Catheter-related bloodstream infections

Auranofin coated catheters inhibit bacterial and fungal biofilms in a murine subcutaneous model

Microbe entry through catheter ports can lead to biofilm accumulation and complications from catheter-related bloodstream infection and ultimately require antimicrobial treatment and catheter replacement. Although strides have been made with microbial prevention by applying standardized antiseptic techniques during catheter implantation, both bacterial and fungal microbes can present health risks to already sick individuals. To reduce microbial adhesion, murine and human catheters were coated with polyurethane and auranofin using a dip coating method and compared to non-coated materials. Upon passage of fluid through the coated material in vitro, flow dynamics were not impacted. The unique antimicrobial properties of the coating material auranofin has shown inhibitory activity against bacteria such as Staphylococcus aureus and fungi such as Candida albicans. Auranofin coating on catheters at 10mg/mL reduced C. albicans accumulation in vitro from 2.0 x 10⁸ to 7.8 x 10⁵ CFU for mouse catheters and from 1.6 x 10⁷ to 2.8 x 10⁶ for human catheters, showing an impact to mature biofilms. Assessment of a dual microbe biofilm on auranofin-coated catheters resulted in a 2-log reduction in S. aureus and a 3-log reduction in C. albicans compared to uncoated catheters. In vivo assessment in a murine subcutaneous model demonstrated that catheters coated with 10 mg/mL auranofin reduced independent S. aureus and C. albicans accumulation by 4-log and 1-log, respectively, compared to non-coated catheters. In conclusion, the auranofin-coated catheters demonstrate proficiency at inhibiting multiple pathogens by decreasing S. aureus and C. albicans biofilm accumulation.

Antiseptic solutions for skin preparation during central catheter insertion in neonates

BACKGROUND

Central venous catheters (CVC) are associated with potentially dangerous complications such as thromboses, pericardial effusions, extravasation, and infections in neonates. Indwelling catheters are amongst the main risk factors for nosocomial infections. The use of skin antiseptics during the preparation for central catheter insertion may prevent catheter-related bloodstream infections (CRBSI) and central line-associated bloodstream infections (CLABSI). However, it is still not clear which antiseptic solution is the best to prevent infection with minimal side effects.

OBJECTIVES

To systematically evaluate the safety and efficacy of different antiseptic solutions in preventing CRBSI and other related outcomes in neonates with CVC.

SEARCH METHODS

We searched CENTRAL, MEDLINE, Embase, and trial registries up to 22 April 2022. We checked reference lists of included trials and systematic reviews that related to the intervention or population examined in this Cochrane Review.  SELECTION CRITERIA: Randomised controlled trials (RCTs) or cluster-RCTs were eligible for inclusion in this review if they were performed in the neonatal intensive care unit (NICU), and were comparing any antiseptic solution (single or in combination) against any other type of antiseptic solution or no antiseptic solution or placebo in preparation for central catheter insertion. We excluded cross-over trials and quasi-RCTs.

DATA COLLECTION AND ANALYSIS

We used the standard methods from Cochrane Neonatal. We used the GRADE approach to assess the certainty of the evidence.

MAIN RESULTS

We included three trials that had two different comparisons: 2% chlorhexidine in 70% isopropyl alcohol (CHG-IPA) versus 10% povidone-iodine (PI) (two trials); and CHG-IPA versus 2% chlorhexidine in aqueous solution (CHG-A) (one trial). A total of 466 neonates from level III NICUs were evaluated. All included trials were at high risk of bias. The certainty of the evidence for the primary and some important secondary outcomes ranged from very low to moderate. There were no included trials that compared antiseptic skin solutions with no antiseptic solution or placebo. CHG-IPA versus 10% PI Compared to PI, CHG-IPA may result in little to no difference in CRBSI (risk ratio (RR) 1.32, 95% confidence interval (CI) 0.53 to 3.25; risk difference (RD) 0.01, 95% CI -0.03 to 0.06; 352 infants, 2 trials, low-certainty evidence) and all-cause mortality (RR 0.88, 95% CI 0.46 to 1.68; RD -0.01, 95% CI -0.08 to 0.06; 304 infants, 1 trial, low-certainty evidence). The evidence is very uncertain about the effect of CHG-IPA on CLABSI (RR 1.00, 95% CI 0.07 to 15.08; RD 0.00, 95% CI -0.11 to 0.11; 48 infants, 1 trial; very low-certainty evidence) and chemical burns (RR 1.04, 95% CI 0.24 to 4.48; RD 0.00, 95% CI -0.03 to 0.03; 352 infants, 2 trials, very low-certainty evidence), compared to PI. Based on a single trial, infants receiving CHG-IPA appeared less likely to develop thyroid dysfunction compared to PI (RR 0.05, 95% CI 0.00 to 0.85; RD -0.06, 95% CI -0.10 to -0.02; number needed to treat for an additional harmful outcome (NNTH) 17, 95% CI 10 to 50; 304 infants). Neither of the two included trials assessed the outcome of premature central line removal or the proportion of infants or catheters with exit-site infection. CHG-IPA versus CHG-A The evidence suggests CHG-IPA may result in little to no difference in the rate of proven CRBSI when applied on the skin of neonates prior to central line insertion (RR 0.80, 95% CI 0.34 to 1.87; RD -0.05, 95% CI -0.22 to 0.13; 106 infants, 1 trial, low-certainty evidence) and CLABSI (RR 1.14, 95% CI 0.34 to 3.84; RD 0.02, 95% CI -0.12 to 0.15; 106 infants, 1 trial, low-certainty evidence), compared to CHG-A. Compared to CHG-A, CHG-IPA probably results in little to no difference in premature catheter removal (RR 0.91, 95% CI 0.26 to 3.19; RD -0.01, 95% CI -0.15 to 0.13; 106 infants, 1 trial, moderate-certainty evidence) and chemical burns (RR 0.98, 95% CI 0.47 to 2.03; RD -0.01, 95% CI -0.20 to 0.18; 114 infants, 1 trial, moderate-certainty evidence). No trial assessed the outcome of all-cause mortality and the proportion of infants or catheters with exit-site infection.

AUTHORS' CONCLUSIONS

Based on current evidence, compared to PI, CHG-IPA may result in little to no difference in CRBSI and mortality. The evidence is very uncertain about the effect of CHG-IPA on CLABSI and chemical burns. One trial showed a statistically significant increase in thyroid dysfunction with the use of PI compared to CHG-IPA. The evidence suggests CHG-IPA may result in little to no difference in the rate of proven CRBSI and CLABSI when applied on the skin of neonates prior to central line insertion. Compared to CHG-A, CHG-IPA probably results in little to no difference in chemical burns and premature catheter removal. Further trials that compare different antiseptic solutions are required, especially in low- and middle-income countries, before stronger conclusions can be made.

Randomized clinical trial: Long-term Staphylococcus aureus decolonization in patients on home parenteral nutrition

BACKGROUND & AIMS

Staphylococcus aureus decolonization has proven successful in prevention of S. aureus infections and is a key strategy to maintain venous access and avoid hospitalization in patients receiving home parenteral nutrition (HPN). We aimed to determine the most effective and safe long-term S. aureus decolonization regimen.

METHODS

A randomized, open-label, multicenter clinical trial was conducted. Adult intestinal failure patients with HPN support and carrying S. aureus were randomly assigned to a 'continuous suppression' (CS) strategy, a repeated chronic topical antibiotic treatment or a 'search and destroy' (SD) strategy, a short and systemic antibiotic treatment. Primary outcome was the proportion of patients in whom S. aureus was totally eradicated during a 1-year period. Secondary outcomes included risk factors for decolonization failure and S. aureus infections, antimicrobial resistance, adverse events, patient compliance and cost-effectivity.

RESULTS

63 participants were included (CS 31; SD 32). The mean 1-year S. aureus decolonization rate was 61% (95% CI 44, 75) for the CS group and 39% (95% CI 25, 56) for the SD group with an OR of 2.38 (95% CI 0.92, 6.11, P = 0.07). More adverse effects occurred in the SD group (P = 0.01). Predictors for eradication failure were a S. aureus positive caregiver and presence of a (gastro)enterostomy.

CONCLUSION

We did not demonstrate an increased efficacy of a short and systemic S. aureus decolonization strategy over a continuous topical suppression treatment. The latter may be the best option for HPN patients as it achieved a higher long-term decolonization rate and was well-tolerated (NCT03173053).

Incidence and short-term outcomes of central line-related bloodstream infection in patients admitted to the emergency department: a single-center retrospective study

Central line-related bloodstream infection (CRBSI) is a common complication during hospital admissions; however, there is insufficient data regarding CRBSI in the emergency department. Therefore, we evaluated the incidence and clinical impact of CRBSI using a single-center retrospective study to analyze medical data of 2189 adult patients (median age: 65 years, 58.8% males) who underwent central line insertion in ED from 2013 to 2015. CRBSI was defined if the same pathogens were identified at peripheral and catheter tips or the differential time to positivity was > 2 h. CRBSI-related in-hospital mortality and risk factors were evaluated. CRBSI occurred in 80 patients (3.7%), of which 51 survived and 29 died; those with CRBSI had higher incidence of subclavian vein insertion and retry rates. Staphylococcus epidermidis was the most common pathogen, followed by Staphylococcus aureus, Enterococcus faecium, and Escherichia coli. Using multivariate analysis, we found that CRBSI development was an independent risk factor for in-hospital mortality (adjusted odds ratio: 1.93, 95% confidence intervals: 1.19-3.14, p < 0.01). Our findings suggest that CRBSI after central line insertion in the emergency department is common and associated with poor outcomes. Infection prevention and management measures to reduce CRBSI incidence are essential to improve clinical outcomes.

Multicentre surveillance of epidemiologically important pathogens causing nosocomial bloodstream infections and pneumonia trials in Brazilian adult intensive care units

Introduction. Healthcare-associated infections (HAIs) are the most recurrent adverse event in hospitals worldwide and represent an important public health problem.Gap statement. There are a paucity of multicentric data describing severe HAIs such as bloodstream infection (BSI) and pneumonia in Brazil.Aim. To provide an up-to-date picture of the extent and patterns of HAIs in adult intensive care units (ICUs), as well as to identify variables associated with the risk of development of severe infections.Methodology. Point prevalence surveys were conducted using standardized protocols in 35 ICUs from Minas Gerais state, Brazil. Medical records of eligible inpatients at or before 8 am on the survey day were reviewed to identify HAIs present at the time of the survey. A matched-pairs case-control study was performed on a total of 66 pairs for BSI and 115 pairs for pneumonia according to the selection criteria developed.Results. Overall, 171 patients (45.7%) had at least one HAI, with most (78.4%) acquired in the ICU. These patients presented a total of 240 infections; including 123 pneumonia (51.3%) and 66 BSI (27.5%), and 78.9 and 80.3 %, respectively, were acquired in the ICU. Their aetiology showed a predominance of Gram-negative bacteria versus Gram-positive bacteria (48.9 versus 43.3 %), with Acinetobacter baumannii (13.7%) and Pseudomonas aeruginosa (12.8%) being prominent. One striking observation from our data was the higher prevalence of Staphylococcus aureus (14.5%) and coagulase-negative staphylococci (10.2%) observed in the overall HAIs.Conclusion. A high severe ICU-acquired HAI burden was found when compared with findings from other low- and middle-income countries. These data can be utilized for better planning of nosocomial infection surveillance programmes in our hospitals.

Pulmonary hypertension at admission predicts ICU mortality in elderly critically ill with severe COVID-19 pneumonia: retrospective cohort study

BACKGROUND

Point-of-care ultrasound (POCUS) is a useful diagnostic tool for non-invasive assessment of critically ill patients. Mortality of elderly patients with COVID-19 pneumonia is high and there is still scarcity of definitive predictors. Aim of our study was to assess the prediction value of combined lung and heart POCUS data on mortality of elderly critically ill patients with severe COVID-19 pneumonia.

METHODS

This was a retrospective observational study. Data of patients older than 70 years, with severe COVID-19 pneumonia admitted to mixed 25-bed, level 3, intensive care unit (ICU) was analyzed retrospectively. POCUS was performed at admission; our parameters of interest were pulmonary artery systolic pressure (PASP) and presence of diffuse B-line pattern (B-pattern) on lung ultrasound.

RESULTS

Between October 2020 and March 2021, 117 patients aged 70 years or more (average age 77 ± 5 years) were included. Average length of ICU stay was 10.7 ± 8.9 days. High-flow oxygenation, non-invasive ventilation and invasive mechanical ventilation were at some point used to support 36/117 (31%), 39/117 (33%) and 75/117 (64%) patients respectively. ICU mortality was 50.9%. ICU stay was shorter in survivors (8.8 ± 8.3 vs 12.6 ± 9.3 days, p = 0.02). PASP was lower in ICU survivors (32.5 ± 9.8 vs. 40.4 ± 14.3 mmHg, p = 0.024). B-pattern was more often detected in non-survivors (35/59 (59%) vs. 19/58 (33%), p = 0.005). PASP and B-pattern at admission, and also mechanical ventilation and development of VAP, were univariate predictors of mortality. PASP at admission was an independent predictor of ICU (OR 1.061, 95%CI 1.003-1.124, p = 0.039) and hospital (OR 1.073, 95%CI 1.003-1.146, p = 0.039) mortality.

CONCLUSIONS

Pulmonary artery systolic pressure at admission is an independent predictor of ICU and hospital mortality of elderly patients with severe COVID-19 pneumonia.

The predictors of catheter-related bloodstream infections in patients undergoing hemodialysis: A single center experience

BACKGROUND

Here we aimed to investigate the predictors of catheter-related bloodstream infections (CRBSI) in patients with acute kidney injury or chronic kidney disease who required renal replacement therapy through a non-tunneled hemodialysis catheter.

METHODS

A total of 111 patients who received non-tunneled hemodialysis catheters were retrospectively evaluated. Patients were divided into two groups; those who developed CRBSI and those who did not. Patient's demographic data, laboratory results at admission, information regarding catheter infections, and culture results were obtained from electronic medical records.

RESULTS

The mean age of the patients was 64 ± 16 years, and 51 of them were male. CRBSI occurred in 14 patients (12.6%). Admission serum albumin level (OR: 0.119, 95% CI: 0.019-0.756, p = 0.024), admission mean platelet volume (OR: 2.207, 95% CI: 1.188-4.100, p = 0.012) and catheter duration (OR: 1.580, 95% CI: 1.210-2.064, p = 0.001) were independent predictors for the CRBSI development. ROC curve analysis demonstrated that a catheter duration of 22 days was predictive for presence of CRBSI (78% sensitivity, 76% specificity, AUC: 0.825, 95% CI: 0.724-0.925, p < 0.001).

CONCLUSIONS

Prolonged catheter duration, low serum albumin, and high mean platelet volume independently predict the development of CRBSI in patients undergoing hemodialysis for acute kidney injury or chronic kidney disease.

Crystal violet-based assay for the assessment of bacterial biofilm formation in medical tubing

Crystal violet-based assay is widely used to evaluate the early stages of bacterial biofilm formation. Here, we modified it to study biofilm formation in medical tubing. While cost-effective and requiring no sophisticated equipment, our method provided quantitative and qualitative distinctions between the ability of four bacterial strains to colonize PVC catheters.

Design of Thermoplastic Polyurethanes with Conferred Antibacterial, Mechanical, and Cytotoxic Properties for Catheter Application

Thermoplastic polyurethanes (TPUs) are proposed as suitable solution for the fabrication of biocompatible catheters with appropriate mechanical parameters and confirmed antibacterial and cytocompatible properties. For this purpose, a series of quaternary ammonium salts (QASs) and quaternary phosphonium salts (QPSs) based monomers were prepared followed by the determination of their minimal inhibitory concentrations (MICs) against Gram-positive Staphylococcus aureus (S. aureus) and Gram-negative Pseudomonas aeruginosa (P. aeruginosa). A combination of the most active ammonium (QAS-C₁₄) and phosphonium (QPS-TOP) salts led to a MIC down to 2.4 μg/mL against S. aureus and 9 μg/mL against P. aeruginosa, corroborating the existence of a synergistic effect. These quaternary onium salt (QOS) units were successfully incorporated along the polymer chain, as part of a two-step synthesis approach. The resulting TPU-QOS materials were subsequently characterized through thermal, mechanical, and surface analyses. TPU-Mix (combining the most active QAS-C₁₄ and QPS-TOP units) showed the highest antibacterial efficiency, confirming the synergistic effect between both QOS groups. Finally, an MTT assay on the SiHa cell line revealed the low cytotoxicity level of these polymeric films, making these materials suitable for biomedical application. To go one step further in the preindustrialization approach, proof of concept regarding the catheter prototype fabrication based on TPU-QAS/QPS was validated by extrusion.

The comparative accuracy of pooled vs. individual blood culture sampling methods for diagnosis of catheter-related bloodstream infection

Background

Catheter-related bloodstream infection (CRBSI) is associated with increased morbidity, mortality, and cost of treatment in critically ill patients. A differential time to positivity (DTP) of 120 min or more between blood cultures obtained through the catheter vs. peripheral vein is an indicator of CRBSI with high sensitivity and specificity. However, it is no clear whether pooled sampling would be as efficient as individual sampling in order to reduce costs, contamination, or anemia.

Methods

This was a prospective diagnostic study conducted at the medical ICU and semi-ICU of Khon Kaen University’s Srinagarind Hospital in Thailand from May 2020 to November 2021. Fifty patients with triple-lumen central venous catheters (CVCs) who were clinically suspected of CRBSI were enrolled. 15 mL of blood was drawn through each catheter lumen, 10 mL of which was inoculated into three blood culture bottles, and the remaining 5 mL was pooled into a single bottle. Sensitivity, specificity, accuracy, and time to positivity of the pooled blood cultures were calculated using individual blood cultures as a reference.

Results

Of the 50 patients enrolled, 14 (28%) were diagnosed with CRBSI, 57.9% of whom were infected with gram-negative bacteria as the causative pathogen (57.9%). Extensively drug-resistant (XDR) Klebsiella pneumoniae was the most common organism. Sensitivity and specificity of the pooled blood sampling method were 69.23% (95% CI [0.44–0.94]) and 97.3% (95% CI [0.92–1.02]), respectively. The area under the ROC curve (AUC) was 0.83 (95% CI [0.68–0.99]). A paired T-Test to compare time to positivity of the pooled blood bottle and the first positive culture from the individual bottles indicated statistical significance (14.9 and 12.4 h, respectively). The mean difference was 2.5 [0.9–4.1] h, with a 95% CI and a p-value of 0.006.

Conclusion

Pooled blood sampling results in a lower sensitivity and longer time to positivity for CRBSI diagnosis in patients with triple-lumen CVCs than individual lumen sampling.

Trial registration Retrospectively registered at Thai Clinical Trials Registry. The study was reviewed and approved on 08/03/2022. TCTR identification number is TCTR20220308002

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07605-x.

How to manage central venous catheter-related bloodstream infections due to Gram-negative bacilli?

PURPOSE OF REVIEW

The aim of this study was to review recent data evaluating the management of central venous catheter-related bloodstream infection due to Gram-negative bacilli (GNB).

RECENT FINDINGS

The incidence of GNB catheter-related bloodstream infection (CRBSI) has been increasing considerably in the last years, and this has raised a concern due to the high reported rate of multidrug-resistant in these infections what poses a considerable challenge for effective treatment. However, there are no specific guidelines for the management of GNB-CRBSI and optimal treatment duration has not been clearly defined. Recent studies have shown that the risk for complications is clearly different to what is stablished for Staphylococcus aureus . Therefore, a short course of antibiotic therapy might be effective once the central venous catheter (CVC) has been removed and the monitoring complications through control blood cultures or echocardiography seem to be less helpful in GNB CRBSI.

SUMMARY

The incidence of GNB CRBSI has been increasing considerably in the last years; this has raised a concern due to the high reported rate of MDR in these infections what poses a considerable challenge for effective treatment. However, there are no specific guidelines for the management of GNB-CRBSI and optimal treatment duration has not been clearly defined. Recent studies have shown that the risk for complications is clearly different to what is stablished for S. aureus . Therefore, a short course of antibiotic therapy might be effective once the CVC has been removed and the monitoring complications through control blood cultures or echocardiography seem to be less helpful in GNB-CRBSI.

Biofilm formation and antibiotic resistance among Coagulase Negative Staphylococcus species isolated from central venous catheters of intensive care unit patients

PURPOSE

This study was conducted to determine the biofilm formation of coagulase negative Staphylococcus species (CoNS) isolated from patients with catheter related blood stream infection (CRBSI) and colonized central venous catheters (CVC) and their antibiotic susceptibility patterns and in situ biofilm formation of CVC tips.

METHODS

Eighty-two CoNS isolated from intensive care unit (ICU) patients with CRBSI (n ​= ​8) or colonized CVC (n ​= ​74) were included. Species identification and antibiotic susceptibility test were done. All isolates were screened for biofilm formation using crystal violet and 3-(4,5-dimethylthiazole-2-yl)-2-5-diphenyl-2H-tetrazolium bromide (MTT) assays and categorized as strong or moderate biofilm formers. CVC tips were subjected to crystal violet stain and scanning electron microscopy (SEM) to detect in-situ biofilm formation.

RESULTS

Staphylococcus haemolyticus (n ​= ​34; 41%) was the commonest to cause both CRBSI and CVC colonization. All 82 CoNS produced biofilms. Among them 77 (93.90%) were strong biofilm formers including all from CRBSI patients and 05 (6.10%) were moderate biofilm formers as detected by both methods. SEM showed bacteria adhered to surfaces of CVC tips with microbial-aggregates embedded in extracellular matrix. Mean crystal violet absorbance of CVC from CRBSI patients (0.6628) was significantly higher than colonized CVC (mean value 0.5592) (p ​= ​0.030). S. haemolyticus showed higher resistance to cloxacillin compared to other CoNS (p ​= ​0.039).

CONCLUSION

Majority of CoNS isolated were strong biofilm formers. In-situ biofilm formation on CVC tips were significantly evident in CRBSI patients compared to CVC colonized patients. S. haemolyticus is the commonest to cause both CRBSI and CVC colonization and shows significantly higher cloxacillin resistance rate.

Antimicrobial persistence of two alcoholic preoperative skin preparation solutions

BACKGROUND

Normal skin flora and suboptimal skin antisepsis are the primary drivers of healthcare-associated infections (HAIs). Antimicrobial persistence of preoperative skin preparation is necessary to limit microorganisms on the skin and help minimize their entry into an incision or device-insertion site after application.

AIM

To assess the antimicrobial persistence of two preoperative skin preparation solutions.

METHODS

A randomized, single-centre, partially blinded, clinical study was conducted in 103 healthy volunteers to evaluate the persistent antimicrobial properties of BD ChloraPrep™ (2% w/v chlorhexidine gluconate [CHG] + 70% v/v isopropyl alcohol [IPA]) and BD PurPrep™ (8.3% w/w povidone-iodine [PVP-I] + 72.5% w/w IPA) skin preparations out to 7 days and 96 hours, respectively, on abdomen and groin testing sites. An additional 32 healthy volunteers participated in a neutralization procedure to ensure the study recovery solution was non-toxic to microorganisms, and a spore-recovery procedure to demonstrate that microorganisms could be successfully recovered from the PVP-I+IPA film-forming product.

RESULTS

Both CHG+IPA and PVP-I+IPA produced a mean bacterial log₁₀ reduction >2 and >3 on the abdomen and groin, respectively, 10 minutes after application. CHG+IPA maintained antimicrobial persistence out to 7 days post-application, while PVP-I+IPA maintained antimicrobial persistence out to 96 hours post-application, the longest timepoint selected for this product.

CONCLUSION

CHG+IPA and PVP-I+IPA were both found to be effective persistent antiseptic skin preparations. Overall, skin irritation was uncommon, and only 1 adverse event occurred following product application, which was not considered product related but was considered procedure related.

Distribution of mecA and qacA/B genes among coagulase negative staphylococci isolated from central venous catheters of intensive care unit patients

PURPOSE

This study was designed to detect the prevalence of antibiotic and antiseptic resistance genes, mecA and qacA/B in coagulase negative Staphylococcus (CoNS) species isolated from intensive care unit patients with catheter related blood stream infections (CRBSI) or colonized central venous catheters (CVC).

METHODS

Consecutive CoNS isolates from ICU patients with CRBSI or colonized central venous catheters were speciated and antibiotic susceptibilities were determined. The mecA and qacA/B genes were detected by polymerase chain reaction.

RESULTS

Eighty-two CoNS isolates from ICU patients with CRBSI (n ​= ​8) or colonized CVC (n ​= ​74) were included. The mecA gene was detected in 62 CoNS isolates (76%). The commonest species isolated was S. haemolyticus (n ​= ​34; 41%) and 30 of these possessed mecA which was significantly higher compared to other CoNS species (p ​= ​0.036). The qacA/B gene was detected in 13 (16%) isolates. Eleven (13%) CoNS had both genes. A significant association was seen with the presence of mecA and resistance to cloxacillin (p ​< ​0.001) and erythromycin (p ​= ​0.046). Presence of qacA/B (p ​= ​0.007) or both mecA and qacA/B (p ​= ​0.014) was associated with a higher resistance to clindamycin.

CONCLUSION

A considerably high prevalence of mecA and qacA/B genes as well as co-existence of both genes is noted among the CoNS isolated from ICU patients. This indicates the need of taking prompt actions in hospital acquired infection prevention including continuous surveillance.

Catheter-related bloodstream infections in infants hospitalized in neonatal intensive care units: a single center study

Sepsis in neonates carries a high morbidity and mortality rate and is among the most feared complications in the neonatal intensive care unit (NICU). Catheter-related bloodstream infections (CRBSI) are a common etiology of late-onset sepsis. The aim of this study was to compare risk factors and characteristics between patients according to the type of catheter that was utilized and according to birth weight classification. The study included 51 newborns with confirmed CRBSI, which were hospitalized in our level 3 NICU between January 2017 and December 2018. The study population was stratified according to the type of venous catheter utilized (peripherally inserted central catheter, central venous catheter (CVC), and peripheral venous catheter). Infants with low birth weight and those who required prolonged parenteral nutrition were most likely to develop CRBSI in our study group. The type of venous catheter was not associated with blood culture results. Also, infants with a birth weight of < 1500 g and > 1500 g did not differ in sepsis etiology. Further research is required to assess venous catheters relative risk of causing sepsis and if the outcome can be traced back specifically to catheter type or patient characteristics.

Single-dose prophylactic ibuprofen therapy for patent ductus arteriosus in preterm infants

This study aimed to evaluate the short-term morbidities and efficacy of single-dose prophylactic intravenous ibuprofen for patent ductus arteriosus (PDA) on the first day of life in preterm infants. Data of 69 preterm infants with birth weight < 1250 g and gestational age < 30 weeks admitted to the neonatal intensive care unit were analyzed. Of these, 37 infants were assigned to the prophylactic treatment (PT) group and 32 were assigned to the nonprophylactic treatment (non-PT) group. Only the PT group administered intravenous ibuprofen (10 mg/kg) once within 6 hours after birth. Until postnatal day 7, ductal closure occurred in 11 (34.4%) infants in the non-PT group, and in 35 (94.6%) infants in the PT group, of which 30 (81.1%) infants had ductal closure on postnatal day 1. There were 2 (5.4%) infants in the PT group and 9 (28.1%) in the non-PT group who needed ibuprofen treatment due to moderate-to-large PDA after postnatal day 7. Preterm infants in the PT group were less likely to develop an intraventricular hemorrhage (≥grade 2) (adjusted odds ratio 0.007, 95% confidence interval 0.01-0.45), had a shorter duration of invasive ventilatory support and central venous catheter, and earlier postnatal age to achieve feeding of 50 and 100 mL/kg/day compared with those in the non-PT group. Single-dose prophylactic intravenous ibuprofen on the first day of life decreased the occurrence of a persistent PDA and intraventricular hemorrhage (≥grade 2), and reduced the duration of invasive ventilatory support, central venous catheter use, and hospital stay.

What Is New in the Anti–Pseudomonas aeruginosa Clinical Development Pipeline Since the 2017 WHO Alert?

The spread of antibiotic-resistant bacteria poses a substantial threat to morbidity and mortality worldwide. Carbapenem-resistant Pseudomonas aeruginosa (CRPA) are considered “critical-priority” bacteria by the World Health Organization (WHO) since 2017 taking into account criteria such as patient mortality, global burden disease, and worldwide trend of multi-drug resistance (MDR). Indeed P. aeruginosa can be particularly difficult to eliminate from patients due to its combinatory antibiotic resistance, multifactorial virulence, and ability to over-adapt in a dynamic way. Research is active, but the course to a validated efficacy of a new treatment is still long and uncertain. What is new in the anti–P. aeruginosa clinical development pipeline since the 2017 WHO alert? This review focuses on new solutions for P. aeruginosa infections that are in active clinical development, i.e., currently being tested in humans and may be approved for patients in the coming years. Among 18 drugs of interest in December 2021 anti–P. aeruginosa development pipeline described here, only one new combination of β-lactam/β-lactamase inhibitor is in phase III trial. Derivatives of existing antibiotics considered as “traditional agents” are over-represented. Diverse “non-traditional agents” including bacteriophages, iron mimetic/chelator, and anti-virulence factors are significantly represented but unfortunately still in early clinical stages. Despite decade of efforts, there is no vaccine currently in clinical development to prevent P. aeruginosa infections. Studying pipeline anti–P. aeruginosa since 2017 up to now shows how to provide a new treatment for patients can be a difficult task. Given the process duration, the clinical pipeline remains unsatisfactory leading best case to the approval of new antibacterial drugs that treat CRPA in several years. Beyond investment needed to build a robust pipeline, the Community needs to reinvent medicine with new strategies of development to avoid the disaster. Among “non-traditional agents”, anti-virulence strategy may have the potential through novel and non-killing modes of action to reduce the selective pressure responsible of MDR.

Can inverse probability treatment weighting (IPTW) be used to assess differences of CRBSI rates between non-tunneled femoral and jugular CVCs in PICU patients?

BACKGROUND

In children in the ICU, catheter-related bloodstream infections (CRBSI) have also been linked to mortality, morbidity, and healthcare costs. Although CRBSI poses many potential risks, including the need to avoid femoral access, there is debate regarding whether jugular access is preferable to femoral access in adults. Study reports support both perspectives. There is no consensus in meta-analyses. Children have yet to be examined in depth. Based on compliance with the central line bundle check lists, we aim to determine CRBSI risk in pediatric intensive care units for patients with non-tunneled femoral and internal jugular venous access.

METHODS

A retrospective cohort study was conducted on patients with central venous catheters in the pediatric ICU of King Abdulaziz University Hospital between January 1st, 2017 and January 30th, 2018. For the post-match balance, we use a standardized mean difference of less than 0.1 after inverse probability treatment weighting for all baseline covariates, and then we draw causal conclusions. As a final step, the Rosenbaum sensitivity test was applied to see if any bias influenced the results.

RESULTS

We recorded 145 central lines and 1463 central line days with 49 femoral accesses (33.79%) and 96 internal jugular accesses (66.21%). CRBSI per 1000 central line days are 4.10, along with standardized infections of 3.16. CRBSI risk differed between non-tunneled femoral vein access and internal jugular vein access by 0.074 (- 0.021, 0.167), P-value 0.06, and relative risk was 4.67 (0.87-25.05). Using our model, the actual probability was 4.14% (0.01-0.074) and the counterfactual probability was 2.79% (- 0.006, 0.062). An unobserved confounding factor was not identified in the sensitivity analysis.

CONCLUSIONS

So long as the central line bundle is maintained, a femoral line does not increase the risk of CRBSI. Causation can be determined through propensity score weighting, as this is a trustworthy method of estimating causality. There is no better way to gain further insight in this regard than through the use of randomized, double-blinded, multicenter studies.

Particle-Mediated Histotripsy for the Targeted Treatment of Intraluminal Biofilms in Catheter-Based Medical Devices

Objective. This paper is an initial work towards developing particle-mediated histotripsy (PMH) as a novel method of treating catheter-based medical device (CBMD) intraluminal biofilms. Impact Statement. CBMDs commonly become infected with bacterial biofilms leading to medical device failure, infection, and adverse patient outcomes. Introduction. Histotripsy is a noninvasive focused ultrasound ablation method that was recently proposed as a novel method to remove intraluminal biofilms. Here, we explore the potential of combining histotripsy with acoustically active particles to develop a PMH approach that can noninvasively remove biofilms without the need for high acoustic pressures or real-time image guidance for targeting. Methods. Histotripsy cavitation thresholds in catheters containing either gas-filled microbubbles (MBs) or fluid-filled nanocones (NCs) were determined. The ability of these particles to sustain cavitation over multiple ultrasound pulses was tested after a series of histotripsy exposures. Next, the ability of PMH to generate selective intraluminal cavitation without generating extraluminal cavitation was tested. Finally, the biofilm ablation and bactericidal capabilities of PMH were tested using both MBs and NCs. Results. PMH significantly reduced the histotripsy cavitation threshold, allowing for selective luminal cavitation for both MBs and NCs. Results further showed PMH successfully removed intraluminal biofilms in Tygon catheters. Finally, results from bactericidal experiments showed minimal reduction in bacteria viability. Conclusion. The results of this study demonstrate the potential for PMH to provide a new modality for removing bacterial biofilms from CBMDs and suggest that additional work is warranted to develop histotripsy and PMH for treatment of CBMD intraluminal biofilms.

Burden of bacterial bloodstream infections and recent advances for diagnosis

Bloodstream infections (BSIs) and subsequent organ dysfunction (sepsis and septic shock) are conditions that rank among the top reasons for human mortality and have a great impact on healthcare systems. Their treatment mainly relies on the administration of broad-spectrum antimicrobials since the standard blood culture-based diagnostic methods remain time-consuming for the pathogen's identification. Consequently, the routine use of these antibiotics may lead to downstream antimicrobial resistance and failure in treatment outcomes. Recently, significant advances have been made in improving several methodologies for the identification of pathogens directly in whole blood especially regarding specificity and time to detection. Nevertheless, for the widespread implementation of these novel methods in healthcare facilities, further improvements are still needed concerning the sensitivity and cost-effectiveness to allow a faster and more appropriate antimicrobial therapy. This review is focused on the problem of BSIs and sepsis addressing several aspects like their origin, challenges, and causative agents. Also, it highlights current and emerging diagnostics technologies, discussing their strengths and weaknesses.

Cutaneous Microbiome Profiles Following Chlorhexidine Treatment in a 72-Hour Daily Follow-Up Paired Design: a Pilot Study

Venous catheter-related bloodstream infections represent a significant problem in the United States. Our objective was to determine daily changes in skin microbiome profiles up to 72h postchlorhexidine treatment. Left and right forearm skin swab samples were obtained from 10 healthy volunteers over 72h at 24h intervals. Dorsal surface of left arm was treated with chlorohexidine gluconate (CHG) at initial time point (T = 0), while the right arm remained untreated (control). Swab samples were obtained shortly before (T = 0) and after CHG treatment (T = 24-48-72h). Bacterial DNA extraction, 16S rRNA gene V1-V3 sequencing and taxonomic annotation were performed using ZymoBIOMICS pipeline. PERMANOVA, linear discriminant and bacterial interaction network analyses were performed. A total of 13 total phyla, 273 genera, and 950 total species were detected across all time points, CHG-treated or CHG-untreated. Most abundant species included Cutibacterium acnes, Staphylococcus epidermidis, and Rothia Mucilaginosa. Low biomass-related inconsistent taxa detection was observed. PERMANOVA suggested a marginal difference between CHG-treated and CHG-untreated microbiome profiles (Genera: P(perm) = 0.0531; Species: P(perm) = 0.0450). Bacterial interaction network guided PERMANOVA analyses detected a microbiome change over time, suggesting a consistent CHG treatment-specific change. LEfSe identified Finegoldia magna, Bacillus pumilus, Bacillus thermoamylovorans as the only distinctive species. These species were more abundant and/or present post-CHG treatment in the CHG-treated group. These findings suggest that the skin microbiome was not significantly different 24, 48, or 72h after CHG treatment. Previous culture-based studies have found similar results after 24h. Future studies will be needed to determine the mechanisms of bacterial regrowth after CHG treatment. IMPORTANCE Annually, over 80,000 central line infections occur in the United States. Understanding the pathogenesis of these infections is crucial. Chlorhexidine is the most commonly used skin preparation before line placement. We hypothesized that the use of chlorhexidine and dressings will alter the normal arm skin microbiome over a period of 72h. We used 16S-rRNA gene next generation sequencing (NGS) to determine the forearm skin microbiome of volunteers. The left arm was swabbed with chlorhexidine and the right arm served as control. The skin microbiome returned to normal after 24h. Our NGS results confirm findings of two previous culture-based studies. Relative abundance of Bacillus spp. in the chlorhexidine-treated samples was increased, consistent with one previous study. Based on the results of this pilot study, we will need to measure viable bacteria during a 24h time course following chlorhexidine treatment to understand the source of skin microbiome replenishment.

Nitric Oxide-Releasing Lock Solution for the Prevention of Catheter-Related Infection and Thrombosis

Although frequently used, venous catheters are often associated with serious complications such as infection and thrombosis. Lock solution therapies are clinically used to deter these issues but generally address only infection or thrombosis with limited success. Here, we report the development of a dual-functional lock therapy using nitric oxide (NO) donor molecule, S-nitrosoglutathione (GSNO). NO is a potent, broad-spectrum antimicrobial agent that also temporarily inhibits platelet activation, preventing thrombosis. Furthermore, NO has antibiofilm actions, an ability that traditional antibiotic lock solutions lack, thus limiting their efficacy. In this work, different concentrations of GSNO were characterized via NO analysis to determine a range of NO-releasing lock solution (NOreLS) concentrations to investigate and to demonstrate prolonged potential efficacy. Tested against clinically used vancomycin and gentamicin lock solutions, GSNO-based NOreLS repeatedly outperformed in models of different stages of catheter infections. NOreLS also prevented clot formation when exposed to whole blood, showing increased efficacy compared to a heparin lock solution. Moreover, NOreLS was demonstrated to be biocompatible via hemolysis and cytotoxicity assays. NOreLS has excellent potential for safely and effectively preventing infection and thrombosis related to catheter usage.

Transparent and Highly Flexible Hierarchically Structured Polydimethylsiloxane Surfaces Suppress Bacterial Attachment and Thrombosis Under Static and Dynamic Conditions

The surface fouling of biomedical devices has been an ongoing issue in healthcare. Bacterial and blood adhesion in particular, severely impede the performance of such tools, leading to poor patient outcomes. Various structural and chemical modifications have been shown to reduce fouling, but all existing strategies lack the combination of physical, chemical, and economic traits necessary for widespread use. Herein, a lubricant infused, hierarchically micro- and nanostructured polydimethylsiloxane surface is presented. The surface is easy to produce and exhibits the high flexibility and optical transparency necessary for incorporation into various biomedical tools. Tests involving two clinically relevant, priority pathogens show up to a 98.5% reduction in the biofilm formation of methicillin-resistant Staphylococcus aureus and Pseudomonas aeruginosa. With blood, the surface reduces staining by 95% and suppresses thrombin generation to background levels. Furthermore, the surface shows applicability within applications such as catheters, extracorporeal circuits, and microfluidic devices, through its effectiveness in dynamic conditions. The perfusion of bacterial media shows up to 96.5% reduction in bacterial adhesion. Similarly, a 95.8% reduction in fibrin networks is observed following whole blood perfusion. This substrate stands to hold high applicability within biomedical systems as a means to prevent fouling, thus improving performance.

All-cause mortality and disease progression in SARS-CoV-2-infected patients with or without antibiotic therapy: an analysis of the LEOSS cohort

PURPOSE

Reported antibiotic use in coronavirus disease 2019 (COVID-19) is far higher than the actual rate of reported bacterial co- and superinfection. A better understanding of antibiotic therapy in COVID-19 is necessary.

METHODS

6457 SARS-CoV-2-infected cases, documented from March 18, 2020, until February 16, 2021, in the LEOSS cohort were analyzed. As primary endpoint, the correlation between any antibiotic treatment and all-cause mortality/progression to the next more advanced phase of disease was calculated for adult patients in the complicated phase of disease and procalcitonin (PCT) ≤ 0.5 ng/ml. The analysis took the confounders gender, age, and comorbidities into account.

RESULTS

Three thousand, six hundred twenty-seven cases matched all inclusion criteria for analyses. For the primary endpoint, antibiotic treatment was not correlated with lower all-cause mortality or progression to the next more advanced (critical) phase (n = 996) (both p > 0.05). For the secondary endpoints, patients in the uncomplicated phase (n = 1195), regardless of PCT level, had no lower all-cause mortality and did not progress less to the next more advanced (complicated) phase when treated with antibiotics (p > 0.05). Patients in the complicated phase with PCT > 0.5 ng/ml and antibiotic treatment (n = 286) had a significantly increased all-cause mortality (p = 0.029) but no significantly different probability of progression to the critical phase (p > 0.05).

CONCLUSION

In this cohort, antibiotics in SARS-CoV-2-infected patients were not associated with positive effects on all-cause mortality or disease progression. Additional studies are needed. Advice of local antibiotic stewardship- (ABS-) teams and local educational campaigns should be sought to improve rational antibiotic use in COVID-19 patients.

Current Guidelines and Practice Recommendations to Prevent Hospital-Acquired Conditions After Major Orthopaedic Surgeries

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In 2016, a total of 48,771 hospital-acquired conditions (HACs) were reported in U.S. hospitals. These incidents resulted in an excess cost of >$2 billion, which translates to roughly $40,000 per patient with an HAC.

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Current guidelines for the prevention of venous thromboembolism and surgical site infection consist primarily of antithrombotic prophylaxis and antiseptic technique, respectively.

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The prevention of catheter-associated urinary tract infection (CA-UTI) and in-hospital falls and trauma is done best via education. In the case of CA-UTI, this consists of training staff about the indications for catheters and their timely removal when they are no longer necessary, and in the case of in-hospital falls and trauma, advising the patient and family about the patient's fall risk and communicating the fall risk to the health-care team.

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Blood incompatibility is best prevented by implementation of a pretransfusion testing protocol. Pressure ulcers can be prevented via patient positioning, especially during surgery, and via postoperative skin checks.

Central venous catheters are associated with thrombosis among adult inpatients undergoing therapeutic plasma exchange

BACKGROUND

For inpatients undergoing therapeutic plasma exchange (TPE) in the United States, the primary mode of venous access is the central venous catheter (CVC). To evaluate the impact of CVC on thrombosis outcomes of patients undergoing TPE, we analyzed the National Inpatient Sample (NIS) database.

STUDY DESIGN AND METHODS

In a cross-sectional analysis of the NIS, we identified hospital discharges of adult patients treated with TPE. Cases were classified into two groups based on CVC status. The primary outcome was thrombosis. Secondary outcomes were major bleeding, packed red blood cell (PRBC) transfusion, in-hospital mortality, hospital length of stay (LOS), and charges.

RESULTS

Among 9863 TPE-treated discharges, CVC was used in 5988 (60%). These numbers correspond to weighted national estimates of 49 315 and 29 940, respectively. There was a positive and significant association between CVC and thrombosis (OR = 1.23, 95% 1.04-1.46, P = 0.0174), PRBC transfusion (OR = 1.15, 95% 1.03-1.29, P = 0.0121), in-hospital mortality (OR = 1.36, 95% 1.10-1.68, P = 0.0043), hospital LOS (15.63 vs 12.45 days, P < 0.0001) and hospital charges ($166 387 vs. $132 655, P < 0.0001).

CONCLUSION

In hospitalized patients undergoing TPE, CVC use is associated with increased rates of thrombosis. Future studies are needed to investigate strategies to decrease CVC use and/or prevent CVC-associated complications in TPE-treated inpatients.

Is it safe and efficacious to remove central lines in pediatric bone marrow transplant patients with platelets less than 20,000/μl?

Background

Patients with tunneled central venous lines (CVL) may develop bloodstream infections which at times are difficult to control without line removal. Concomitant severe thrombocytopenia with platelet transfusion refractoriness is often considered a major contraindication to any procedure involving a major blood vessel. There is very little literature on the clinical risks of tunneled central line removal in febrile pancytopenia patients.

Procedure

We analyzed complications and outcomes in all our patients, a total of 52, who underwent CVL removal with platelets <20,000/μl.

Results

CVL removal was done on a median day of 17.5 with 47 of the 52 patients never having achieved platelets engraftment prior to line removal. No bleeding episodes or unplanned transfusions could be associated with CVL removal. No other complications were also reported. All patients had time to hemostasis within 5 min of catheter removal. Removal of CVL under local anesthesia remained complication-free even at platelet counts less than 20,000/ul. A total of 31 patients were febrile at the time of CVL removal, of which 17 became afebrile within 2 days. We found no difference in defervescence when comparing those whose antibiotic therapy was changed/escalated versus those in whom it was not.

Conclusion

Our findings suggest that central lines can be safely removed with platelet counts less than 20,000/ul and that this may result in enhanced bloodstream infection control. This might be particularly relevant to neutropenic patients in this day and age of multidrug-resistant organism emergence and paucity of new effective antibiotics.

Vascular Access in Therapeutic Apheresis: One Size Does not Fit All

BACKGROUND

Therapeutic apheresis has been used in treating hematological and non-hematological diseases. For a successful procedure, efficient vascular access is required. Presently, peripheral venous access (PVA), central venous catheterization (CVC), implantable ports, and arteriovenous fistulas (AVFs) are used. This review aims to evaluate different type of access and their pros and cons to help physicians determine the best venous access.

METHODS

The electronic search included PubMed and Google Scholar up to Nov. 2020. The Mesh terms were apheresis, peripheral catheterization, central catheterization, and arteriovenous fistula.

RESULTS

A total of 228 studies were found through database searching. Two independent authors reviewed the articles using their titles and abstracts; 88 articles were selected and the full text was reviewed. Finally, 25 were included. The inclusion criteria were studies incorporating patients with any indication for apheresis.

CONCLUSION

PVA has been promoted in recent years in many centers across the United States to lower the rate of complications associated with vascular access and to make this procedure more accessible. Several factors are involved in selecting appropriate venous access, such as the procedure's duration and frequency, patient's vascular anatomy, and staff's experience. In short-term procedures, temporary vascular access like PVA or CVC is preferred. Permanent vascular access such as AVF, tunneled cuffed central lines, and implantable ports are more beneficial in prolonged treatment period but each patient has to be evaluated individually by apheresis team for the most appropriate method.

Index for the appropriate vancomycin dosing in premature neonates and infants

BACKGROUND

In neonates, vancomycin (VCM) is used to treat Gram-positive bacterial infections. However, VCM blood concentrations are affected by gestational age, bodyweight (BW), and renal function. The initial VCM dose adjustment can therefore be difficult, and few reports have evaluated this issue. In this study, we investigated the factors determining the appropriate VCM dosing schedule in neonates, especially premature infants.

METHODS

The VCM dosage and trough concentrations were retrospectively investigated from the initial treatment to maintenance therapy in neonatal intensive care unit patients who underwent therapeutic drug monitoring. We examined the average single-administration VCM dosage during maintenance therapy. We then compared the actual VCM dose with that calculated using an index comprising six items that influence the VCM daily dose (postnatal age, gestational age, BW, serum creatinine level, urine output, and lactate level).

RESULTS

Twenty premature infants were included. The average BW of patients at the initial VCM administration was 975 g. During maintenance therapy, the average VCM dose was 8.4 mg/kg, and the median trough concentration was 12.4 μg/mL. When we applied the six-item index, 18 of 20 patients (90%) had concordant results between the actual VCM dosing schedule and the VCM calculated using the index.

CONCLUSIONS

The average VCM dose and six-item index can facilitate the transition from the initial VCM dose to an appropriate dose in many cases and contribute to early treatment in low-birthweight infants with more variable BW, distribution volumes, and renal function. In conclusion, our six-item index may help standardize VCM administration in premature infants.

Treatment of MRSA infections in India: Clinical insights from a Delphi analysis

PURPOSE

International and Indian guidelines for the management of patients with methicillin-resistant Staphylococcus aureus (MRSA) infections are available, but the local guidelines are not MRSA-specific. This study aimed to provide clinical insights for the treatment of MRSA infections in India.

METHODS

We used a three-step modified Delphi method to obtain insights. Ten experts comprising infectious disease specialists, microbiologists, pulmonologists, and critical care experts agreed to participate in the analysis. In round 1, a total of 161 statements were circulated to the panel and the experts were asked to 'agree' or 'disagree' by responding 'yes' or 'no' to each statement and provide comments. The same process was used for 73 statements in round 2. Direct interaction with the experts was carried out in round 3 wherein 35 statements were discussed. At least 80% of the experts had to agree for a statement to reach concordance.

RESULTS

Eighty-eight statements in round 1, thirty-eight statements in round 2, and eight statements in round 3 reached concordance and were accepted without modification. The final document comprised 152 statements on the management of various syndromes associated with MRSA such as skin and soft tissue infections, bacteremia and endocarditis, pneumonia, bone and joint infections, and central nervous system infections.

CONCLUSIONS

This analysis will assist clinicians in India to choose an appropriate course of action for MRSA infections.

Duration of antibiotic therapy in central venous catheter-related bloodstream infection due to Gram-negative bacilli

PURPOSE OF REVIEW

The aim of this study was to review recent data evaluating the duration of antibiotic therapy in central venous catheter-related bloodstream infection (CRBSI) due to Gram-negative bacilli (GNB).

RECENT FINDINGS

CRBSI is the most common complication associated with the use of intravascular catheters. CRBSI directly contributes to increase additional days of hospitalization, morbidity and therefore economic costs.The incidence of GNB CRBSI has been increasing considerably in the last years; this has raised a concern due to the high reported rate of multi drug resistant bacteria in these infections what poses a considerable challenge for effective treatment. However, there are no specific guidelines for management of GNB-CRBSI and optimal treatment duration has not been clearly defined.Recent studies evaluating the impact of the duration of antibiotic therapy of GNB-CRBSI have shown that short-course antibiotic therapy might be as effective as long-course therapy once the central venous catheter (CVC) has been removed.

SUMMARY

CRBSI due to GNB has shown a rapid increase in the last years. Current guidelines recommend antibiotic treatment for at least 7-14 days, although no randomized clinical trials have evaluated the optimal duration of antibiotic therapy for GNB-CRBSI. Recent data suggest that administration of appropriate antibiotic therapy for 7 days or less may be as well tolerated and effective as longer courses in episodes of GNB-CRBSI, once the CVC has been removed.

Evaluation of a Murine Model for Testing Antimicrobial Implant Materials in the Blood Circulation System

Medical device-related infections are becoming a steadily increasing challenge for the health care system regarding the difficulties in the clinical treatment. In particular, cardiovascular implant infections, catheter-related infections, as well as infective endocarditis are associated with high morbidity and mortality risks for the patients. Antimicrobial materials may help to prevent medical device-associated infections and supplement the currently available therapies. In this study, we present an easy-to-handle and simplified in vivo model to test antimicrobial materials in the bloodstream of mice. The model system is composed of the implantation of a bacteria-laden micro-stent scaffold into the murine tail vein. Our model enables the simulation of catheter-related infections as well as the development of infective endocarditis specific pathologies in combination with material testing. Furthermore, this in vivo model can cover two phases of the biofilm formation, including both the local tissue response to the bacterial biofilm and the systemic inflammatory response against circulating bacteria in the bloodstream that detached from a mature biofilm.

Microbial Repercussion on Hemodialysis Catheter-Related Bloodstream Infection Outcome: A 2-Year Retrospective Study

Background

Albeit growing technical advances in the design of hemodialysis catheters, intravascular catheter-related bloodstream infection (CRBSI) still represents an utmost clinical challenge to the health-care workers (HCWs). Data regarding the influence of the culprit organism on the scenario of CRBSI in the literature are extremely lacking. Thereby, this research was carried out.

Methods

We undertook a retrospective cohort study over an interval of 2 years, involving patients who underwent regular hemodialysis via catheters in the Renal Dialysis Unit (RDU) of Dr. Soliman Fakeeh Hospital (DSFH), Jeddah, Kingdom of Saudi Arabia (KSA). The study enrolled 139 patients (56.8% females and 43.2% males), with mean age of 60.79 ± 11.45 years.

Results

The aggregate rate of CRBSI was 5.1/1000 catheter days. Amongst the 139 study candidates confirmed of having CRBSI, while 69.8% of CRBSIs were ascribed to Gram-positive cocci, about one-third of the infectious episodes were secondary to Gram-negative bacilli. Interestingly, fever was the most common presentation of S. aureus CRBSI compared to CoNS and Gram-negative bacilli CRBSIs (20.9% versus 12.9% versus 6.5%, p= 0.0001), whereas CRBSIs due to CoNS were presented mainly with rigors (19.4%). Of note, CRBSIs caused by Gram-negative bacilli had a tendency to manifest with unusual symptoms such as vomiting or hypotension. Besides, they were more prone to involve hospitalization or ICU admission. In this study, no mortality was attributed to CRBSIs.

Conclusion

Our study disclosed that the illicit organism has a repercussion on the clinical presentation as well as the fate of CRBSI among hemodialysis patients. This highlights the worth of identifying the infected cases in a periodic manner, to avoid the occurrence of devastating complications. A large body of work from various hemodialysis centers should take place in the near future so as to provide more insight in this perspective.

Trends of central line-associated bloodstream infections in the intensive care unit in the Kingdom of Bahrain: Four years’ experience

BACKGROUND

The central venous line is an essential component in monitoring and managing critically ill patients. However, it poses patients with increased risks of severe infections with a higher probability of morbidity and mortality.

AIM

To define the trends of the rates of central line-associated bloodstream infections (CLABSI) over four years, its predicted risk factors, aetiology, and the antimicrobial susceptibility of the isolated pathogens.

METHODS

The study was a prospective case-control study, performed according to the guidelines of the Center for Disease Control surveillance methodology for CLABSI in patients admitted to the adult intensive care unit (ICU) and auditing the implementation of its prevention bundle.

RESULTS

Thirty-four CLABSI identified over the study period, giving an average CLABSI rate of 3.2/1000 central line days. The infection's time trend displayed significant reductions over time concomitantly with the CLABSI prevention bundle's reinforcement from 4.7/1000 central line days at the beginning of 2016 to 1.4/1000 central line days by 2018. The most frequently identified pathogens causing CLABSI in our ICU were gram-negative organisms (59%). The most common offending organisms were Acinetobacter, Enterococcus, and Staphylococcus epidermidis, each of them accounted for 5 cases (15%). Multidrug-resistant organisms contributed to 56% of CLABSI. Its rate was higher when using femoral access and longer hospitalisation duration, especially in the ICU. Insertion of the central line in the non-ICU setting was another identified risk factor.

CONCLUSION

Implementing the prevention bundles reduced CLABSI significantly in our ICU. Implementing the CLABSI prevention bundle is crucial to maintain a substantial reduction in the CLABSI rate in the ICU setting.

Fighting S. aureus catheter-related infections with sophorolipids: Electing an antiadhesive strategy or a release one?

Staphylococcus aureus medical devices related-infections, such as blood stream catheter are of major concern. Their prevention is compulsory and strategies, not prone to the development of resistance, to prevent S. aureus biofilms on catheter surfaces (e.g. silicone) are needed. In this work two different approaches using sophorolipids were studied to prevent S. aureus biofilm formation on medical grade silicone: i) an antiadhesive strategy through covalent bond of sophorolipids to the surface; ii) and a release strategy using isolated most active sophorolipids. Sophorolipids produced by Starmerella bombicola, were characterized by UHPLC-MS and RMN, purified by automatic flash chromatography and tested for their antimicrobial activity towards S. aureus. Highest antimicrobial activity was observed for C18:0 and C18:1 diacetylated lactonic sophorolipids showing a MIC of 50 μg mL^-1. Surface modification with acidic or lactonic sophorolipids when evaluating the anti-adhesive or release strategy, respectively, was confirmed by contact angle, FTIR-ATR and AFM analysis. When using a mixture of acidic sophorolipids covalently bonded to silicone surface as antiadhesive strategy cytocompatible surfaces were obtained and a reduction of 90 % on biofilm formation was observed. Nevertheless, if a release strategy is adopted with purified lactonic sophorolipids a higher effect is achieved. Most promising compound was C18:1 diacateylated lactonic sophorolipid that showed no cellular viability reduction when a concentration of 1.5 mg mL^-1 was selected and a reduction on biofilm around 5 log units. Results reinforce the applicability of these antimicrobial biosurfactants on preventing biofilms and disclose that their antimicrobial effect is imperative when comparing to their antiadhesive properties.

Biofilm and catheter-related bloodstream infections

Careful attention to detail and adherence to procedure guidelines when inserting and managing intravascular catheters has decreased the incidence of catheter-related bloodstream infections (CRBSIs). In order to limit these, health professionals must understand the underlying microbiology. Biofilms can explain the clinical findings most often seen with CRBSIs, yet they are poorly understood within medicine. Bacteria growing on solid surfaces such as a catheter are predominantly in biofilm phenotype, with a group of genes active that allow the bacteria to be tolerant to antiseptics and antibiotics by producing a self-secreted protective matrix. It is unclear whether it is planktonic seeding or small fragments of biofilm breaking off into the bloodstream that eventually results in the acute infection. The literature identifies four routes for microbes to adhere to a catheter and start biofilm formation: catheter contact, catheter insertion, catheter management and non-catheter-related sources. Routine clinical culture methods are inadequate to fully identify microbes producing catheter biofilm and/or bloodstream infection, therefore DNA methods may be required to diagnose CRBSIs. Treatment is removal and reinsertion of the catheter in a different site when possible. However, antibiofilm strategies can be employed to try to salvage the catheter. The use of high-dose antiseptics or antibiotics for long durations inside the catheter and hub (antibiotic/antiseptic lock) can suppress biofilm enough to reduce the seeding of the blood below a level where the patient's immune system can prevent bloodstream infection.

Environmentally friendly antibiofilm strategy based on cationized phytoglycogen nanoparticles

Biofilm tolerance to antibiotics has led to the search for new alternatives in treating biofilms. The use of metallic nanoparticles has been a suggested strategy against biofilms, but their potential environmental toxicity and high cost of synthesizing have limited their applications. In this study, we investigate the potential of polysaccharidic phytoglycogen nanoparticles extracted from corn, in treating cyanobacterial biofilms, which are the source of toxins and pollution in aquatic environments. Our results revealed that the surface of cyanobacterial cells was dominated by the negatively charged functional groups such as carboxylic and phosphoric groups. The native phytoglycogen (PhX) nanoparticles were dominated with non-charged groups, such as hydroxyl groups, and the cationized phytoglycogen (PhXC) nanoparticles showed positively charged surfaces due to the presence of quaternary ammonium cations. Our results indicated that, as opposed to PhX, PhXC strongly inhibited biofilm formation when dispersed in the culture medium. PhXC also eradicated the already grown cyanobacterial biofilms. The antibiofilm properties of PhXC were attributed to its strong electrostatic interactions with the cyanobacterial cells, which could inhibit cell/cell and cell/substrate interactions and nutrient exchange with the media. This class of antibacterial polysaccharide nanoparticles may provide a novel cost-effective and environment-friendly strategy for treating biofilm formation by a broad spectrum of bacteria.

Retrospective Study of Nosocomial Infections in the Orthopaedic and Rehabilitation Clinic of the Medical University of Lublin in the Years 2018-2020

Nosocomial infections appear in patients treated in hospital, which are not the initial cause of admission. A retrospective study concerning nosocomial infections was conducted to provide data about the amount, frequency and types of nosocomial infections in the rehabilitation ward in the Orthopaedics and Rehabilitation Clinic of Lublin. The study was conducted on a group of 49 patients that were admitted or transferred to the ward over a period of 20 months in the years 2018–2020. The patients and therefore the infections were divided by age, sex, time of hospitalization and the underlying disease. The study also provided data about the most frequent infection types in these patients, as well as the most commonly used drugs to treat those infections. The results showed that in fact all of the examined factors have an impact on the frequency of nosocomial infections appearance rates. Furthermore, results in the study showed that factors examined by the study also have an impact on what type of infection was present in these groups of patients.

Prevalence and Impact of Biofilms on Bloodstream and Urinary Tract Infections: A Systematic Review and Meta-Analysis

This study sought to assess the prevalence and impact of biofilms on two commonly biofilm-related infections, bloodstream and urinary tract infections (BSI and UTI). Separated systematic reviews and meta-analyses of observational studies were carried out in PubMed and Web of Sciences databases from January 2005 to May 2020, following PRISMA protocols. Studies were selected according to specific and defined inclusion/exclusion criteria. The obtained outcomes were grouped into biofilm production (BFP) prevalence, BFP in resistant vs. susceptible strains, persistent vs. non-persistent BSI, survivor vs. non-survivor patients with BSI, and catheter-associated UTI (CAUTI) vs. non-CAUTI. Single-arm and two-arm analyses were conducted for data analysis. In vitro BFP in BSI was highly related to resistant strains (odds ratio-OR: 2.68; 95% confidence intervals-CI: 1.60–4.47; p < 0.01), especially for methicillin-resistant Staphylococci. BFP was also highly linked to BSI persistence (OR: 2.65; 95% CI: 1.28–5.48; p < 0.01) and even to mortality (OR: 2.05; 95% CI: 1.53–2.74; p < 0.01). Candida spp. was the microorganism group where the highest associations were observed. Biofilms seem to impact Candida BSI independently from clinical differences, including treatment interventions. Regarding UTI, multi-drug resistant and extended-spectrum β-lactamase-producing strains of Escherichia coli, were linked to a great BFP prevalence (OR: 2.92; 95% CI: 1.30–6.54; p < 0.01 and OR: 2.80; 95% CI: 1.33–5.86; p < 0.01). More in vitro BFP was shown in CAUTI compared to non-CAUTI, but with less statistical confidence (OR: 2.61; 95% CI: 0.67–10.17; p < 0.17). This study highlights that biofilms must be recognized as a BSI and UTI resistance factor as well as a BSI virulence factor.

Catheter-related bloodstream infections: predictive factors for Gram-negative bacteria aetiology and 30 day mortality in a multicentre prospective cohort

BACKGROUND

Catheter-related bloodstream infections (CRBSIs) increase morbidity and mortality, prolong hospitalization and generate considerable medical costs. Recent guidelines for CRBSI recommend empirical therapy against Gram-positive bacteria (GPB) and restrict coverage for Gram-negative bacteria (GNB) only to specific circumstances.

OBJECTIVES

To investigate predictors of GNB aetiology in CRBSI and to assess the predictors of outcome in patients with CRBSI.

METHODS

Patients with CRBSI were selected from the PROBAC cohort, a prospective, observational, multicentre national cohort study including patients with bloodstream infections consecutively admitted to 26 Spanish hospitals in a 6 month period (October 2016-March 2017). Outcome variables were GNB aetiology and 30 day mortality. Adjusted analyses were performed by logistic regression.

RESULTS

Six hundred and thirty-one episodes of CRBSI were included in the study. Risk factors independently related to GNB aetiology were central venous catheter (CVC) [OR 1.60 (95% CI: 1.05-2.44), P = 0.028], sepsis/septic shock [OR: 1.76 (95% CI: 1.11-2.80), P = 0.016], antibiotic therapy in the previous 30 days [OR: 1.56 (95% CI: 1.02-2.36), P = 0.037], neutropenia <500/μL [OR: 2.01 (95% CI: 1.04-3.87), P = 0.037] and peripheral vascular disease [OR: 2.04 (95% CI: 1.13-3.68), P = 0.018]. GNB were not associated with increased mortality in adjusted analysis, while removal of catheter [OR: 0.24 (95% CI: 0.09-0.61), P = 0.002] and adequate empirical treatment [OR: 0.37 (95% CI: 0.18-0.77), P = 0.008] were strong protective factors.

CONCLUSIONS

Our study reinforces the recommendation that empirical coverage should cover GNB in patients presenting with sepsis/septic shock and in neutropenic patients. Catheter removal and adequate empirical treatment were both protective factors against mortality in patients with CRBSI.

Determinants of neonatal sepsis among neonates delivered in Southwest Ethiopia 2018: A case-control study

INTRODUCTION

Neonatal sepsis is one of the principal causes of neonatal morbidity and mortality. In spite of interventions with different preventive methods, the burden of neonatal sepsis is being reported in different parts of Ethiopia. For further interventions, identifying its determinants is found to be essential.

OBJECTIVE

The study aimed to assess the determinants of neonatal sepsis among neonates delivered in Southwest Ethiopia in 2018.

METHODS

A hospital-based case-control study was conducted in Southwest Ethiopia from May 2018 to August 2018. Systematic random sampling technique was used to select study participants; Cases were neonates diagnosed with sepsis and controls were neonates without sepsis. Data were entered into Epi info version 7.2 and analyzed using Statistical Package for Social Sciences version 23. Bi-variable logistic regression was used to identify determinants of neonatal sepsis and those variables with a p-value < 0.05 in the multivariable logistic regression analysis were considered as significantly associated at a 95% confidence interval.

RESULTS

The findings from the multivariable logistic regression revealed that history of meconium-stained amniotic fluid (adjusted odds ratio [95% confidence interval] = 9.2 [1.1, 19.8]), history of foul-smelling liquor (adjusted odds ratio [95% confidence interval] = 5.2 [1.2, 22.3]), history of maternal sexually transmitted infection/urinary tract infection (adjusted odds ratio [95% confidence interval[ = 4.7 [1.1, 19.7]), history of vascular catheter (adjusted odds ratio [95% confidence interval] = 4.7 [1.11, 20]), and low birth weight (adjusted odds ratio [95% confidence interval] = 5.3 [1.3, 28.9]) were identified as determinants of neonatal sepsis.

CONCLUSION

Generally, history of meconium-stained amniotic fluid, foul-smelling liquor, maternal history of the sexually transmitted disease, urinary tract infection, low birth weight, and the vascular catheter was identified as determinants of neonatal sepsis. Health education should be provided for pregnant mothers regarding health care-seeking behavior. Similarly, diagnoses and care should be accessible on time for foul-smelling liquor, premature rupture of membrane, and low birth weight.

Staphylococcus epidermidis Has Growth Phase Dependent Affinity for Fibrinogen and Resulting Fibrin Clot Elasticity

Bacterial infection and thrombosis are highly correlated, especially in patients with indwelling medical devices. Coagulase-negative staphylococci, typified by Staphylococcus epidermidis, are a common cause of medical device infections owing to their biofilm forming capacity which provides protection from antibiotics and host immune response. Attention has been drawn to the interaction between S. epidermidis and host proteins, specifically fibrinogen. However, little is known regarding the impact of the transition from planktonic to biofilm forming phenotype on this interaction. Here we investigate the growth phase dependence of bacteria-fibrinogen interaction and the resulting effect on fibrin clot formation, structure, and mechanics. Flow cytometry demonstrated growth phase dependent affinity for fibrinogen. To mimic intravascular device seeding, we quantified the adhesion of S. epidermidis to a fibrinogen coated surface under continuous flow conditions in vitro. The bacterial deposition rate onto fibrinogen was significantly greater for stationary (5,360 ± 1,776 cells/cm²s) versus exponential phase (2,212 ± 264, cells/cm² s). Furthermore, the expression of sdrG–a cell surface adhesion protein with specificity for fibrinogen–was upregulated ∼twofold in the stationary versus the exponential phase. Rheometry and confocal microscopy demonstrated that stationary phase S. epidermidis slows clot formation and generates a more heterogeneous fibrin network structure with greater elasticity (G′ = 5.7 ± 1.0 Pa) compared to sterile fibrinogen (G′ = l.5 ± 0.2 Pa), while exponential phase cells had little effect. This work contributes to the current understanding of the growth phase dependent regulation of bacterial virulence factors and the correlation between bacterial infection and thrombosis.

Safety and efficacy of anticoagulant therapy in pediatric catheter-related venous thrombosis (EINSTEIN-Jr CVC-VTE)

Anticoagulant treatment of pediatric central venous catheter-related venous thromboembolism (CVC-VTE) has not been specifically evaluated. In EINSTEIN-Jr, 500 children with any VTE received rivaroxaban or standard anticoagulants. A predefined analysis of the CVC-VTE cohort was performed. Children with CVC-VTE (age, birth to 17 years) were administered rivaroxaban or standard anticoagulants during the 1-month (children <2 years) or 3-month (all other children) study period. Predefined outcomes were recurrent VTE, change in thrombotic burden on repeat imaging, and bleeding. Predictors for continuation of anticoagulant therapy beyond the study period were evaluated. One hundred twenty-six children with symptomatic (n = 76, 60%) or asymptomatic (n = 50, 40%) CVC-VTE received either rivaroxaban (n = 90) or standard anticoagulants (n = 36). There was no recurrent VTE (0%; 95% confidence interval [CI], 0.0%-2.8%). Three children had the principal safety outcome: none had major bleeding and 3 children had clinically relevant nonmajor bleeding (2.4%; 95% CI, 0.7%-6.5%), all in the rivaroxaban arm. Complete or partial vein recanalization occurred in 57 (55%) and 38 (37%) of 103 evaluable children, respectively. Results were similar for symptomatic and asymptomatic CVC-VTE. Continuation of anticoagulant therapy beyond the study period occurred in 61 (48%) of children and was associated with residual VTE but only in children <2 years (odds ratio [OR], 20.9; P = .003) and continued CVC use (OR, 6.7; P = .002). Anticoagulant therapy appeared safe and efficacious and was associated with reduced clot burden in most children with symptomatic or asymptomatic CVC-VTE. Residual VTE and continued CVC use were associated with extended anticoagulation. This trial was registered at www.clinicaltrials.gov as #NCT02234843.