To determine whether use of contact precautions on hospital ward patients is associated with patient adverse events

Individually matched prospective cohort study

The University of Maryland Medical Center, a tertiary care hospital in Baltimore, Maryland

A total of 296 medical or surgical inpatients admitted to non–intensive care unit hospital wards were enrolled at admission from January to November 2010. Patients on contact precautions were individually matched by hospital unit after an initial 3-day length of stay to patients not on contact precautions. Adverse events were detected by physician chart review and categorized as noninfectious, preventable and severe noninfectious, and infectious adverse events during the patient’s stay using the standardized Institute for Healthcare Improvement’s Global Trigger Tool.

The cohort of 148 patients on contact precautions at admission was matched with a cohort of 148 patients not on contact precautions. Of the total 296 subjects, 104 (35.1%) experienced at least 1 adverse event during their hospital stay. Contact precautions were associated with fewer noninfectious adverse events (rate ratio [RtR], 0.70; 95% confidence interval [CI], 0.51–0.95; P=.02) and although not statistically significant, with fewer severe adverse events (RtR, 0.69; 95% CI, 0.46–1.03; P=.07). Preventable adverse events did not significantly differ between patients on contact precautions and patients not on contact precautions (RtR, 0.85; 95% CI, 0.59–1.24; P=.41).

Hospital ward patients on contact precautions were less likely to experience noninfectious adverse events during their hospital stay than patients not on contact precautions.

Infect. Control Hosp. Epidemiol. 2015;36(11):1268–1274

To estimate the frequency of methicillin-resistant Staphylococcus aureus (MRSA) transmission to gowns and gloves worn by healthcare workers (HCWs) interacting with nursing home residents to better inform infection prevention policies in this setting

Observational study

Participants were recruited from 13 community-based nursing homes in Maryland and Michigan

Residents and HCWs from these nursing homes

Residents were cultured for MRSA at the anterior nares and perianal or perineal skin. HCWs wore gowns and gloves during usual care activities. At the end of each activity, a research coordinator swabbed the HCW’s gown and gloves.

A total of 403 residents were enrolled; 113 were MRSA colonized. Glove contamination was higher than gown contamination (24% vs 14% of 954 interactions; P<.01). Transmission varied greatly by type of care from 0% to 24% for gowns and from 8% to 37% for gloves. We identified high-risk care activities: dressing, transferring, providing hygiene, changing linens, and toileting the resident (OR >1.0; P<.05). We also identified low-risk care activities: giving medications and performing glucose monitoring (OR<1.0; P<.05). Residents with chronic skin breakdown had significantly higher rates of gown and glove contamination.

MRSA transmission from MRSA-positive residents to HCW gown and gloves is substantial; high-contact activities of daily living confer the highest risk. These activities do not involve overt contact with body fluids, skin breakdown, or mucous membranes, which suggests the need to modify current standards of care involving the use of gowns and gloves in the nursing home setting.

Infect. Control Hosp. Epidemiol. 2015;36(9):1050–1057

To develop and validate an algorithm to identify and classify noninvasive infections due to Staphylococcus aureus by using positive clinical culture results and administrative data.

Retrospective cohort study.

Veterans Affairs Maryland Health Care System.

Data were collected retrospectively on all S. aureus clinical culture results from samples obtained from nonsterile body sites during October 1998 through September 2008 and associated administrative claims records. An algorithm was developed to identify noninvasive infections on the basis of a unique S. aureus-positive culture result from a nonsterile site sample with a matching International Classification of Diseases, Ninth Revision (ICD-9-CM), code for infection at time of sampling. Medical records of a subset of cases were reviewed to find the proportion of true noninvasive infections (cases that met the Centers for Disease Control and Prevention National Healthcare Safety Network [NHSN] definition of infection). Positive predictive value (PPV) and negative predictive value (NPV) were calculated for all infections and according to body site of infection.

We identified 4,621 unique S. aureus-positive culture results, of which 2,816 (60.9%) results met our algorithm definition of noninvasive S. aureus infection and 1,805 (39.1%) results lacked a matching ICD-9-CM code. Among 96 cases that met our algorithm criteria for noninvasive S. aureus infection, 76 also met the NHSN criteria (PPV, 79.2% [95% confidence interval, 70.0%–86.1%]). Among 98 cases that failed to meet the algorithm criteria, 80 did not meet the NHSN criteria (NPV, 81.6% [95% confidence interval, 72.8%–88.0%]). The PPV of all culture results was 55.4%. The algorithm was most predictive for skin and soft-tissue infections and bone and joint infections.

When culture-based surveillance methods are used, the addition of administrative ICD-9-CM codes for infection can increase the PPV of true noninvasive S. aureus infection over the use of positive culture results alone.