Enhanced Biofilm Eradication and Reduced Cytotoxicity of a Novel Polygalacturonic and Caprylic Acid Wound Ointment Compared with Common Antiseptic Ointments.

Antiseptic wound ointments are widely used to treat dermal wounds that are microbially contaminated. Polygalacturonic acid (PG)+caprylic acid (CAP) is a novel combination that has been shown to eradicate biofilms. We developed a novel PG+CAP ointment and compared the biofilm eradication capability and cytotoxicity of PG+CAP with that of commercially available antiseptic wound ointments. We used a well-established biofilm model to quantitatively assess the eradication of organisms following exposure to the wound ointments for 2 hours. PG+CAP ointment completely eradicated Candida albicans, multidrug-resistant Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus biofilms, whereas MediHoney, polyhexamethylene biguanide (PHMB), and benzalkonium chloride (BZK) ointments failed to eradicate all biofilms within 2 hours. We assessed cytotoxicity by exposing L-929 fibroblasts to extracts of each ointment; Trypan blue exclusion was used to assess cell viability, and Alamar blue conversion was used to assess metabolic function. After exposure to PG+CAP and MediHoney, fibroblast viability was 96.23% and 95.23%, respectively (Trypan blue), and was comparable to untreated cells (98.77%). PHMB and BZK showed reduced viability (83.25% and 77.83%, respectively, p < 0.05). Metabolic activity results followed a similar pattern. Cytotoxicity of PG+CAP ointment towards erythrocytes was comparable to saline. PG+CAP ointment seems to be safe and can rapidly eradicate microbial biofilm; thus, PG+CAP ointment merits further in vivo testing as a potential antimicrobial wound ointment.

Neutropenic Enterocolitis: Clinical Features and Outcomes.

BACKGROUND: Patients undergoing chemotherapy are at risk for mucosal injury and neutropenia, which facilitate colonic mucosal invasion by the bowel flora and subsequent neutropenic enterocolitis, which has a poor prognosis. OBJECTIVE: This study aimed to assess the clinical features and outcomes of neutropenic enterocolitis in patients at a comprehensive cancer center. DESIGN: This is a retrospective cohort study. SETTING: The study was conducted at the University of Texas MD Anderson Cancer Center. PATIENTS: Neutropenic enterocolitis was defined by the presence of an absolute neutrophil count <1000/mm, compatible abdominal symptoms, and either mucosal thickening on abdominal imaging or mucosal injury on colon biopsy. Patients who had been diagnosed between 2010 and 2018 were included. MAIN OUTCOMES: Complication and survival rates were analyzed using logistic regression and Cox regression analyses, respectively. RESULTS: Of the 49,244 patients who had neutropenia during the study period, 134 (2.7%) were included. The median time from neutropenia onset to neutropenic enterocolitis was 2 days (interquartile range, 1-10 days). Neutropenic enterocolitis symptoms lasted for a median of 11 days (interquartile range, 6-22 days). Most patients received antibiotics (88%) and granulocyte colony-stimulating factor (68%). Complications included sepsis (11%), colonic perforation (2%), pneumatosis intestinalis (2%), and abscess formation (2%). The risks associated with complications included immunosuppressive therapy use within 1 month before neutropenic enterocolitis onset (OR, 3.92; 95% CI, 1.04-14.76) and delayed imaging (OR, 1.10; 95% CI, 1.03-1.17). Older age, severe neutropenia, prolonged neutropenia before and after neutropenic enterocolitis diagnosis, and other concomitant systemic infections were associated with lower survival rates. LIMITATIONS: The performance of this study at a single center and its retrospective nature are limitations of the study. CONCLUSION: The prompt diagnosis and management of neutropenic enterocolitis are critical to prevent complications. The use of granulocyte colony-stimulating factor can be beneficial to shorten the duration of neutropenia. See Video Abstract at http://links.lww.com/DCR/B116. ENTEROCOLITIS NEUTROPÉNICA: CARACTERÍSTICAS CLÍNICAS Y RESULTADOS: Los pacientes sometidos a quimioterapia, están en riesgo de lesión de la mucosa y neutropenia, lo que facilita la invasión de la mucosa colónica por la flora intestinal y la subsecuente enterocolitis neutropénica, con un mal pronóstico.Evaluar las características clínicas y los resultados de la enterocolitis neutropénica de pacientes en un centro integral de cáncer.Estudio de cohorte retrospectivo.El estudio se realizó en el MD Anderson Cancer Center de la Universidad de Texas.Se definió la enterocolitis neutropénica, como la presencia de un recuento absoluto de neutrófilos <1000 / mm3, con síntomas compatibles abdominales y engrosamiento de la mucosa en imagen abdominal o lesión de la mucosa en biopsia de colon. Se incluyeron pacientes diagnosticados entre 2010 y 2018.Se analizaron las tasas de complicaciones y supervivencia mediante análisis de regresión logística y regresión de Cox.De 49,244 pacientes que tuvieron neutropenia durante el período de estudio, 134 (2.7%) fueron incluidos. La media del tiempo desde el inicio de la neutropenia hasta la enterocolitis neutropénica, fue de 2 días (RIC, 1-10 días). Los síntomas de enterocolitis neutropénica duraron una media de 11 días (RIC, 6-22 días). La mayoría de los pacientes recibieron antibióticos (88%) y factor estimulante de colonias de granulocitos (68%). Las complicaciones incluyeron sepsis (11%), perforación colónica (2%), neumatosis intestinal (2%) y formación de abscesos (2%). Los riesgos asociados con las complicaciones incluyeron, uso de terapia inmunosupresora dentro de 1 mes antes del inicio de la enterocolitis neutropénica (razón de probabilidades 3.92; intervalo de confianza del 95% 1.04-14.76) y demora en la obtención de imágenes (razón de probabilidades 1.10; intervalo de confianza del 95% 1.03-1.17), edad avanzada, neutropenia grave, neutropenia prolongada antes y después del diagnóstico de enterocolitis neutropénica y de otras infecciones sistémicas concomitantes, se asociaron con bajas tasas de supervivencia.Centro único y estudio retrospectivo.El rápidodiagnóstico y manejo de la enterocolitis neutropénica, es crítico para prevenir complicaciones. El uso del factor estimulante de colonias de granulocitos puede ser beneficioso para acortar la duración de la neutropenia. Consulte Video Resumen en http://links.lww.com/DCR/B116.

Advances in the prevention and management of central-line-associated bloodstream infections: The role of chelator-based catheter locks.

The proper functioning of central lines is imperative for the management of patients with cancer or on hemodialysis. However, these lifelines can become infected and can malfunction.Chelators such as citrate and EDTA have been widely studied alone or in combination with other antimicrobial agents in catheter lock solutions to prevent catheter-related bloodstream infections and to maintain catheter patency. Given their anticoagulation, antiplatelet aggregation, antibiofilm, antimicrobial activity, safety profile, as well as their low cost, chelators have long been considered alternatives to heparin and a vital component of catheter lock solutions. In this review, we present a detailed summary of the properties of chelators and in vitro and in vivo studies of chelator-containing lock solutions.

International experience with minocycline, EDTA and ethanol lock for salvaging of central line associated bloodstream infections.

BACKGROUND: The use of long-term central venous catheters (CVCs) could lead to serious bloodstream infections. Removal of the infected CVC and reinsertion of a new CVC are not always feasible and alternative lock therapy may be considered. We conducted a multicenter trial to assess the efficacy and safety of the lock therapy. METHODS: Between October 2013 and August 2014, we prospectively enrolled 20 patients with catheter-related bloodstream infections (CRBSIs) or central line-associated bloodstream infections (CLABSIs) in our sister institutions in three countries including Brazil, Lebanon, and Japan. The 20 patients who received M-EDTA-EtOH lock therapy were compared to 24 control patients who had their CVCs removed and a new CVC inserted. RESULTS: Both groups had comparable clinical characteristics. In the lock therapy group, 95% of the patients had microbiological eradication within 96 h after starting lock therapy versus 83% of the patients in the control group (p = .36). In the lock group, the CVC was salvaged and retained for a median of 21 days (range 7-51) from the onset of bacteremia. CONCLUSION: Our study suggests that M-EDTA-EtOH lock therapy may be an effective intervention to salvage long-term CVCs in the setting of CLABSI/CRBSI and hemodialysis cancer patients with limited vascular access.

Successful Salvage of Central Venous Catheters in Patients with Catheter-Related or Central Line-Associated Bloodstream Infections by Using a Catheter Lock Solution Consisting of Minocycline, EDTA, and 25% Ethanol.

In cancer patients with long-term central venous catheters (CVC), removal and reinsertion of a new CVC at a different site might be difficult because of the unavailability of accessible vascular sites. In vitro and animal studies showed that a minocycline-EDTA-ethanol (M-EDTA-EtOH) lock solution may eradicate microbial organisms in biofilms, hence enabling the treatment of central line-associated bloodstream infections (CLABSI) while retaining the catheter in situ Between April 2013 and July 2014, we enrolled 30 patients with CLABSI in a prospective study and compared them to a historical group of 60 patients with CLABSI who had their CVC removed and a new CVC inserted. Each catheter lumen was locked with an M-EDTA-EtOH solution for 2 h administered once daily, for a total of 7 doses. Patients who received locks had clinical characteristics that were comparable to those of the control group. The times to fever resolution and microbiological eradication were similar in the two groups. Patients with the lock intervention received a shorter duration of systemic antibiotic therapy than that of the control patients (median, 11 days versus 16 days, respectively; P < 0.0001), and they were able to retain their CVCs for a median of 74 days after the onset of bacteremia. The M-EDTA-EtOH lock was associated with a significantly decreased rate of mechanical and infectious complications compared to that of the CVC removal/reinsertion group, who received a longer duration of systemic antimicrobial therapy. (This study has been registered at ClinicalTrials.gov under registration no. NCT01539343.).

Case-Control Study of Telavancin as an Alternative Treatment for Gram-Positive Bloodstream Infections in Patients with Cancer.

Gram-positive bacterial infections are an important cause of morbidity and death among cancer patients, despite current therapy. In this case-control study, we evaluated the clinical outcomes and safety of telavancin in cancer patients with uncomplicated Gram-positive bloodstream infections (BSIs). Between March 2011 and May 2013, we enrolled cancer patients with uncomplicated Gram-positive BSIs to receive intravenous telavancin therapy for at least 14 days for Staphylococcus aureus and 7 days for other Gram-positive cocci. Patients with baseline creatinine clearance (CLCR) values of >50 ml/min received 10 mg/kg/day of telavancin, and those with CLCR values between 30 and 49 ml/min received 7.5 mg/kg/day. Patients were compared with a retrospective cohort of 39 historical patients with Gram-positive BSIs, matched for underlying malignancy, infecting organism, and neutropenia status, who had been treated with vancomycin. A total of 78 patients were analyzed, with 39 in each group. The most common pathogen causing BSIs was S. aureus (51%), followed by alpha-hemolytic streptococci (23%), Enterococcus spp. (15%), coagulase-negative staphylococci (8%), and beta-hemolytic streptococci (3%). Sixty-two percent of patients had hematological malignancies, and 38% had solid tumors; 51% of the patients were neutropenic. The overall response rate determined by clinical outcome and microbiological eradication at 72 h following the initiation of therapy, in the absence of relapse, deep-seated infections, and/or infection-related death, was better with telavancin than with vancomycin (86% versus 61%; P = 0.013). Rates of drug-related adverse events were similar in the two groups (telavancin, 31%; vancomycin, 23%; P = 0.79), with similar rates of renal adverse events. Telavancin may provide a useful alternative to standard vancomycin therapy for Gram-positive BSIs in cancer patients. (This study has been registered at ClinicalTrials.gov under registration no. NCT01321879.).

Glyceryl trinitrate complements citrate and ethanol in a novel antimicrobial catheter lock solution to eradicate biofilm organisms.

Antimicrobial catheter lock therapy is practiced to prevent lumenal-sourced infections of central venous catheters. Citrate has been used clinically as an anticoagulant in heparin-free catheter locks. Ethanol has also been widely studied as an antimicrobial lock solution component. This study reports on the synergy of glyceryl trinitrate (GTN) with citrate and ethanol in rapidly eradicating methicillin-resistant Staphylococcus aureus, methicillin-resistant Staphylococcus epidermidis, Pseudomonas aeruginosa, and Candida albicans biofilms in an in vitro model for catheter biofilm colonization. GTN has a long history of intravenous use as a hypotensive agent. It is potentially attractive as a component of a catheter lock solution because its physiologic half-life is quite short and its metabolic pathways are known. A lock containing 7% citrate and 20% ethanol required 0.01% GTN to fully eradicate biofilms of all test organisms within 2 h in the model. This GTN concentration is below the levels where clinically significant hypotensive effects are expected.

Characteristics and outcomes of methicillin-resistant staphylococcus aureus bloodstream infections in patients with cancer treated with vancomycin: 9-year experience at a comprehensive cancer center.

BACKGROUND: Methicillin-resistant Staphylococcus aureus (MRSA) bloodstream infections (BSIs) can cause significant morbidity and mortality in patients with cancer. However, data on outcomes of patients treated with vancomycin are lacking. METHODS: We identified 223 patients with cancer who developed MRSA BSIs between January 2001 and June 2009 and were treated with vancomycin. Treatment failure was defined as death within 60 days of infection, persistent bacteremia ≥5 days, fever ≥4 days, recurrence or relapse, and secondary MRSA infection. RESULTS: The treatment failure rate was 52% (116 of 223 patients). These patients were more likely to have been hospitalized, been treated with steroids within the previous 3 months, developed acute respiratory distress syndrome, required mechanical ventilation, required intensive care unit care, and community-onset infections (all p < .05). Risk factors for MRSA-associated mortality (27 of 223 patients; 12%) included hematologic malignancy and hematopoietic stem cell transplantation, community-onset infection, secondary BSI, MRSA with minimum inhibitory concentration (MIC) ≥2.0 µg/mL, mechanical ventilation, and a late switch to an alternative therapy (≥4 days after treatment failure; all p < .05). On multivariate analysis, mechanical ventilation and recent hospitalization were identified as independent predictors of vancomycin failure, and community-onset infection, secondary BSIs, and MIC ≥2 µg/mL were identified as significant predictors of MRSA-associated mortality. CONCLUSIONS: We found a high treatment failure rate for vancomycin in patients with cancer and MRSA BSIs, as well as a higher mortality. A vancomycin MIC ≥2 µg/mL was an independent predictor of MRSA-associated mortality. An early switch to an alternative therapy at the earliest sign of failure may improve outcome.

Colistin is effective in treatment of infections caused by multidrug-resistant Pseudomonas aeruginosa in cancer patients.

The increasing incidence of infections caused by multidrug-resistant Pseudomonas aeruginosa is a worldwide health problem. Because no new antipseudomonal agents are expected to be available in the near future, we evaluated the safety and efficacy of colistin, an old drug with bactericidal activity against this organism. We collected clinical and demographic data on 95 cancer patients diagnosed with infections caused by multidrug-resistant P. aeruginosa between January 2001 and January 2004 and treated with either colistin (colistin group) or at least one active antipseudomonal agent (a beta-lactam antibiotic or a quinolone) (control group). We compared the results obtained for both groups. Thirty-one patients had been treated with colistin and 64 had been treated with an antipseudomonal non-colistin-containing regimen. Compared with the control group, patients in the colistin group had a lower median age (52 and 62 years, respectively; P = 0.012) but were more likely to have had nosocomial infections (87% and 64%, respectively; P = 0.02). Twenty-five patients (81%) in the colistin group and 40 patients (63%) in the control group had an APACHE II score of >15 (P = 0.074). The overall clinical response rates were 52% in the colistin group and 31% in the control group (P = 0.055). Multiple logistic regression analysis showed that those patients treated with colistin were 2.9 times (95% confidence interval, 1.1 to 7.6 times) more likely than those in the control group to experience a clinical response to therapy (P = 0.026). Colistin therapy was at least as effective and as safe a beta-lactam antibiotic or a quinolone in the treatment of infections caused by multidrug-resistant P. aeruginosa and, hence, may be a useful or preferred alternative therapy for this infection in cancer patients.

Orthopaedic metal devices coated with a novel antiseptic dye for the prevention of bacterial infections.

Gendine is a novel antiseptic dye with broad-spectrum antimicrobial activity that may be used to coat plastics and metal devices. Our objective was to determine the efficacy of gendine-coated orthopaedic metal devices in preventing methicillin-resistant Staphylococcus aureus (MRSA) colonisation. Stainless steel and titanium Schanz rods were coated with gendine. The zone of inhibition (ZoI) around the rods with and without gamma-irradiation was determined by a modified Kirby-Bauer method. A previously published bioprosthetic biofilm colonisation model, modified Kuhn's method, was used to determine the adherence of MRSA to coated and uncoated rods, with and without irradiation, after insertion into bovine bone and after 3 months shelf life followed by 2 weeks of immersion in serum. The gendine-coated Schanz metal rods showed a net ZoI of 16 mm against MRSA before and after irradiation. Gendine-coated rods showed no biofilm formation (0 colony-forming units (CFU)), which was a significant reduction (P<0.001) compared with uncoated controls (>5000 CFU). Coated rods exposed to high-dose gamma-irradiation and coated rods drilled into bone also showed significant efficacy (P<0.001) in preventing biofilm adherence. After 2 weeks, gendine-coated rods maintained significant durability (P<0.01), resulting in 90% reduction in MRSA biofilm adherence compared with uncoated control rods. Results indicate that gendine-coated metal rods are highly efficacious in the prevention of MRSA biofilm.

EDTA as an adjunct antifungal agent for invasive pulmonary aspergillosis in a rodent model.

Rats immunosuppressed by the administration of cyclophosphamide and cortisone acetate and then infected with Aspergillus fumigatus were treated with an antifungal drug, EDTA, or a combination of one of the antifungal agents, amphotericin B lipid complex (ABLC; 5 mg/kg of body weight/day for 7 days), and EDTA (30 mg/kg/day for 7 days). The mortality rate was reduced, the duration of survival was increased, fewer A. fumigatus organisms were recovered from the lungs, and less-severe lung lesions were seen histopathologically in the rats receiving the combination treatment than in the rats receiving either an antifungal agent or EDTA alone. Further studies regarding the mechanisms of EDTA and its interactions with ABLC are warranted, and further studies are needed to more fully examine the safety, tolerance, and optimal dosing of EDTA in the treatment of this and other fungal infections.

Posaconazole: a broad-spectrum triazole antifungal.

Posaconazale is a new triazole drug being investigated in phase III clinical trials for the treatment and prevention of invasive fungal infections. In-vitro and in-vivo studies showed that posaconazole has broad-spectrum activity against most Candida species, Cryptococcus neoformans, Aspergillus species, Fusarium species, zygomycetes, and endemic fungi. Posaconazole is given orally two to four times daily. This triazole is widely distributed in the body, metabolised mainly by the liver, and is well tolerated, even in long-term courses. Adverse events are generally mild and include headache and gastrointestinal complaints. Posaconazole has shown promising clinical efficacy against life-threatening fungal infections that are often refractory to the currently available antifungal therapies-eg, invasive aspergillosis, fusariosis, and the emerging zygomycosis.

Prospective, randomized study comparing quinupristin-dalfopristin with linezolid in the treatment of vancomycin-resistant Enterococcus faecium infections.

OBJECTIVES: Quinupristin-dalfopristin and linezolid have been shown to be efficacious in the treatment of vancomycin-resistant Enterococcus faecium (VREF) infections. However, the two antibiotics have not been compared in terms of safety and efficacy in a prospective randomized study. The objective of this study was to compare the safety and efficacy of the two drugs in the treatment of VREF infections in cancer patients. PATIENTS AND METHODS: Forty cancer patients with VREF infection were randomized to receive linezolid 600 mg every 12 h or quinupristin-dalfopristin 7.5 mg/kg every 8 h. All patients were followed up for 30 days after discontinuation of study drugs. RESULTS: Linezolid and quinupristin-dalfopristin had comparable clinical responses (58% and 43%, respectively, P = 0.6). Myalgias and/or arthralgias occurred at a frequency of 33% in patients who received quinupristin-dalfopristin, but were not observed in the linezolid group (P = 0.03). In contrast, drug-related thrombocytopenia occurred in 11% of patients who received linezolid, but was not observed in the quinupristin-dalfopristin group (P = 0.2). CONCLUSION: In cancer patients, quinupristin-dalfopristin treatment is associated with a relatively high frequency of myalgias/arthralgias; however, profound thrombocytopenia might limit the choice of linezolid in a subpopulation of cancer patients.

In vitro and ex vivo activities of minocycline and EDTA against microorganisms embedded in biofilm on catheter surfaces.

Minocycline-EDTA (M-EDTA) flush solution has been shown to prevent catheter-related infection and colonization in a rabbit model and in hemodialysis patients. We undertook this study in order to determine the activities of M-EDTA against organisms embedded in fresh biofilm (in vitro) and mature biofilm (ex vivo). For the experiment with the in vitro model, a modified Robbin's device (MRD) was used whereby 25 catheter segments were flushed for 18 h with 10(6) CFU of biofilm-producing Staphylococcus epidermidis, Staphylococcus aureus, and Candida albicans per ml. Subsequently, each of the catheter segments was incubated in one of the following solutions: (i) streptokinase, (ii) heparin, (iii) broth alone, (iv) vancomycin, (v) vancomycin-heparin, (vi) EDTA, (vii) minocycline (high-dose alternating with low-dose), or (viii) M-EDTA (low-dose minocycline alternating with high-dose minocycline were used to study the additive and synergistic activities of M-EDTA). All segments were cultured quantitatively by scrape sonication. For the experiment with the ex vivo model, 54 catheter tip segments removed from patients and colonized with bacterial organisms by roll plate were longitudinally cut into two equal segments and exposed to either saline, heparin, EDTA, or M-EDTA (with high-dose minocycline). Subsequently, all segments were examined by confocal laser electron microscopy. In the in vitro MRD model, M-EDTA (with a low concentration of minocycline) was significantly more effective than any other agent in reducing colonization of S. epidermidis, S. aureus, and C. albicans (P < 0.01). M-EDTA (with a high concentration of minocycline) eradicated all staphylococcal and C. albicans organisms embedded in the biofilm. In the ex vivo model, M-EDTA (with a high concentration of minocycline) reduced bacterial colonization more frequently than EDTA or heparin (P < 0.01). We concluded that M-EDTA is highly active in eradicating microorganisms embedded in fresh and mature biofilm adhering to catheter surfaces.

Minocycline-ethylenediaminetetraacetate lock solution for the prevention of implantable port infections in children with cancer.

In this prospective cohort study, minocycline-ethylenediaminetetraacetate (M-EDTA) was used as a lock solution in indwelling ports inserted in 14 children with cancer. No port infections, thrombotic events, or other adverse events were observed, compared with 10 port infections that occurred in 48 control patients whose ports were flushed with heparin. M-EDTA is a promising lock solution in long-term catheters.

Efficacy of minocycline and EDTA lock solution in preventing catheter-related bacteremia, septic phlebitis, and endocarditis in rabbits.

To determine the efficacy of antibiotic catheter lock solution in preventing catheter-related infections, silicone catheters were tunneled and inserted into the jugular veins of 18 rabbits. The catheters were challenged with an intraluminal injection of 10(5) CFU of slime-producing Staphylococcus epidermidis in 0.1 ml of water. The catheters were maintained on heparin (100 IU/ml) flush for the first 3 days. On day 3, quantitative blood samples for culture were obtained from the catheters and ear veins, which documented catheter-related bacteremia, and the rabbits were randomized to have their catheters flushed as follows: five animals were continued on heparin (100 IU/ml), five animals received vancomycin (3 mg/ml) with heparin (100 IU/ml), and eight animals received 3 mg of minocycline per ml with 30 mg of EDTA per ml (M-EDTA). All animals were killed at day 7. Blood, catheters, jugular veins, and heart valves were cultured quantitatively. Animals maintained on heparin developed catheter-related colonization, bacteremia, septic phlebitis, and endocarditis. Vancomycin-heparin partially prevented catheter colonization, bacteremia, and phlebitis (P = 0.2). M-EDTA completely prevented catheter colonization, catheter-related bacteremia, and phlebitis in all of the animals (P < 0.01). Tricuspid endocarditis was equally prevented by vancomycin-heparin and M-EDTA (P < or = 0.06). In conclusion, the M-EDTA catheter flush solution was highly efficacious in preventing catheter-related colonization, bacteremia, septic phlebitis, and endocarditis in rabbits.