E. coli bacteraemia and antimicrobial resistance following antimicrobial prescribing for urinary tract infection in the community

Background

Urinary tract infections are one of the most common infections in primary and secondary care, with the majority of antimicrobial therapy initiated empirically before culture results are available. In some cases, however, over 40% of the bacteria that cause UTIs are resistant to some of the antimicrobials used, yet we do not know how the patient outcome is affected in terms of relapse, treatment failure, progression to more serious illness (bacteraemia) requiring hospitalization, and ultimately death. This study analyzed the current patterns of antimicrobial use for UTI in the community in Scotland, and factors for poor outcomes.

Objectives

To explore antimicrobial use for UTI in the community in Scotland, and the relationship with patient characteristics and antimicrobial resistance in E. coli bloodstream infections and subsequent mortality.

Methods

We included all adult patients in Scotland with a positive blood culture with E. coli growth, receiving at least one UTI-related antimicrobial (amoxicillin, amoxicillin/clavulanic acid, ciprofloxacin, trimethoprim, and nitrofurantoin) between 1st January 2009 and 31st December 2012. Univariate and multivariate logistic regression analysis was performed to understand the impact of age, gender, socioeconomic status, previous community antimicrobial exposure (including long-term use), prior treatment failure, and multi-morbidity, on the occurrence of E. coli bacteraemia, trimethoprim and nitrofurantoin resistance, and mortality.

Results

There were 1,093,227 patients aged 16 to 100 years old identified as receiving at least one prescription for the 5 UTI-related antimicrobials during the study period. Antimicrobial use was particularly prevalent in the female elderly population, and 10% study population was on long-term antimicrobials. The greatest predictor for trimethoprim resistance in E. coli bacteraemia was increasing age (OR 7.18, 95% CI 5.70 to 9.04 for the 65 years old and over group), followed by multi-morbidity (OR 5.42, 95% CI 4.82 to 6.09 for Charlson Index 3+). Prior antimicrobial use, along with prior treatment failure, male gender, and higher deprivation were also associated with a greater likelihood of a resistant E. coli bacteraemia. Mortality was significantly associated with both having an E. coli bloodstream infection, and those with resistant growth.

Conclusion

Increasing age, increasing co-morbidity, lower socioeconomic status, and prior community antibiotic exposure were significantly associated with a resistant E. coli bacteraemia, which leads to increased mortality.

Cost burden of Clostridioides difficile infection to the health service: A retrospective cohort study in Scotland

BACKGROUND

Clostridioides difficile infection (CDI) is associated with high healthcare demands and related costs.

AIM

To evaluate the healthcare and economic burden of CDI in hospitalized patients with community- (HOCA-CDI) or hospital-associated CDI (HOHA-CDI) in the National Health Service in Scotland.

METHODS

A retrospective cohort study was conducted, examining data between August 2010 and July 2013 from four patient-level Scottish datasets, linked to death data. Data examined included prior antimicrobial prescriptions in the community, hospitalizations, length of stay and mortality. Each CDI case was matched to three hospital-based controls on the basis of age, gender, hospital and date of admission. Descriptive economic evaluations were based on bed-day costs for different types of wards.

FINDINGS

Overall, 3304 CDI cases were included in the study. CDI was associated with additional median lengths of stay of 7.2 days for HOCA-CDI and 12.0 days for HOHA-CDI compared with their respective, matched controls. The 30-day mortality rate was 6.8% for HOCA-CDI and 12.4% for HOHA-CDI. Overall, recurrence within 90 days of the first CDI episode occurred in 373/2740 (13.6%) survivors. The median additional expenditure for each initial CDI case compared with matched controls was £1713. In the 6 months after the index hospitalization, the cost associated with a CDI case was £5126 higher than for controls.

CONCLUSION

Using routinely collected national data, we demonstrated the substantial burden of CDI on healthcare services, including lengthy hospital stays and readmissions, which increased the costs of managing patients with CDI compared with matched controls.

A retrospective cohort study into acquisition of MRSA and associated risk factors after implementation of universal screening in Scottish hospitals

OBJECTIVE

To estimate the proportion of patients who acquire methicillin-resistant Staphylococcus aureus (MRSA) while in hospital and to identify risk factors associated with acquisition of MRSA.

DESIGN

Retrospective cohort study.

PATIENTS

Adult patients discharged from 36 general specialty wards of 2 Scottish hospitals that had implemented universal screening for MRSA on admission.

METHODS

Patients were screened for MRSA on discharge from hospital by using multisite body swabs that were tested by culture. Discharge screening results were linked to admission screening results. Genotyping was undertaken to identify newly acquired MRSA in MRSA-positive patients on admission.

RESULTS

Of the 5,155 patients screened for MRSA on discharge, 2.9% (95% confidence interval [CI], 2.43-3.34) were found to be positive. In the subcohort screened on both admission and discharge (n = 2,724), 1.3% of all patients acquired MRSA while in hospital (incidence rate, 2.1/1,000 hospital bed-days in this cohort [95% CI, 1.5-2.9]), while 1.3% remained MRSA positive throughout hospital stay. Three risk factors for acquisition of MRSA were identified: age above 64 years, self-reported renal failure, and self-reported presence of open wounds. On a population level, the prevalence of MRSA colonization did not differ between admission and discharge.

CONCLUSIONS

Cross-transmission of MRSA takes place in Scottish hospitals that have implemented universal screening for MRSA. This study reinforces the importance of infection prevention and control measures to prevent MRSA cross-transmission in hospitals; universal screening for MRSA on admission will in itself not be sufficient to reduce the number of MRSA colonizations and subsequent MRSA infections.

Telephone call contact for post-discharge surveillance of surgical site infections. A pilot, methodological study

Accurate determination of superficial surgical-site infection (SSI) requires post-discharge surveillance (PDS) for up to 30 days. To be useful for regional or national audit the method must be effective, inexpensive, and acceptable to patients. We assessed the role of telephone calls to patients in PDS of SSI in 3150 patients in 32 Scottish hospitals undergoing groin hernia repair during one year. Overall, 104 (3.3%) patients opted out of the audit by declining to give a contact telephone number, 96 (3.0%) could not provide a personal telephone contact number, and 12 could not be contacted, a compliance rate of 93.3%. Two thousand, nine hundred and thirty-eight patients were contacted at one or all of the call points, i.e. 10, 20, or 30 days postoperatively, from a single call centre by medical records clerks, working to a piloted protocol. Contact data, including contact at all three time points are available on 2665 (84.6%) patients. All patients who believed their wound to be infected were seen by a healthcare worker (HCW) to confirm or refute the diagnosis. Of the 2665 patients in whom complete data are available, 140 (5.3%) patients developed confirmed wound infection and a further 57 (2.1%) thought their wound was infected, but this was not confirmed by the HCW. Patients appeared to welcome the concept of telephone contact. Methods for identifying all patients eligible for surveillance need to be improved. However, we believe this method of patient contact could be appropriate for PDS in regional or national audit.

First rotavirus, now astrovirus: the evolving benefits of RT-PCR

We compared RT-PCR and a newly developed amplified EIA for the detection of human astrovirus (HAstV) in 48 stool samples taken from children of less than five years of age with gastroenteritis. The RT-PCR classified more samples as positive than the EIA (18 versus 8). Without sensitive diagnosis, infection control policies will be disadvantaged and the true economic burden of HAstV underestimated.