Enterococcal bacteraemia 'silent but deadly': a population-based cohort study.

BACKGROUND: The high mortality rate of patients with enterococcal infections has been shown to be associated with the severity of underlying comorbidities. AIMS: To characterise the epidemiology, clinical characteristics, outcomes and predictors of mortality in patients with enterococcal bacteraemia. METHODS: This was a retrospective cohort study of all enterococcal bacteraemia episodes in the Barwon region between January 2010 and March 2017. We assessed the epidemiology, clinical characteristics, outcomes and predictors of mortality using descriptive statistics and simple and multiple logistic regression analyses. RESULTS: The incidence of enterococcal bacteraemia was 19.9/100 000 person-years. Males comprised 68.4%, and the median age was 71 years. Common comorbidities were gastrointestinal tract disease, urological disease, malignancies and cardiovascular disease. Infective endocarditis was observed in 15% of patients, and 1 of 27 also had colorectal cancer. Twelve patients referred for colonoscopy demonstrated previously undiagnosed colorectal neoplasia in 75% of these cases. The 30-day and 1-year mortality rates were 11.7 and 40.2% respectively. Sixty-nine cases with vancomycin-resistant Enterococcus were observed. Multiple logistic regression suggested that the presence of underlying urological malignancy (adjusted odds ratio = 3.57, 95% confidence intervals = 1.10-11.65, P = 0.035) and colorectal cancer (adjusted odds ratio = 4.47, 95% confidence intervals = 1.36-14.66, P = 0.014) were significant predictors of 1-year mortality. CONCLUSIONS: Microbiological cure was inversely associated with 30-day mortality. The presence of underlying urological and colorectal malignancy was a predictor of 1-year mortality. We identified the importance of evaluating patients with Enterococcus faecalis bacteraemia for underlying colorectal neoplasia. Routine colonoscopy is recommended in patients with E. faecalis bacteraemia or infective endocarditis with an unclear source of infection.

Vaccination with chemically attenuated Plasmodium falciparum asexual blood-stage parasites induces parasite-specific cellular immune responses in malaria-naïve volunteers: a pilot study.

BACKGROUND: The continuing morbidity and mortality associated with infection with malaria parasites highlights the urgent need for a vaccine. The efficacy of sub-unit vaccines tested in clinical trials in malaria-endemic areas has thus far been disappointing, sparking renewed interest in the whole parasite vaccine approach. We previously showed that a chemically attenuated whole parasite asexual blood-stage vaccine induced CD4+ T cell-dependent protection against challenge with homologous and heterologous parasites in rodent models of malaria. METHODS: In this current study, we evaluated the immunogenicity and safety of chemically attenuated asexual blood-stage Plasmodium falciparum (Pf) parasites in eight malaria-naïve human volunteers. Study participants received a single dose of 3 × 107 Pf pRBC that had been treated in vitro with the cyclopropylpyrolloindole analogue, tafuramycin-A. RESULTS: We demonstrate that Pf asexual blood-stage parasites that are completely attenuated are immunogenic, safe and well tolerated in malaria-naïve volunteers. Following vaccination with a single dose, species and strain transcending Plasmodium-specific T cell responses were induced in recipients. This included induction of Plasmodium-specific lymphoproliferative responses, T cells secreting the parasiticidal cytokines, IFN-γ and TNF, and CD3+CD45RO+ memory T cells. Pf-specific IgG was not detected. CONCLUSIONS: This is the first clinical study evaluating a whole parasite blood-stage malaria vaccine. Following administration of a single dose of completely attenuated Pf asexual blood-stage parasites, Plasmodium-specific T cell responses were induced while Pf-specific antibodies were not detected. These results support further evaluation of this chemically attenuated vaccine in humans. TRIAL REGISTRATION: Trial registration: ACTRN12614000228684 . Registered 4 March 2014.

Capnocytophaga canimorsus Sepsis Following a Minor Dog Bite to the Finger: Case Report.

Capnocytophaga canimorsus is a gram-negative bacillus present in the oral cavities of 22% to 74% of healthy dogs. Capnocytophaga canimorsus has unique virulence factors that enable it to evade the human immune system and cause life-threatening sepsis following a dog bite. We report a previously well 68-year-old woman who presented with septic shock and multiorgan failure following a seemingly minor dog bite to the finger. The patient required intensive care treatment, intravenous antibiotic therapy, and multiple surgical procedures including amputation of the affected finger. The septicemia and coagulopathy that ensued resulted in gangrene and amputation of additional fingers and toes. The purpose of this report is to raise awareness of this organism among hand surgeons when faced with a patient presenting in septic shock and minimal signs at the site of a dog bite.

Staphylococcus aureus Is the Predominant Pathogen in Hospitalised Patients with Diabetes-Related Foot Infections: An Australian Perspective.

Diabetes prevalence continues to increase worldwide, which has led to a rising incidence of diabetes-related foot infections (DFIs). There is significant local variation in the microbiology of DFIs, and Pseudomonas spp. is suggested to be more prevalent in subtropical climates. The aim of this study was to investigate the local microbiological findings in patients admitted to the hospital with DFIs. This retrospective study analysed data from all adult patients diagnosed with diabetes and admitted to the hospital for the treatment of a DFI between 1 January 2021 and 31 December 2022. Both superficial wound swabs and tissue cultures were included. The Infectious Diseases Society of America classification system was used to categorise the severity of the DFI. Patient characteristics and demographics were analysed using descriptive statistics. One hundred fifty-one episodes of care were included. Most of the DFIs were classified as moderate infections 101/151 (67%). The most commonly isolated microorganism was Staphylococcus aureus (33%) followed by normal skin flora (11%) and ß-haemolytic streptococci (7%). P. aeruginosa was isolated more commonly in those with chronic DFIs (10%) compared to those with acute DFIs (2%). Despite the frequent identification of S. aureus, 83% of patients received an antipseudomonal antibiotic. The introduction of multidisciplinary DFI rounds should be considered.

Epidemiology and clinical outcomes of hepatitis delta (D) virus infection in Queensland, Australia.

OBJECTIVES: To investigate the epidemiology, clinical characteristics and outcomes of those with hepatitis delta virus (HDV) infection in Queensland, Australia. DESIGN: Retrospective cohort study of individuals tested for HDV between 1997 and 2016 in the public healthcare system in Queensland. RESULTS: 179 individuals recorded positive HDV serology between 1997 and 2016, with a total of 4407 individuals undergoing testing (seroprevalence 4.1%). The majority of HDV positive individuals were male and were born overseas. Those born in Africa had a higher risk ratio (RR) for HDV infection (RR, 1.55; 95% CI, 1.14-2.09); being born in Asia was associated with a relatively lower risk of HDV infection (RR, 0.36; 95% CI, 0.27-0.58). Positive hepatitis C virus (HCV) serology was significantly associated with positive HDV serology (RR, 2.98; 95% CI, 2.36-3.78). Of the HDV positive individuals born in Australia, the majority were HCV positive (69.8%). HDV positive individuals were less likely to be Hepatitis B e antigen (HBeAg) positive (RR, 0.64; 95% CI, 0.45-0.93) and recorded lower hepatitis B virus (HBV) viral loads. Positive HDV serology was associated with increased risk of liver cirrhosis (RR, 2.3; 95% CI 1.73-3.07) and liver transplantation (RR, 1.93; CI 1.31-2.85). Only 8% of HDV positive individuals underwent HDV treatment. CONCLUSIONS: In Queensland, HDV seropositivity is associated with overseas birth, particularly in Africa. HDV infection is associated with decreased HBV viraemia and more advanced liver disease.