People who inject drugs are at risk of acute bacterial and fungal injecting-related infections. There is evidence that incidence of hospitalizations for injecting-related infections are increasing in several countries, but little is known at an individual level. We aimed to examine injecting-related infections in a linked longitudinal cohort of people who inject drugs in Melbourne, Australia. A retrospective descriptive analysis was conducted to estimate the prevalence and incidence of injecting-related infections using administrative emergency department and hospital separation datasets linked to the SuperMIX cohort, from 2008 to 2018. Over the study period, 33% (95%CI: 31–36%) of participants presented to emergency department with any injecting-related infections and 27% (95%CI: 25–30%) were admitted to hospital. Of 1,044 emergency department presentations and 740 hospital separations, skin and soft tissue infections were most common, 88% and 76%, respectively. From 2008 to 2018, there was a substantial increase in emergency department presentations and hospital separations with any injecting-related infections, 48 to 135 per 1,000 person-years, and 18 to 102 per 1,000 person-years, respectively. The results emphasize that injecting-related infections are increasing, and that new models of care are needed to help prevent and facilitate early detection of superficial infection to avoid potentially life-threatening severe infections.

The association between time to positivity (TTP) of blood culture and the clinical prognosis of patients with Klebsiella pneumoniae bloodstream infection (BSI) remains unclear. A retrospective study of 148 inpatients with BSI caused by K. pneumoniae was performed at Shanghai Tongji Hospital, China, from October 2016–2020. The total in-hospital fatality rate was 32%. The median TTP was 11.0 (7.7–16.1) h and the optimal cutoff for prediction of in-hospital mortality was 9.4 h according to the ROC curve. Early TTP (<9.4 h) was a risk factor for in-hospital mortality by univariate analysis (OR = 2.5, 95% CI 1.2–5.0, P = 0.01), but not by multivariate analysis (OR = 2.7, 95% CI 1.0–7.4, P = 0.06). Old age, serum creatinine, white blood cells, and C-reactive protein values were risk factors for in-hospital mortality by multivariate analysis. Early TTP was not a risk factor for septic shock (OR = 1.8, 95% CI 0.6–5.1, P = 0.27) or ICU admission (OR = 1.0, 95% CI 1.0–1.0, P = 0.32). In conclusion, the in-hospital fatality rate of patients with K. pneumoniae BSI was relatively high and associated with an early TTP of blood cultures. However, no increased risk of mortality, septic shock or ICU admission was evident in early TTP patients.

Our population-based study objectives were to describe characteristics and outcomes of Escherichia coli bloodstream infections (BSIs), and to evaluate factors associated with outcomes. We included incident E. coli BSIs from western interior residents (British Columbia, Canada; 04/2010–03/2020). We obtained data including patient demographics, location of onset, infection focus, Charlson comorbidity index (CCI), antimicrobial resistance, 30-day all-cause mortality and length of hospital stay (LOS). Using multivariable logistic regression models fitted with generalised estimating equations, we estimated factors associated with 30-day mortality and long post-infection LOS (>75th percentile). We identified 1080 incident E. coli BSIs in 1009 patients. The crude incidence and 30-day mortality rates were 59.1 BSIs and 6.8 deaths/100 000 person-years, respectively. The 30-day case fatality risk was 11.5%. Compared to community-acquired E. coli BSIs, either healthcare-associated or nosocomial cases had higher odds of 30-day mortality. Older cases, non-urogenital BSI foci and CCI ⩾ 3 had higher odds of 30-day mortality compared to younger cases, urogenital foci and CCI < 3. In patients that survived to discharge, those with extended-spectrum β-lactamase (ESBL)-producing E. coli BSIs, nosocomial BSIs, and CCI ⩾ 3 had higher odds of long post-infection LOS compared to those with non-ESBL-producing, community-acquired and healthcare-associated, and CCI < 3. There is a substantial disease burden from E. coli BSIs.

Although patients with end-stage renal disease (ESRD) are known to be at high risk for developing bloodstream infections (BSI), the risk associated with lesser degrees of renal dysfunction is not well defined. We sought to determine the risk for acquiring and dying from community-onset BSIs among patients with renal dysfunction. A retrospective, population-based cohort study was conducted among adult residents without ESRD in the western interior of British Columbia. Estimated glomerular filtration rates (eGFR) were determined for cases and incidence rate ratios (IRR) were calculated using prevalence estimates. Overall, 1553 episodes of community-onset BSI were included of which 39%, 32%, 17%, 9%, 2% and 1% had preceding eGFRs of ≥90, 60–89, 45–59, 30–44, 15–29 and <15 ml/min/m2, respectively. As compared to those with eGFR ≥60 ml/min/m2, patients with eGFR 30–59 ml/min/m2 (IRR 4.4; 95% confidence interval (CI) 3.9–4.9) and eGFR <30 ml/min/m2 (IRR 7.0; 95% CI 5.0–9.5) were at significantly increased risk for the development of community-onset BSI. An eGFR <30 ml/min/m2 was an independent risk factor for death (odds ratio 2.3; 95% CI 1.01–5.15). Patients with renal dysfunction are at increased risk for developing and dying from community-onset BSI that is related to the degree of dysfunction.

Bloodstream infection (BSI), caused by Klebsiella pneumoniae, is associated with high morbidity and mortality, where the pks gene cluster plays a major role in their occurrence and prevalence. Information on the prevalence and characteristics of this gene cluster in K. pneumoniae is currently limited in mainland China. We therefore undertook a multicentre longitudinal study which revealed the prevalence, overall, community-onset and hospital-acquired BSI to be 20.5%, 28.3% and 13.0%, respectively. Compared to pks-negative, pks-positive isolates were significantly more susceptible to antimicrobial agents with a low incidence (5.1%) of multidrug-resistance and with infrequent extended-spectrum beta-lactamase (ESBL) production. Among pks-positive isolates, ST23 (78/117) and ST65 (20/117) were the dominant sequence types, and the majority harboured virulence genes. Community-onset BSI patients infected with pks-positive isolates had a higher proportion of liver abscesses and a lower proportion of biliary obstructions (P < 0.05). The pks-positive isolates were mostly sporadic in the phylogenetic tree, with a 65.8 and 47.0 average allele difference between Clade 1 and Clade 2, respectively. We concluded that although pks-positive K. pneumoniae were generally susceptible to antimicrobials, the high prevalence of such isolates in community cases and the genotoxicity, merits further investigation.

Bloodstream infection (BSI) is a serious complication in immunocompromised hosts. This study compares epidemiological, clinical and microbiological characteristics of BSI among children with haematological malignancies (HM) and solid tumours (ST). The study was conducted from October 2012 through to November 2015 at a referral hospital for cancer care and included the first BSI episode detected in 210 patients aged 18 years or less. BSI cases were prospectively detected by daily laboratory-based surveillance. The Centers for Disease Control and Prevention definitions for primary or secondary BSI were used. A higher proportion of use of corticosteroids (P = 0.02), chemotherapy (P = 0.01) and antibiotics (P = 0.05) before the BSI diagnosis; as well as of neutropenia (P < 0.001) and mucositis (P < 0.001) at the time of BSI diagnosis was observed in patients with HM than with ST. Previous surgical procedures (P = 0.03), mechanical ventilation (P = 0.01) and bed confinement (P < 0.001) were more frequent among children with ST. The frequency of use of temporary (P = 0.01) and implanted vascular lines (P < 0.01) was significantly higher in children with ST than with HM while the tunnelled line (P = 0.01) use was more frequent in children with HM as compared to ST. Most (n = 181) BSI cases were primary BSI. BSI associated with a tunnelled catheter was more frequent in children with HM (P < 0.01), whereas BSI associated with an implanted (P < 0.01) or temporary central line (P < 0.02) was more common in patients with ST. BSI associated with mucosal barrier injury was more frequent (P = 0.01) in children with HM. Indication for intensive care was more frequent in children (P = 0.05) with ST. Mortality ratio was similar in children with ST and HM, and length of hospital stay after BSI was higher in patients with HM than with ST (median of 19 vs. 13 days; P = 0.02). Infection caused by Gram-negative bacteria (P = 0.04) and polymicrobial infections (P = 0.05) due to Gram-positive cocci plus fungus was more common in patients with HM. These findings suggest that the characteristics of BSI acquisition and mortality can be cancer-specific.

We investigated the virulence gene carriage and molecular type characteristics of Staphylococcus aureus isolates from bloodstream infections (BSIs) and skin and soft tissue infections (SSTIs) in children. A total of 71 isolates, 16 of which were methicillin-resistant S. aureus (MRSA), were investigated by PCR for virulence-associated gene profiles, sequence type and spa type. This revealed that 76·7% and 53·7% of the SSTI and BSI isolates, respectively, exhibited simultaneous carriage of ⩾10 virulence genes. Compared to BSI isolates, carriage rates for hla, hlb, cna, clfA, seb, sec and pvl genes were significantly higher in SSTI isolates. By contrast, carriage of eta, etb and sea was significantly higher for BSI isolates. Thirty-four sequence types (STs) and 36 spa types were identified in the 71 isolates and included 14 novel STs and four novel spa types. ST59-MRSA-IV/V-t437 was the most common clone in the MRSA isolates. We concluded that virulence determinants are widely distributed in isolates of S. aureus strains from children with BSIs and SSTIs, with an unexpectedly high rate in SSTI isolates. Future profiling of S. aureus virulence determinants may allow the prediction of severity and outcome for children with these infections.

An open-label, prospective cohort, active healthcare-associated infection surveillance sequential study was conducted in four Italian intensive-care units. The aim was to determine the effect of switching from open (glass) to closed fully collapsible plastic intravenous (i.v.) infusion containers (Viaflo®) on rate and time to onset of central venous catheter-associated bloodstream infections (CVC-BSI). A total of 1173 adult patients were enrolled. The CVC-BSI rate during the open container period was significantly higher than during the closed container period (8·2 vs. 3·5 BSI/1000 CVC days, relative risk 0·43, 95% confidence interval 0·22–0·84, P=0·01). The probability of developing a CVC-BSI was assessed over time comparing open and closed i.v. infusion containers. In the closed container period, it remained fairly constant (0·8% at days 1–3 to 1·4% at days 7–9) whereas during the open container period it increased (2% at days 1–3 to 5·8% at days 7–9). Overall, the chance of acquiring a CVC-BSI significantly decreased by 61% in the closed container period (Cox proportional hazard ratio 0·39, P=0·004).

To determine the incidence, risk factors for, and the influence of bloodstream infections (BSIs) on mortality of patients in intensive-care units (ICUs), prospectively collected data from all patients with a stay in an ICU >48 h, during a 1-year period, were analysed. Of 572 patients, 148 developed a total of 232 BSI episodes (incidence 16·3 episodes/1000 patient-days). Gram-negative organisms with high level of resistance to antibiotics were the most frequently isolated pathogens (157 strains, 67·8%). The severity of illness on admission, as estimated by APACHE II score (OR 1·07, 95% CI 1·04–1·1, P<0·001), the presence of acute respiratory distress syndrome (OR 3·57, 95% CI 1·92–6·64, P<0·001), and a history of diabetes mellitus (OR 2·37, 95% CI 1·36–4·11, P=0·002) were risk factors for the occurrence of BSI whereas the development of an ICU-acquired BSI was an independent risk factor for death (OR 1·76, 95% CI 1·11–2·78, P=0·015). Finally, the severity of organ dysfunction on the day of the first BSI episode, as estimated by SOFA score, and the level of serum albumin, independently affected the outcome (OR 1·44, 95% CI 1·22–1·7, P<0·001 and OR 0·47, 95% CI 0·23–0·97, P=0·04 respectively).