Positive Catheter Tip Cultures Research Articles

Treatment of positive catheter tip culture without bloodstream infections in critically ill patients. A case-cohort study from the OUTCOMEREA network

PurposeThis study aimed to evaluate the impact on subsequent infections and mortality of an adequate antimicrobial therapy within 48 h after catheter removal in intensive care unit (ICU) patients with positive catheter tip culture.MethodsWe performed a retrospective analysis of prospectively collected data from 29 centers of the OUTCOMEREA network. We developed a propensity score (PS) for adequate antimicrobial treatment, based on expert opinion of 45 attending physicians. We conducted a 1:1 case-cohort study matched on the PS score of being adequately treated. A PS-matched subdistribution hazard model was used for detecting subsequent infections and a PS-matched Cox model was used to evaluate the impact of antibiotic therapy on mortality.ResultsWe included 427 patients with a catheter tip culture positive with potentially pathogenic microorganisms. We matched 150 patients with an adequate antimicrobial therapy with 150 controls. In the matched population, 30 (10%) subsequent infections were observed and 62 patients died within 30 days. Using subdistribution hazard models, the daily risk to develop subsequent infection up to Day-30 was similar between treated and non-treated groups (subdistribution hazard ratio [sHR] 1.08, 95% confidence interval [CI] 0.62–1.89, p = 0.78). Using Cox proportional hazard models, the 30-day mortality risk was similar between treated and non-treated groups (HR 0.89, 95% CI 0.45–1.74, p = 0.73).ConclusionsAntimicrobial therapy was not associated with decreased risk of subsequent infection or death in short-term catheter tip colonization in critically ill patients. Antibiotics may be unnecessary for positive catheter tip cultures.

Clinical Outcome of Patients with Escherichia coli Isolated from Catheter Lumens and/or Peripheral Blood Cultures: A Retrospective Analysis.

Escherichia coli commonly causes catheter-related bloodstream infection (C-RBSI) in specific populations. The differential time to positivity (DTTP) technique is the recommended conservative procedure for diagnosing C-RBSIs. We conducted a retrospective study of episodes in which E. coli was isolated from catheter lumens obtained using the DTTP technique. Microbiological and clinical data were obtained based on the DTTP technique as either catheter colonization, C-RBSI, or non-C-RBSI. A total of 89 catheter blood cultures were included, classified as follows: catheter colonization, 33.7%; C-RBSI, 9.0%; and non-C-RBSI, 57.3%. Only 15.7% of the catheters were withdrawn, with no positive catheter-tip cultures. We found no statistically significant differences in catheter type, antibiotic treatment, or clinical outcome among the groups, except for the frequency of catheter lock therapy or in the frequency of successful treatment. Mortality was associated with C-RBSI in only one patient. E. coli bacteremia diagnosed by the DTTP technique was classified as non-catheter-related in most patients. As the majority of the catheters were retained, E. coli bacteremia could not be microbiologically confirmed as catheter-related by the catheter-tip culture. Future studies are needed to assess the profitability of the DTTP technique for diagnosing E. coli C-RBSIs.

Effect of Central Line Duration and Other Risk Factors on Central Line-Associated Bloodstream Infection in Severe Adult Burns Patients at a Large Tertiary Referral Burns Centre: A 5-Year Retrospective Study

Central line-associated bloodstream infection (CLABSI) and catheter-related bloodstream infection (CLABSI with a positive catheter tip culture, CRBSI) are preventable causes of morbidity and mortality for severe adult burns patients. Routine central line changes as a CLABSI prevention strategy in burns patients is controversial due to the paucity of evidence to guide the appropriate timing of line changes. This study aimed to address this evidence gap by investigating risk factors associated with central line sepsis, including the duration of central line insertion, in a population of severe adult burns patients (burns involving ≥20% total body surface area (TBSA)) admitted to the Royal Brisbane and Women’s Hospital Intensive Care Unit over five years (2015–2019 inclusive). On multivariate analysis, central line duration and burn TBSA were identified as independent risk factors for CLABSI, with central line duration the most significant predictor (p = 0.0008; OR 1.177, 95% CI 1.072–1.299). No risk factor independently predicted CRBSI. CLABSI detection occurred a median of 8.5 days (IQR 6.0–11.0) post central line insertion. These findings suggest further research to assess the efficacy of routine line changes prior to the at-risk period of 6–11 days post central line insertion in reducing CLABSI in severe adult burns patients may be beneficial.

Not just vegetations: focal myocardial changes in patients with fungal infections.

Fungal endocarditis classically involves dense heterogenous vegetations. However, several patients with fungal infections were noted to have myocardial changes ranging from focal brightening to nodular thickening of chordae or papillary muscles. This study evaluates whether these findings are associated with fungal infections. In a retrospective case-control study, paediatric inpatients with fungal infections (positive blood, urine, or catheter tip culture) in a 5-year period were matched 1:1 to inpatients without positive fungal cultures. Echocardiograms were scored on a 5-point scale by two independent readers for presence of myocardial brightenings, nodular thickenings, and vegetations. Clinical data were compared. Of 67 fungal cases, positive culture sites included blood (n = 44), vascular catheter tip (n = 7), and urine (n = 29); several had multiple positive sites. "Positive" echo findings (score ≥ 2+) were more frequent in the Fungal Group (33 versus 18%, p = 0.04). Fungal Group patients with "positive" versus "negative" echo findings had similar proportion of bacterial infections. Among fungal cases, those with "positive" echo findings had longer hospital length of stay than cases with "negative" echos (median 58 versus 40 days, p = 0.03) but no difference in intensive care unit admission, extracorporeal membranous oxygenation support, or mortality. Myocardial and papillary muscle brightening with nodular thickening on echocardiogram appear to be associated with fungal infections. There may be prognostic implications of these findings as patients with "positive" echo have longer length of stay. Further studies are needed to better understand the mechanism and temporal progression of these changes and determine the prognostic value of this scoring system.

Role of Venous Access Port Cultures in the Management of Port-Related Infections

PurposeTo determine the impact of port and catheter tip cultures on the clinical management of port-related infections. Materials and MethodsPatients whose ports were removed for infection between January 2016 and December 2019 were retrospectively identified. The study sample included 68 ports removed for suspected catheter-related bloodstream infection (CRBSI) and 27 ports removed for local infection. Port surface, catheter tip, and blood culture results were recorded. Antimicrobial therapy before and after port removal was recorded. The impact of culture results on port infection management was determined. ResultsOf the 68 ports removed from patients with CRBSI, 78% received empiric antibiotics. Of these patients, blood cultures led to a change in therapy in 77%. Catheter tip cultures were positive in 32% whereas port surface cultures were positive in 53% of patients. Culture results did not influence antimicrobial therapy in any patient with CRBSI. Of 27 port removals performed for local infection, catheter tip cultures were positive in 41% whereas port surface cultures were positive in 59% of patients. Port surface cultures led to a change in therapy in 33% of local infections. Port surface cultures were significantly more likely to impact management if removal was performed for local infection than for CRBSI (33% vs. 0%, respectively; P < .001). Port surface cultures were inclusive of all positive catheter tip cultures. ConclusionsFor patients with suspected CRBSI, blood cultures alone are sufficient to guide therapy. Port cultures may be justified in the setting of local infection. Catheter tip cultures are unnecessary if port surface cultures are performed.

Analysis of the Rate and Pattern of Ventriculoperitoneal Shunt Infection and Ventricular Catheter Culture Yield: A 10-Year Single-Institute Experience

Aim: We aimed to study the rate and pattern of ventriculoperitoneal shunt (VPS) infections at the Jordan University Hospital (JUH) over 10 years and investigate the yield of ventricular catheter tip culture in the evaluation of shunt infection. Patients and Methods: All patients operated on at our institution for ventriculoperitoneal shunt (VPS) insertion, reinsertion, and revision between 2009 and 2018 were included. Data (age, gender, pathology, and history of shunt infection) were collected from patients’ files. Rates of infection and results of culture (cerebrospinal fluid and ventricular catheter tip) were obtained from laboratory records. Results: According to our hospital database, 310 patients were eligible for this study. The rate of infection was 11.1% per ventriculoperitoneal procedure, and the most common ­organism was coagulase-negative Staphylococcus (CoNS) which was the cause of infection in 51.4% of the cases. Twenty-one percent of proved shunt infection cases showed a positive ventricular catheter tip culture. Conclusion: The rate and pattern of shunt infections at our institution are comparable with the international figures and data. Methods of catheter tip culturing should be improved to increase the yield of this practice.

3:45 PM Abstract No. 360 Predictors of catheter-related infections of tunneled lines in the inpatient setting

Inpatients with central venous catheters (CVCs) that show signs of local or systemic infection may undergo CVC removal followed by catheter tip culture for confirmation of catheter-related infections (CRI) and catheter-related bloodstream infections (CRBSI), as defined by positive catheter tip culture with a congruent positive blood culture. The use of this test has dwindled over the past decade, owing to factors including reimbursement penalties, poor predictive value, and increased reliance on blood cultures (BCx). We aim to develop a clinical risk calculator to reduce unnecessary removal and catheter tip culture. This IRB-approved retrospective study examined 151 patients in the inpatient setting who underwent tunneled CVC removal and tip culture. The primary outcome was the presence of CRI as defined by a positive catheter tip culture. Subgroup analysis was performed to determine which clinical factors results influenced the presence of CRI. All analyses were performed using χ2 analysis, and binary logistic regression with backward elimination. In this cohort, the median age at placement was 52 years, and median catheter-days was 98 days. Of the 151 lines removed, 32 patients (21%) had CRBSI and 43(29%) of catheter tips were culture positive. Variables predictive of CRI were gram-positive BCx prior to line removal and access site purulence (OR = 2.2 and OR = 4.0, P < 0.05). Variables that were not predictive of CRI included: fungal BCx, access site and laterality, CVC type, white count, placement indication, catheter tip location, signs of systemic infection, tenderness, and erythema. While not in the final model, CVC cultures with gram-negative organisms were related to the absence of CRIs (χ2 value = 3.6, P < 0.05). In this population, it is important to discern high-risk patients. Our model demonstrates feasibility of a risk calculator in the setting of possible CRI. When choosing a course of action, clinicians may consider removing CVCs in the presence of purulence or gram-positive BCx, and conversely, treating through non-gram positive BCx infections. Limitations of the study include cohort size and antibiotics given before cultures.

Abstract No. 654 Evaluating the value of clinical predictors in determining catheter-related infections

Patients with central venous catheters (CVCs) that show signs of infection may undergo CVC removal and catheter tip culture for confirmation of catheter-related infections (CRI). When suspicious of a CRI, a clinician’s decision-making is influenced by various physical examination and lab findings. Thus, it is helpful to understand the utility of certain risk factors and tests. To study the advantages of each, we assessed the sensitivity, specificity, and association of common clinical findings using CVC-tip culture as our primary endpoint. Under an IRB-approved protocol, 151 patients in the inpatient setting, who underwent tunneled CVC removal and tip culture, were retrospectively analyzed. Outcomes were stratified based on CRI, defined as a positive catheter-tip culture. All analyses were performed using χ2, sensitivity and specificity analysis in SPSS 24. In this cohort, the median age at placement was 52 years, and 43 CVC tip cultures (29%) were found to be positive; only 32 (21%) exhibited concurrent bacteremia. None of the physical examination findings (purulence, erythema, tenderness, fever, and cutaneous/systemic signs) were individually associated with a CRI. However, owing to their high specificity and low P values on χ2 testing, fever, purulence, and tenderness were grouped into their criteria, defined by presence of at least one of such findings. The resultant variable demonstrated a χ2 value of 4.5 (P = 0.03), a sensitivity of 77%, and a specificity of 42%. Presence of a gram-positive BCx was associated with CRIs (P = 0.04), and gram-negative BCx results were associated with no growth on catheter-tip culture (P = 0.04). Neither high nor low white counts were associated with CRIs. This analysis suggests that physical exam findings should be used in summation rather than individually when determining a patient’s CRI risk. When deciding their course of action, clinicians may consider removing CVCs in the presence of gram-positive bacteremia, and conversely, deferring CVC removal and treating through confirmed gram-negative bacteremia. Study limitations include cohort size and inconsistency of physical examination reporting.

Totally implantable central venous device-associated blood stream infection in elderly malignant disease patients.

We investigated the rate of bloodstream infections in elderly malignant disease patients whose totally implantable central venous device (CV ports) had been removed for any reason at our hospital. We evaluated 22 elderly malignant disease patients who had had their CV ports removed for any reason between May 2014 to April 2015. The patients were 12 males and 10 females between 62 and 86 years of age with a median age of 75.5 years. The catheter tip cultures were positive in 6 out of 22 cases (27.3%). Gram-positive cocci were detected in 5 cases, and gram-positive bacilli were detected in 1 case. Five of these 6 cases (83%) found to have positive catheter tip cultures were cultured at the time of death. In addition, 5 of the 13 catheters removed at the time of death resulted in positive culture results (38%). The positive culture ratio correlated well with the ratio of death and the age in cases of hematopoietic tumors. In cancer patients, the CV port is frequently used for the delivery of anti-cancer medicines. However, CV port infections are underestimated and typically not recognized in a timely manner. Patients suspected of having a CV port infection should be closely observed and the catheter removed immediately. However, it is very difficult to decide to discontinue a CV port, since its removal may render patients more susceptible to blood stream infections due to their poor general health and old age. CV port use should be considered in such cases to prevent future blood stream infections.

Contemporary Insertion of Central Venous Access Catheters in Pediatric Patients: A Retrospective Record Review Study of 538 Catheters in a Single Center.

To analyze the rate of infections and complications after surgeon-performed, largely ultrasound-guided, central venous catheter (CVC) placement in a pediatric population and to identify patients at high risk of complications. All children aged between 4 months and 19 years with a percutaneous CVC inserted between January 1, 2000, and July 31, 2013, were included. Patient records were reviewed retrospectively for the occurrence of infection and other complications until CVC removal or the last outpatient clinic visit and compared between patient groups and with the recent literature. A total of 538 CVCs were placed in 345 patients. Eight patients (1.5%) suffered complications during placement. There were 84 cases of a suspected CVC infection (15.6%). Catheter-related infections with a positive catheter tip culture occurred in 25 cases (4.6%). Older patients (odds ratio [OR] 0.88; 95% confidence interval [CI] 0.78-0.98) or patients with a double-lumen 7 French Bard-Hickman catheter (OR 0.32; 95% CI 0.11-1.00) had a significantly lower risk of infection. Older patients (OR 0.94; 95% CI 0.89-0.99) and patients with beta-thalassemia (OR 0.35; 95% CI 0.17-0.71) also had a significantly lower risk of suspected infection. In general, infection rates in our series were similar to those in the recent literature. Younger patients seem to be at higher risk for CVC removal because of infection prior to the end of treatment. Patients with beta-thalassemia or receiving a double-lumen 7F Bard-Hickman catheter had a lower risk of infection.

Non-imaging assisted insertion of un-cuffed, non-tunneled internal jugular venous catheters for hemodialysis: Safety and utility in modern day world

BackgroundAbsolute necessity in acute kidney injury (AKI) and ignorance in chronic kidney disease (CKD) make the use of un-cuffed, non-tunneled catheters an indispensable vascular access for hemodialysis. Although these catheters should be inserted under radiological guidance, it may not be feasible in certain circumstances. The aim of the present study was to evaluate safety and outcome of non-imaging assisted insertion of these catheters in internal jugular vein (IJV) for hemodialysis. MethodsWe analyzed 233 attempts of non-imaging assisted un-cuffed, non-tunneled IJV catheterization at our center. The immediate insertion complications, duration of use, rate and type of infection and other complications were assessed. ResultsOut of the 233 attempts, 223 (213-right, 10-left) were successful. The most common indication was AKI (n = 127, 54.5%), followed by CKD (n = 99, 42.5%). Successful catheterization at first attempt was achieved in 78.9%. Insertion complications were noted in 12.8% and included arterial puncture (5.2%), hematoma (3.0%) and malposition (2.1%). Amongst 219 catheters followed for 4825 days, the mean duration of use was 22 days. Catheter related infections occurred in 42 patients with an incidence of 8.7 per 1000 catheter days. Bacteraemia was present in 10/36 cases (27.7%), positive catheter tip cultures in 71.4% cases and staphylococcal species were the most common organism. Cumulative hazard analysis by Cox regression revealed a linear increase in the risk for infection with each week. ConclusionNon-imaging assisted insertion of uncuffed, non-tunneled catheters is associated with slightly higher rate of insertion complication but comparable outcome in terms of infection rate or days of use.

Comparison of alcoholic chlorhexidine and povidone-iodine cutaneous antiseptics for the prevention of central venous catheter-related infection: a cohort and quasi-experimental multicenter study.

Compare the effectiveness of different cutaneous antiseptics in reducing risk of catheter-related infection in intensive care unit (ICU) patients. We compared the risk of central venous catheter-related infection according to four-step (scrub, rinse, dry, and disinfect) alcoholic 5% povidone-iodine (PVI-a, n=1521), one-step (disinfect) alcoholic 2% chlorhexidine (2% CHX-a, n=1116), four-step alcoholic <1% chlorhexidine (<1% CHX-a, n=357), and four-step aqueous 10% povidone-iodine (PVI, n=368) antiseptics used for cutaneous disinfection and catheter care during the 3SITES multicenter randomized controlled trial. Within this cohort, we performed a quasi-experimental study (i.e., before-after) involving the four ICUs which switched from PVI-a to 2%CHX-a. We used propensity score matching (PSM, n=776) and inverse probability weighting treatment (IPWT, n=1592). The end point was the incidence of catheter-related infection (CRI) defined as catheter-related bloodstream infection (CRBSI) or a positive catheter tip culture plus clinical sepsis on catheter removal. In the cohort analysis and compared with PVI-a, the incidence of CRI was lower with 2%CHX-a [adjusted hazard ratio (aHR), 0.51; 95% confidence interval (CI) (0.28-0.96), p=0.037] and similar with <1%CHX-a [aHR, 0.73; (0.36-1.48), p=0.37] and PVI [aHR, 1.50; 95% CI (0.85-2.64), p=0.16] after controlling for potential confounders. In the quasi-experimental study and compared with PVI-a, the incidence of catheter-related infection was again lower with 2%CHX-a after PSM [HR, 0.35; 95% CI (0.15, 0.84), p=0.02] and in the IPWT analysis [HR, 0.31; 95% CI (0.14, 0.70), p=0.005]. The incidence of CRBSI or adverse event was not significantly different between antiseptics in all analyses. In comparison with PVI-a, the use of 2%CHX-a for cutaneous disinfection of the central venous catheter insertion site and maintenance catheter care was associated with a reduced risk of catheter infection, while the benefit of <1%CHX-a was uncertain. NCT01479153.

Bacterial colonization of epidural catheters used for short-term postoperative analgesia: a microbiological examination and risk factor analysis

Background: Epidural catheter-related infections are very rare, but if occurs, the complications are debilitating and life-threatening. The route by which the infection spreads is still under debate with the prime suspected route being direct spread with migration along the epidural catheter. Objective: To critically analyze the incidence of epidural catheter-related infections, correlate the proposed risk factors leading to infection, and come up with a time frame at which the catheter should be ideally removed. Material and Methods: A prospective observational study was done to study the incidence of epidural catheter-related infections and to find the bacteriological profile associated with epidural catheter-related infections. Ninety patients of ASA I and II aged between 18 and 65 years scheduled for elective surgeries requiring epidural catheter for intraoperative and postoperative analgesia were randomly allocated into three groups. Groups I, II, and III consisted of 30 patients each, and the epidural catheters were removed aseptically after 24, 48, and 72 h, respectively, and the catheter tips were sent for microbial culture examination. Result: There was no incidence of epidural infections during the whole study. The incidence of bacterial colonization over epidural catheter tip in our study was 7.1% with “coagulase-negative Staphylococcus epidermidis” as the most common organism. Among the various risk factors studied, we found significant correlation only to that of the duration of catheter in situ with that of the positive catheter tip cultures, with 85.7% of the positive cultures from group III. Conclusion: It is not advisable to allow the epidural catheters to be in situ for more than 72 h to avoid the chances of epidural catheter-related infections.

Positive tip culture with Candida and negative blood culture: to treat or not to treat? A systematic review with meta-analysis.

Invasive candidiasis is a major invasive fungal infection. It has high lethality, and even higher if not treated early. There is no consensus on antifungal treatment in patients with positive catheter tip culture for Candida spp. The objective of this study was to evaluate the impact of antifungal therapy and mortality of patients with positive culture for Candida spp. in catheter tip that have negative blood culture. The PubMed database was searched to identify articles related to Candida and catheter. Articles with adequate data were included. Of 1208 studies initially screened, 5 met the selection criteria. All were retrospective studies. In all, 265 patients were evaluated for outcomes 'candidemia' and 'invasive candidiasis' and 158 for the outcome 'mortality.' Antifungal therapy had no impact on the development of invasive fungal disease (Odds ratio (OR) = 1.41; 95% confidence interval (CI) = 0.56-3.52). Also there was no benefit of therapy on mortality (OR = 1.02; 95% CI = 0.54-1.95). Due to the poor quality of the studies no conclusion can be made. Randomized prospective studies are needed to better evaluate this therapeutic strategy.

PO-0546 Lessons From 10 Years Of Invasive Fungal Infection At Singapore General Hospital Nicu: Epidemiology, Risks, Clinical Course And Outcomes

Introduction Invasive fungal infections (IFI) in preterm neonates are rare, but associated with increased mortality and morbities, both short and long term. IFIs in preterms are also increasing globally. Aims To review the epidemiology, risk factors, clinical course and outcomes of all IFIs in newborns at Singapore General Hospital for the period 1/1/2002 to 31/7/2012. Methods Retrospective matched case-control study. Cases of IFI were matched 1:1 with another neonate of the same gestation in the same year of birth. Results 6 cases of IFI were matched with 6 controls. All were extremely low birth weight (ELBW) infants. Many IFI cases had risk factors for sepsis perinatally. Significant risk factors associated with IFI include surgery (OR 25.000 95% CI 1.200–520.734), more than 35 days of conventional ventilation (OR 25.000 95% CI 1.200–520.734), 9 lots of platelet transfusion or more (OR 7.000 95% CI 1.140–42.969), vancomycin (OR 25.000 95% CI 1.200–520.734) and cephalosporins (OR 6.000 95% CI 1.003–35.908). 5 out of 6 IFI presented with thrombocytopenia with elevated C-reactive protein. Other presentations included hypotension (3 out of 6), increased ventilation settings (2 out of 6) and leucopenia (2 out of 6). All IFIs were Candida albicans. Multiorgan involvement is prevalent. All 6 IFIs had positive endotracheal as well as urine cultures. 3 had positive catheter tip cultures, 2 had positive peritoneal fluid cultures, and 1 had positive blood culture. Conclusion Classical presentations and significant risk factors for IFI in ELBWs were identified which allowed earlier identification and possible modification of risks.

Genotypic study documents divergence in the pathogenesis of bloodstream infection related central venous catheters in neonates

ObjectiveTo investigate the pathogenesis of bloodstream infection by Staphylococcus epidermidis, using the molecular epidemiology, in high-risk neonates. MethodsWe conducted a prospective study of a cohort of neonates with bloodstream infection using central venous catheters for more than 24h. “National Healthcare Safety Network” surveillance was conducted. Genotyping was performed by DNA fingerprinting and mecA genes and icaAD were detected by multiplex-PCR. ResultsFrom April 2006 to April 2008, the incidence of bloodstream infection and central venous catheter-associated bloodstream infection was 15.1 and 13.0/1000 catheter days, respectively, with S. epidermidis accounting for 42.9% of episodes. Molecular analysis was used to document the similarity among six isolates of bloodstream infection by S. epidermidis from cases with positive blood and central venous catheter tip cultures. Fifty percent of neonates had bloodstream infection not identified as definite or probable central venous catheter-related bloodstream infection. Only one case was considered as definite central venous catheter-related bloodstream infection and was extraluminally acquired; the remaining were considered probable central venous catheter-related bloodstream infections, with one probable extraluminally and another probable intraluminally acquired bloodstream infection. Additionally, among mecA+ and icaAD+ samples, one clone (A) was predominant (80%). A polyclonal profile was found among sensitive samples that were not carriers of the icaAD gene. ConclusionsThe majority of infections caused by S. epidermidis in neonates had an unknown origin, although 33.3% appeared to have been acquired intraluminally and extraluminally. We observed a polyclonal profile between sensitive samples and a prevalent clone (A) between resistant samples.

The risk of catheter-related bloodstream infection after withdrawal of colonized catheters is low

Most episodes of catheter-related bloodstream infection (C-RBSI) are documented before or at the time of catheter withdrawal. The risk of C-RBSI in the period after removing a colonized catheter in patients without bacteremia (late C-RBSI) is unknown. We assessed the risk of developing a late C-RBSI episode in an unselected population with positive catheter tip cultures and analyzed associated risk factors. We analyzed retrospectively all colonized catheter tips between 2003 and 2010 and matched them with blood cultures. C-RBSI episodes were classified as early C-RBSI (positive blood cultures were obtained ≤24 h after catheter withdrawal) or late C-RBSI (positive blood cultures were obtained ≥24 h after catheter withdrawal). We analyzed the risk factors associated with late C-RBSI episodes by comparison with a selected group of early C-RBSI episodes. We collected a total of 17,981 catheter tips: 4,533 (25.2 %) were colonized. Of them, 1,063 (23.5 %) were associated to early C-RBSI episodes and from the remaining 3,470, only 143 (4.1 %) were associated to late C-RBSI episodes. Then, they corresponded to 11.9 % of the total 1,206 C-RBSI episodes. After comparing early and late C-RBSI episodes, we found that late C-RBSI was significantly associated with the presence of methicillin-resistant Staphylococcus aureus (MRSA, p = 0.028) and with higher mortality (p = 0.030). According to our data, patients with colonized catheter tips had a 4.1 % risk of developing late C-RBSI, which was associated with higher crude mortality.

Clinical significance of multidrug-resistant Acinetobacter baumannii isolated from central venous catheter tip cultures in patients without concomitant bacteremia

The purpose of this study was to examine the clinical implications of a positive central venous catheter (CVC) tip culture with multidrug-resistant Acinetobacter baumannii (MRAB) in patients without concurrent bacteremia. This retrospective, multicenter study was conducted in 9 teaching hospitals in the Republic of Korea from May 2008 to April 2012. Study subjects included adult patients (aged ≥ 18 y) who yielded an MRAB-positive CVC tip culture without concurrent MRAB bacteremia. All patients were observed for the development of subsequent MRAB bacteremia for 6 months after CVC removal. Multivariable Firth logistic regression analysis was performed to determine predictors independently associated with subsequent MRAB bacteremia. During the study period, subsequent MRAB bacteremia was observed in 18.8% of patients (21/112). Of the 112 patients, 23 (20.5%) did not show systemic inflammatory response syndrome (SIRS). None of the 23 patients without SIRS presented with subsequent MRAB bacteremia. Multivariable logistic regression analysis showed that prior administration of carbapenems (odds ratio (OR) 7.04, 95% confidence interval (CI) 1.43-34.77) or corticosteroids (OR 6.67, 95% CI 1.19-37.44), and C-reactive protein ≥ 40 mg/l (OR 18.11, 95% CI 2.22-148.07) were positive predictive factors. Prior acquisition of MRAB at a site other than the catheter (OR 0.10, 95% CI 0.03-0.39) was a negative predictive factor for developing MRAB bacteremia. Our results suggest that patients with a CVC tip colonized with MRAB should be closely monitored for signs and symptoms of subsequent MRAB bacteremia.

Vascular Catheter Tip Cultures for Suspected Catheter-Related Blood Stream Infection in the Intensive Care Unit: A Tradition Whose Time Has Passed?

Catheter-related blood stream infections (CR-BSIs) are estimated to occur in 80,000 patients in intensive care units (ICUs) each year in the United States. We sought to determine the clinical utility of vascular catheter cultures in critically ill patients with suspected CR-BSI. We reviewed retrospectively all positive (≥15 colony forming units/roll) vascular catheter tip cultures (CTCs) documented over a four-year period in the ICUs of two hospitals. A CR-BSI was defined as matching positive blood and catheter cultures. The time interval between catheter removal and blood culture was recorded. A total of 1,391 CTCs were obtained, of which 468 (34%) were positive and 143 (31% of the positive cultures) were associated with a diagnosis of CR-BSI. In 133 of these 143 cases (93%), the positive blood culture was obtained before or within 24 h after catheter removal and dictated antibiotic therapy. In only 10 of 143 cases (7%) did catheter removal and culture significantly (>1 day) precede the positive blood culture. In 55% of the CR-BSI cases, the catheter was removed empirically and close to the time of blood culture (-1.3±19.0 h). In the remaining 45%, the catheter was removed clinically (after a blood culture was positive), and this action was more remote in time (23.6±19.4 h; p<0.001 vs. empiric removal). Total microbiology laboratory costs for the CTCs were $75,300, and 600 microbiology technician hours were required. In an ICU patient population, only about one-third of vascular catheter cultures were positive, and only about one-third of the positive CTCs were associated with CR-BSI. Ninety-three percent of all CR-BSIs were identified by bacteremia either before or coinciding with catheter removal, and the results of the blood culture dictated antimicrobial therapy. Because CTCs rarely changed therapy, they may not be appropriate in the management of suspected CR-BSI in the ICU setting.

Bacteremic complications of intravascular catheter tip colonization with Gram-negative micro-organisms in patients without preceding bacteremia

Although Gram-negative micro-organisms are frequently associated with catheter-related bloodstream infections, the prognostic value and clinical implication of a positive catheter tip culture with Gram-negative micro-organisms without preceding bacteremia remains unclear. We determined the outcomes of patients with intravascular catheters colonized with these micro-organisms, without preceding positive blood cultures, and identified risk factors for the development of subsequent Gram-negative bacteremia. All patients with positive intravascular catheter tip cultures with Gram-negative micro-organisms at the University Medical Center, Utrecht, The Netherlands, between 2005 and 2009, were retrospectively studied. Patients with Gram-negative bacteremia within 48 h before catheter removal were excluded. The main outcome measure was bacteremia with Gram-negative micro-organisms. Other endpoints were length of the hospital stay, in-hospital mortality, secondary complications of Gram-negative bacteremia, and duration of intensive care admission. A total of 280 catheters from 248 patients were colonized with Gram-negative micro-organisms. Sixty-seven cases were excluded because of preceding positive blood cultures, leaving 213 catheter tips from 181 patients for analysis. In 40 (19%) cases, subsequent Gram-negative bacteremia developed. In multivariate analysis, arterial catheters were independently associated with subsequent Gram-negative bacteremia (odds ratio [OR] = 5.00, 95% confidence interval [CI]: 1.20–20.92), as was selective decontamination of the digestive tract (SDD) (OR = 2.47, 95% CI: 1.07–5.69). Gram-negative bacteremia in patients who received SDD was predominantly caused by cefotaxime (part of the SDD)-resistant organisms. Mortality was significantly higher in the group with subsequent Gram-negative bacteremia (35% versus 20%, OR = 2.12, 95% CI: 1.00–4.49). Patients with a catheter tip colonized with Gram-negative micro-organisms had a high chance of subsequent Gram-negative bacteremia from any cause. This may be clinically relevant, as starting antibiotic treatment pre-emptively in high-risk patients with Gram-negative micro-organisms cultured from arterial intravenous catheters may be beneficial.