To delineate the epidemiology of catheter-associated urinary tract infections (CAUTIs) and to better understand the value of urine cultures for evaluation of fever in the intensive care unit (ICU) setting

Two-year retrospective review (2012–2013)

A single tertiary center with 1,200 hospital beds and 158 adult ICU beds

ICU patients with a CAUTI event

The cohort was identified from a prospective infection prevention database. Charts were reviewed to characterize the patients. CAUTI rates and device utilization ratio (DUR) were calculated. Clinical outcomes were recorded.

A total of 105 CAUTIs were identified using the National Health and Safety Network (NHSN) definition. Fever was the primary indication for obtaining urine culture in 102 patients (97%). Of these 105 patients, 51 (51%) had an alternative infection to explain the fever, with pneumonia (55%) being the most common followed by bloodstream infection (22%). A total of 18 patients (18%) had fever due to noninfectious cause, and 32 patients (32%) had no alternative explanation. Of these, 66% received appropriate empiric antimicrobial therapy, but no targeted therapy changes were made based on urine culture results. The other 34% did not receive antimicrobial therapy at all. Only 6% of all CAUTIs resulted in blood cultures positive for the same organism within 2 days. The urinary tract was not definitely established as the source of bloodstream infection.

Urine cultures obtained for evaluation of fever form the basis for identification of CAUTIs in the ICU. However, most patients with CAUTIs are eventually found to have alternative explanations for fever. CAUTI is associated with a low complication rate.

Infect. Control Hosp. Epidemiol. 2015;36(11):1330–1334

To compare antimicrobial utilization data derived from pharmacy dispensing records and nursing administration record data by 2 commonly used units of measure.

Data from nursing administration records and pharmacy dispensing records were obtained for 32 medical wards. From nursing and pharmacy data, defined daily doses (DDD) were calculated, and from the nursing data, days of therapy were derived. Direct comparison of total antimicrobial use was performed by graphical analysis and linear regression. Slope of trend line was used to quantify the difference between pairs of measures. Bland-Altman plots were constructed to determine constant and proportional bias. At the level of individual agents, difference between pairs of measures was calculated and presented graphically and the average (95% CI) for the difference between measures was determined.

Nursing administration record–derived DDD were on average 23% lower than corresponding rates of pharmacy dispensing record–derived DDD. The difference between rates of utilization by days of therapy vs DDD from the same source (nursing) was relatively small. Results from analysis of different individual agents were highly variable with wide 95% CIs.

In our setting, we found clinically relevant differences in antimicrobial utilization associated with data from different sources. This outweighed the importance of the metric (DDD or days of therapy). However, measurement of use of individual agents was highly variable and sensitive to both metric unit and data sources.

Infect Control Hosp Epidemiol 2015;00(0): 1–7

Immunocompromised patients now benefit from a longer life expectancy due to advanced medical techniques, but they are also weakened by aggressive treatment approaches and are at high risk for invasive fungal disease. We determined risk factors associated with an outbreak of invasive filamentous fungal infection (IFFI) among hospitalized hemato-oncological patients.

A retrospective, matched, case-control study was conducted between January 1, 2009, and April 31, 2011, including 29 cases (6 proven, 8 probable, and 15 possible) of IFFI and 102 matched control patients hospitalized during the same time period. Control patients were identified from the hospital electronic database. Conditional logistic regression was performed to identify independent risk factors for IFFI.

Overall mortality associated with IFFI was 20.7% (8.0%–39.7%). Myelodysplastic syndrome was associated with a higher risk for IFFI compared to chronic hematological malignancies. After adjustment for major risk factors and confounders, >5 patient transfers outside the protected environment of the hematology ward increased the IFFI risk by 6.1-fold. The risk increased by 6.7-fold when transfers were performed during neutropenia.

This IFFI outbreak was characterized by a strong association with exposure to the unprotected environment outside the hematology ward during patient transfer. The independent associations of a high number of transfers with the presence of neutropenia suggest that affected patients were probably not sufficiently protected during transport in the corridors. Our study highlights that a heightened awareness of the need for preventive measures during the entire care process of at-risk patients should be promoted among healthcare workers.

Infect Control Hosp Epidemiol 2014;00(0): 1–9

To quantify the Hawthorne effect of hand hygiene performance among healthcare workers using direct observation.

Prospective observational study.

Intensive care unit, university hospital.

Direct observation of hand hygiene compliance over 48 audits of 2 hours each. Simultaneously, hand hygiene events (HHEs) were recorded using electronic alcohol-based handrub dispensers. Directly observed and electronically recorded HHEs during the 2 hours of direct observation were compared using Spearman correlations and Bland-Altman plots. To quantify the Hawthorne effect, we compared the number of electronically recorded HHEs during the direct observation periods with the re-scaled electronically recorded HHEs in the 6 remaining hours of the 8-hour working shift.

A total of 3,978 opportunities for hand hygiene were observed during the 96 hours of direct observation. Hand hygiene compliance was 51% (95% CI, 49%–53%). There was a strong positive correlation between directly observed compliance and electronically recorded HHEs (ρ=0.68 [95% CI, 0.49–0.81], P<.0001). In the 384 hours under surveillance, 4,180 HHEs were recorded by the electronic dispensers. Of those, 2,029 HHEs were recorded during the 96 hours in which direct observation was also performed, and 2,151 HHEs were performed in the remaining 288 hours of the same working shift that were not under direct observation. Healthcare workers performed 8 HHEs per hour when not under observation compared with 21 HHEs per hour during observation.

Directly and electronically observed HHEs were in agreement. We observed a marked influence of the Hawthorne effect on hand hygiene performance.

Infect Control Hosp Epidemiol 2015;36(8):957–962

To assess the effectiveness of infection control preparedness for human infection with influenza A H7N9 in Hong Kong.

A descriptive study of responses to the emergence of influenza A H7N9.

A university-affiliated teaching hospital.

Healthcare workers (HCWs) with unprotected exposure (not wearing N95 respirator during aerosol-generating procedure) to a patient with influenza A H7N9.

A bundle approach including active and enhanced surveillance, early airborne infection isolation, rapid molecular diagnostic testing, and extensive contact tracing for HCWs with unprotected exposure was implemented. Seventy HCWs with unprotected exposure to an index case were interviewed especially regarding their patient care activities.

From April 1, 2013, through May 31, 2014, a total of 126 (0.08%) of 163,456 admitted patients were tested for the H7 gene by reverse transcription-polymerase chain reaction per protocol. Two confirmed cases were identified. Seventy (53.8%) of 130 HCWs had unprotected exposure to an index case, whereas 41 (58.6%) and 58 (82.9%) of 70 HCWs wore surgical masks and practiced hand hygiene after patient care, respectively. Sixteen (22.9%) of 70 HCWs were involved in high-risk patient contacts. More HCWs with high-risk patient contacts received oseltamivir prophylaxis (P=0.088) and significantly more had paired sera collected for H7 antibody testing (P<0.001). Ten (14.3%) of 70 HCWs developed influenza-like illness during medical surveillance, but none had positive results by reverse transcription-polymerase chain reaction. Paired sera was available from 33 of 70 HCWs with unprotected exposure, and none showed seroconversion against H7N9.

Despite the delay in airborne precautions implementation, no patient-to-HCW transmission of influenza A H7N9 was demonstrated.

Infect Control Hosp Epidemiol 2015;36(1): 87–92

To predict the likelihood of hospital-onset Clostridium difficile infection (HO-CDI) based on patient clinical presentations at admission

Retrospective data analysis

Six US acute care hospitals

Adult inpatients

We used clinical data collected at the time of admission in electronic health record (EHR) systems to develop and validate a HO-CDI predictive model. The outcome measure was HO-CDI cases identified by a nonduplicate positive C. difficile toxin assay result with stool specimens collected >48 hours after inpatient admission. We fit a logistic regression model to predict the risk of HO-CDI. We validated the model using 1,000 bootstrap simulations.

Among 78,080 adult admissions, 323 HO-CDI cases were identified (ie, a rate of 4.1 per 1,000 admissions). The logistic regression model yielded 14 independent predictors, including hospital community onset CDI pressure, patient age ≥65, previous healthcare exposures, CDI in previous admission, admission to the intensive care unit, albumin ≤3 g/dL, creatinine >2.0 mg/dL, bands >32%, platelets ≤150 or >420 109/L, and white blood cell count >11,000 mm3. The model had a c-statistic of 0.78 (95% confidence interval [CI], 0.76–0.81) with good calibration. Among 79% of patients with risk scores of 0–7, 19 HO-CDIs occurred per 10,000 admissions; for patients with risk scores >20, 623 HO-CDIs occurred per 10,000 admissions (P<.0001).

Using clinical parameters available at the time of admission, this HO-CDI model demonstrated good predictive ability, and it may have utility as an early risk identification tool for HO-CDI preventive interventions and outcome comparisons.

Infect Control Hosp Epidemiol 2015;00(0):1–7

Estimates of the excess length of stay (LOS) attributable to healthcare-associated infections (HAIs) in which total LOS of patients with and without HAIs are biased because of failure to account for the timing of infection. Alternate methods that appropriately treat HAI as a time-varying exposure are multistate models and cohort studies, which match regarding the time of infection. We examined the magnitude of this time-dependent bias in published studies that compared different methodological approaches.

We conducted a systematic review of the published literature to identify studies that report attributable LOS estimates using both total LOS (time-fixed) methods and either multistate models or matching patients with and without HAIs using the timing of infection.

Of the 7 studies that compared time-fixed methods to multistate models, conventional methods resulted in estimates of the LOS to HAIs that were, on average, 9.4 days longer or 238% greater than those generated using multistate models. Of the 5 studies that compared time-fixed methods to matching on timing of infection, conventional methods resulted in estimates of the LOS to HAIs that were, on average, 12.6 days longer or 139% greater than those generated by matching on timing of infection.

Our results suggest that estimates of the attributable LOS due to HAIs depend heavily on the methods used to generate those estimates. Overestimation of this effect can lead to incorrect assumptions of the likely cost savings from HAI prevention measures.

Infect. Control Hosp. Epidemiol. 2015;36(9):1089–1094

To investigate whether operative factors are associated with risk of surgical site infection (SSI) after hernia repair.

Retrospective cohort study.

Commercially insured enrollees aged 6 months-64 years with International Classification of Diseases, Ninth Revision, Clinical Modification procedure or Current Procedural Terminology, fourth edition, codes for inguinal/femoral, umbilical, and incisional/ventral hernia repair procedures from January 1, 2004, through December 31, 2010.

SSIs within 90 days after hernia repair were identified by diagnosis codes. The χ2 and Fisher exact tests were used to compare SSI incidence by operative factors.

A total of 119,973 hernia repair procedures were analyzed. The incidence of SSI differed significantly by anatomic site, with rates of 0.45% (352/77,666) for inguinal/femoral, 1.16% (288/24,917) for umbilical, and 4.11% (715/17,390) for incisional/ventral hernia repair. Within anatomic sites, the incidence of SSI was significantly higher for open versus laparoscopic inguinal/femoral (0.48% [295/61,142] vs 0.34% [57/16,524], P=.020) and incisional/ventral (4.20% [701/16,699] vs 2.03% [14/691], P=.005) hernia repairs. The rate of SSI was higher following procedures with bowel obstruction/necrosis than procedures without obstruction/necrosis for open inguinal/femoral (0.89% [48/5,422] vs 0.44% [247/55,720], P<.001) and umbilical (1.57% [131/8,355] vs 0.95% [157/16,562], P<.001), but not incisional/ventral hernia repair (4.01% [224/5,585] vs 4.16% [491/11,805], P=.645).

The incidence of SSI was highest after open procedures, incisional/ventral repairs, and hernia repairs with bowel obstruction/necrosis. Stratification of hernia repair SSI rates by some operative factors may facilitate accurate comparison of SSI rates between facilities.

Infect Control Hosp Epidemiol 2014;00(0): 1–7

Methicillin-resistant Staphylococcus aureus (MRSA) is a worldwide issue associated with significant morbidity and mortality. Multiple infection control (IC) approaches have been tested to control its spread; however, the success of the majority of trials has been short-lived and many efforts have failed. We report the long-term success of MRSA control from a prospective observational study over 20 years.

University Hospital Basel is a large tertiary care center with a median bed capacity of 855 and 5 intensive care units (ICUs); currently, the facility has >32,000 admissions per year.

The IC program at the University Hospital Basel was created in 1993, after 2 MRSA outbreaks. The program has included strict contact precautions with single rooms for MRSA-colonized or -infected patients, targeted admission screening of high-risk patients and healthcare workers at risk for carriage, molecular typing of all MRSA strains and routine decolonization of MRSA carriers including healthcare workers. We used the incidence of MRSA bloodstream infections (BSIs) to assess the effectiveness of this program. All MRSA cases were prospectively classified using a standardized case report form in nosocomial and nonnosocomial cases, based on CDC definitions.

Between 1993 and 2012, 540,669 blood samples were cultured. The number of blood cultures increased from 865 per 10,000 patient days in 1993 to 1,568 per 10,000 patient days in 2012 (P<.001). We identified 1,268 episodes of S. aureus BSI from 1,204 patients. MRSA accounted for 34 episodes (2.7%) and 24 of these (1.9%) were nosocomial. MRSA BSI incidence varied between 0 and 0.27 per 10,000 patient days and remained stable with no significant variation throughout the study period (P=.882).

Long-term control of MRSA is feasible when a bundle of IC precautions is strictly enforced over time.

Infect Control Hosp Epidemiol 2015;00(0): 1–8

To assess the temporal trend of reported occupational blood and body fluid exposures (BBFE) in French healthcare facilities.

Retrospective follow-up of reported BBFE in French healthcare facilities on a voluntary basis from 2003 to 2012 with a focus on those enrolled every year from 2008 to 2012 (stable cohort 2008–12).

Reported BBFE incidence rate per 100 beds decreased from 7.5% in 2003 to 6.3% in 2012 (minus 16%). Percutaneous injuries were the most frequent reported BBFE (84.0% in 2003 and 79.1% in 2012). Compliance with glove use (59.1% in 2003 to 67.0% in 2012) and sharps-disposal container accessibility (68.1% in 2003 to 73.4% in 2012) have both increased. A significant drop in preventable BBFE was observed (48.3% in 2003 to 30.9% in 2012). Finally, the use of safety-engineered devices increased from 2008 to 2012.

Of the 415,209 hospital beds in France, 26,158 BBFE could have occurred in France in 2012, compared with 35,364 BBFE in 2003. Healthcare personnel safety has been sharply improved during the past 10 years in France.

Infect. Control Hosp. Epidemiol. 2015;36(8):963–968