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J Turnidge

Publications and source records attributed to J Turnidge.

At least 37 records · Page 2Linked to original sources
PubMed1995

Validation of a modified Kirby-Bauer disk diffusion method for metronidazole susceptibility testing of Helicobacter pylori.

Triple antimicrobial therapy that includes metronidazole has been recommended as a first-line therapy for Helicobacter pylori because it has the highest eradication rates. However, resistance in H. pylori to metronidazole has been reported worldwide and its presence may reduce the efficacy of triple therapy. Various methods for testing H. pylori against metronidazole have been used including agar dilution, disk diffusion and the Etest but there has been little standardization of methods. One hundred isolates of H. pylori from different patients were tested for susceptibility to metronidazole by agar dilution, Etest and disk diffusion (5 micrograms disk). The agar dilution results confirmed the MIC susceptibility breakpoint to be < or = 8 micrograms/ml. Using this breakpoint there was close agreement (98%) between Etest and agar dilution results. For susceptible strains, MICs by E-test were generally one twofold dilution lower. Using the error-rate bounded method, agreement between disk diffusion zone diameter and MIC was 98% for agar dilution with breakpoints of > or = 12 mm and < or = 8 micrograms/ml and 100% for Etest with breakpoints of > or = 12 mm and < or = 8 micrograms/ml. The Etest discriminated better than agar dilution between susceptible and resistant strains and was simple to perform. The disk diffusion test is a reliable and cheaper alternative to the Etest with susceptibility being a zone diameter > or = 12 mm with a 5 micrograms disk. The prevalence of metronidazole resistance in this study was 40% by Etest.

Diffusion↗
PubMed1995

Random amplified polymorphic DNA and plasmid analyses used in investigation of an outbreak of multiresistant Klebsiella pneumoniae.

Multiresistant Klebsiella pneumoniae strains with plasmid-borne extended-spectrum beta-lactamases (ESBL) are increasingly frequent nosocomial pathogens. A major outbreak of clinical infections, mainly involving patients in the Newborn Services Unit with limited spread to adult patients, occurred at our hospital. This epidemic was investigated by typing the isolates phenotypically and with random amplified polymorphic DNA analysis (RAPD) and plasmid analysis. Forty-eight isolates, consisting of 44 consecutive clinical isolates and 4 selected surveillance isolates, were studied. A single decamer primer was used for the RAPD, and this was effective in demonstrating that the majority of isolates (45 of 48) had the same profile. Three other isolates had different RAPD patterns identifying them as nonepidemic strains. Plasmids were extracted by alkaline lysis with Magic-miniprep kits from 10 isolates selected to represent the epidemic and nonepidemic strains. This method produced small (< 20-kb) plasmids; larger ESBL-carrying plasmids were not produced, but the small plasmids nonetheless allowed strain differentiation. Antibiotic susceptibility patterns alone were not reliable as strain indicators, since some isolates with the RAPD pattern characteristic of the epidemic strains did not express ESBL and therefore were susceptible to extended-spectrum cephalosporins. The investigation showed the predominance of a single epidemic strain that was transmitted between patients in the Newborn Services Unit. RAPD was the best of the methods used for detecting strain differences, and its speed and ability to type a wide variety of species suggest that it will be an increasingly useful molecular epidemiologic tool.

Adult↗
PubMed1995

Epidemiology of quinolone resistance. Eastern hemisphere.

Both nalidixic acid and fluoroquinolones are used widely in the Eastern hemisphere for a variety of infectious diseases. A surveillance programme for antibiotic resistance in common pathogens has been conducted in the Western Pacific Region of the World Health Organization since 1989. Data on resistance to fluoroquinolones for the years 1992 and 1993 from the 16 participating countries in the Western Pacific, plus published data from Thailand, were collated for common and important pathogens in this region. Overall, fluoroquinolone resistance levels were highest in developing countries and lowest in developed countries, with transitional countries undergoing rapid economic improvement showing intermediate levels of resistance. There was also a trend towards increasing levels of fluoroquinolone resistance between 1992 and 1993. In developed countries, levels of resistance to fluoroquinolones exceeded 10% for only Pseudomonas aeruginosa, Staphylococcus aureus, and Acinetobacter and Providencia species. Resistance levels of 25% or more in Escherichia coli were noted in 3 countries in 1993. In contrast, resistant strains of Salmonella typhi and S. paratyphi A were rare or nonexistent in any country, and only low levels of resistance were detected in Shigella species. Fluoroquinolone resistance appears to be emerging slowly in developed countries and more rapidly in transitional and developing countries. Strenuous efforts will be required in some countries in order to prevent the early obsolescence of these valuable agents.

4-Quinolones↗
PubMed1994

Cerebral sparganosis in an East Timorese refugee.

OBJECTIVE: To report the first case of cerebral sparganosis diagnosed in Australia. CLINICAL FEATURES: A 23-year-old East Timorese refugee, whose diet before migration included raw snakes and frogs, presented with a generalised tonic-clonic seizure and a nine-month history of episodic left hemianaesthesia. Computerised axial tomography of the brain showed a right frontal lesion, which was excised, and histological examination demonstrated changes typical of sparganosis. INTERVENTION AND OUTCOME: Excision of the lesion resulted in cure. Postoperative eosinophilia and a subcutaneous nodule presumed to be due to disseminated sparganosis resolved following a course of praziquantel. CONCLUSION: Clinicians should consider the possibility of unusual parasitic infections in refugees who present with intracranial space-occupying lesions, especially those from developing countries. A dietary history may aid the diagnosis.

Adult↗
PubMed1994

Pitfalls in antibiotic prescribing and how to avoid them.

Errors in antibiotic prescribing occur due to either a failure to understand basic antibiotic prescribing principles or through incorrect management decisions. The most common example of the former is prescribing antibiotics when they are not needed and the most common management error is failing to investigate prior to treatment. Other common management errors are outlined in the article. Avoidance of these pitfalls in antibiotic prescribing will improve patient care and reduce the likelihood of selecting for resistant strains in common pathogens.

Anti-Bacterial Agents↗
PubMed1993

Optimum treatment of staphylococcal infections.

Serious staphylococcal infections remain a significant clinical problem despite advances in antibacterial therapy. Resistance to penicillin is common and methicillin-resistant staphylococci have become troublesome nosocomial pathogens in many institutions. Penicillinase-resistant penicillins (e.g. flucloxacillin, cloxacillin and oxacillin) are the preferred drugs for all methicillin-susceptible staphylococcal infections, although first generation cephalosporins, beta-lactam/beta-lactamase inhibitor combinations, clindamycin, and occasionally erythromycin and cotrimoxazole (trimethoprim/sulfamethoxazole) are alternatives. Serious infections due to methicillin-resistant staphylococci should be treated with parenteral vancomycin. Teicoplanin, where available, is a suitable alternative. Rifampicin, fusidic acid and some fluoroquinolones may be useful oral alternatives, although resistance develops rapidly if they are used as single agents. Cotrimoxazole and minocycline have also proven useful when strains are susceptible. Staphylococcal toxic shock syndrome often requires aggressive resuscitation and anti-staphylococcal therapy for generally 10 to 14 days. Staphylococcus aureus bacteraemia remains a life-threatening condition which, in all but one-third of cases, is associated with an underlying septic focus such as endocarditis, osteomyelitis or occult abscess. Differentiating between complicated and uncomplicated bacteraemia is critical to define the appropriate treatment regimen. Serious staphylococcal sepsis such as endocarditis and acute osteomyelitis generally requires prolonged (4 to 6 weeks) antibiotic treatment. Coagulase-negative staphylococci are the commonest cause of prosthetic device infection, and generally require prolonged therapy with an agent to which they have proven to be sensitive, e.g. a penicillinase-resistant penicillin or vancomycin. Removal of infected foreign or prosthetic material, and drainage of deep collections remain a critical aspect of all therapy.

Anti-Bacterial Agents↗
PubMed1992

Campylobacter peritonitis in continuous ambulatory peritoneal dialysis: report of eight cases and a review of the literature.

Continuous ambulatory peritoneal dialysis (CAPD)-associated peritonitis remains the most common complication of this form of renal replacement therapy and the potential causative organisms are many and varied. Campylobacter bacteria are unusual causes of peritonitis in CAPD patients and we report our experience with eight cases and review those cases reported in the literature. In many episodes, there is a strong association with acute enterocolitis, which may precede the onset of cloudy dialysate by many days. The method of spread of these organisms from the gastrointestinal tract to the peritoneal cavity remains speculative. Bacteremic transfer would appear the most likely route, although it is probable that no single mode of spread explains all episodes. The treatment of choice of Campylobacter peritonitis is with intraperitoneal aminoglycoside in combination with oral erythromycin. An awareness of the potential for Campylobacter to cause CAPD-associated peritonitis, particularly when diarrhea is a prominent feature, has resulted in this organism becoming increasingly isolated in our unit.

Campylobacter Infections↗
PubMed1989

A national survey of antimicrobial resistance in Staphylococcus aureus in Australian teaching hospitals.

An extensive survey of the in-vitro susceptibility of clinical isolates of Staphylococcus aureus to 18 antimicrobial agents was conducted over three separate periods during 1986-1987 in 14 teaching hospitals in major Australian cities. The survey aimed to document the prevalence of resistance to a wide variety of drugs that are important as antistaphylococcal agents or as epidemiological markers. More than 7500 isolates were examined. Nationally, the prevalence of resistance was 85.3% to penicillin G, 14.4% to methicillin, 14.0% to amoxycillin/clavulanate, 9% to cephalothin, 5.4% to cephamandole, 9.9% to cefotaxime, 25.0% to erythromycin, 11.2% to clindamycin, 21.7% to tetracycline, 13.0% to gentamicin, 1.9% to amikacin, 5.8% to chloramphenicol, 18.3% to trimethoprim, 0.6% to rifampicin, 3.0% to fusidic acid and 1.2% to novobiocin. For none of the strains was resistance to vancomycin confirmed by minimal-inhibitory-concentration determination. A high proportion of the resistances was harboured in methicillin-resistant Staph. aureus, except for resistance to penicillin G, erythromycin and tetracycline. The prevalence of methicillin resistance varied widely among the states: 25.2% in Queensland, 23.5% in Victoria, 12.6% in New South Wales/the Australian Capital Territory, 11.3% in South Australia and 0.4% in Western Australia. Isolates from blood cultures were slightly-more susceptible to antimicrobial agents than were isolates from other body sites. Six common profiles of resistance to penicillin G, methicillin, erythromycin, clindamycin and tetracycline accounted for more than 95% of the isolates that were tested against all five agents. Vancomycin remains the most important antistaphylococcal drug in areas where resistance to methicillin is common.

Anti-Bacterial Agents↗
PubMed1989

Single-dose antibiotic prophylaxis in contaminated abdominal surgery.

Although perioperative antibiotic cover reduces the incidence of septic complications associated with abdominal surgery, the optimum duration of antibiotic exposure is open to question. This clinical trial compared the efficacy of a single dose of moxalactam (1 g intravenously) with an extended course of moxalactam (1 g intravenously for eight doses) in 1027 patients undergoing contaminated abdominal surgery. The wound infection rate was 5.4% (28/519) for the single-dose schedule and 6.1% (31/508) for the extended-cover regimen (the respective 95% confidence intervals being 3.6% to 7.7% and 4.2% to 8.6%). Over 80% of all patients undergoing abdominal surgery during the period of study were entered into the trial. There was no significant difference in the incidence of other complications between the two groups under study. It is concluded that a single dose of moxalactam is as effective as a 48-hour course when attempting to prevent infection after contaminated abdominal surgery.

Biliary Tract Surgical Procedures↗
PubMed1988

In vivo postantibiotic effect in a thigh infection in neutropenic mice.

The postantibiotic effect (PAE) is the suppression of bacterial growth that persists after limited exposure of organisms to antimicrobial agents. We demonstrated and standardized the in vivo PAE in a thigh infection model in neutropenic mice. Inhibitors of protein and nucleic acid synthesis induced PAEs of 1.4-7.5 h against aerobic gram-negative bacilli, whereas beta-lactam antibiotics did not induce significant PAEs. Against aerobic gram-positive cocci, cell wall-active agents and inhibitors of protein and nucleic acid synthesis induced PAEs of 1.2-7.1 h, except for penicillins, which did not induce PAEs against streptococci. With few exceptions the in vivo PAE correlated well with the PAE reported in prior in vitro studies. Residual drug in thigh tissue did not cause the PAE. Theoretically, the presence of a PAE may allow antimicrobial agents to be given more intermittently without organism regrowth after drug levels fall below the minimal inhibitory concentration.

Agranulocytosis↗
PubMed1988

Correlation of antimicrobial pharmacokinetic parameters with therapeutic efficacy in an animal model.

Current antimicrobial dosing regimens are designed to maintain active drug levels for most of the dosing interval and are based on 40-y-old observations. With use of numerous multiple-dosing regimens in an animal model, this study is the first to successfully minimize the interdependence between pharmacokinetic parameters and thereby determine, by stepwise multivariate regression analysis, that the time that serum levels exceeded the minimum inhibitory concentration (MIC) was the most significant parameter determining efficacy for beta-lactams and erythromycin against various pathogens, whereas the log area under the curve was the major parameter for aminoglycosides. Optimal dosing intervals were no greater than the time that serum levels exceeded the MIC plus the duration of the postantibiotic effect. Careful application of these concepts should allow other investigators to use more optimally dosed regimens than those previously used in preclinical trials and to design studies to improve on current dosing regimens for humans.

Animals↗
PubMed1988

Optimal duration of cefotaxime prophylaxis in abdominal and vaginal hysterectomy.

Previous studies have demonstrated that short course perioperative antibiotic prophylaxis reduces septic morbidity after hysterectomy from up to 40% down to 10 to 15%. The residual morbidity is predominantly urinary tract infection (UTI) occurring 2 to 3 days after cessation of antibiotic. We hypothesised that surgery impairs urinary drainage for 3 to 4 days postoperatively and that prolonged prophylaxis was required to prevent all postoperative sepsis. Accordingly, 224 abdominal and 69 vaginal hysterectomy patients were randomly allocated to short course (2g cefotaxime IV at anaesthesia) or long course (2g cefotaxime at anaesthesia plus 7 doses of 1g 12-hourly) prophylaxis. UTI was effectively prevented by the long course (0.9 vs 18.4% short); both treatments effectively prevented wound and pelvic sepsis. We conclude that 4 days of postoperative antibiotic is required to prevent UTI.

Adult↗
PubMed1987

Atypical pneumonia.

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Diagnosis, Differential↗