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BACKGROUND: Respiratory tract infections (RTI) are frequently caused by Haemophilus influenzae. Widespread antibacterial resistance among respiratory microorganisms complicates empirical RTI treatment. Therefore, national data on antibiotic resistance for H. influenzae are important for guiding optimal antibiotic choice. METHODS: The antibiotic susceptibility of H. influenzae strains isolated from respiratory specimens of patients admitted to the pulmonology services between 2005 and 2010 was assessed. Isolates were collected annually from 13 hospitals in the Netherlands as part of the national intramural antimicrobial resistance surveillance performed by the Dutch Working Group on Antibiotic Policy (SWAB). Breakpoints for resistance were in accordance with the criteria of the European Committee on Antimicrobial Susceptibility Testing (EUCAST). Trend analysis was performed using logistic regression analysis. RESULTS: In total, 1606 H. influenzae strains were analyzed. The prevalence of antibiotic resistance to amoxicillin, co-amoxiclav, doxycycline, co-trimoxazole, and clarithromycin was stable over the 6-y period, and there was a trend towards a decrease in the prevalence of beta-lactamase-producing isolates. Regarding prevalences, no significant trends were observed. CONCLUSIONS: Our study showed no significant changes in antibiotic resistance for H. influenzae isolated at different hospitals in the Netherlands over a 6-y period. Regular surveillance remains important in controlling the prevalence of resistance, since actual resistance data should be taken into account when the choice of an empiric antibiotic is made.

An increase in antibiotic resistance of Escherichia coli, the most common pathogen in urinary tract infections (UTIs), is encountered worldwide. Optimal treatment of UTIs will contribute substantially to limit antibiotic use and antimicrobial resistance. This study determined trends in antimicrobial resistance of uropathogenic E. coli, which can be of use to optimize UTI guidelines.During 1998-2005, E. coli from urine samples of patients attending urology services were collected in three regions in The Netherlands: north-east (NE, n = 1084), west (W, n = 1064) and south (S, n = 1212). The antibiotic susceptibility was determined using microbroth dilution following CLSI guidelines. E. coli ATCC 35218 and ATCC 25922 were used as reference strains.Amoxicillin resistance remained stable over time (37% to 47%), but was higher in the south (44%) compared with the other regions (40%; P0.02). Resistance to piperacillin increased from 4% (1998) to 32% (2005; P0.001), and resistance to fluoroquinolones increased from 6% to 13% (P0.01). Interregional differences were observed for resistance to piperacillin (NE 10%, W 12%, S 14%; P0.05) and to fluoroquinolones (NE 7%, W 13%, S 8%; P0.001). Trimethoprim +/- sulfamethoxazole resistance remained stable (27% to 37%), as did that of nitrofurantoin (4% to 9%). The percentage of strains with multidrug resistance (resistance to three or more groups of antibiotics) for each region increased over time (P0.05).Antibiotic resistance was fairly constant over time for most agents tested, except for piperacillin and the fluoroquinolones. Regional differences were observed for several compounds. National and regional surveillance of antibiotic resistance is important to keep therapeutic guidelines up-to-date and adequate for the treatment of resistant microorganisms.

Objective:Group B streptococcus (GBS,Streptococcus agalactiae) is an important cause of neonatal sepsis. Prevention is possible by intrapartum screening for maternal GBS carriership and antimicrobial treatment of colonized women with risk factors during labor. The conflicting results of diagnostic performance are reported both for the newly developed rapid GBS antigen tests and Gram's stain.Methods:The value of Gram's stain in GBS screening was investigated prospectively in 1,020 women. Intrapartum Gram's stains of the cervix from these women and of the introitus from 510 of them were compared with cultures of the cervix, introitus, and anorectum in a semiquantitative way.Results:The sensitivities of the cervical and introital Gram's stains were 25% and 31%, respectively, and the specificities 99% and 98%, respectively. Higher sensitivities (52% and 44%, respectively) were found in heavily colonized parturients. No significant influence of rupture of the membranes was detected. There was a poor correlation between the number of gram-positive cocci in the Gram's stain and the growth density.Conclusions:We do not recommend the routine use of the Gram's stain for intrapartum GBS detection because of both the limited sensitivity and positive predictive value.

Vaginal, cervical, and rectal swabs were obtained from 762 women early in pregnancy to culture group B streptococci (GBS). The overall carrier rate was 13.9% and the rectal, vaginal, and cervical carrier rates were 10.6%, 7.9%, and 6.3%, respectively, GBS were isolated only from the rectum in 33%, so the rectum is an important reservoir. Seventy-five percent of the culture-positive women were permanent or intermittent carriers. Ninety percent of all women positive at labor were positive before the 20th week; acquisition of GBS late in pregnancy was rare. The frequency of transmission to the neonates was 63.4% among permanent carriers. Other determinants for transmission were the number of positive sites, the heaviness of colonization, and the (cervical) localization of GBS at labor. The serotypes of GBS isolated from the mothers and neonates were the same. Serotype distribution fluctuated during pregnancy. Types III (29%) and Ib (27%) were predominant, followed by types II (12%) and Ic (10%).

The effect of iron deprivation on growth of 101 aerobic strains of gram-positive and gram-negative bacteria was studied on agar media in the presence of various concentrations of the synthetic iron chelator ethylene diamine diorthohydroxyphenyl acetic acid (EDDA) and the iron binding protein transferrin. Growth of Staphylococcus epidermidis was inhibited by 15 mM EDDA and 1.5 mM transferrin. Staphylococcus aureus was only inhibited by 44 mM EDDA and not by transferrin. None of the strains of S. faecalis was inhibited. The majority of the enterobacteriaceae (E. coli, Salmonella spp, Klebsiella spp) was inhibited by 44 mM EDDA and 1.5 mM transferrin. The relation between susceptibility and concentration of EDDA and transferrin was expressed as S-value for each species. Iron supply with various iron compounds could restore the effects of inhibition. In all species except in S. faecalis iron chelator production could be demonstrated, using indicator plates of media containing EDDA and flooded with 10(4)--10(5) colony forming units of indicator organisms. The iron chelator of both S. epidermidis and S. aureus could stimulate growth of S. epidermidis, but not that of enterobacteriaceae. Iron chelators from all gram-negative bacteria were functionally interchangeable, but did not stimulate growth of gram-positive bacteria.

Longitudinal quantitative cultures of fecal flora of 20 newborns, 4 older babies and 10 healthy adults were carried out to study the composition and development of the intestinal flora. In all newborns the same sequence of colonization was observed. The numbers of aerobic and anaerobic bacteria fluctuated and reached finally numbers of 10(10)/g wet weight. In adults the flora was in balance with 10(5)-10(7) aerobic and 10(10)-10(11) anaerobic bacteria/g wet weight. Interaction experiments in vitro showed growth inhibition of Bacteroides fragilis by all intestinal species isolated. Bifidobacteria were not inhibited. The assumption was made that this type of interaction could be one of the mechanisms involved in the intestinal micro-ecology. Three of the Bacteroides fragilis strains tested were able to grow on "natural intestinal substrates" as gastric mucin, glycogen and a variety of plant polysaccharides. Acetic, lactic, propionic and succinic acids were detected as fermentation products.

SUMMARY The cervical and high vaginal flora were studied by quantitative culture methods applied to 356 specimens from 53 healthy non-pregnant women, 102 pregnant women and 57 women with cervicitis. Specimens were obtained with a specially designed “slimesucker”. In all groups the total viable counts ranged from 108-1010 bacteria per ml of fluid from the cervix and posterior fornix. There was only a slight difference between the flora of cervix and fornix. In healthy women the means of the number of bacterial species per cervical and high vaginal specimen were 1·5 and 1·9 respectively. Lactobacilli predominated in 72% and 80% of cervical and high vaginal cultures respectively. Staphylococcus albus, non-haemolytic and α-haemolytic streptococci, diph-theroids, peptostreptococci, peptococci and Bacteroides spp. could be isolated in high numbers, but less commonly than lactobacilli. Members of the Enterobacteriaceae and yeasts also occurred less commonly than lactobacilli, and in lower numbers (105-108 organisms per ml). It is postulated that the Enterobacteriaceae and yeasts are not part of the normal flora. In specimens from pregnant women the viable bacterial counts were comparable with those in specimens from healthy non-pregnant women. The flora was even more homogeneous during pregnancy, the means of the number of species being 1·5 and 1·7 in cervical and high vaginal cultures respectively; lactobacilli occurred in 92% of the cervical and 86% of the high vaginal samples. In women with cervicitis the means of the number of species obtained from the cervix and fornix were 2·2 and 2·5, with lactobacilli predominating in 65% and 84% respectively. Bacteroides spp. and peptostreptococci were more commonly encountered in women with cervicitis than in those without, but the viable counts of these organisms were similar in all women. The role of bacteria in the production of cervicitis is discussed.

Summary: Formation of iodophilic polysaccharide (IPS) from glucose was demonstrated in 27 strains of Bacteroides fragilis. Synthesis was dependent on the glucose concentration of the medium, the pH and the growth phase. When glucose was in short supply the cellular polysaccharide was degraded rapidly at pH 4.5 to 6.5 and fatty acids accumulated in the medium. Storage of IPS was not responsible for the low carbon recoveries observed in fermentation balance studies. In electron micrographs of thin sections, the IPS was observed as cytoplasmic granules dispersed throughout the whole cell. After extraction and purification the IPS was characterized as a glycogen.