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I Phillips

Publications and source records attributed to I Phillips.

At least 163 records · Page 9Linked to original sources
PubMed1988

European collaborative study of reproducibility of quantitative sensitivity testing of anaerobes.

Minimum inhibitory concentrations (MICs) of ampicillin, cefoxitin, cefbuperazone, latamoxef, metronidazole, clindamycin and chloramphenicol were determined for 15 different anaerobic bacteria including Bacteroides spp., anaerobic cocci and Clostridium spp., in 18 European laboratories, who used their own methodology. The degree of intra- and inter-laboratory reproducibility was surprisingly good--87% of results fell on the modal MIC or were within one dilution of it and only 4.4% of the results differed by three or more dilutions. Results for clindamycin were the least reproducible, as were those for clostridia. Of the organisms that we tested Bacteroides fragilis ATCC 25285, NCTC 9343 emerged as the most suitable for use in quality control, and Peptococcus variabilis ATCC 14956 the most appropriate if a control for more slowly-growing species is required.

Ampicillin↗
PubMed1988

Epidemic methicillin-resistant Staphylococcus aureus.

We contrast the experiences, in our Health Authority in South-East London, with the particular epidemic methicillin-resistant Staphylococcus aureus (the EMRSA) strain that has recently spread widely around London and South-East England, and with the other MRSA (OMRSA) strains encountered there. Our isolates of the EMRSA were identical by chromosomal restriction enzyme analysis, and the chromosomal and plasmid phenotypes were similar to those described in North London and Eastern Australia. Experimental phage-typing distinguished them from OMRSA encountered in 1984 to 1986. Between 1984 and 1985, the EMRSA caused increased infection and patient colonization compared to the years 1969 to 1983. A change in infection control procedures was usually required to control the EMRSA and in 1986 isolates had returned to their pre-1984 levels. Between 1984 and 1986 OMRSA were still encountered, but did not spread or require changes in infection control procedures. The distribution of other resistant isolates was examined; c 94% of neomycin-resistant isolates were in-patients or clinic patients. Forty-five different phage-type/antibiogram patterns were found in 88 isolates from 66 patients between 1982 and 1985, and patient clusters were uncommon. The ability of the EMRSA to spread is discussed and is probably not purely organism related. Our experience supports the contention that some MRSA are truly epidemic, whilst others do not behave in this manner.

Humans↗
PubMed1988

The in-vitro activity of PD127,391, a new quinolone.

MICs of PD127,391 a new 4-quinolone, and of CI934 and ciprofloxacin, two previously reported 4-quinolones, were determined for common clinical bacterial isolates by an agar-dilution method. PD127,391 was the most active drug against Enterobacteriaceae and Acinetobacter spp (MICs less than 0.12 mg/l) and as active as ciprofloxacin against Aeromonas spp. (MICs less than 0.008 mg/l) and Pseudomonas aeruginosa (MICs less than 1 mg/l). It was more active than ciprofloxacin against Pseudomonas spp. including Ps. maltophilia (MICs less than 0.25 mg/l). All three drugs had high activity, with PD129,391 again the best, against Haemophilus influenzae Brahmamella catarrhalis, and Neisseria gonorrhoeae. PD127,391 was much more active than the other drugs against Campylobacter coli/jejuni (PD127,391 MICs less than 0.03 mg/l) and Gardnerella vaginalis (PD127,391 MICs less than 0.25 mg/l). PD127,391 inhibited all staphylococci at less than 0.06 mg/l and streptococci at less than 0.5 mg/l, thus being more active than CI934 or ciprofloxacin. PD127,391 was much more active against anaerobic cocci, Bacteroides spp. and clostridia (including Clostridium difficile) (MICs less than 1 mg/l) than was CI934 (MICs less than 16 mg/l) or ciprofloxacin (MICs less than 64 mg/l). No bacterium that we examined required more than 1 mg/l of PD127,391 for inhibition, and there was no cross resistance with unrelated antibiotics.

Anti-Infective Agents↗
PubMed1988

Laboratory diagnosis of peritonitis in patients on continuous ambulatory peritoneal dialysis.

The clinical course and laboratory diagnosis of peritonitis in patients undergoing continuous ambulatory peritoneal dialysis was studied in 32 consecutive episodes. Peritonitis was associated with a failure in aseptic technique in eight episodes and with an exit-site infection in four episodes. Intraperitoneal vancomycin and ceftazidime were safe, effective, and convenient. Most patients administered their antibiotics at home, and symptoms usually resolved by day 4. Culture of the deposit obtained by centrifugation of 50 ml of effluent after leukocyte lysis provided the best rate of recovery (84% culture positive) but was technically demanding. Filtration of the same volume without leukocyte lysis was simple to perform and almost as effective. Enrichment was less satisfactory (65% culture positive) owing to the presence of antibiotic or infection with fastidious microorganisms. Culture of 50 ml of effluent after concentration by a commonly used laboratory technique, centrifugation without leukocyte lysis, performed poorly (59% culture positive at 48 h), as this method caused sequestration and death of microorganisms within the leukocytes. Culture of nearly 1 liter of effluent from 33 asymptomatic patients by the same techniques yielded no microorganisms.

Bacteria↗
PubMed1987

Carriage of gentamicin-resistant coagulase-negative staphylococci in patients on continuous ambulatory peritoneal dialysis.

Gentamicin-resistant coagulase-negative staphylococci were found on various sites of the skin of 20 of 27 patients on continuous ambulatory peritoneal dialysis (CAPD). In 12 cases isolates with identical susceptibility patterns could be recovered from the same patients at intervals of 2-8 weeks. In seven of these cases isolates from individuals repeatedly had the same phage type, biotype and plasmid profile and three patients shared such identical strains. The use of plasmid profiles proved to be most satisfactory for epidemiological purposes. It was concluded that out-patients on CAPD may persistently harbour their own gentamicin-resistant coagulase-negative staphylococcal strain and that cross-colonization may also occur.

Coagulase↗
PubMed1987

The antibiotic sensitivity of the Bacteroides fragilis group in the United Kingdom.

Eight hundred and sixty-two cultures of penicillin-resistant anaerobic Gram-negative bacilli collected from 14 centres in the United Kingdom were identified. Six hundred and fifty-one were members of the Bacteroides fragilis group, and their sensitivity to 14 antibiotics was determined by a microtitre method. Among the beta-lactams, moderate resistance to ampicillin (MIC greater than or equal to 8 mg/l) was common, (B. ovatus 100%, B. thetaiotaomicron 95%, B. fragilis 76%, B. distasonis 50%, B. vulgatus 25%) but high-level resistance (MIC greater than 128 mg/l) was uncommon (B. fragilis 4%, B. ovatus 4%, B. vulgatus 3%). In B. fragilis, moderate resistance to other beta-lactams was less common (cefoxitin 16%, mezlocillin 13% and cefotetan 7%), though in most non-B. fragilis species, higher numbers were moderately resistant. High level resistance to these three beta-lactams was rare. Resistance to penems (MIC greater than 4 mg/l) was not detected. All isolates of B. fragilis tested were sensitive to 16 mg/l of ciprofloxacin and ofloxacin, and 68% and 81% of isolates were sensitive to less than 4 mg/l, but one isolate of B. uniformis and one of B. thetaiotaomicron proved highly resistant. Clindamycin resistance was uncommon (1% of B. fragilis and 10% other B. fragilis group isolates were resistant to 2 mg/l clindamycin) with isolates resistant to clindamycin often also resistant to erythromycin. Tetracycline resistance was common in all species and occurred in 40% of isolates. Resistance to chloramphenicol, metronidazole or rifampicin was not detected. Significant differences were observed between the sensitivity of B. fragilis and other members of the B. fragilis group to mezlocillin, cefotetan, cefoxitin and the quinolones. There was no clear trend towards higher resistance in any one area of the country.

Anti-Bacterial Agents↗
PubMed1987

Induction of the SOS response by new 4-quinolones.

The 4-quinolones ciprofloxacin, difloxacin, enoxacin, norfloxacin, ofloxacin, and nalidixic acid were found to induce the SOS response in qualitative and quantitative tests on Escherichia coli K12 containing the sfiA::lacZ gene fusion. Maximum induction of the SOS-response was observed with the quinolone concentrations that produced the most killing. There was also a modest increase in the rate of mutation in the lactose and galactose operons in a GalE- background, provided there was a functioning SOS system.

DNA Repair↗
PubMed1987

Role of cephalosporins in gonorrhoea and other sexually transmitted diseases.

Cephalosporins have a role in the treatment of gonorrhoea, and especially infections caused by strains that are penicillin-resistant, either because they produce plasmid-mediated beta-lactamase or they have chromosomally mediated diminished permeability or modified penicillin-binding proteins. Although none of the oral or Group I agents are useful, most of the Group II, III and IV agents are, and especially cefuroxime, cefotaxime, ceftriaxone and cefoxitin. In addition to uncomplicated urethral, cervical or rectal infections, appropriate regimens are also effective for the treatment of pharyngeal infections, disseminated infections and gonococcal ophthalmia. The cephalosporins have no clear role in the treatment of syphilis, granuloma inguinale, Mycoplasma or chlamydial infections or bacterial vaginosis, but ceftriaxone may be effective in chancroid, and cefoxitin in combination with an antichlamydial agent (such as a tetracycline) might be used for the treatment of pelvic inflammatory disease.

Cephalosporins↗
PubMed1987

The in-vitro activity of roxithromycin, a new macrolide antibiotic, in comparison with that of erythromycin.

A study was made of the in-vitro activity of roxithromycin in comparison with that of erythromycin on selected recent clinical isolates of a wide range of organisms. Minimum inhibitory concentrations (MICs) were determined by an agar dilution method with an inoculum of 10(4) cfu. Minimum bactericidal concentrations (MBCs) and the effect of pH were determined by a broth dilution method on selected strains. In general the in-vitro activity of roxithromycin mirrored that of erythromycin, but it was slightly less active. Most strains of streptococci, with the exception of enterococci, were highly sensitive to roxithromycin, as were isolates of Gardnerella vaginalis. Branhamella catarrhalis and Neisseria gonorrhoeae. Staphylococci and enterococci were only moderately sensitive to both agents as was Haemophilus influenzae. Most anaerobic bacteria were sensitive although Bacteroides fragilis, fusobacteria and some strains of some clostridial species were moderately resistant. The MBCs were usually at least 16-fold higher than MICs for most staphylococci, enterococci, alpha-haemolytic streptococci and B. fragilis; but for beta-haemolytic streptococci, pneumococci, H. influenzae and B. catarrhalis the MBCs were usually only 2- to 4-fold higher than MICs. Roxithromycin was most active at pH 8 and generally for each unit fall in pH there was a 4-fold diminution of activity. However, the effect was less marked for pneumococci, beta-haemolytic streptococci and H. influenzae.

Anti-Bacterial Agents↗
PubMed1986

Prevalence and mechanisms of aminoglycoside resistance. A ten-year study.

Aminoglycoside resistance was monitored at St. Thomas' Hospital from 1975 to 1984. Gentamicin resistance had appeared in a number of species by 1975, but remained rare (less than 1 percent of isolates) in Escherichia coli throughout the study period. Gentamicin-resistant Klebsielleae had become fairly common (8 percent of isolates) by 1977, but little change has subsequently occurred in their frequency of isolation. Serratia species are not frequently isolated; gentamicin resistance in these organisms was not observed until 1979. Since then, 10 to 20 percent of isolates have been found to be resistant. Except for Providencia, most isolates of which were gentamicin-resistant, less than 5 percent of the Enterobacteriaceae isolated were found to be resistant to gentamicin during the 10-year period. Throughout the study, approximately 5 percent of the Pseudomonas aeruginosa isolates were resistant to gentamicin. Less than 5 percent of the isolates of Acinetobacter were resistant to gentamicin before 1979, at which time 40 percent were found to be resistant; subsequently, gentamicin resistance among these organisms has become somewhat less common. On the whole, tobramycin resistance has mirrored gentamicin resistance. However, before 1979, most gentamicin-resistant Klebsielleae isolates had retained susceptibility to tobramycin, as had most gentamicin-resistant isolates of Acinetobacter and P. aeruginosa. Amikacin resistance has remained very unusual in all organisms, apart from non-aeruginosa Pseudomonas species. Until 1977, nearly all the resistance among Enterobacteriaceae was attributable to AAC(3)-I, except for that caused by AAC(2') production in Providencia and the non-enzymatic resistance observed in E. coli. However, more recently, AAC(3)-II and AAD(2'') have become the most common mechanisms of resistance. The resistance of most gentamicin-resistant isolates of P. aeruginosa from 1974 to 1977 was attributable to non-enzymatic mechanisms; subsequently, such resistance was more often caused by AAC(3)-I, AAC(6'), or AAD(2''). Gentamicin resistance first appeared in Staphylococcus aureus in 1976, after which about 1 to 2 percent of the isolates from hospitalized patients were found to be resistant, mostly because of production of AAC(6') and APH(2'').

Acinetobacter↗