Reduced colonization and infection with miconazole-rifampicin modified central venous catheters: a randomized controlled clinical trial.

Objective: Central venous catheters (CVC) are a major cause of nosocomial bloodstream infections. Catheters modified with miconazole and rifampicin that constantly and slowly release antimicrobial substances are assumed to be beneficial in reducing rates of colonization and catheter-related infections.

Design And Setting: Prospective controlled non-blinded randomized clinical trial in two German university hospitals.

[Special aspects of implant-associated infection in orthopedic surgery. From the pathophysiology to custom-tailored prevention strategies].

One of the most important risk factors in orthopedic surgery is implant-associated infection. Adhesion and colonization mediated implant infections are extremely resistant to antibiotics and host defences and frequently persist until the biomaterial or foreign body is removed, which is standard therapy. Tissue damage caused by surgery and foreign body implantation increases the susceptibility to infections, activates host defences and stimulates the generation of inflammatory mediators including radicals that are further aggravated by bacterial activity and toxins.

Human cervicofacial actinomycoses: microbiological data for 1997 cases.

Actinomycoses are sporadically occurring endogenous polymicrobial inflammatory processes, in which fermentative actinomycetes of the genera Actinomyces, Propionibacterium, or Bifidobacterium act as the principal pathogens. Difficulties in diagnosing the disease in a timely and reliable fashion have led clinicians and microbiologists to grossly underestimate its medical importance. Therefore, we evaluated microbiological and selected clinical data derived from 1997 culture-positive cases of human cervicofacial actinomycoses examined in our laboratories during 1972-1999.

Antiinfective and encrustation-inhibiting materials--myth and facts.

Catheters, urethral and ureteral stents and other urological implants are frequently affected by encrustration and infection due to their permanent contact with urine. Indwelling urinary catheters provide a haven for microorganisms and thus require extensive monitoring. Several surface modification techniques have been proposed to improve the performance of devices including the immobilization of biomolecules, the incorporation of hydrophilic grafts to reduce protein adsorption, the creation of hydrophobic surfaces, the creation of microdomains to regulate cellular and protein adhesion, new polymers and antimicrobial coatings.

Novel strategies to prevent catheter-associated infections in oncology patients.

Aggressive cytotoxic treatment of cancer contributes to the growing number of life-threatening infections. Vascular catheters create predominant risks for staphylococcal, enterococcal and candida blood stream infections. Although the contaminating microorganisms may be few in number, the altered host immune response in the presence of such implants as well as disease-associated immunosuppression implies that even small bacterial counts have to be regarded as highly virulent species.

[Prevention of infection with Streptococcus pneumoniae].

Streptococcus pneumoniae is the most common etiologic agent in outpatients pneumonia. Pneumococcal infections are often associated with high mortality risk in immunocompromised patients. An increasing resistance of Streptococcus pneumoniae to antibiotics is observed worldwide.

The antimicrobial efficacy of a new central venous catheter with long-term broad-spectrum activity.

Indwelling vascular catheters are a major cause of nosocomial sepsis. Prevention of colonization of polymeric surfaces by continuous release of bactericidal, highly biocompatible antimicrobials incorporated into polymers has been investigated as a promising new approach. An antimicrobial polyurethane catheter was investigated by HPLC and various antimicrobial assays.

"Difficult to treat infections" pharmacokinetic and pharmacodynamic factors--a review.

"Difficult to cure infections" are characterized by poor penetration of antibiotics into infected vegetations, altered metabolic state of bacteria within the vegetation, absence of adequate host defense/cellular response. These infections typically include endocarditis, urinary tract infections (infected urinary tract stones), abscesses, infected fibrin clots (septic thromboemboli, haematomas, catheter-related infections) and foreign body infections. Four main aspects are discussed for the influence on human therapy: 1.

Measurement of ultrasonic-induced chlorhexidine liberation: correlation of the activity of chlorhexidine-silver-sulfadiazine-impregnated catheters to agar roll technique and broth culture.

The diagnosis of intravascular catheter-related infections continues to be a challenge to both the clinician and the microbiologist. To assess the antiseptic effects of silver-sulfadiazine-chlorhexidine-impregnated central venous catheters (SSC) on catheter culture systems, segments of fresh antiseptic- and non antiseptic-impregnated catheters as well as extracted catheters following five days of immersion in PBS were sonicated. The chlorhexidine liberated from the catheter material by ultrasonication was measured by HPLC.

Antimicrobial substances and effects on sessile bacteria.

Biofilms occur in natural aquatic ecosystems and on surfaces of biomaterials. They are generally associated with clinical infections predominantly of prosthetic hip joints, heart valves and catheters. Sessile microorganisms may be intimately associated with each other and to solid substratum through binding to and inclusion into exopolymer matrices on biofilms.

Killing effects of antibiotics and two-fold antimicrobial combinations on proliferating and non growing staphylococci.

Antimicrobial agents are generally tested against bacteria in the log phase of multiplication to produce the maximal bactericidal effect. In case of foreign body infections, bacteria may multiply less optimally. We examined the effects of several classes of lipophilic antistaphylococcal agents to determine their antimicrobial activity towards coagulase-positive and coagulase-negative staphylococci during the non-growing and slowly growing phases.

Investigation of a rifampin, fusidic-acid and mupirocin releasing silicone catheter.

After strict hygienical measures have been exhausted the use of plastic materials with antibacterial activity may reduce catheter related-bacterial colonization. An antimicrobial silicone catheter was investigated by HPLC-measurement, SEM, antimicrobial assays and standard biocompatibility tests. The modified catheter was highly biocompatible and the antimicrobial leaching non-toxic.

Efficacy of silver-coated medical devices.

Silver coating of medical devices is believed to prevent device-associated infection. Several in-vitro and in-vivo studies, as well as clinical observations on silver-nylon, silver-intramedullary pins, silver oxide Foley catheters and silver-coated vascular prostheses have been performed during the past 30 years. Nevertheless, randomized clinical studies showing efficacy of such coated medical devices in high-risk patient populations are rare, have dealt with very small numbers of patients or are controversial.

Anti-infective catheters: novel strategies to prevent nosocomial infections in oncology.

Intravenous access contributes significantly to the therapeutical success and to the comfort of oncologic patients. The highest risk for bloodstream infections, however, is vascular catheter-mediated. In oncology high mortality is associated with Pseudomonas aeruginosa, Candida albicans and Staphylococcus aureus sepsis.

Actinobacillus actinomycetemcomitans in the human oral microflora.

In this paper, the frequency of the microaerophilic gram-negative bacterium Actinobacillus actinomycetemcomitans (Ac) which is a component of the normal human oral microflora was investigated. Ac could be cultivated from oral material (molar sulcus and/or mucous membrane of the cheek) from 55 out of 405 healthy adults examined. This overall Ac frequency of 13.

Adjuvant properties of killed Propionibacterium avidum KP-40 in vaccination of dogs against canine parvovirosis.

Immunomodulating and adjuvant properties of Propionibacterium avidum KP-40 (PA), a potent stimulator of the macrophage-monocyte system and inducer of endogenous interferon, were tested in healthy dogs and in dogs vaccinated against canine parvovirosis (CPV). A single subcutaneous injection of PA (0.5 mg/kg b.