An outbreak of multi-drug resistant Escherichia coli urinary tract infection in an elderly population: a case-control study of risk factors.

BACKGROUND: Prevention of infection due to multi-drug resistant organisms is particularly challenging because of the spread of resistant bacteria beyond hospitals into the community, including nursing homes. This study aimed to identify risk factors for the acquisition of a multidrug resistant (MDR) Escherichia coli in a local outbreak. METHODS: Study participants were all aged over 65 years. Cases had the MDR E. coli isolated from a routine urine sample, and controls had a urine sample submitted to the laboratory in the same time period but the MDR E. coli was not isolated. Information from clinical records was used to identify risk factors both in the hospital and the community setting for acquisition of the MDR E. coli. RESULTS: 76 cases and 156 controls were identified and included in the study. In a multivariate analysis, risk factors statistically significantly associated with acquisition of the MDR E. coli were female gender (adjusted OR 3.2; 95 % confidence interval 1.5-6.9), level of care (high dependency OR 7.5; 2.2-25.7) compared with living independently), and in hospital prescription of antimicrobials to which the MDR E. coli was resistant (OR 5.6; 2.5-12.9). CONCLUSIONS: The major risk factors for the acquisition of a MDR E. coli were found to be residence in a nursing home and in-hospital prescription of antimicrobials to which the MDR E. coli was resistant. This emphasises that prevention of transmission of MDROs within a community needs to involve both hospitals and also other healthcare organizations, in this case nursing homes.

Antibiotic treatment of women with uncomplicated cystitis before and after allowing pharmacist-supply of trimethoprim.

Background In 2012, New Zealand reclassified trimethoprim to allow specially trained pharmacists to supply it without a prescription to women with symptoms suggesting uncomplicated cystitis, under strict criteria for supply. Objective To assess how this policy change allowing pharmacist supply of trimethoprim affected overall antibiotic supply. Setting Randomly selected community pharmacies throughout New Zealand. Methods Data were collected in pharmacies before the implementation ('baseline') and 1 year later ('post-implementation'). Pharmacy staff recorded prescription and nonprescription supplies for treatment or prevention of suspected urinary tract infections. Women with a prescription for treatment or prevention of presumed urinary tract infection or purchasing a non-prescription medicine for this purpose were invited to self-complete a questionnaire. National prescribing data were extracted for trimethoprim, nitrofurantoin and norfloxacin. Main outcome measure Antibiotic use in women with UTIs from dispensed prescriptions (baseline and post-implementation) and pharmacist-supplied trimethoprim (post-implementation), particularly focusing on women aged 16-65 years with an antibiotic for presumed cystitis without complicating features. Results Baseline data were provided by 139 pharmacies, 120 of which provided post-implementation data. In women with presumed cystitis without complicating features, prescriptions before and after the implementation were primarily for trimethoprim. Overall antibiotic use, and use of second-line agents did not increase post-implementation. Pharmacist-supplies of trimethoprim were modest nearly 1 year after the service started. Conclusion Supply of trimethoprim by specially trained pharmacists working within strict criteria for supply appeared to have little overall effect on antibiotic use. Further research on patient outcomes, resistance and changes over time is recommended.

Treatment of uncomplicated cystitis: analysis of prescribing in New Zealand.

AIMS: To describe prescribing for women with suspected urinary tract infections, including suspected uncomplicated cystitis, in New Zealand. METHODS: Randomly selected community pharmacies participated in the study. Women attending the pharmacy in a 2-week period in 2012 for prescribed or non-prescription treatment of symptoms suggesting a urinary tract infection, or prophylaxis of a urinary tract infection, were invited to self-complete a questionnaire. Analysis focused on prescribing for women with symptoms of cystitis without complicating features. RESULTS: Valid questionnaires arising from a prescription treatment were received from 789 patients from 139 pharmacies. Questionnaire data indicated that 17% of women had symptoms of cystitis without complicating features. Most prescribing was for a first-line agent, trimethoprim (59%) or nitrofurantoin (14%), but norfloxacin was also common (21%). Women with self-reported antibiotic use for suspected cystitis in the past 6 months were more likely to be prescribed norfloxacin than those with no such use. Many prescriptions were for a dose or duration outside those recommended in New Zealand guidelines. CONCLUSIONS: While use of first-line agents is generally high, norfloxacin use could be reduced further. There is scope to understand clinical practice that deviates from guideline use regarding dose and duration.

Toys are a potential source of cross-infection in general practitioners' waiting rooms.

The waiting rooms of general practitioners' surgeries usually have toys provided for children. The level of contamination of these toys and the effectiveness of toy decontamination was investigated in this study. Hard toys from general practitioners' waiting rooms had relatively low levels of contamination, with only 13.5% of toys showing any coliform counts. There were no hard toys with heavy contamination by coliforms or other bacteria. Soft toys were far more likely to be contaminated, with 20% of toys showing moderate to heavy coliform contamination and 90% showing moderate to heavy bacterial contamination. Many waiting-room toys are not cleaned routinely. Soft toys are hard to disinfect and tend to rapidly become recontaminated after cleaning. Conversely, hard toys can be cleaned and disinfected easily. Soft toys in general practitioners' waiting rooms pose an infectious risk and it is therefore recommended that soft toys are unsuitable for doctors' waiting rooms.

Antibiotic resistance in uncomplicated urinary tract infection: problems with interpreting cumulative resistance rates from local community laboratories.

AIMS: To determine the resistance rates and patterns in bacteria causing uncomplicated urinary tract infections (UTIs) presenting to general practitioners (GPs) in Christchurch. METHODS: 82 randomly selected GPs in Christchurch participated in the study. Midstream urine (MSU) samples were prospectively collected for standard microbiological analysis on all women between the ages of 16 and 50 years presenting with symptoms of dysuria and frequency and who had positive dipstick testing to either (or both) nitrites or leucocytes. MSUs were submitted for bacterial colony counts and resistance testing of isolates present in adequate numbers. RESULTS: 374 specimens were collected. 299 filled the inclusion criteria, of which 94 fulfilled criteria for significant infection. Trimethoprim resistance was found in 8, (8.5%) (95%CI 2.8,14.2) overall with a resistance rate for Escberichia coli (E. coli) to trimethoprim of 11.5%. This compared with cumulative resistance rates from local community laboratories for E. coli to trimethoprim of 19%. For a woman in this age group presenting with symptoms of UTI we estimated that her probability of having a trimethoprim resistant organism was 2.7%. CONCLUSION: Trimethoprim remains a reasonable first line treatment for uncomplicated UTI in Christchurch. Actual resistance rates are significantly less than those derived from routine pooled laboratory specimens, and when used in an intention to treat calculation to inform empiric prescribing, become even less significant. While collection of these routine data is essential to provide early warning of emergent resistance, a truly representative rate should be determined to inform prescribing decisions if resistance appears to be increasing.

Regulation of chicken contamination is urgently needed to control New Zealand's serious campylobacteriosis epidemic.

New Zealand's campylobacteriosis epidemic reached a new peak in May 2006 with the annualised national notification rate exceeding 400 per 100,000 for the first time, the highest national rate reported in the literature. The epidemic is estimated to cause at least 1 fatality a year, >800 hospitalisations, and >100,000 cases in the community, and cost the New Zealand economy 75 million dollars per annum. There is overwhelming epidemiological and laboratory evidence that fresh chicken is the dominant source of human infection. The seriousness of this epidemic justifies rapid, decisive action to reduce human exposure to this pathogen. There is good international evidence to support removal of fresh chicken from the food supply, with its reintroduction only when it can be shown to pose a very low risk to human health. Because freezing can substantially reduce Campylobacter levels, frozen chicken could be substituted to allow continued consumption of this popular food. Efforts to reduce Campylobacter colonisation of poultry flocks and contamination during chicken processing and distribution, along with continued consumer education, are important, but do not appear sufficient to control this epidemic in the short to medium term.

Increased rates of trimethoprim resistance in uncomplicated urinary tract infection: cause for concern?

AIMS: To assess changes in trimethoprim resistance over 2 years in bacteria causing uncomplicated urinary tract infections (UTIs) presenting to a representative group of general practitioners (GPs) in Christchurch. METHODS: Seventy-six randomly selected GPs in Christchurch (the Christchurch Sentinel network) participated in the study. Using the same methodology as in the previously reported 2000 collection, midstream urine (MSU) samples were prospectively collected for standard microbiological analysis on all women between the ages of 16 and 50 years presenting with symptoms of dysuria and frequency and who had positive dipstick testing for either nitrites, leucocytes, or both. MSUs were submitted for bacterial colony counts and resistance testing of isolates present in numbers >105 cfu/ml of urine. RESULTS: 216 dipstick positive specimens were collected in the survey period; 105 of these fulfilled criteria for significant bacteriuria. Trimethoprim resistance was found in 16 (15.2%) overall, with a resistance rate for Escherichia coli (E. coli) to trimethoprim of 17.7%. When compared to the proportions of organisms resistant in the 2000 study, there were apparent but non significant increases in the total resistance among pathogens (+6.7%) and E. coli resistance (+5.8%). Rates of antibiotic resistance of all organisms to nitrofurantoin (2.9%) and norfloxacin (0.95%) remain low. There was a statistically significant increase in resistance among all women presenting with symptoms and a positive dipstick test (+5.3%; 95% CI: 1.5%-9.1%). For a woman in this age group presenting with symptoms of urinary tract infection and a positive dipstick test, we estimate that her probability of having a trimethoprim-resistant organism in 2002 was 7.4% compared with 2.7% in 2000. CONCLUSION: Trimethoprim resistance of E. coli causing uncomplicated UTI appears to be rising in Christchurch. This may reflect the promotion and extensive use of this agent as first-line treatment. Whilst these data indicate that trimethoprim remains a reasonable first-line empiric treatment in this condition, this may change if trimethoprim resistance continues to rise. The apparent increase over a relatively short period (2-3 years) demonstrates the importance of regular surveillance. A third study is required to confirm whether this is a significant trend.

Molecular characterization of penicillin non-susceptible Streptococcus pneumoniae in Christchurch, New Zealand.

OBJECTIVES: To determine the epidemiological relationship between non-invasive penicillin non-susceptible Streptococcus pneumoniae isolates collected in the Christchurch community between 1997 and 2001. METHODS: One hundred and ninety-seven pneumococcal isolates were examined by macrorestriction profile analysis of SmaI-digested genomic DNA separated by PFGE and restriction fragment length polymorphism analysis of penicillin binding protein genes. RESULTS: Four major clonal lineages were identified, the largest and most homogeneous containing 95 (48.2%) of the isolates, the bulk of which (93.7%), had identical macrorestriction patterns. Members of this clonal group were multidrug-resistant and exhibited high resistance to third-generation cephalosporins, with MICs > or =8.0 mg/L not uncommon (23.1%). Two of the clonal groups, each containing 24 (12.2%) isolates, appeared indistinguishable from the globally widespread Spain23F-1 and France9V-3 strains, respectively. The fourth (12.7% of isolates) multidrug-resistant clone possessed intermediate penicillin susceptibility (MIC 0.12 mg/L). CONCLUSIONS: This study shows that several distinct penicillin-resistant pneumococcal clones are present in the Christchurch community, most of which appear to have been imported into New Zealand.

Evidence for a general-purpose genotype in Candida albicans, highly prevalent in multiple geographical regions, patient types and types of infection.

Epidemiological studies, using the probe Ca3, have shown that in a given patient population a single cluster of genetically related Candida albicans isolates usually predominates. The authors have investigated whether these local clusters are part of a single group, geographically widespread and highly prevalent as an aetiological agent of various types of candidiasis. An unrooted neighbour-joining tree of 266 infection-causing C. albicans isolates (each from a different individual) from 12 geographical regions in 6 countries was created, based on genetic distances generated by Ca3 fingerprinting. Thirty-seven per cent of all isolates formed a single genetically homogeneous cluster (cluster A). The remainder of isolates were genetically diverse. Using the maximum branch length within cluster A as a cut-off, they could be divided into 37 groups, whose prevalence ranged between 0.3% and 9%. Strains from cluster A were highly prevalent in all but one geographical region, with a mean prevalence across all regions of 41%. When isolates were separated into groups based on patient characteristics or type of infection, strains from cluster A had a prevalence exceeding 27% in each group, and their mean prevalence was 43% across all patient characteristics. These data provide evidence that cluster A constitutes a general-purpose genotype, which is geographically widespread and acts as a predominant aetiological agent of all forms of candidiasis in all categories of patients surveyed.