Semiquantitative culture of subcutaneous segment for conservative diagnosis of intravascular catheter-related infection

Skin insertion site culture for the prediction of primary bloodstream infection

Purpose

Previous studies have analyzed the capability of skin insertion site culture to predict catheter-related bloodstream infection (CRBSI). However, there has been not analyzed its capability to predict primary bloodstream infection (PBSI), that include CRBSI and bloodstream infection of unknown origin (BSIUO). The novel objective of our study was to determine the capability of insertion skin site culture to predict CRBSI and primary bloodstream infection (PBSI), that include CRBSI and bloodstream infection of unknown origin (BSIUO).

Material and methods

Observational and prospective study in one Intensive Care Unit. Patients with some central venous catheter (CVC) at least during 7 days and suspected catheter-related infection (CRI) (new episode of fever or sepsis) were included. Cultures of insertion skin site, paired blood samples, catheter-tip, and other clinical samples were taken. Capability of insertion skin site culture to predict CRBSI and PBSI was determined.

Results

We included 108 CVC from 96 CRI suspicion episodes. The causes that motivated CRI suspicion were 20 (18.5%) PBSI, 44 (40.7%) other infections, and 44 (40.7%) unknown. Among the 20 PBSI, 11 (55%) were CRBSI and 9 (45%) were BSIUO. Negative predictive value of insertion skin site culture to predict CRBSI was 95% (87–98%) and to predict PBSI was 85% (76–91%).

Conclusions

The new finding of our study was that skin insertion site culture had a good negative predicted valued for the prediction of CRBSI and PBSI.

Comparison of semi-quantitative and quantitative methods for diagnosis of catheter-related blood stream infections: a systematic review and meta-analysis of diagnostic accuracy studies

Catheter-related blood-stream infections (CRBSIs) are the most common healthcare-associated blood-stream infections. They can be diagnosed by either semi-quantitative or quantitative methods, which may differ in diagnostic accuracy. A meta-analysis was undertaken to compare the diagnostic accuracy of semi-quantitative and quantitative methods for CRBSI. A systematic search of Medline, Scopus, Cochrane and Embase databases up to January 2020 was performed and subjected to a QUADAS (quality assessment of diagnostic accuracy studies 2) tool to evaluate the risk of bias among studies. The pooled sensitivity and specificity of the methods were determined and heterogeneity was evaluated using the χ2 test and I2. Publication bias was assessed using a Funnel plot and the Egger's test. In total, 45 studies were analysed with data from 11 232 patients. The pooled sensitivity and specificity of semi-quantitative methods were 85% (95% CI 79-90%) and 84% (95% CI 79-88%), respectively; and for quantitative methods were 85% (95% CI 79-90%) and 95% (95% CI 91-97%). Considerable heterogeneity was statistically evident (P < 0.001) by both methods with a correspondingly symmetrical Funnel plot that was confirmed by a non-significant Deek's test. We conclude that both semi-quantitative and quantitative methods are highly useful for screening for CRBSI in patients and display high sensitivity and specificity. Quantitative methods, particularly paired quantitative cultures, had the highest sensitivity and specificity and can be used to identify CRBSI cases with a high degree of certainty.

Diagnosis and treatment of catheter-related bloodstream infection: Clinical guidelines of the Spanish Society of Infectious Diseases and Clinical Microbiology and (SEIMC) and the Spanish Society of Spanish Society of Intensive and Critical Care Medicine and Coronary Units (SEMICYUC)

Catheter-related bloodstream infections (CRBSI) constitute an important cause of hospital-acquired infection associated with morbidity, mortality, and cost. The aim of these guidelines is to provide updated recommendations for the diagnosis and management of CRBSI in adults. Prevention of CRBSI is excluded. Experts in the field were designated by the two participating Societies (the Spanish Society of Infectious Diseases and Clinical Microbiology and [SEIMC] and the Spanish Society of Spanish Society of Intensive and Critical Care Medicine and Coronary Units [SEMICYUC]). Short-term peripheral venous catheters, non-tunneled and long-term central venous catheters, tunneled catheters and hemodialysis catheters are covered by these guidelines. The panel identified 39 key topics that were formulated in accordance with the PICO format. The strength of the recommendations and quality of the evidence were graded in accordance with ESCMID guidelines. Recommendations are made for the diagnosis of CRBSI with and without catheter removal and of tunnel infection. The document establishes the clinical situations in which a conservative diagnosis of CRBSI (diagnosis without catheter removal) is feasible. Recommendations are also made regarding empirical therapy, pathogen-specific treatment (coagulase-negative staphylococci, Staphylococcus aureus, Enterococcus spp., Gram-negative bacilli, and Candida spp.), antibiotic lock therapy, diagnosis and management of suppurative thrombophlebitis and local complications.

Use of rapid diagnostic techniques in ICU patients with infections

Background

Infection is a common complication seen in ICU patients. Given the correlation between infection and mortality in these patients, a rapid etiological diagnosis and the determination of antimicrobial resistance markers are of paramount importance, especially in view of today's globally spread of multi drug resistance microorganisms. This paper reviews some of the rapid diagnostic techniques available for ICU patients with infections.

Methods

A narrative review of recent peer-reviewed literature (published between 1995 and 2014) was performed using as the search terms: Intensive care medicine, Microbiological techniques, Clinical laboratory techniques, Diagnosis, and Rapid diagnosis, with no language restrictions.

Results

The most developed microbiology fields for a rapid diagnosis of infection in critically ill patients are those related to the diagnosis of bloodstream infection, pneumonia -both ventilator associated and non-ventilator associated-, urinary tract infection, skin and soft tissue infections, viral infections and tuberculosis.

Conclusions

New developments in the field of microbiology have served to shorten turnaround times and optimize the treatment of many types of infection. Although there are still some unresolved limitations of the use of molecular techniques for a rapid diagnosis of infection in the ICU patient, this approach holds much promise for the future.

Diagnosis of central venous catheter-related bloodstream infection without catheter removal: A prospective observational study

BACKGROUND

Catheter-related bloodstream infections (CRBSI) resulting from bacterial colonisation of an intravascular catheter are the leading cause of nosocomially acquired sepsis contributing significantly towards in-hospital morbidity and mortality. Suspicion of central venous CRBSI leads frequently to catheter withdrawal but not all infection requires the catheter to be withdrawn; therefore, diagnosis of central venous CRBSI without catheter withdrawal is a necessity.

METHODS

The study was prospectively performed in a cohort of adult patients who had short term central venous catheter use. The samples collected from each patients included, skin swab from insertion site, swab from catheter hub, paired blood samples from catheter and from the peripheral vein for quantitative blood culture collected within 15 min of each other and catheter-tip sample by cutting off the tip (distal 5-cm segment). All samples were processed immediately.

RESULTS

50 episodes of clinical sepsis involving 100 patients occurred in the study population. 28 of the episodes were confirmed as CR-BSI (56%). Blood culture from the central venous catheter had the highest sensitivity (71.43%) and the greatest negative predictive value (86.67%). However, the peripheral blood culture was most specific and had the highest positive predictive value (specificity75%; positive predictive value 50%). The most accurate technique was differential quantitative blood cultures (accuracy 72%), followed by semiquantitative superficial cultures (accuracy 68%), although there were no statistically significant differences between values.

CONCLUSION

We recommend combining semiquantitative cultures and peripheral blood cultures to screen for CR-BSI, leaving differential quantitative blood cultures as a confirmatory and more specific technique.

Central venous catheter-related bloodstream infections in the intensive care unit

CONTEXT

Central venous catheter-related bloodstream infection (CRBSI) is associated with high rates of morbidity and mortality in critically ill patients.

AIMS

This study was conducted to determine the incidence of central venous catheter-related infections (CRIs) and to identify the factors influencing it. So far, there are very few studies that have been conducted on CRBSI in the intensive care unit in India.

SETTINGS AND DESIGN

This was a prospective, observational study carried out in the medical intensive care unit (MICU) over a period of 1 year from January to December 2004.

MATERIALS AND METHODS

A total of 54 patients with indwelling central venous catheters of age group between 20 and 75 years were included. The catheters were cultured using the standard semiquantitative culture (SQC) method. Statistical analysis used SPSS-10 version statistical software.

RESULTS

A total of 54 CVC catheters with 319 catheter days were included in this study. Of 54 patients with CVCs studied for bacteriology, 39 (72.22%) catheters showed negative SQCs and also negative blood cultures. A total of 15 (27.77%) catheters were positive on SQC, of which 10 (18.52%) were with catheter-associated infection and four (7.41%) were with catheter-associated bacteremia; the remaining one was a probable catheter-associated bacteremia. CRIs were high among catheters that were kept in situ for more than 3 days and emergency procedures where two or more attempts were required for catheterization (P < 0.05). In multivariate analysis of covariance duration of catheter in situ for >3 days, inexperienced venupucturist, more number of attempts and emergency CVC were associated with more incidence of CVCBSIs, with P <0.02. The duration of catheter in situ was negatively correlated (-0.53) and number of attempts required to put CVC was positively correlated (+0.39) with incidence of CVCBSIs. Sixty-five percent of the isolates belonged to the CONS group (13/20). Staphylococcus epidermidis showed maximum susceptibility to amikacin, doxycycline and amoxycillin with clavulanic acid and was susceptible to vancomycin (100%). Klebsiella pneumoniae was 100% susceptible to amikacin and ciprofloxacin. Escherichia coli was susceptible to amikacin and cefotaxime.

CONCLUSIONS

The overall incidence of CRI was 27.77% (15/54). Catheter-associated BSIs were 47.31 per 1000 catheter-days. CRI was low in the catheters inserted by the experienced venipuncturists, elective procedure and CVC kept in situ for ≤3 days. S. epidermidis was the most common isolate.

Empiric therapy for intravenous central line infections and nosocomially-acquired acute bacterial endocarditis

Intravascular catheters are essential devices in the intensive care unit, yet catheter-related bloodstream infections (CR-BSI) are associated with increased morbidity and mortality, prolonged hospitalization, and increased medical costs. Management of a CR-BSI requires antibiotics, with or without catheter removal, depending on patient and etiologic factors. Because of the high frequency of staphylococcal infections, it is wise to use a glycopeptide empirically. Extra coverage for Gram-negative bacilli should be administered in severely ill or immunocompromised patients. Once culture and sensitivity results are known, antibiotic therapy can be more selective.

Intravascular catheter-related infections: advances in diagnosis, prevention, and management

Indwelling vascular catheters are a leading source of bloodstream infections in critically ill patients and cancer patients. Because clinical diagnostic criteria are either insensitive or non-specific, such infections are often overdiagnosed, resulting in unnecessary and wasteful removal of the catheter. Catheter-sparing diagnostic methods, such as differential quantitative blood cultures and time to positivity have emerged as reliable diagnostic techniques. Novel preventive strategies include cutaneous antisepsis, maximum sterile barrier, use of antimicrobial catheters, and antimicrobial catheter lock solution. Management of catheter-related bloodstream infections involves deciding on catheter removal, antimicrobial catheter lock solution, and the type and duration of systemic antimicrobial therapy. Such decisions depend on the identity of the organism causing the bloodstream infection, the clinical and radiographical manifestations suggesting a complicated course, the underlying condition of the host (neutropenia, thrombocytopenia), and the availability of other vascular access sites.

A randomized and prospective study of 3 procedures for the diagnosis of catheter-related bloodstream infection without catheter withdrawal

BACKGROUND

Suspicion of catheter-related bloodstream infection (CR-BSI) leads frequently to unnecessary catheter withdrawals, and many catheter-tip cultures yield negative results. The objective of this study was to compare the yield of 3 microbiological procedures to assess CR-BSI without catheter withdrawal.

METHODS

The study was prospectively performed in a group of patients without neutropenia or blood disorders who were admitted to the intensive care unit during a 37-month period with sepsis suspected on clinical grounds and who had central venous catheters inserted for >48 h. The microbiological procedures compared were semiquantitative cultures from hub and skin (superficial), differential quantitative blood cultures, and differential time to positivity between cultures of blood obtained from catheter hubs and peripheral blood.

RESULTS

Of the 204 episodes of suspected CR-BSI included in the study, 28 were confirmed to be CR-BSI. We obtained the following results for sensitivity, specificity, positive and negative predictive values, and accuracy: superficial cultures, 78.6%, 92.0%, 61.1%, 96.4%, and 90.2%, respectively; differential quantitative blood cultures, 71.4%, 97.7%, 83.3%, 95.6%, and 94.1%, respectively; and differential time to positivity, 96.4%, 90.3%, 61.4%, 99.4%, and 91.2%, respectively.

CONCLUSIONS

CR-BSI can be assessed without catheter withdrawal in patients without neutropenia or blood disorders who have catheters inserted for a short time and are hospitalized in the intensive care unit. Convenience, use of resources, and expertise should determine the technique of choice in different medical contexts. Because of ease of performance, low cost, and wide availability, we recommend combining semiquantitative superficial cultures and peripheral vein blood cultures to screen for CR-BSI, leaving differential quantitative blood cultures as a confirmatory and more specific technique.

The risk of bloodstream infection in adults with different intravascular devices: a systematic review of 200 published prospective studies

OBJECTIVE

To better understand the absolute and relative risks of bloodstream Infection (BSI) associated with the various types of intravascular devices (IVDs), we analyzed 200 published studies of adults In which every device in the study population was prospectively evaluated for evidence of associated infection and microbiologically based criteria were used to define IVD-related BSI.

METHODS

English-language reports of prospective studies of adults published between January 1, 1966, and July 1, 2005, were identified by MEDLINE search using the following general search strategy: bacteremla [Medical Subject Heading, MeSH] OR septicemia [MeSH] OR bloodstream Infection AND the specific type of intravascular device (e.g., central venous port). Mean rates of IVD-related BSI were calculated from pooled data for each type of device and expressed as BSIs per 100 IVDs (%) and per 1000 IVD days.

RESULTS

Point incidence rates of IVD-related BSI were lowest with peripheral Intravenous catheters (0.1%, 0.5 per 1000 IVD-days) and midline catheters (0.4%, 0.2 per 1000 catheter-days). Far higher rates were seen with short-term noncuffed and nonmedicated central venous catheters (CVCs) (4.4%, 2.7 per 1000 catheter-days). Arterial catheters used for hemodynamic monitoring (0.8%, 1.7 per 1000 catheter-days) and peripherally inserted central catheters used in hospitalized patients (2.4%, 2.1 per 1000 catheter-days) posed risks approaching those seen with short-term conventional CVCs used in the Intensive care unit. Surgically implanted long-term central venous devices--cuffed and tunneled catheters (22.5%, 1.6 per 1000 IVD-days) and central venous ports (3.6%, 0.1 per 1000 IVD-days)--appear to have high rates of Infection when risk Is expressed as BSIs per 100 IVDs but actually pose much lower risk when rates are expressed per 1000 IVD-days. The use of cuffed and tunneled dual lumen CVCs rather than noncuffed, nontunneled catheters for temporary hemodlalysis and novel preventive technologies, such as CVCs with anti-infective surfaces, was associated with considerably lower rates of catheter-related BSI.

CONCLUSIONS

Expressing risk of IVD-related BSI per 1000 IVD-days rather than BSIs per 100 IVDs allows for more meaningful estimates of risk. These data, based on prospective studies In which every IVD in the study cohort was analyzed for evidence of infection by microbiologically based criteria, show that all types of IVDs pose a risk of IVD-related BSI and can be used for benchmarking rates of infection caused by the various types of IVDs In use at the present time. Since almost all the national effort and progress to date to reduce the risk of IVD-related Infection have focused on short-term noncuffed CVCs used in Intensive care units, Infection control programs must now strive to consistently apply essential control measures and preventive technologies with all types of IVDs.

Diagnosis of catheter-related bloodstream infection

Catheter-related bloodstream infection is a potentially serious condition with a mortality rate of 12% to 25%. Catheter-related bacteremia is difficult to diagnose, and clinical manifestations of the condition have proved to be unspecific and often inconclusive. Microbiologic techniques to diagnose catheter-related bloodstream infection have been developed, some of which require catheter removal whereas others do not. Differential time to positivity has demonstrated marked accuracy and practicality as it allows the catheter to remain in place. Many other methods, such as skin or hub cultures, show less remarkable results, and some, such as intraluminal brushing, may produce adverse effects. Once a catheter-related bloodstream infection is diagnosed, it is classified as either complicated or uncomplicated and treated accordingly.

The challenge of anticipating catheter tip colonization in major heart surgery patients in the intensive care unit: Are surface cultures useful?

OBJECTIVE

Patients undergoing heart surgery show a high risk of catheter colonization and catheter-related bloodstream infections. We evaluated whether skin insertion site and catheter hub surveillance cultures ("surface cultures") could predict catheter colonization and help establish the origin of bloodstream infections.

DESIGN

: Prospective cohort study.

SETTING

An 11-bed heart surgery intensive care unit in a tertiary university hospital.

PATIENTS

Heart surgery patients spending >4 days in intensive care over an 11-month period.

INTERVENTIONS

All catheters were surveyed. Cultures were obtained from the skin insertion site and all hubs on day 5 after surgery, every 72 hrs thereafter, and on catheter removal. Swabs were processed semiquantitatively by streaking the surface of a Columbia agar plate. Catheters were processed using Maki's method. The observation of > or = 15 colonies/plate was taken to indicate a positive skin or catheter colonization culture result.

MEASUREMENTS AND MAIN RESULTS

Over the study period, 561 catheters were inserted in 130 patients. The median time a catheter was in place was 6 days (interquartile range 3-11), and 3,712 surface cultures were obtained (median four per patient). Catheter colonization occurred in 133 catheters, and there were 15 episodes of catheter-related bloodstream infection (incidence density of colonization 29.3 and of catheter-related bloodstream infection 8.8 per 1,000 catheter-days). Validity indexes for the capacity of surface cultures to predict catheter colonization and catheter-related bloodstream infection, respectively, were as follows: accuracy, 71.4, 65.6; sensitivity, 83.5%, 100%; specificity, 67.1%, 64.7%; positive predictive value, 47.6%, 7.2%; negative predictive value, 91.9%, 100%; positive likelihood ratio, 2.5, 2.83; and negative likelihood ratio, 0.2, 0. Surface cultures correctly predicted 77.4% of all bacteremia episodes (catheter-related and non-catheter-related).

CONCLUSIONS

Systematic surveillance cultures of catheter hub and skin insertion sites in patients admitted to a heart surgery intensive care unit could help identify patients who would benefit from decontamination and preventive measures and establish whether catheters are the portal of entry of bloodstream infection.

Acridine orange leukocyte cytospin test for central venous catheter–related bloodstream infection: A pediatric experience

The aim of this study was to evaluate the acridine orange leukocyte cytospin (AOLC) test for the rapid diagnosis of septicemia caused by central venous catheters (CVCs), without removing the catheter, in a pediatric intensive care unit population. Twenty-six patients admitted in the pediatric intensive care unit of Azienda Ospedaliera "Ospedali Riuniti di Bergamo", Italy, were prospectively evaluated for CVC-related infection. Blood for culture was taken from all patients. Quantitative endoluminal cultures of the removed catheter tip by Cleri's technique and semiquantitative superficial cultures of the hub were performed. Gram staining and an AOLC smear were done according to Kite's technique. Four Staphylococcus CVC-related bloodstream infections were identified. CVC colonization was detected in 8 patients. Four had septicemia (Enterococcus faecalis, Escherichia coli, Klebsiella oxytoca, Candida glabrata) without CVC involvement. However, Gram staining and the AOLC test were negative in all cases. We conclude that cytocentrifugation and acridine orange staining of blood withdrawn by Kite's method from an in situ catheter, although simple, quick, and inexpensive, did not aid diagnosis in this pediatric population.

Catheter-related infections: diagnosis and intravascular treatment

The diagnosis of catheter-related infections relies on the presence of clinical manifestations of infection and the evidence of colonization of the catheter tip by bacteria, mycobacteria, or fungi. The reference method to confirm the latter requires the withdrawal of the catheter for culturing, which frequently turns out to be inconvenient, unnecessary and costly. New methods try to avoid these drawbacks and to assess the presence of tip colonization without withdrawal. Comparative quantitative blood cultures with a marked increase (> or = 5) in colony counts between blood obtained from the catheter lumen and from a peripheral vein simultaneously is one of those methods. It has a high sensitivity (>80%) and specificity (94-100%) but it is cumbersome and requires both an easy backflow of blood in the catheter and the existence of bacteremia. Cytocentrifugation and acridine orange staining of blood withdrawn from an infected catheter lumen has a sensitivity and a specificity of over 90% for the diagnosis of tip colonization. 'Superficial cultures' comprise the semiquantitative culture of the hub, of the skin surrounding the catheter entrance and of the first subcutaneous portion (1 cm) of the catheter after swabbing. The sensitivity of this method is >90%, specificity is >80%, and positive and negative predictive values for catheters (considering together those with and without clinical data of infection) are 66 and 97%, respectively. Endoluminal brushing has proved to be an impractical and unreliable procedure, at least in our experience. New methods based on the speed of bacterial growth to detectable levels of micro-organisms in conventional blood cultures are a new and interesting way of assessing catheter-related infections. Moreover, as the use of antimicrobial-coated catheters becomes more prevalent, the existing definitions of catheter colonization and catheter-related infection may need to be modified, because such coatings may lead to false-negative culture results. Many catheter infections, diagnosed without catheter withdrawal, can be handled nowadays with the so-called 'antibiotic lock-in technique', which consists in 'locking' the infected catheter lumen with a solution containing antibiotics. A high proportion of infected catheters, mainly those with coagulase-negative staphylococci, can be maintained in place and sterilized with this technique, including catheters in patients with therapeutic failure after receiving conventional intravenous antibiotic therapy. New diagnostic and therapeutic techniques may avoid the unnecessary withdrawal of thousands of efficient, difficult to replace and expensive intravascular lines.

Colonization and bacteremia risk factors in parenteral nutrition catheterization

AIMS

1) To establish the relationship between the kind of microorganism that colonizes parenteral nutrition catheters and several risk factors related to catheterization and patient characteristics. 2) To investigate the risk factors associated to bacteremia episodes originated in these colonized catheters.

METHOD

An observational, non-controlled, retrospective and cohorts study of the parenteral nutrition catheters implanted between 1988 and 1994 in our hospital. Risk factors were studied in 6 multiple-logistic regression models.

RESULTS

3632 catheters were studied. Incidences of colonization and bacteremia per 1000 days of catheterization were 17.56 and 3.93, respectively. Coagulase-negative staphyloccoci (CNS) were the most frequently isolated microorganisms. The colonization risk factors were: insertion site for all the microorganisms except fungi, catheterization time for CNS and fungi, hospitalization area, sex and age for CNS model, the existence of other infectious foci for Gram negative bacilli (GNB), S. aureus and other microorganisms, hypoalbuminemia for GNB model, and neoplasm for other microorganisms. The bacteremia risk factors were jugular insertion site, catheterization time greater than 10 days, catheter's hub colonization, and catheter colonization by gram-negative bacilli, fungi and S. aureus.

CONCLUSION

Risk factors for catheter colonization vary depending on the microorganism which colonizes the catheter.

Catheter-related infections: diagnosis and intravascular treatment

The diagnosis of catheter-related infections relies on the presence of clinical manifestations of infection and the evidence of colonization of the catheter tip by bacteria, mycobacteria or fungi. The reference method to confirm the latter requires the withdrawal of the catheter for culturing, which frequently turns out to be inconvenient, unnecessary and costly. New methods try to avoid these inconveniences and to assess the presence of tip colonization without withdrawal. One of these methods uses quantitative blood cultures with a jump (> or = 5) in colony counts between blood obtained from the catheter lumen and simultaneously from a peripheral vein. It has a high sensitivity (>80%) and specificity (94%-100%) but is cumbersome and requires both an easy backflow of blood in the catheter and the existence of bacteremia. Cytocentrifugation and acridine orange staining of blood withdrawn from an infected catheter lumen has a sensitivity and a specificity of over 90% for the diagnosis of tip colonization. "Superficial cultures" consist in the semiquantitative culture of the hub, of the skin surrounding the catheter entrance and of the first (1 cm) subcutaneous portion of the catheter after swabbing. Sensitivity of this method is >90% and specificity is >80%, and positive and negative predictive values for catheters (considering together those with and without clinical data of infection) are 66% and 97%, respectively. Endoluminal brushing has turned out to be an impractical and unreliable procedure, at least in our experience. New methods based on the speed of bacterial growth to detectable levels of microorganisms in conventional blood cultures are a new and interesting way of assessing catheter-related infections. Besides, as use of antimicrobial-coated catheters becomes more prevalent, the existing definitions of catheter colonization and catheter-related infection may need to be modified, because such coatings may lead to false-negative culture results. Many catheter infections, diagnosed without catheter withdrawal, can be handled nowadays with the so-called "antibiotic lock-in technique", which consists in locking the infected catheter lumen with a solution containing antibiotics. A high proportion of infected catheters, mainly those with coagulase-negative staphylococci, can be maintained in place and sterilized with this technique, including catheters in patients with therapeutic failure after receiving conventional intravenous antibiotic therapy. New diagnostic and therapeutic techniques may avoid the unnecessary withdrawal of thousands of efficient, difficult to replace and expensive intravascular lines.