Clinical and laboratory characteristics of Clostridium difficile infection in patients with discordant diagnostic test results.

The aim of this study was to compare the clinical and laboratory characteristics of Clostridium difficile infection (CDI) in patients with discordant test results for the cytotoxin assay (CYT) and PCR assays. A retrospective study from May to August 2008 and March to May 2010 was performed. CDI was diagnosed in 128 patients. PCR increased the yield of C. difficile cases by 2-fold compared to that of the CYT assay. Fifty-six cases (44%) were detected by PCR only (CYT negative). Forty-nine percent of patients with non-NAP1 strains were detected by PCR only, compared to 28% of those infected with NAP1 strains (P < 0.05). No significant differences were found in the clinical severity of illness and outcome among patients that tested positive for CDI by both tests (CYT and PCR) compared to those that tested positive by PCR only.

Totally implantable venous access device placement by interventional radiologists: are prophylactic antibiotics necessary?

PURPOSE: To determine the rate of early infection for totally implantable venous access devices (TIVADs) placed without antibiotic prophylaxis. MATERIAL AND METHODS: A list of patients who underwent TIVAD placement in 2009 was obtained from the patient archiving and communication system (PACS). This list was cross-referenced to all patients who underwent TIVAD removal from January 1, 2009, through January 30, 2010, to identify TIVADs that were removed within 30 days of placement. Retrospective chart review was performed to record patient demographics, including age, sex, cancer diagnosis, and indication for removal. Concurrent antibiotic therapy, chemotherapy, and laboratory data before and within 30 days of placement were recorded. Central line-associated bloodstream infections (CLABSIs) were identified using U.S. Centers for Disease Control and Prevention (CDC) criteria. RESULTS: There were 1,183 ports placed and 13 removed. CLABSIs occurred in seven (0.6%) patients within 30 days of placement. At the time of TIVAD placement, 81 (7%) patients were receiving antibiotics incidental to the procedure. One patient who received an antibiotic the day of implantation developed a CLABSI. Chemotherapy was administered to 148 (13%) patients on the day of placement. CONCLUSIONS: The rate of early infection without antibiotic prophylaxis before TIVAD placement in the interventional radiology suite is < 1%. Based on these data, use of prophylactic antibiotics for TIVAD placement is not recommended.

SARS-CoV-2 Infection Among Pregnant People at Labor and Delivery and Changes in Infection Rates in the General Population: Lessons Learned From Illinois.

OBJECTIVES: The Illinois Department of Public Health (IDPH) assessed whether increases in the SARS-CoV-2 test positivity rate among pregnant people at labor and delivery (L&D) could signal increases in SARS-CoV-2 prevalence in the general Illinois population earlier than current state metrics. MATERIALS AND METHODS: Twenty-six birthing hospitals universally testing for SARS-CoV-2 at L&D voluntarily submitted data from June 21, 2020 through January 23, 2021, to IDPH. Hospitals reported the daily number of people who delivered, SARS-CoV-2 tests, and test results as well as symptom status. We compared the test positivity rate at L&D with the test positivity rate of the general population and the number of hospital admissions for COVID-19-like illness by quantifying correlations in trends and identifying a lead time. RESULTS: Of 26 633 reported pregnant people who delivered, 96.8% (n = 25 772) were tested for SARS-CoV-2. The overall test positivity rate was 2.4% (n = 615); 77.7% (n = 478) were asymptomatic. In Chicago, the only region with a sufficient sample size for analysis, the test positivity rate at L&D (peak of 5% on December 7, 2020) was lower and more stable than the test positivity rate of the general population (peak of 14% on November 13, 2020) and lagged hospital admissions for COVID-19-like illness (peak of 118 on November 15, 2020) and the test positivity rate of the general population by about 10 days (Pearson correlation = 0.73 and 0.75, respectively). PRACTICE IMPLICATIONS: Trends in the test positivity rate at L&D did not provide an earlier signal of increases in Illinois's SARS-CoV-2 prevalence than current state metrics did. Nonetheless, the role of universal testing protocols in identifying asymptomatic infection is important for clinical decision making and patient education about infection prevention and control.

Relapse versus reinfection: surveillance of Clostridium difficile infection.

Molecular typing was used to examine surveillance definitions for recurrent Clostridium difficile-associated diarrhea. Among 102 patients, 85 had a second episode within 8 weeks, 88% of which were relapses. Of 49 second episodes occurring after > 8 weeks, 65% were relapses. Categorization of a recurrent episode occurring after >8 weeks as a new infection may misrepresent the majority of episodes for surveillance.

Secreted-protein response to sigmaU activity in Streptomyces coelicolor.

The filamentous bacterium Streptomyces coelicolor forms an aerial mycelium as a prerequisite to sporulation, which occurs in the aerial hyphae. Uncontrolled activity of the extracytoplasmic function sigma factor sigmaU blocks the process of aerial mycelium formation in this organism. Using a green fluorescent protein transcriptional reporter, we have demonstrated that sigU transcription is autoregulated. We have defined a sigmaU-dependent promoter sequence and used this to identify 22 likely sigmaU regulon members in the S. coelicolor genome. Since many of these genes encode probable secreted proteins, we characterized the extracellular proteome of a mutant with high sigmaU activity caused by disruption of rsuA, the presumed cognate anti-sigma factor of sigmaU. This mutant secreted a much greater quantity and diversity of proteins than the wild-type strain. Peptide mass fingerprinting was used to identify 79 proteins from the rsuA mutant culture supernatant. The most abundant species, SCO2217, SCO0930, and SCO2207, corresponded to secreted proteins or lipoproteins of unknown functions whose genes are in the proposed sigmaU regulon. Several unique proteases were also detected in the extracellular proteome of the mutant, and the levels of the protease inhibitor SCO0762 were much reduced compared to those of the wild type. Consequently, extracellular protease activity was elevated about fourfold in the rsuA mutant. The functions of the proteins secreted as a result of sigmaU activity may be important for combating cell envelope stress and modulating morphological differentiation in S. coelicolor.

Use of Disinfection Cap to Reduce Central-Line-Associated Bloodstream Infection and Blood Culture Contamination Among Hematology-Oncology Patients.

OBJECTIVE: In this study, we examined the impact of routine use of a passive disinfection cap for catheter hub decontamination in hematology-oncology patients. SETTING: A tertiary care cancer center in New York City. METHODS: In this multiphase prospective study, we used 2 preintervention phases (P1 and P2) to establish surveillance and baseline rates followed by sequential introduction of disinfection caps on high-risk units (HRUs: hematologic malignancy wards, hematopoietic stem cell transplant units and intensive care units) (P3) and general oncology units (P4). Unit-specific and hospital-wide hospital-acquired central-line-associated bloodstream infection (HA-CLABSI) rates and blood culture contamination (BCC) with coagulase negative staphylococci (CONS) were measured. RESULTS: Implementation of a passive disinfection cap resulted in a 34% decrease in hospital-wide HA-CLABSI rates (combined P1 and P2 baseline rate of 2.66-1.75 per 1,000 catheter days at the end of the study period). This reduction occurred only among high-risk patients and not among general oncology patients. In addition, the use of the passive disinfection cap resulted in decreases of 63% (HRUs) and 51% (general oncology units) in blood culture contamination, with an estimated reduction of 242 BCCs with CONS. The reductions in HA-CLABSI and BCC correspond to an estimated annual savings of $3.2 million in direct medical costs. CONCLUSION: Routine use of disinfection caps is associated with decreased HA-CLABSI rates among high-risk hematology oncology patients and a reduction in blood culture contamination among all oncology patients.

Estimating risk of C. difficile transmission from PCR positive but cytotoxin negative cases.

BACKGROUND: The use of molecular methods to diagnose Clostridium difficile infection (CDI) has improved diagnostic yield compared to conventional methods. However, PCR testing can detect colonization and has introduced several practical challenges pertaining to need for treatment and isolation of cases. METHODS: For all new cases detected by real-time PCR, concurrent cytotoxin assay was performed and genetic characterization with MLVA (multi-locus variable number tandem repeat analysis) was done to determine relatedness. We used PCR cycle threshold (Ct) of detection as surrogate marker for bacterial burden in stool. RESULTS: Overall, 54 cases of CDI were detected during the study period. 42 were concurrently tested by CYT and characterized by MLVA .MLVA analysis revealed marked genetic diversity with no ongoing outbreaks; four cases were due to NAP1 strain. CYT -/PCR + cases had a higher median Ct value of detection compared to CYT+/PCR + cases (28.2 vs 22.5; p = 0.01). Among 25 strains that were genetically related, 9/11 isolates in this dominant cluster were positive by CYT compared to 4/14 in non-dominant clusters (p = 0.02). CONCLUSION: CYT-/PCR+ cases contribute to hospital based transmission. However, the risk of transmission of C. difficile from CYT +/PCR+ cases may be higher than those that are CYT-/PCR+.

Long-term central venous catheter use and risk of infection in older adults with cancer.

PURPOSE: Long-term central venous catheters (CVCs) are often used in patients with cancer to facilitate venous access to administer intravenous fluids and chemotherapy. CVCs can also be a source of bloodstream infections, although this risk is not well understood. We examined the impact of long-term CVC use on infection risk, independent of other risk factors such as chemotherapy, in a population-based cohort of patients with cancer. PATIENTS AND METHODS: We conducted a retrospective analysis using SEER-Medicare data for patients age > 65 years diagnosed from 2005 to 2007 with invasive colorectal, head and neck, lung, or pancreatic cancer, non-Hodgkin lymphoma, or invasive or noninvasive breast cancer. Cox proportional hazards regression was used to examine the relationship between CVC use and infections, with CVC exposure as a time-dependent predictor. We used multivariable analysis and propensity score methods to control for patient characteristics. RESULTS: CVC exposure was associated with a significantly elevated infection risk, adjusting for demographic and disease characteristics. For patients with pancreatic cancer, risk of infections during the exposure period was three-fold greater (adjusted hazard ratio [AHR], 2.93; 95% CI, 2.58 to 3.33); for those with breast cancer, it was six-fold greater (AHR, 6.19; 95% CI, 5.42 to 7.07). Findings were similar when we accounted for propensity to receive a CVC and limited the cohort to individuals at high risk of infections. CONCLUSION: Long-term CVC use was associated with an increased risk of infections for older adults with cancer. Careful assessment of the need for long-term CVCs and targeted strategies for reducing infections are critical to improving cancer care quality.

Central line-associated bloodstream infection surveillance outside the intensive care unit: a multicenter survey.

OBJECTIVE: The success of central line-associated bloodstream infection (CLABSI) prevention programs in intensive care units (ICUs) has led to the expansion of surveillance at many hospitals. We sought to compare non-ICU CLABSI (nCLABSI) rates with national reports and describe methods of surveillance at several participating US institutions. DESIGN AND SETTING: An electronic survey of several medical centers about infection surveillance practices and rate data for non-ICU patients. PARTICIPANTS: Ten tertiary care hospitals. METHODS: In March 2011, a survey was sent to 10 medical centers. The survey consisted of 12 questions regarding demographics and CLABSI surveillance methodology for non-ICU patients at each center. Participants were also asked to provide available rate and device utilization data. RESULTS: Hospitals ranged in size from 238 to 1,400 total beds (median, 815). All hospitals reported using Centers for Disease Control and Prevention (CDC) definitions. Denominators were collected by different means: counting patients with central lines every day (5 hospitals), indirectly estimating on the basis of electronic orders ([Formula: see text]), or another automated method ([Formula: see text]). Rates of nCLABSI ranged from 0.2 to 4.2 infections per 1,000 catheter-days (median, 2.5). The national rate reported by the CDC using 2009 data from the National Healthcare Surveillance Network was 1.14 infections per 1,000 catheter-days. CONCLUSIONS: Only 2 hospitals were below the pooled CLABSI rate for inpatient wards; all others exceeded this rate. Possible explanations include differences in average central line utilization or hospital size in the impact of certain clinical risk factors notably absent from the definition and in interpretation and reporting practices. Further investigation is necessary to determine whether the national benchmarks are low or whether the hospitals surveyed here represent a selection of outliers.

Hospital-onset Clostridium difficile infection rates in persons with cancer or hematopoietic stem cell transplant: a C3IC network report.

A multicenter survey of 11 cancer centers was performed to determine the rate of hospital-onset Clostridium difficile infection (HO-CDI) and surveillance practices. Pooled rates of HO-CDI in patients with cancer were twice the rates reported for all US patients (15.8 vs 7.4 per 10,000 patient-days). Rates were elevated regardless of diagnostic test used.

Practically speaking: rethinking hand hygiene improvement programs in health care settings.

BACKGROUND: Hand hygiene is widely recognized as the single most effective means of reducing health care-associated infections. Implementing a credible hand hygiene program and maintaining high compliance among staff is both expected and required of hospitals. However, beyond general guidelines, few resources are available for establishing an institution-wide hand hygiene program that is both successful and sustainable over the long term. METHODS: Beginning in 2008, we completely overhauled the approach to hand hygiene at our institution. We created small teams consisting of a representative from Quality Assessment, an Infection Prevention Practitioner, and staff from a particular unit. Teams began by discussing the current barriers to hand hygiene success. They then set their own goals for hand hygiene compliance. Staff learned the World Health Organization (WHO) hand hygiene guidelines, which recently had been adopted as part of hospital infection prevention policy. Using the WHO guidelines, teams diagrammed detailed workflows for several of their most common patient care tasks. Wherever hand hygiene was indicated, the workflow was marked with a number corresponding to one or more of the WHO's "5 moments for hand hygiene." At the end of the 12-week period, staff members were trained to observe each other and began officially collecting and submitting data to Infection Prevention. RESULTS: Between 2006 and 2008, our average institutional hand hygiene compliance held steady at 60%-70%. After the new program was launched in 2008, compliance reached 97% and has been maintained at this level ever since. In addition to the 19 areas of the hospital that were observed previously, 15 ambulatory facilities and 5 regional sites are now included in the data. CONCLUSION: This article describes a novel approach to measuring, monitoring, and ultimately increasing hand hygiene compliance at our hospital. Our objective is to provide concrete, practical strategies for other institutions faced with the challenge of building or revamping their own hand hygiene programs.