Epidemiology and risk factors of 28-day mortality of hospital-acquired bloodstream infection in Turkish intensive care units: a prospective observational cohort study.

OBJECTIVES: To uncover clinical epidemiology, microbiological characteristics and outcome determinants of hospital-acquired bloodstream infections (HA-BSIs) in Turkish ICU patients. METHODS: The EUROBACT II was a prospective observational multicontinental cohort study. We performed a subanalysis of patients from 24 Turkish ICUs included in this study. Risk factors for mortality were identified using multivariable Cox frailty models. RESULTS: Of 547 patients, 58.7% were male with a median [IQR] age of 68 [55-78]. Most frequent sources of HA-BSIs were intravascular catheter [182, (33.3%)] and lower respiratory tract [175, (32.0%)]. Among isolated pathogens (n = 599), 67.1% were Gram-negative, 21.5% Gram-positive and 11.2% due to fungi. Carbapenem resistance was present in 90.4% of Acinetobacter spp., 53.1% of Klebsiella spp. and 48.8% of Pseudomonas spp. In monobacterial Gram-negative HA-BSIs (n = 329), SOFA score (aHR 1.20, 95% CI 1.14-1.27), carbapenem resistance (aHR 2.46, 95% CI 1.58-3.84), previous myocardial infarction (aHR 1.86, 95% CI 1.12-3.08), COVID-19 admission diagnosis (aHR 2.95, 95% CI 1.25-6.95) and not achieving source control (aHR 2.02, 95% CI 1.15-3.54) were associated with mortality. However, availability of clinical pharmacists (aHR 0.23, 95% CI 0.06-0.90) and source control (aHR 0.46, 95% CI 0.28-0.77) were associated with survival. In monobacterial Gram-positive HA-BSIs (n = 93), SOFA score (aHR 1.29, 95% CI 1.17-1.43) and age (aHR 1.05, 95% CI 1.03-1.08) were associated with mortality, whereas source control (aHR 0.41, 95% CI 0.20-0.87) was associated with survival. CONCLUSIONS: Considering high antimicrobial resistance rate, importance of source control and availability of clinical pharmacists, a multifaceted management programme should be adopted in Turkish ICUs.

Revealing the single-channel characteristics of OprD (OccAB1) porins from hospital strains of Acinetobacter baumannii.

Nowadays, reports of antimicrobial resistance (AMR) against many antibiotics are increasing because of their misapplication. With this rise, there is a serious decrease in the discovery and development of new types of antibiotics amid an increase in multi-drug resistance. Unfermented Acinetobacter baumannii from gram-negative bacteria, which is one of the main causes of nosocomial infections and multi-drug resistance, has 4 main kinds of antibiotic resistance mechanism: inactivating antibiotics by enzymes, reduced numbers of porins and changing of their target or cellular functions due to mutations, and efflux pumps. In this study, characterization of the possible mutations in OprD (OccAB1) porins from hospital strains of A. baumannii were investigated using single channel electrophysiology and compared with the standard OprD isolated from wild type ATCC 19,606. For this aim, 5 A. baumannii bacteria samples were obtained from patients infected with A. baumannii, after which OprD porins were isolated from these A. baumannii strains. OprD porins were then inserted in an artificial lipid bilayer and the current-voltage curves were obtained using electrical recordings through a pair of Ag/AgCl electrodes. We observed that each porin has a characteristic conductance and single channel recording, which then leads to differences in channel diameter. Finally, the single channel data have been compared with the gene sequences of each porin. It was interesting to find out that each porin isolated has a unique porin diameter and decreased anion selectivity compared to the wild type.

Hematologic Parameters as Predictors of Long-Term Mortality in Infective Endocarditis Patients.

BACKGROUND Infective endocarditis (IE) is an endothelial infection that is associated with high mortality and morbidity rates. Early and accurate risk prediction is important in patients with IE. Neutrophil-to-lymphocyte ratio (NLR), which is one of the hematological parameters that can be performed anywhere and is easily accessible, is a predictor of poor prognosis in many infectious and cardiovascular diseases. This study aimed to evaluate the association between laboratory parameters and 3-year mortality in 155 patients with infective endocarditis at a single center in Turkey. MATERIAL AND METHODS We retrospectively analyzed the clinical and echocardiographic data of 155 adult patients with definite IE according to the modified Duke Criteria, and we analyzed all laboratory results, such as hemoglobin, white blood cell, neutrophil, lymphocyte, platelet, platelet distribution width, NLR, urea, creatinine, albumin, procalcitonin, and blood culture results. RESULTS The median follow-up time was 341 days (range, 2-4003 days). The out-of-hospital mortality rate was 31.6%. Among the discharged patients (n=106), there were 46 non-survivors, with an out-of- hospital mortality rate of 43.4%. The overall mortality rate was 61.3%. During the follow-up, the 1-year mortality rate was 47.1% and the 3-year mortality rate was 54.8%. We detected significant differences in the admission values of NLR between the patients with and without 3-year mortality (P<0.001). CONCLUSIONS The NLR on admission to a tertiary center was independently associated with 3-year mortality in IE patients (P<0.001). NLR is a parameter that can be obtained from a simple, widely available and inexpensive hemagroma as a useful marker in predicting long-term mortality in IE.

Effects of vancomycin, daptomycin, and tigecycline on coagulase-negative staphylococcus biofilm and bacterial viability within biofilm: an in vitro biofilm model.

Bacteria may hide in a hydrated polysaccharide matrix known as a biofilm. The structure of the bacterial biofilm renders phagocytosis difficult and increases antibiotic resistance. We hypothesized that repeated doses of antibiotics have an effect on bacteria within the biofilm and that it could inhibit or eradicate biofilm formation. Two clinical biofilm-positive coagulase-negative staphylococcus isolates were evaluated. The effects of antibiotics on preformed and nascent biofilm and on bacterial eradication within the biofilm were determined using different doses of vancomycin, daptomycin, and tigecycline for different durations in an in vitro biofilm model. Vancomycin neither penetrated the biofilm nor had any microbicidal effect on bacteria within the biofilm. Daptomycin had a microbicidal effect on bacteria within the biofilm but had no effect on biofilm inhibition and eradication (independent from dose and treatment time). Tigecycline inhibited and eradicated biofilm formation and had a microbicidal effect on bacteria within the biofilm. In conclusion, (i) biofilm formation appeared to be a major barrier to vancomycin activity, (ii) daptomycin had an antimicrobial effect on the bacteria within the biofilm but not on the biofilm burden, and (iii) tigecycline had effects both on bacteria within the biofilm and on biofilm burden. Thus, both tigecycline and daptomycin might be promising candidates for the treatment of biofilm infections.

Missed Opportunities in HIV Testing in Turkiye: Implications for Late Diagnoses.

BACKGROUND: Late diagnosis of HIV infection is a major global problem. In Turkiye, only 41%-50% of people living with HIV are diagnosed, suggesting that many opportunities for HIV testing might be missed. SETTING: The aim of this study was to determine the missed testing opportunities for HIV in healthcare settings in Turkiye and the predictors for missed opportunities (MOs). METHODS: The study included patients with a new HIV diagnosis, presenting to care between January 2018 and December 2020. They were given a verbal questionnaire face to face, by a telephone call or an online meeting for visits to a health care setting within the year before their diagnosis. Electronic medical records were also examined. RESULTS: The sample included 198 patients with at least 1 visit to any health care setting, with a total of 1677 visits. Patients had an indication for HIV testing in 51.3% (861/1677) of the visits; an HIV test was not offered in 77.9% (671/861) and was considered a MO. The highest number of MOs was in emergency departments (59.8%) (180/301). The most common reason for visiting was constitutional symptoms and indicator conditions (55.4%) (929/1677). University graduates and those with a CD4+ T-cell count <200/mm 3 were more likely to have a MO. CONCLUSIONS: Many opportunities to diagnose HIV at an early stage are missed in health care settings in Turkiye. Considering the rapidly increasing number of new diagnoses in the last decade, urgent action needs to be taken.

Renal cyst infection caused by Brucella abortus.

A 49-year-old man with a medical history of polycystic kidney disease was presented to the emergency department with fever and left flank pain. Abdominal examination revealed an enlarged and painful left kidney. The C-reactive protein level was significantly high and the magnetic resonance imaging revealed areas of abnormal intensity and fluid-fluid levels in renal cysts. Brucella abortus was yielded from both blood and cyst fluid culture. Standard therapy (rifampicin plus doxycycline) of brucellosis was started, but the clinical and laboratory signs subsided after the addition of ciprofloxacin. There was no need for aspiration of infected cyst fluid. Hereby, according to the medical database search, we report that the first renal cyst infection caused by B. abortus was successfully treated with triple antibiotic therapy.

The seroprevalence of Crimean-Congo haemorrhagic fever among inhabitants living in the endemic regions of Western Anatolia.

BACKGROUND: In Turkey, Crimean-Congo haemorrhagic fever (CCHF) is seen particularly in the north-eastern part of Anatolia. Aydin was thought to be a non-endemic area, however the first case was reported from Aydin in 2006 and a total of 39 cases were reported between 2006 and 2010. METHODS: Four hundred and twenty-nine volunteers from 3 endemic regions of Aydin were enrolled in this study. We determined the IgG seropositivity against the virus by enzyme-linked immunosorbent assay (ELISA) method. RESULTS: IgG seropositivity in the study group was found to be 19.6% (n = 84). Chi-squared automatic interaction detector (CHAID) analysis was performed and a significant relationship between IgG seropositivity and tick-bite was found. The IgG seropositivity rate was 13% in cases without a history of tick-bite, while it was 41.1% in those with a tick-bite history (p < 0.001). In cases without a history of tick-bite (n = 339), the most important factor related to seropositivity was cattle-dealing. The seropositivity rate was higher in women than in men in the group dealing with cattle without a history of tick-bite (p = 0.013). In cases with a tick-bite history, the most important factor related to IgG seropositivity was age; the rate was 81% in cases younger than 34 y old, while it was 29% in cases older than 34 y. CONCLUSIONS: This study indicates that people suffering from the disease did not ask for any professional healthcare or that the healthcare providers could not diagnose these cases.

The diagnosis of diabetic foot osteomyelitis: examination findings and laboratory values.

BACKGROUND: This study aimed to demonstrate how much examination findings and laboratory values can be helpful in the diagnosis of osteomyelitis in patients with diabetic foot infections. MATERIAL/METHODS: Data of 46 consecutive inpatients prospectively followed up according to a specially designed "Diabetic Foot Follow-up Form" were analyzed. Following diagnostic interventions, clinical and laboratory findings of patients with and without a diagnosis of osteomyelitis were compared. In these patients with and without osteomyelitis confirmed by histopathology and/or microbiology and/or MRI the sensitivity and specificity of ESR (erythrocyte sedimentation rate) and wound size were also determined. RESULTS: There was no significant differences in the duration of diabetes or the existence of nephropathy or vascular disease, while the other findings (ESR, C-reactive protein, wound size, history of diabetic foot ulcer, and retinopathy) were significantly different. It is found that ESR > or =65 mm/h together with a wound size > or =2 cm2 had a sensitivity of 83%, specificity of 77%, positive predictive value of 80%, and negative predictive value of 81% in the diagnosis of osteomyelitis. CONCLUSIONS: This study demonstrated that simple clinical evaluation and laboratory findings without using expensive imaging methods may be important indicators of osteomyelitis.

The effects of ozone on bacterial growth and thiol-disulphide homeostasis in vascular graft infection caused by MRSA in rats.

PURPOSE:: To investigate the microbiological, inflammatory and oxidant effects of adjuvant ozone administration in experimental rat vascular graft infection model which has not been previously investigated. METHODS:: Forty adult Wistar rats were divided into Sham, Control, Vancomycin, Ozone, Vancomycin+Ozone groups. Grafts were inoculated with Methicillin-resistant Staphylococcus aureus (MRSA) strain and implanted subcutaneously. Rats were treated intraperitoneally with ozone and /or intramuscularly with vancomycin for 10 days. Grafts were evaluated by quantitative bacterial cultures. Blood samples were harvested for determination of thiol-disulphide and cytokine profiles. RESULTS:: There was no significant difference in bacterial counts between Control and Ozone Groups. In the Ozone Group median colony count was significantly higher than the Vancomycin and Vancomycin+Ozone Groups. Total thiol and disulphide levels increased and disulphide/native thiol and disulphide/total thiol ratios decreased in Ozone Group significantly. Albumin levels decreased significantly in Vancomycin and Vancomycin+Ozone Groups compared to the Sham Group. IL-1 and TNF-alpha levels significantly increased in infected rats. Decreased levels of VEGF due to infection reversed by ozone therapy in control and vancomycin groups. CONCLUSIONS:: We didn't observe any benefit of the agent on MRSA elimination in our model. Likewise, effects of ozone on thiol-disulphide homeostasis and inflammatory cytokines were contradictory.

Neuraminidase produces dose-dependent decrease of slime production and adherence of slime-forming, coagulase-negative staphylococci.

BACKGROUND: Slime is one of the important structures of certain bacterial strains involved in nonspecific adherence. This study was conducted to determine the role of neuraminidase on slime formation and adherence of slime-forming coagulase-negative staphylococci to inert surface. METHODS: Quantitative biofilm and qualitative bacterial adherence assays were performed with increasing concentrations of neuraminidase extracted from Clostridium perfringens-treated bacteria in polystyrene plates and polypropylene tubes. RESULTS: Slime production of slime-forming, coagulase-negative staphylococci was significantly decreased dose dependently at > or =100 mU/mL (p <0.001). Bacterial adherence to smooth surface was impeded at > or =100 mU/mL of neuraminidase treatment and adherence results were comparable with slime production assay results. CONCLUSIONS: Sialic acid may be a constituent molecule of slime and involved in bacterial adherence to inert surface. These results represent new insight into the mechanism of slime production and adherence of slime-forming, coagulase-negative staphylococci to inert surface.

Effect of preventive applications on prevalence of hepatitis B virus and hepatitis C virus infections in West Turkey.

OBJECTIVE: Hepatitis B virus (HBV) and hepatitis C virus (HCV) infections are community health problems in developing countries and the most common causative agents of chronic hepatitis, cirrhosis and hepatocellular carcinoma. This study investigates the prevalence and the effect of preventive applications on prevalence of HBV and HCV infections in blood donors. METHODS: Blood donors enrolled to the University and State Hospital Blood Banks in Aydin region of Turkey through the years 1993 to 2002 were retrospectively analyzed. Blood donors were investigated in 2 groups, Group I (1993-1997) and Group II (1998-2002) to compare the prevalence difference in 10-years period. Serum hepatitis B antigen (HbsAg) and anti-HCV were tested by commercially available enzyme-linked immunosorbent assay kits and anti-HCV positive results were confirmed by recombinant immune blot assays HCV test. RESULTS: The prevalence of HBV and HCV infections was determined as 1.5% and 0.19% over the period 1993-2002. Although, the prevalence of HBV infection declined significantly in Group II (1.17%) in comparison with Group I (2.27%) (p<0.0001), there was no significant difference in both groups regarding HCV infection (p=0.238). CONCLUSION: Preventive applications against blood transfusion related diseases succeed to decrease HBV infection significantly in West Turkey. Vaccination seems to be the most effective method to prevent hepatitis infection.

Hypochlorous Acid: an ideal wound care agent with powerful microbicidal, antibiofilm, and wound healing potency.

INTRODUCTION: Chronic wounds and the infections associated with them are responsible for a considerable escalation in morbidity and the cost of health care. Infection and cellular activation and the relation between cells are 2 critical factors in wound healing. Since chronic wounds offer ideal conditions for infection and biofilm production, good wound care strategies are critical for wound healing. Topical antiseptics in chronic wounds remain in widespread use today. These antiseptics are successful in microbial eradication, but their cytotoxcity is a controversial issue in wound healing. OBJECTIVE: The aim of this study was to investigate the effect of stabilized hypochlorous acid solution (HOCl) on killing rate, biofilm formation, antimicrobial activity within biofilm against frequently isolated microorganisms and migration rate of wounded fibroblasts and keratinocytes. MATERIALS AND METHODS: Minimal bactericidal concentration of stabilized HOCl solution for all standard microorganisms was 1/64 dilution and for clinical isolates it ranged from 1/32 to 1/64 dilutions. RESULTS: All microorganisms were killed within 0 minutes and accurate killing time was 12 seconds. The effective dose for biofilm impairment for standard microorganisms and clinical isolates ranged from 1/32 to 1/16. Microbicidal effects within the biofilm and antibiofilm concentration was the same for each microorganism. CONCLUSION: The stabilized HOCl solution had dose-dependent favorable effects on fibroblast and keratinocyte migration compared to povidone iodine and media alone. These features lead to a stabilized HOCl solution as an ideal wound care agent.

The effects of ozone on bacterial growth and thiol-disulphide homeostasis in vascular graft infection caused by MRSA in rats

Purpose: To investigate the microbiological, inflammatory and oxidant effects of adjuvant ozone administration in experimental rat vascular graft infection model which has not been previously investigated. Methods: Forty adult Wistar rats were divided into Sham, Control, Vancomycin, Ozone, Vancomycin+Ozone groups. Grafts were inoculated with Methicillin-resistant Staphylococcus aureus (MRSA) strain and implanted subcutaneously. Rats were treated intraperitoneally with ozone and /or intramuscularly with vancomycin for 10 days. Grafts were evaluated by quantitative bacterial cultures. Blood samples were harvested for determination of thiol-disulphide and cytokine profiles. Results: There was no significant difference in bacterial counts between Control and Ozone Groups. In the Ozone Group median colony count was significantly higher than the Vancomycin and Vancomycin+Ozone Groups. Total thiol and disulphide levels increased and disulphide/native thiol and disulphide/total thiol ratios decreased in Ozone Group significantly. Albumin levels decreased significantly in Vancomycin and Vancomycin+Ozone Groups compared to the Sham Group. IL-1 and TNF-alpha levels significantly increased in infected rats. Decreased levels of VEGF due to infection reversed by ozone therapy in control and vancomycin groups. Conclusions: We didn't observe any benefit of the agent on MRSA elimination in our model. Likewise, effects of ozone on thiol-disulphide homeostasis and inflammatory cytokines were contradictory.(AU)

The effects of ozone on bacterial growth and thiol-disulphide homeostasis in vascular graft infection caused by MRSA in rats

Abstract: Purpose: To investigate the microbiological, inflammatory and oxidant effects of adjuvant ozone administration in experimental rat vascular graft infection model which has not been previously investigated. Methods: Forty adult Wistar rats were divided into Sham, Control, Vancomycin, Ozone, Vancomycin+Ozone groups. Grafts were inoculated with Methicillin-resistant Staphylococcus aureus (MRSA) strain and implanted subcutaneously. Rats were treated intraperitoneally with ozone and /or intramuscularly with vancomycin for 10 days. Grafts were evaluated by quantitative bacterial cultures. Blood samples were harvested for determination of thiol-disulphide and cytokine profiles. Results: There was no significant difference in bacterial counts between Control and Ozone Groups. In the Ozone Group median colony count was significantly higher than the Vancomycin and Vancomycin+Ozone Groups. Total thiol and disulphide levels increased and disulphide/native thiol and disulphide/total thiol ratios decreased in Ozone Group significantly. Albumin levels decreased significantly in Vancomycin and Vancomycin+Ozone Groups compared to the Sham Group. IL-1 and TNF-alpha levels significantly increased in infected rats. Decreased levels of VEGF due to infection reversed by ozone therapy in control and vancomycin groups. Conclusions: We didn't observe any benefit of the agent on MRSA elimination in our model. Likewise, effects of ozone on thiol-disulphide homeostasis and inflammatory cytokines were contradictory.

Tetanus seroepidemiology and factors influencing immunity status among farmers of advanced age.

OBJECTIVES: Tetanus, which is a vaccine preventable disease, remains a significant health concern. The mortality is especially high in elderly and farming is a significant risk factor for the disease. This study evaluates the serological immunity of tetanus and the related factors, in a farmer population. METHODS: This cross-sectional study was carried out in a village located in the western part of Turkey. Volunteer farmers over the age of 50 were included in the study. The study group was determined by the systematic sampling method. IgG class tetanus antibody was measured in sera of each participant. A structured questionnaire evaluating the demographic characteristics was completed by the investigators. RESULTS: A total of 293 participants (55.3% female, 44.7% male) were recruited from March 2010 to June 2010. A serum protective tetanus antitoxin level (> 0.1 IU/ml) was detected in 99 out of 293 (33.9%) of participants. According to univariate analysis; advancing age, female gender, lower education, low monthly income, presence of chronic disease, absent or incomplete vaccination history or being unvaccinated in the last ten years were risk factors for insufficient tetanus immunity. After multiple logistic regression analysis, up-to-date vaccination, gender and age were the only factors that remained independently associated with immune status (p < 0.001). CONCLUSION: Farmers of advancing age are a population at risk for tetanus due to their work environment and their absent or incomplete immunization to the disease. Low rates of immunity detected highlight the importance to explore strategies in order to improve immunization status in this risky population.

Peri-operative antibiotic prophylaxis: adherence to guidelines and effects of educational intervention.

BACKGROUND: This study was aimed to determine the propriety of perioperative antimicrobial prophylaxis, to evaluate the effects of a training intervention on correction. METHODS: This prospective educational intervention study was performed on clean, clean-contaminated, and contaminated wounds in elective procedures. The accuracy of the antimicrobial prophylaxis was analyzed according to international guidelines. The outcome measures were appropriateness of prophylactic antibiotic indication, choice, dose and duration; and cost of inappropriate administration. RESULTS: Before the intervention, 312 procedures were recorded compared with 322 after the intervention. Total compliance rate decreased from 34.3% to 28.5% after the intervention, though insignificantly (p=0.59). Educational training intervention did not change the rate of inappropriate antibiotic choice statistically, and prolonged antibiotic use was significantly higher after the intervention (p=0.01). The positive impact of the intervention was observed in decreased "not indicated but administered" rate (p=0.009) and absence of procedures with "indicated but not administered" and "inappropriate antibiotic dose" which also decreased significantly (both p<0.001). The total cost of irrational antibiotic use was US$26,230.20. CONCLUSIONS: Although this educational intervention study achieved improvements in indications, choice, and dosing of surgical antimicrobial prophylaxis, it failed to improve prolonged use and total compliance rate, and to lower the costs sufficiently. It will probably provide better results by means of compulsory measures for surgeons to comply with available protocols and guidelines, as well as education programs, in order to change the antibiotic utility habits on surgical prophylaxis and to achieve accurate prophylactic administrations.

An outbreak of Crimean-Congo hemorrhagic fever in western Anatolia, Turkey.

OBJECTIVE: Sporadic Crimean-Congo hemorrhagic fever (CCHF) cases were first reported in Turkey in 2002, arising particularly in northeastern Anatolia. Epidemics have been reported in neighboring countries since the 1970s. With the increase in number of CCHF virus infected or suspected cases in the Aydin region of western Anatolia by 2006, we decided to focus attention on this disease. METHODS: Twenty-six patients with an acute febrile syndrome characterized by malaise, bleeding, leukopenia, and thrombocytopenia were admitted to various hospitals in Aydin between May 2007 and June 2008. CCHF diagnosis was established by measuring IgM in a blood sample and/or detecting viral genome by real-time polymerase chain reaction (real-time PCR) or by clinical findings of the disease, even if IgM was negative (real-time PCR was not performed). RESULTS: Twenty-five patients (22 of the patients with cases confirmed by laboratory findings) matched the criteria for CCHF defined by the European Network for Diagnostics of 'Imported' Viral Diseases (ENIVD); one patient did not match suspected-case criteria, however he was also included in the study as his blood sample was positive according to real-time PCR. The most common signs and symptoms encountered were fever, myalgia, nausea, and vomiting. The overall case-fatality rate was 5.5% (one patient) in 2007. Patients showed hemorrhagic manifestations (35%), while complete blood counts revealed thrombocytopenia and leukopenia in 17 patients (65%), and raised levels of aspartate aminotransferase (77%), alanine aminotransferase (77%), lactate dehydrogenase (69%), and creatinine phosphokinase (42%). CONCLUSIONS: To date, western Anatolia has been accepted as a non-endemic area for this disease, with only sporadic cases. These non-endemic CCHF cases in Aydin province of the Aegean region should alert other non-endemic regions of the world to be mindful of this disease.

Elimination of intraluminal colonization by antibiotic lock in catheters.

Antibiotic lock (AL) technique for catheter related infection encompasses the filling of a catheter lumen with high concentrations of antibiotics for hours. The goal of AL therapy is to decontaminate the intraluminal surface of the catheter. However the duration of antibiotic therapy is not established. An in vitro model was designed to establish the time needed to eliminate intraluminal microbial colonization and to evaluate the efficacy of vancomycin in comparison with teicoplanin by using laboratory AL model. Human plasma was instilled into the catheters to allow deposition of fibrin and other products on the catheter wall. After 48 hours, the catheters were drained and inoculated with bacteria in tryptic soy broth. The catheters were then drained and filled with either (a) vancomycin saline solution (VSS) lock (b) teicoplanin saline solution (TSS) lock or (c) saline solution (SS) as the control and then incubated for 12 hours. After 12 hours incubation all the catheter were drained and filled with human plasma. Instillation of human plasma and AL was alternated every 12 hours to simulate clinical conditions. For each day three catheters, locked with VSS, TSS and SS were cultured for colony count. Microbial counts were expressed as total colony-forming units per longitudinal centimeters of catheter surface. A significant decrease in intraluminal catheter colonization started as early as day 1. At the end of 7th day catheters treated with VSS and TSS lock were completely sterile. The decrease of intraluminal colonization was similar in catheters treated with VSS and TSS lock. Also the decrease of intraluminal colonization were similar in catheter colonized with slime forming S. epidermidis and nonslime-forming S. epidermidis.