News Scan for Dec 07, 2017

News brief

New Lyme tests offer faster, more accurate diagnosis, experts say

A new analysis in Clinical Infectious Diseases suggests that new tests can be used to help diagnose Lyme disease, the most prevalent tick-borne illness in North America.

Each year, there are more than 300,000 cases of Lyme disease diagnoses in America. When the telltale "bullseye" rash isn't present, clinicians need to rely on lab tests. The most comon tests are those used to detect antibodies to the Lyme-causing Borrellia bacteria in the patient.

Unfortunately, most current tests—approved by the US Food and Drug Administration based on principles more than 20 years old—can result in higher rates of false-negatives and false-positives compared with newer tests, according to the analysis.

"New tests are more exact and are not as susceptible to the same false-positive or false-negative results associated with current tests," said Steven Schutzer, MD, of Rutgers University, in a university news release. This is because they can use as targets more specific parts of the bacteria.

A team of experts said newer diagnostic tests just developed and others in development may more accurately and quickly detect infection with Borrelia bacteria, which are transmitted by ticks. Early treatment with antibiotics leads to better patient outcomes, the authors said.
Dec 7 Clin Infect Dis analysis
Dec 7 Rutgers University press release
Dec 7 Cold Spring Harbor Laboratory news release

Cases of Guinea worm disease decline to 8 in first half of 2017

Although cases of Guinea worm disease (dracunculiasis) increased slightly worldwide in 2016, officials have reported only eight cases in the first half of this year in only one country, which is promising news for potential eradication of the disease, researchers from the US Centers for Disease Control and Prevention (CDC) reported today in Morbidity and Mortality Weekly Report (MMWR).

The number of global cases rose from 22 in four nations in 2015 to 25 in three nations in 2016. But from January to June of this year only 8 cases were reported, all in Chad. That compares with 10 cases in three countries in the same period of 2016.

In addition, the number of infected domestic dogs more than doubled from 2015 to 2016—from 503 to 1,011—but then declined to 537 during January through June 2017, compared with 653 during the same period in 2016.

"The emergence of infected dogs in Chad especially, and program disruptions caused by civil unrest and insecurity in Mali and South Sudan, are now the greatest challenges to interrupting transmission," the investigators wrote. "Rigorous implementation (including recent interventions to prevent transmission to and from dogs) must be maintained in Chad to ensure continued progress during 2017 and beyond."
Dec 8 MMWR report

Stewardship / Resistance Scan for Dec 07, 2017

News brief

Inappropriate antibiotics shown costly for Enterobacteriaceae infections

Editors note: This scan was update Dec 7 to note the funding source for the study.

A nationwide study of US patients with Enterobacteriaceae infections suggests that inappropriate empiric therapy (IET) is associated with higher 30-day readmission rates and is costlier than adequate treatment.

The retrospective cohort study, published yesterday in Antimicrobial Resistance & Infection Control, looked at all adult patients admitted to 175 US hospitals from 2009 through 2013 with urinary tract infection (UTI), pneumonia, or sepsis as the principal diagnosis. IET was defined as failure to administer an antibiotic therapy active in vitro against the culture-confirmed pathogen within 2 days of admission.

To understand the full economic impact of IET among patients with Enterobacteriaceae infections, the researchers sought to explore the direct costs associated with antibiotics prescribed and those attributable to delaying adequate treatment, and to examine rates of hospital readmission at 30 days.

Among the 40,137 patients diagnosed as having Enterobacteriaceae infections, 4,984 (13.2%) received IET. Carbapenem-resistant Enterobacteriaceae (CRE) was more frequent in patients given IET (13%) than non-IET patients (1.6%). While the proportion of total hospital costs represented by antibiotics were similar among IET and non-IET patients (3.3% vs. 3.4%), each additional day of inadequate therapy added $766 to the total cost of hospitalization. And while 30-day readmission rates were above 20% in both groups, they were significantly higher in the IET patients compared with the non-IET patients (25.6% vs. 21.1%).

The authors of the study, which was co-authored by two employees and two consultants of primary sponsor The Medicines Company, say the findings are significant because they suggest the additional costs and worsened outcomes associated with IET may outweigh concerns about using newer, more expensive broad-spectrum antibiotics. "Given the known improvement in the chances of survival with immediate appropriate treatment, this serves as further compelling evidence to start broadly and de-escalate as necessary," they write.
Dec 6 Antimicrob Resist Infect Control study

Study evaluates quick response to Candida auris infection

A small quasi-experimental study yesterday in Infection Control and Hospital Epidemiology describes efforts to limit dissemination of Candida auris at a New York hospital after the fungal pathogen was identified in a patient.

The patient, a 59-year-old woman with metastatic colon cancer, was found to have C auris in her bloodstream 6 days after admission to the hospital and remained colonized until her death on day 21 of hospitalization. On day 7, the patient and her roommate were placed on enhanced contact precautions and moved to private rooms, and their former room was terminally cleaned with peracetic acid–hydrogen peroxide (PA-HP) and ultraviolet (UV) light. In addition, hospital staff moved all patients in the oncology ward to terminally cleaned rooms.

Sampling of the index patient and other patients on the ward, along with environmental sampling, was conducted, and 180 samples (48 from 18 different patients, and 132 from 32 different surfaces) were collected. C auris was isolated from 3 of 132 surface samples on days 8, 9, and 15 of ward occupancy but from no patient samples. Isolates from the environment and the case-patient were genetically identical and most closely related to the 2013 India CA-6684 strain, indicating the source of the environmental contamination was the case-patient, who likely acquired the pathogen from another New York hospital.

Although the authors can't say whether the timely feedback from the referral laboratories, cleaning with PA-HP and UV, and high hand hygiene compliance on the ward limited the spread of C auris, the pathogen was isolated from fewer surfaces and patients than noted in prior reports. They say the response is noteworthy for the multifaceted interagency approach taken and for the extensive attempt at environmental assessment.
Dec 6 Infect Control Hosp Epidemiol study

Improper antifungal prescribing not tied to death in Candida blood infections

Inappropriate antifungal therapy did not have an impact on mortality in patients with Candida bloodstream infection (CBSIs), according to a study yesterday in BMC Infectious Diseases.

Researchers in Mexico looked at patients admitted to two referral tertiary centers in Mexico City from June 2008 to July 2014 with a blood culture positive for Candida. CBSIs represent 10% of all bloodstream infections, and mortality is high (46% to 75%). The purpose was to evaluate the impact on mortality of the Clinical and Laboratory Standards Institute's (CLSI's) updated clinical breakpoints for antifungal therapy for the most common Candida species. The breakpoints were updated in 2012.

Overall, 149 episodes of CBSI were included for analysis. The most frequent species identified were C albicans (40%), C tropicalis (23%), and C glabrata complex (20%). According to the 2012 CLSI breakpoints, 8.7% of the patients received inappropriate antifungal therapy. The 30-day mortality among CBSI patients was 38%.

In multivariate analysis, severe sepsis (odds ratio [OR], 3.4) and cirrhosis (OR, 36) were independently associated increased 30-day mortality, while early central venous catheter removal and previous antifungal therapy were associated with decreased 30-day mortality. Inappropriate antifungal therapy, as defined by the 2012 CLSI breakpoints, was not associated with 30-day mortality (OR, 0.19).

"Mortality in CBSI remains high due to disease severity and comorbidities such as cirrhosis at the time of diagnosis," the authors conclude.
Dec 6 BMC Infect Dis study