candida albicans bound in significantly greater numbers to epithelial cells obtained from AIDS patients than to those from healthy individuals or transplant patients, and that the adherence capacity varied among the strains tested.

[Streptococcus B screening with GBS medium in obstetrics]. / B-Streptokokken-Screening mittels GBS-Medium in der Geburtshilfe.

Pregnant women and newborn infants were screened for group B streptococcal (GBS) colonization by obtaining paired swabs from the cervix and urethra for the former group and from the ear, nose, umbilical cord, gastric juice and membranes for the latter. One swab was cultured on blood agar; the other was inoculated into serum-starch broth (GBS medium), which allows identification of GBS by production of a characteristic orange-colored pigment. From the 2105 paired swabs obtained, a total of 158 were GBS positive by either method; of these, 154 (97.5%) were recovered by the GBS medium and 89 (56.3%) by blood agar plate. No false positive color reactions were observed with GBS medium. 75% of the positive GBS media could be read within 24 h of incubation. The use of GBS medium proved to be an easy and reliable method for screening of maternal and neonatal GBS colonization.

[In vitro activity of sparfloxacin against methicillin-resistant staphylococci]. / In-vitro-Aktivität von Sparfloxacin gegen Methicillin-resistente Staphylokokken.

The antimicrobial activity of sparfloxacin (CAS 110871-86-8) against 154 clinical isolates of methicillin-resistant staphylococci was investigated and compared with that of 6 other fluoroquinolones. The isolates consisted of 100 methicillin-resistant Staphylococcus aureus (MRSA), 29 Staphylococcus epidermidis (MRSE) and 25 other coagulase-negative staphylococci (CNS). Sparfloxacin was more active than ciprofloxacin and the other fluoroquinolones against all strains tested. The MIC90 of sparfloxacin against the 100 isolates of Staphylococcus aureus was 8 mg/l, while that of ciprofloxacin was > or = 64 mg/l. Moreover, ciprofloxacin-susceptible MRSA isolates were inhibited by sparfloxacin at a concentration of < or = 0.06 mg/l. The other quinolones had an MIC90 ranging from 0.5 mg/l to 4 mg/l against ciprofloxacin-susceptible MRSA. Similar results were obtained for the MRSE and CNS isolates tested. As many as 90% of the ciprofloxacin-susceptible microorganisms were inhibited at a concentration of < or = 0.06 mg/l or 0.125 mg/l of sparfloxacin. The MIC90 of sparfloxacin against ciprofloxacin-resistant CNS and MRSE were 4 mg/l and 8 mg/l, respectively. Sparfloxacin was clearly more active than any of the other quinolones against all species tested, although higher concentrations were needed to inhibit ciprofloxacin-resistant staphylococci.

[Comparative antibacterial activity of cefpodoxime against Haemophilus influenzae, Streptococcus pyogenes, Streptococcus pneumoniae and Moraxella catarrhalis]. / Vergleichende antibakterielle Aktivität von Cefpodoxim gegen Haemophilus influenzae, Streptococcus pyogenes, Streptococcus pneumoniae und Moraxella catarrhalis.

The antimicrobial activity of cefpodoxime (Podomexef, CAS 80210-62-4) against 236 clinical isolates of H. influenzae, Moraxella catarrhalis, Streptococcus pyogenes and Streptococcus pneumoniae was investigated and compared with that of another 8 commonly used oral antibiotics. beta-Lactamase negative, beta-lactamase positive and multiresistant strains of H. influenzae were inhibited by cefpodoxime at a concentration of 0.13 mg/l. 10% of Moraxella catarrhalis isolates were moderately susceptible to cefpodoxime, with minimum inhibitory concentration (MIC) of cefpodoxime ranging between 0.13 and 2.0 mg/l. All isolates of Streptococcus pyogenes and Streptococcus pneumoniae were susceptible to < or = 0.25 mg/l cefpodoxime. Cefpodoxime was clearly more active than the older oral cephalosporins against all species tested. The activity was comparable to that of cefixime against all species except Streptococcus pneumoniae, against which cefpodoxime was more active than cefixime.

Methicillin-resistant Staphylococcus aureus in Europe.

In order to obtain pan-European data on methicillin-resistant Staphylococcus aureus (MRSA), 43 laboratories from ten European countries each screened 200 consecutive Staphylococcus aureus isolates for methicillin resistance. Only one isolate per patient was permitted. All participants used a uniform oxacillin-supplemented screening plate. MRSA isolates were sent to Munich for reconfirmation and further susceptibility testing. Phage typing of the MRSA strains was performed in Denmark. Of the 7,333 Staphylococcus aureus strains screened, 936 (12.8%) were methicillin resistant. The proportion of MRSA in the various European countries ranged from < 1% in Scandinavia to > 30% in Spain, France and Italy. Rates of resistance to the non-glycopeptide antibiotics were lowest for rifampin and highest for ciprofloxacin. Sixty percent of the methicillin-resistant strains originated from patients in surgical and medical departments, with wounds being the most common isolation source. MRSA was found more frequently in intensive care patients. Only 13% of the strains were non-typable, and 76% of the isolates belonged to phage group III. For each area phage typing detected one or a few dominating (epidemic) types, but 46% of the strains did not belong to these types; the MRSA population is thus a mixture of epidemic and non-epidemic strains. MRSA seems to be a growing problem, especially in southern Europe, where incidence and rates of antibiotic resistance are alarmingly high.

[Evaluation of the serum bactericidal test]. / Bewertung des Serumbakterizidie-Tests.

The serum bactericidal test (SBT) is used to monitor antibiotic treatment during therapy. Compared to other methods of sensitivity testing, such as MIC (minimum inhibitory concentration) determination, the SBT also takes into consideration the pharmacokinetic qualities of the drug tested. Serum bactericidal titers are measured during therapy of different infectious diseases to estimate therapeutic outcome. Until now serum bactericidal titers of 1:8 in non-granulocytopenic patients, and titers > or = 1:16 in granulocytopenic patients have been shown to correlate with a successful treatment outcome in patients with gram-negative sepsis. In patients with endocarditis a peak serum bactericidal titer of at least 1:32 should be achieved. Another way to apply the serum bactericidal test is to compare the activity of different antibiotics in volunteers. The present study as well as data from the literature indicate that ciprofloxacin has markedly higher serum bactericidal activity than ofloxacin. Of the so called "basic cephalosporins" cefotiam achieved the highest serum bactericidal activity against the Enterobacteriaceae tested. Since 3rd generation cephalosporins are in general highly active against gram-negative rods, we were interested in using the SBT to compare different dosage regimens. In several studies serum bactericidal titers of > or = 1:8 were achieved with the 1 g dosis of cefotaxime, cefmenoxime and especially ceftazidime against the gram-negative rods tested.

[Quantitative study of vaginal flora during the menstrual cycle]. / Quantitative Untersuchung der Vaginalflora im Verlauf des Menstruationszyklus.

The aerobic and facultatively anaerobic vaginal flora of 242 healthy women were examined during menstrual cycles. The most frequently isolated microorganisms at the first premenstrual examination were coagulase-negative staphylococci (61%), followed by enterococci (25%), Gardnerella vaginalis (19%), diphtheroids (12%), group B streptococci (6.8%), Escherichia coli (5.4%) and Candida spp. (4%). The isolation rate of all species, except Candida and Gardnerella vaginalis increased during menstruation. The lowest isolation rate for Staphylococcus aureus was 0.9% prior to menstruation and it increased to 7.6% during menstruation. This may be of relevance with regard to the toxic shock syndrome. Gardnerella vaginalis was isolated in 37% of women at least once during the study, suggesting, that this species belongs to the normal vaginal flora.

[Evaluation of the so-called basic cephalosporins using the serum bactericidal test]. / Beurteilung der sogenannten Basiscephalosporine anhand des Serumbakterizidietests.

The serum bactericidal activity (SBA) was studied one hour and four hours after intravenous administration of 1 g and 2 g cefotiam, 1.5 g cefuroxime and 2 g cefazolin to six volunteers. The 136 clinical isolates tested included Staphylococcus aureus, Staphylococcus epidermidis, Escherichia coli, Klebsiella pneumoniae, Proteus mirabilis and Haemophilus influenzae. One hour after administration no significant differences in the activity against staphylococci were noted in the antibiotics tested. Four hours after administration of cefazolin 96% of the Staphylococcus aureus strains were killed at a serum dilution of 1:8, whereas only one strain was killed by cefuroxime and none by cefotiam under the same conditions. The highest SBA-titers against Haemophilus influenzae were achieved with cefotiam at a dosage of 2 g. SBA-titers against Escherichia coli, Klebsiella pneumoniae and Proteus mirabilis were higher after administration of 1 g cefotiam than after administration of 1.5 g cefuroxime and 2 g cefazolin, respectively.

[Prospective, comparative study of a infrared spectroscopic blood culture system (Bactec NR-660)]. / Prospektive, vergleichende Untersuchung mit einem Infrarot-Spektroskopie-Blutkultursystem (Bactec NR-660).

The automatic Bactec NR-660 system was compared with a conventional blood culture system - Septi-Check, La Roche (RSC). Out of a total of 962 blood cultures 157 isolates were detected: 123 in RSC and 104 in Bactec 6A. If only clinical relevant strains were considered the isolation rate was nearly equal in both systems, being 75% in RSC and 77% in Bactec 6A, respectively. The RSC-system was more frequently contaminated (3.3% vs 1.0%). Positive blood cultures were detected 12 hrs earlier by the Bactec system.

[In-vitro activity of enoxacin: a multicenter study]. / In vitro-Aktivität von Enoxacin: Eine multizentrische Studie.

The in vitro activity of enoxacin was tested in 14 German microbiological centers shortly after the introduction of the drug in Germany. 2748 unselected clinical isolates including 15 bacterial species were analysed using microtiter plates. The MIC90-values were as follows: Staphylococcus aureus 4 mg/l, Enterococcus faecalis 16 mg/l, Enterobacteriaceae 0.5 mg/l, Pseudomonas aeruginosa 8 mg/l. There is good correlation between these results and those of former investigations. It is known that quinolones are only moderately active against enterococci. 8.5% of S. aureus, and 1.4% of Enterobacteriaceae were found to be resistant (MIC greater than 4 mg/l). As to P. aeruginosa, the study revealed that despite a generally low rate of resistance in specific clinical settings, specific problems can arise: in one institution, the MIC90 of P. aeruginosa was 32 mg/l, with a resistance rate of 56.1% (n = 57). In the other centers the MIC90 was 2 mg/l and the resistance rate 5.0% (n = 302). In the first center, many of the isolates were from paraplegic patients or patients with cystic fibrosis pretreated with quinolones. This study will be repeated in two years' time in order to determine an eventual change in resistance.

In vitro activity of new antibiotics against Haemophilus influenzae.

The activity of sulbactam/ampicillin, aztreonam, cefetamet, cefixime, ciprofloxacin, enoxacin, fleroxacin and ofloxacin was determined against 160 Haemophilus influenzae strains using a standardized microdilution method. The strains were categorized into four groups according to beta-lactamase production and their resistance to ampicillin, chloramphenicol, erythromycin, tetracycline and cotrimoxazole. All isolates tested, regardless of their beta-lactamase production or resistance to the above mentioned drugs, were susceptible to the nine antibiotics. The most active antimicrobial agents were aztreonam, cefixime, and the two quinolone derivatives ciprofloxacin and ofloxacin.