Etiology and epidemiology of catheter related bloodstream infections in patients receiving home parenteral nutrition in a gastromedical center at a tertiary hospital in denmark

Clinical and microbiological characteristics of bloodstream infections caused by Enterococcus spp. within internal medicine wards: a two-year single-centre experience

Enterococcal bloodstream infections (E-BSI) constitute the second cause of Gram-positive bacterial BSI in Europe with a high rate of in-hospital mortality. Furthermore, E-BSI treatment is still challenging because of intrinsic and acquired antibiotic resistances. We conducted a retrospective, 2-year, observational, single-centre study to evaluate clinical outcome and risk factors for E-BSI mortality in internal medicine wards. 201patients with E-BSI were included in the analysis. Infection rate was 2.4/1000 days of hospital admission. Most E-BSI were hospital acquired (78.1%). The median age was 68 years. Charlson Comorbidity Index, adjusted for age, was 5 (range 4-6). Patients with E-BSI frequently had at least one invasive device, predominantly a central venous (73%) or a bladder catheter (61.7%). Enterococcus faecium accounted for 47.94% of E-BSI (resistance rate to ampicillin or vancomycin was 22.2 and 23.3%, respectively) and Enterococcus faecalis for 52.08% (resistance rate to ampicillin or vancomycin was 3.1 and 2.2%, respectively). Among all E-BSI, 25% of patients received appropriate therapy. In total, 59% of E-BSI underwent echocardiography. At the multivariate analysis, resistance to vancomycin (OR 2.09, p = 0.025), sepsis (OR 2.57, p = 0.003) and septic shock (OR 3.82, p = 0.004) was a predictor of mortality. No difference in 28-day survival was observed between appropriate or inappropriate treatment, except for endocarditis. However, E-BSI sources in clinical practices are not always properly investigated, including the rule-out of intracardiac vegetations. We did not demonstrate a difference in mortality for inappropriate therapy in the absence of endocarditis in comorbid patients with a long history of medicalization.

A New Antibiotic-Loaded Sol-Gel can Prevent Bacterial Intravenous Catheter-Related Infections

The aim of this study was to evaluate the effectiveness of a moxifloxacin-loaded organic-inorganic sol-gel (A50) by locally preventing the catheter-related bloodstream infection (CRBSI) provoked by Staphylococcus epidermidis (S. epidermidis) and the effect resulting from its hydrolytic degradation on coagulation by using a rabbit in-vivo model. A50 coating can completely inhibit growth and would locally prevent CRBSI provoked by S. epidermidis. None of the coagulation blood parameters showed a significant difference constant over time between the control catheter group and the A50-coated catheter group, despite the visible silica release resulting from physiological A50 sol-gel degradation detected in serum at least during the first week. At pathological level, foreign body reaction was present in both of types of catheter, and it was characterized by the presence of macrophages and foreign body giant cell. However, this reaction was different in each group: the A50-coated catheter group showed a higher inflammation with histiocytes, which were forming granuloma-like aggregates with an amorphous crystalline material inside, accompanied by other inflammatory cells such as plasma cells, lymphocytes and mast cells. In conclusion, A50 coating a venous catheter showed excellent bactericidal anti-biofilm response since it completely inhibited S. epidermidis biofilm development and, far from showing procoagulant effects, showed slightly anticoagulant effects.

Antibiotic Susceptibility and Therapy in Central Line Infections in Pediatric Home Parenteral Nutrition Patients

BACKGROUND

Patients receiving home parenteral nutrition (HPN) are at high-risk for central line-associated bloodstream infections (CLABSI). There are no published management guidelines, however, for the antibiotic treatment of suspected CLABSI in this population. Historical microbiology data may help inform empiric antimicrobial regimens in this population.

OBJECTIVE

The aim of the study was to describe antimicrobial resistance patterns and determine the most appropriate empiric antibiotic therapy in HPN-dependent children experiencing a community-acquired CLABSI.

METHODS

Single-center retrospective cohort study evaluating potential coverage of empiric antibiotic regimens in children on HPN who developed a community-acquired CLABSI.

RESULTS

From October 1, 2011 to September 30, 2017, there were 309 CLABSI episodes among 90 HPN-dependent children with median age 3.8 years old.Fifty-nine percent of patients carried the diagnosis of surgical short bowel syndrome. Organisms isolated during these infections included 60% Gram-positive bacteria, 34% Gram-negative bacteria, and 6% fungi. Among all staphylococcal isolates, 51% were methicillin sensitive. Among enteric Gram-negative organisms, sensitivities were piperacillin-tazobactam 71%, cefepime 97%, and meropenem 99%. Organisms were sensitive to current institutional standard therapy with vancomycin and piperacillin-tazobactam in 69% of cases compared with vancomycin and cefepime or vancomycin an meropenem in 85% and 96% of cases (both P < 0.01).

CONCLUSIONS

Empiric antimicrobial therapy for suspected CLABSI in HPN-dependent children should include therapy for methicillin-resistant staphylococci as well as enteric Gram-negative organisms. Future studies are needed to evaluate clinical outcomes based upon evidence-based antimicrobial regimens.

Epidemiology of Infectious and Noninfectious Catheter Complications in Patients Receiving Home Parenteral Nutrition: A Systematic Review and Meta-Analysis

Patients receiving parenteral nutrition (PN) as their primary source of nutrition are at high risk for both infectious and noninfectious catheter complications (catheter-related infections, catheter occlusion, and venous thrombosis). The aim of this review was to synthesize and evaluate what is known about catheter complications and prevention strategies in the PN population. Three electronic databases (Medline, Embase, and CINAHL) were screened for studies published between January 2012 and February 2019 regarding infectious and noninfectious catheter complications in patients receiving PN. Rates of infectious and noninfectious catheter complications, prevalence of causative pathogens, potential risk factors, and prevention strategies via the use of antimicrobial lock therapy (ALT) were assessed. Fifty-three catheter complication studies and 12 ALT studies were included. Studies were grouped by definition of complication: catheter-related bloodstream infections (CRBSI) or central line-associated bloodstream infections (CLABSI). Random effects summary rates per 1000 catheter days were 0.85 CRBSI episodes (95% CI 0.27-2.64) and 1.65 CLABSI episodes (95% CI 1.09-2.48). Use of taurolidine or ethanol ALT was efficacious in reducing infectious catheter complications; however, several studies had concerns for adverse mechanical complications. Potential risk factors for catheter complications were highly varied and often contradictory between studies. The rates of catheter complications were higher among catheterized patients receiving PN compared with nationally reported rates of complications in all catheterized patients. Risk factors for catheter complications need to be better understood for targeted prophylactic use of ALT. Future studies are warranted; however, they should be conducted using more standardized definitions and criteria.

Epidemiology and risk factors for invasive fungal infections during induction chemotherapy for newly diagnosed acute myeloid leukemia: A retrospective cohort study

This study investigated the epidemiology and risk factors associated with invasive fungal infections (IFIs) during induction chemotherapy in a cohort of Taiwanese patients with newly-diagnosed acute myeloid leukemia (AML). IFIs are a significant complication in the management of immunocompromised cancer patients; such infections are associated with a high incidence of morbidity and mortality, particularly in many South-Asian countries, where IFI rates are increasing. We retrospectively analyzed IFI incidence data from 105 patients with newly diagnosed AML at a single center undergoing their first course of induction chemotherapy without primary antifungal prophylaxis between November 2008 and December 2014. Of 21 cases documented as proven/provable IFIs 16 (76%) were invasive aspergillosis, 2 (10%) were mucormycosis infections, and 3 (14%) were proven yeast infections. The lung was the most commonly affected site (n = 16; 76%); 2 patients (10%) developed fungal sinusitis. IFI cases were more often males (P = 0.020). In multivariate analysis, patients with neutropenia lasting>30 days were more than twice as likely to develop IFI (OR, 2.24 [95% CI, 2.81-31.11], P<0.001). We also confirmed patients with smoker and receiving parenteral nutrition during chemotherapy were significant associated with IFIs. Our findings suggest that antifungal prophylaxis should be considered for patients with AML during induction chemotherapy, particularly in patients from Southeastern Asia, an area of potentially high IFI rates. We recommend that clinicians determine which patients receiving induction chemotherapy for AML are at high risk of developing IFI, to allow for targeted therapeutic prophylaxis.

The optimal ethanol lock therapy regimen for treatment of biofilm-associated catheter infections: an in-vitro study

BACKGROUND

Ethanol-based lock therapy (LT) solutions are used as an alternative to antibiotics for the conservative management of catheter-related bloodstream infection. However, no clear consensus on regimen or dose has been reached.

AIM

To find the ethanol-based lock solution containing a sufficiently low concentration of ethanol for reduction of the metabolic activity of bacterial and fungal biofilms.

METHODS

Using an in-vitro model, three concentrations of ethanol (25%, 40%, 70%) were tested, with and without 60 IU of heparin, at six different time-points and against 24 h preformed biofilms of Staphylococcus aureus ATCC29213, Staphylococcus epidermidis (clinical isolate), Enterococcus faecalis ATCC33186, Candida albicans ATCC14058, and Escherichia coli ATCC25922. The reduction in the metabolic activity of the biofilm was measured using the tetrazolium salt assay and LT was considered to be successful when metabolic activity fell by >90%. Regrowth inhibition was then tested within 24 h and seven days after each LT regimen only at the ethanol concentration of the most successful LT regimen.

FINDINGS

The most successful LT was achieved with 40% ethanol + 60 IU of heparin only at 24, 72, and 24 h for seven-day regimens (P < 0.05). However, none of the regimens reached 45% RI within seven days of therapy.

CONCLUSION

According to our in-vitro data, an ethanol-based lock solution with 40% ethanol + 60 IU heparin administered daily for 72 h is sufficient to almost eradicate the metabolic activity of bacterial and fungal biofilms. Future studies are needed to study cell regrowth after LT.

Catheter-related blood stream infection in patients receiving long-term home parenteral nutrition: Tertiary care hospital experience in Saudi Arabia

BACKGROUND/AIM

Parenteral nutrition (PN) is a lifesaving therapy for patients with many severe conditions, including intestinal failure. Some patients require long-term PN therapy, which makes home parenteral nutrition (HPN) an attractive option to improve the quality of life. Among the most common and serious complications observed in these patients are catheter-related blood stream infections (CRBSIs). The aim of our study is to determine the frequency of CRBSI among patients receiving long-term HPN.

PATIENTS AND METHODS

A retrospective chart review was conducted for patients enrolled in the HPN program between 2006 and 2012. Data on the demographic characteristics, indications and duration of PN therapy, catheter type, number of admissions because of CRBSI, and blood culture results were recorded.

RESULTS

Eight pediatric patients were included (mean age of 3.5 years at the start of HPN). Microvillus inclusive disease was noted in 50% of these patients, and 75% of them received HPN under parents' care. CRBSI resulted in 60 admissions with a median of 182 days of hospital stay and 74 changes of central venous catheters. The rate of CRBSI was 2.9 per 1000 catheter days. Staphylococcus species were the most prevalent pathogens (32%), followed by Klebsiella pneumoniae (5%).

CONCLUSION

In this small group of HPN patients, the BSI rate was 2.9 infections per 1000 catheter days, and most common causative organisms were Staphylococcus species. We believe that a well-established training program for caregivers can reduce the rate of infectious complications associated with long-term PN support.

Catheter-related blood stream infection caused by Raoultella ornithinolytica

Raoultella spp. representatives are Gram-negative capsulated, nonmotile rods. These bacteria are found in the natural environment: plants, water, soil and insects. R. ornithinolytica is one of the three species of Raoultella. R. ornithinolytica is the only species within the genus which has the ability to produce ornithine decarboxylase. Human infections related to R. ornithinolytica are exceedingly rare. The present case report describes catheter-related blood stream infection caused by R. ornithinolytica and successfully treated with antibiotic therapy.

Epidemiology and risk factors for bloodstream infections in a home parenteral nutrition program

BACKGROUND

An increasing number of patients with intestinal failure are receiving home parenteral nutrition (HPN). Associated complications include bloodstream infections (BSIs), but data on rates and risk factors for HPN-related BSIs are scarce.

METHODS

A retrospective review was conducted of patients enrolled in the regional HPN program between 2001 and 2008. Demographic information and data on indication for HPN, duration of PN therapy, type and date of insertion of central venous access device, and blood culture results were recorded.

RESULTS

In total, 155 patients (165 courses of HPN) were included for a total of 45,876 catheter days. The mean patient age was 49 years, and 105 (64%) patients were female. A total of 105 organisms were cultured from 93 distinct episodes of BSIs. The rate of BSI was found to be 2.0 per 1000 catheter days, but excluding BSIs with a single positive culture of coagulase-negative staphylococcus and diphtheroid bacilli, the rate of infection was 1.4 per 1000 catheter days. Male sex and underlying malignancy were significant predictors of BSI, with hazard ratios of 1.69 (95% confidence interval [CI], 1.14-2.60; P = .009) and 2.38 (95% CI, 1.53-3.50; P < .001).

CONCLUSION

In a large heterogeneous group of HPN patients, the BSI rate ranged between 1.4 and 2.0 infections per 1000 catheter days. Isolated organisms were similar to those found in hospitalized patients. Male sex and underlying malignancy were significant risk factors for BSI. These high-risk patients are likely to benefit from interventions aimed at reducing BSIs.