To screen copper and noncopper paints for their bactericidal effectiveness in rendering surfaces self-disinfecting.

Tested paints were applied to glass coverslips, cured, inoculated with test organisms (Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and Enterococcus faecalis), and dried. After 0, 24, or 48 hours, surviving organisms were eluted and enumerated, and counts compared with those obtained from inoculated control (unpainted) coverslips for the corresponding time periods. Copper elution from select copper paints was quantified by complete immersion of coated coverslips followed by spectroscopic analysis to infer a threshold relationship between kill and copper release.

Nearly all of the tested copper paints were capable of reducing organism counts to negligible levels within 24 hours. Exterior latex paints supplemented with a fungicide were similarly efficacious. Standard interior latex paint reduced bacterial counts to nearly zero within 24 hours for E coli and P aeruginosa, and to zero within 48 hours for E faecalis. However, substantial survival of S aureus occurred (up to 4 logs at 24 hours). Chi-squared analysis of elution and cidal data indicated that lethality was dependent on copper release in excess of 32 μg.

The data support presumptive bactericidal claims for several copper and noncopper paints. Despite controversy over environment-based contagion, such paints could be used to render surfaces self-disinfecting in strategic locations where environmental causation of nosocomial infections is suspected.

To describe the incidence and types of first Hickman catheter-related infection (HCRI) in cancer patients and to identify indicators for catheter removal.

Retrospective cohort study.

A regional, tertiary, referral cancer center and its supportive care university teaching hospital.

A retrospective review was conducted of 316 consecutive adult oncology patients who underwent Hickman catheter placement from 1986 to 1990 at a regional oncology center. HCRI was determined on the basis of clinical information incriminating the Hickman catheter as the source of infection. Patient characteristics and data about HCRIs (exit site cellulitis, tunnel infection with concomitant exit site cellulitis, bloodstream infection, and exit site cellulitis with bloodstream infection) were abstracted from patient medical records. Subsequently, univariate and multivariate analyses for the risk of HCRI and catheter removal were completed.

The incidence of first HCRI was 5.98 infections per 1,000 catheter days. Overall, 156 (49%) of 316 patients developed their first HCRI prior to catheter removal. The median time to HCRI was 90 days. Male gender (P= .0004) and hematologic malignancy (P= .0001) emerged as significant risk factors for HCRI in the univariate analysis. A Cox model verified that male gender (P=.02) and hematologic malignancy (P= .004) were associated with an enhanced risk of HCRI. There were 35 exit site infections (23%), three infections of the tunnel and the exit site (2%)) 80 bloodstream infections (51%), and another 38 bloodstream infections with concomitant exit site infections (24%). The incidence of bloodstream infection was 3.05 per 1,000 catheter days. Gram-positive pathogens outnumbered gram-negatives and fungi, with Staphylococcusepidermidis being most common. Fifty (32%) of 156 HCRIs resulted in catheter removal. Predictors of Hickman catheter removal in the univariate analysis were bloodstream infection (P= .046) and pathogen type (P= .006). Multiple regression analysis suggested that having a gram-negative (P= .014) or fungal (P= .057) pathogen was the most important factor for catheter removal.

These data suggest that first HCRIs occur more commonly in male patients with hematologic malignancies than in patients with solid tumors. The removal of Hickman catheters in oncology patients probably is predicated on the causative pathogen, but further investigations are necessary to delineate this issue.

To review and summarize the status of diagnosis, epidemiology, infection control, and treatment of Clostridium difficile -associated disease (CDAD).

A case definition of CDAD should include the presence of symptoms (usually diarrhea) and at least one of the following positive tests: endoscopy revealing pseudomembranes, stool cytotoxicity test for toxin B, stool enzyme immunoassay for toxin A or B, or stool culture for C difficile (preferably with confirmation of organism toxicity if a direct stool toxin test is negative or not done). Testing of asymptomatic patients, including those who are asymptomatic after treatment, is not recommended other than for epidemiologic purposes. Lower gastrointestinal endoscopy is the only diagnostic test for pseudomembranous colitis, but it is expensive, invasive, and insensitive (51% to 55%) for the diagnosis of CDAD. Stool culture is the most sensitive laboratory test currently in clinical use, but it is not as specific as the cell cytotoxicity assay.

C difficile is the most frequently identified cause of nosocomial diarrhea. The majority of C difficile infections are acquired nosocomially, and most patients remain asymptomatic following acquisition. Antimicrobial exposure is the greatest risk factor for patients, especially clindamycin, cephalosporins, and penicillins, although virtually every antimicrobial has been implicated. Cases of CDAD unassociated with prior antimicrobial or antineoplastic use are very rare. Hands of personnel, as well as a variety of environmental sites within institutions, have been found to be contaminated with C difficile, which can persist as spores for many months. Contaminated commodes, bathing tubs, and electronic thermometers have been implicated as sources of C difficile. Symptomatic and asymptomatic infected patients are the major reservoirs and sources for environmental contamination. Both genotypic and phenotypic typing systems for C difficile are available and have enhanced epidemiologic investigation greatly.

Successful infection control measures designed to prevent horizontal transmission include the use of gloves in handling body substances and replacement of electronic thermometers with disposable devices. Isolation, cohorting, handwashing, environmental disinfection, and treatment of asymptomatic carriers are recommended practices for which convincing data of efficacy are not available. The most successful control measure directed at reduction in symptomatic disease has been antimicrobial restriction.

Treatment of symptomatic (but not asymptomatic) patients with metronidazole or vancomycin for 10 days is effective; metronidazole may be preferred to reduce risk of vancomycin resistance among other organisms in hospitals. Recurrence of symptoms occurs in 7% to 20% of patients and is due to both relapse and reinfection. Over 90% of first recurrences can be treated successfully in the same manner as initial cases. Combination treatment with vancomycin plus rifampin or the addition orally of the yeast Saccharomyces boulardii to vancomycin or metronidazole treatment has been shown to prevent subsequent diarrhea in patients with recurrent disease.