Clinical manifestations of invasive meningococcal disease in Victoria with the emergence of serogroup W and serogroup Y Neisseria meningitidis

BACKGROUND

Historically, Australian cases of invasive meningococcal disease (IMD) have been most frequently caused by Neisseria meningitidis serogroup B, but recently an increase in cases due to serogroup W (MenW) and serogroup Y (MenY) has occurred.

AIM

To determine whether clinical manifestations of IMD have changed due to increased incidence of MenW and MenY.

METHODS

We performed a retrospective review of IMD cases notified to the Department of Health and Human Services in Victoria, Australia. We compared the period between January 2013 and June 2015 (defined as P1) immediately before the increase in MenW and MenY was noted, with the equal time period of July 2015 to December 2017 (P2), when this increase was observed.

RESULTS

IMD was notified more frequently in P2 than P1 (1.24 vs 0.53 per 100 000 person-years, P < 0.001). IMD cases in P2 were older (46 vs 19 years, P < 0.001), and more likely due to MenW (92/187, 49.2% vs 11/80, 13.8%, P < 0.001) or MenY (31/187, 16.6% vs 4/80, 5.0%, P = 0.01). IMD cases from P2 were more likely bacteraemic (151/187, 80.7% vs 55/80, 68.8%, P = 0.04), while meningitis (68/187, 36.4% vs 41/80, 51.3%, P = 0.03) and rash (65/181, 35.9% vs 45/78, 57.7%, P = 0.002) were less frequent. Intensive care unit admission rates and in-hospital mortality were unchanged.

CONCLUSION

Alongside an increase in IMD in Victoria, the proliferation of cases of MenW and MenY occurred in older patients, and were more often identified through bacteraemia rather than meningitis or purpura fulminans. Clinicians should be aware of these changes to facilitate earlier identification and treatment of IMD.

Potential interventions for an antimicrobial stewardship bundle for Escherichia coli bacteraemia

INTRODUCTION

Escherichia coli is the most commonly identified bacteraemia, and causes a broad spectrum of diseases. The range of clinical conditions associated with E. coli bacteraemia mean that antimicrobial therapy is highly variable. This study aimed to determine the workload, efficiency and potential impact of an antimicrobial stewardship (AMS) bundle approach to E. coli bacteraemia.

METHODS

An observational cohort study of patients with E. coli bacteraemia was performed, and a review of each case's entire medical record was undertaken. A number of AMS interventions were modelled on this cohort to assess their impact on overall days of antimicrobial therapy and time to optimized antimicrobial therapy.

RESULTS

In total, 566 episodes of E. coli bacteraemia were identified. A number of AMS interventions were modelled to assess their impact. The strict implementation of guideline-based therapy was found to increase the number of patients receiving ineffective empirical therapy to 38/266 (14.3%) compared with 27/266 (10.2%) patients when w hen non-guideline-adherent therapy was allowed. A scheduled review by an AMS team on day 3 of empirical therapy could lead to a narrower-spectrum intravenous antibiotic in 237/515 (46%) cases, and 386 cases (68.2% of cohort) could have their duration of therapy reduced by a median of 7 days.

CONCLUSION

This study provides detailed description of a large cohort of patients with E. coli bacteraemia. There remains significant variability in empirical treatment, choice of step-down therapy and antimicrobial duration. A significant opportunity exists for AMS programmes to impact the management of E. coli bacteraemia through a bundled approach.

COVID-MATCH65-A prospectively derived clinical decision rule for severe acute respiratory syndrome coronavirus 2

OBJECTIVES

We report on the key clinical predictors of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection and present a clinical decision rule that can risk stratify patients for COVID-19.

DESIGN, PARTICIPANTS AND SETTING

A prospective cohort of patients assessed for COVID-19 at a screening clinic in Melbourne, Australia. The primary outcome was a positive COVID-19 test from nasopharyngeal swab. A backwards stepwise logistic regression was used to derive a model of clinical variables predictive of a positive COVID-19 test. Internal validation of the final model was performed using bootstrapped samples and the model scoring derived from the coefficients, with modelling performed for increasing prevalence.

RESULTS

Of 4226 patients with suspected COVID-19 who were assessed, 2976 patients underwent SARS-CoV-2 testing (n = 108 SARS-CoV-2 positive) and were used to determine factors associated with a positive COVID-19 test. The 7 features associated with a positive COVID-19 test on multivariable analysis were: COVID-19 patient exposure or international travel, Myalgia/malaise, Anosmia or ageusia, Temperature, Coryza/sore throat, Hypoxia-oxygen saturation < 97%, 65 years or older-summarized in the mnemonic COVID-MATCH65. Internal validation showed an AUC of 0.836. A cut-off of ≥ 1.5 points was associated with a 92.6% sensitivity and 99.5% negative predictive value (NPV) for COVID-19.

CONCLUSIONS

From the largest prospective outpatient cohort of suspected COVID-19 we define the clinical factors predictive of a positive SARS-CoV-2 test. The subsequent clinical decision rule, COVID-MATCH65, has a high sensitivity and NPV for SARS-CoV-2 and can be employed in the pandemic, adjusted for disease prevalence, to aid COVID-19 risk-assessment and vital testing resource allocation.

Twice daily cefazolin is effective for treatment of serious methicillin-sensitive Staphylococcus aureus infection in an outpatient parenteral antimicrobial therapy program

Background:

The use of cefazolin for infections caused by Staphylococcus aureus has been demonstrated to be effective, and associated with fewer adverse effects compared with anti-staphylocccal penicillins; however, use of cefazolin on outpatient parenteral antimicrobial therapy (OPAT) programs often requires the use of continuous infusions. We report the outcomes of patients with serious infections caused by methicillin-sensitive S. aureus (MSSA) treated using twice daily cefazolin by a large tertiary hospital OPAT program. The aim of this study was to evaluate the safety, efficacy and outcomes after 90 days of follow up for patients with serious infections caused by MSSA treated with twice daily cefazolin by our OPAT program.

Methods:

A retrospective analysis of clinical outcomes of cases treated for a serious infection proven to be caused by MSSA treated with cefazolin monotherapy on the OPAT program at a tertiary hospital between January 2010 and July 2016 (6.5 years). Outcome measures included readmission rate, adverse drug reactions and clinical cure.

Results:

A total of 111 cases of serious MSSA infection were treated with cefazolin in the OPAT service during the study period, including 52 with peripheral or vertebral osteomyelitis and 13 with infective endocarditis; 56 patients had bacteraemia. Median duration of intravenous antibiotic therapy was 41 days, and the median proportion of intravenous therapy administered via OPAT was 69%. Two patients had recurrence of infection within 90 days, but were in the setting of retained prosthetic material. A total of 4% of patients experienced an adverse drug reaction. No cases of antibiotic failure were identified.

Conclusions:

The use of twice daily cefazolin for serious MSSA infection on an OPAT program is safe and effective. Further study is needed to assess for noninferiority to conventional treatment regimes.