Approaches to the detection of Clostridioides difficile in the healthcare environment

A comparison of culture methods and polymerase chain reaction in detecting Clostridioides difficile from hospital surfaces

Introduction. Environmental surveillance for Clostridioides difficile is challenging. There are no internationally agreed recommendations on which method should be used when environmental surveillance is undertaken.Aim. To compare the detection of C. difficile by RT-PCR to culture-based methods and to determine which is more sensitive and specific in the clinical environment.Methods. Forty-four near-patient areas of C. difficile-positive patients were sampled using contact plates and moistened flocked swabs.Results. Detection using moistened flocked swabs followed by RT-PCR or culture detected more C. difficile than contact plates. The sensitivity and specificity of a RT-PCR assay for tcdB compared to the culture methods was 76 and 91 %, respectively.Conclusion. Despite the lower sensitivity and specificity, RT-PCR could potentially offer a more rapid and practical alternative.

Assessment of Federal Value-Based Incentive Programs and In-Hospital Clostridioides difficile Infection Rates

IMPORTANCE

Health care facility-onset Clostridioides difficile infection (HO-CDI) rates reported to the US Centers for Disease Control and Prevention's National Healthcare Safety Network (NHSN) became a target quality metric for 2 Centers for Medicare & Medicaid Services (CMS) value-based incentive programs (VBIPs) in October 2016. The association of VBIPs with HO-CDI rates is unknown.

OBJECTIVE

To examine the association between VBIP implementation and HO-CDI rates.

DESIGN, SETTING, AND PARTICIPANTS

This interrupted time series study evaluated HO-CDI rates among adults hospitalized from January 2013 to March 2019 at 265 acute-care hospitals.

INTERVENTIONS

Implementation of VBIPs in October 2016.

MAIN OUTCOMES AND MEASURES

Quarterly rates of HO-CDI per 10 000 patient-days, as reported to NHSN by participating hospitals, were evaluated. Generalized estimating equations were used to fit negative binomial regression models to estimate immediate program effect size (ie, level change) and changes in the slope of HO-CDI rates, controlling for each hospital's predominant method of CDI testing (ie, nucleic acid amplification test [NAAT], enzyme immunoassay [EIA] for toxin, or other testing methods).

RESULTS

The study cohort included 24 332 938 admissions, 109 371 136 patient-days, and 74 681 HO-CDI events at 265 hospitals (145 [55%] with 100-399 beds; 205 [77%] not-for-profit hospitals; 185 [70%] teaching hospitals; 229 [86%] in metropolitan areas). Compared with EIA, rates of HO-CDI were higher when detected by NAAT (adjusted incidence rate ratio [aIRR], 1.55; 95% CI, 1.40-1.70; P < .001) and other testing methods (aIRR, 1.47; 95% CI, 1.26-1.71; P < .001). There were no significant changes in testing methods used by hospitals immediately after VBIP implementation. Controlling for CDI testing method, VBIP implementation was associated with a 6% level decline in HO-CDI rates in the immediate postpolicy quarter (aIRR, 0.94; 95% CI, 0.89-0.99; P = .01) and a 4% decline in slope per quarter (aIRR, 0.96; 95% CI, 0.95-0.97; P < .001). Results were similar in a sensitivity analysis using a 1-year roll-in period accounting for the period after the announcement of the HO-CDI VBIP policy and prior to its implementation.

CONCLUSIONS AND RELEVANCE

In this study, VBIP implementation was associated with improvements in HO-CDI rates, independent of CDI testing method. Given that CMS payment policies have not previously been associated with improvements in other targeted health care-associated infection rates, future research should focus on elucidating the specific processes that contributed to improvement in HO-CDI rates to inform the design of future VBIP interventions.

Effectiveness of pulsed xenon ultraviolet disinfection for Clostridioides (Clostridium) difficile surface contamination in a Japanese hospital

BACKGROUND

Contaminated environmental surfaces are important sources of transmission for healthcare-associated pathogens, including Clostridioides (Clostridium) difficile. The effectiveness of manual bleach cleaning and pulsed xenon ultraviolet (PX-UV) disinfection on C. difficile contamination of hospital room high-touch surfaces in Japan was evaluated.

METHODS

The environmental surfaces of 20 C. difficile infection (CDI) isolation rooms were sampled immediately after CDI patients were discharged or transferred. High-touch surfaces were sampled before and after either bleach cleaning or PX-UV disinfection in addition to nonbleach cleaning. Changes in the number of C. difficile-positive samples and bacterial counts for each cleaning method were assessed.

RESULTS

Overall, 286 samples were collected (bleach cleaning, 144 samples; PX-UV disinfection, 142 samples). Before cleaning, the positive rates of C. difficile were 27.8% and 31.0% in bleach cleaning and PX-UV disinfection, respectively. Both bleach cleaning and PX-UV disinfection significantly reduced overall C. difficile-positive samples (P = .018 and P = .002, respectively) and C. difficile colony-forming unit counts (P = .002 and P = .001, respectively).

CONCLUSIONS

PX-UV disinfection in addition to manual nonbleach cleaning effectively reduces C. difficile contamination from high-touch surfaces. Further studies are warranted to evaluate the effect of PX-UV disinfection on CDI rates in Japanese hospitals.

Faucet aerators as a reservoir for Carbapenem-resistant Acinetobacter baumannii: a healthcare-associated infection outbreak in a neurosurgical intensive care unit

Background

On January 7, 2019, we observed an outbreak of healthcare-associated infection (HAI) caused by Carbapenem-resistant Acinetobacter baumannii (CRAB) in the neurosurgical intensive care unit (NSICU). A follow-up epidemiological investigation was conducted, and an emergency response was initiated. We aimed to study the clonal transmission of CRAB and its possible source.

Methods

A matched case-control (1:2) study was performed to identify the possible predisposing factors. A multifaceted intervention was implemented to control the outbreak. We collected environmental samples from patients' rooms and living area of the staff. CRAB isolates were tested for genetic relatedness by Pulsed-Field Gel Electrophoresis (PFGE).

Results

Environmental sampling showed that a faucet aerator was contaminated with A. baumannii. Molecular typing revealed the only outbreak strain, which was isolated from tracheal aspirate cultures of the first case of community-acquired infection and 3 cases of HAI. In environmental samples, the outbreak strain was found only in the faucet aerator of the dining room. This CRAB outbreak was discovered in time, and further progress of this outbreak was prevented through a pre-set emergency response procedure.

Conclusions

The faucet aerator acted as a reservoir for bacteria in the outbreak, and contamination of the faucet aerator might have occurred from splashes originating from handwashing by the healthcare workers (HCWs). In high-risk areas, such as NSICU, the faucet aerators should not be used during an outbreak or they should be regularly cleaned and disinfected. The start-up criteria for the emergency response played a key role in controlling the CRAB outbreak, and its settings should be discussed more widely.