Stewardship / Resistance Scan for Oct 30, 2018

News brief

Study: Resistant urinary tract infections increase risk of relapse

Researchers with the University of Pennsylvania Perelman School of Medicine have found that community-onset urinary tract infections (UTIs) caused by extended-cephalosporin-resistant Enterobacteriaceae (ESC-R EB) are associated with a sevenfold risk of clinical failure and an increase in inappropriate antibiotic therapy, according to a study today in Infection Control and Hospital Epidemiology.

The retrospective cohort study, conducted at two emergency departments and a network of outpatient practices in the University of Pennsylvania Health System, included all patients who presented with community-onset EB UTIs from December 2010 through April 2013. Exposed patients were identified as those who had an ESC-R EB. They were randomly matched 1:1 with patients who had an ESC-susceptible EB UTI. The primary outcome was clinical failure, defined by repeat clinical visit or phone call for ongoing UTI symptoms.

A total of 302 patients were included in the study, with 151 exposed and 151 unexposed. Within the entire cohort, 86 patients (29%) experienced clinical failure. On multivariable analysis, UTI caused by an ESC-R EB was significantly associated with clinical failure (adjusted odds ratio [aOR], 7.07; 95% confidence interval [CI], 3.16 to 15.82; P < .01). Other independent risk factors for clinical failure included infection with Citrobacter spp and a need for hemodialysis.

The researchers also found that a UTI caused by ESC-R EB was a significant independent risk factor for inappropriate initial antibiotic therapy (IIAT) within 48 hours of UTI evaluation (aOR, 4.40; 95% CI, 2.64 to 7.33; P < .01). They concluded, however, that IIAT was only partially responsible for the worse outcomes associated with ESC-R EB.

"This study adds to the evidence that drug-resistant bacteria are an increasing issue, even in the community and even in patients who have something seemingly uncomplicated, like a urinary tract infection," lead study author and University of Pennsylvania clinical epidemiologist Judith Anesi, MD, said in a press release from the Society for Healthcare Epidemiology of America (SHEA), publisher of the journal. "This is an alarming finding, and interventions to curb antibiotic resistance are urgently needed."
Oct 30 Infect Control Hosp Epidemiol abstract
Oct 30 SHEA press release

UK study finds hospital antifungal stewardship reduces costs

An antifungal stewardship (AFS) program centered around specialist input resulted in significant cost savings at a London hospital, with no adverse effects on microbiologic or clinical outcomes, researchers reported today in the Journal of Antimicrobial Chemotherapy.

The AFS program at St. George's Hospital, instituted in October 2010, involves all patients receiving antifungal therapy with amphotericin B, echinocandins, intravenous fluconazole, flucytosine, or voriconazole. All identified patients are seen on a weekly stewardship ward round by an infectious diseases consultant and antimicrobial pharmacist. To determine the effectiveness of the program, researchers collected clinical, microbiologic, and financial outcome data from October 2010 to September 2016.

A total of 432 patients were reviewed 769 times during the study period. The most common drug initiated was amphotericin B (181 patients, 35%), followed by intravenous fluconazole (142 patients, 29%) and echinocandins (120 patients, 23%). In the case of empirical prescribing, 82% (150/183) of patients were subsequently found to have no evidence of invasive fungal infection (IFI). Advice was offered in 64% of reviews (494/769) and was followed in 84% of evaluable recommendations. Of 138 patients prescribed empirical antifungal therapy who had no IFI, 62% had their prescriptions stopped within a week, compared with 44% in a pre-intervention 2009 audit.

Following implementation of the program, annual antifungal expenditure fell by 30%, then increased to 20% above pre-intervention (2009-10) over a 5-year period. But this was a significantly lower rise compared with national antifungal expenditures, which doubled over the same period. Inpatient mortality, Candida species distribution, and rates of resistance were not adversely affected by the intervention.

"In summary, we demonstrate that an AFS program is readily implementable and sustainable over 6 years, offering a large scope for targeted intervention to prevent unnecessary prescribing, with good clinician acceptance and no compromise of clinical outcomes," the authors of the study write.
Oct 30 J Antimicrob Chemother abstract

Study examines risk factors for carbapenem-resistant Pseudomonas

In a study yesterday in the Journal of Antimicrobial Chemotherapy, French researchers determined that the risk of acquiring carbapenem-resistant Pseudomonas aeruginosa (CRPA) was associated with carbapenem exposure and with exposure to beta-lactams inactive against P aeruginosa.

The multicenter prospective case–case-control study included 1,808 adults hospitalized in 10 French intensive care units in 2009. Cases were patients with CRPA and patients with carbapenem-susceptible P aeruginosa (CSPA), and controls were patients without P aeruginosa. The researchers investigated antibiotics associated with CRPA isolation and with CSPA isolation after adjusting for non-antibiotic exposures and inpatient characteristics.

Fifty-nine CRPA, 83 CSPA, and 142 control patients were compared. In multivariable analysis, after adjustment for confounders and other non-antibiotic exposures, CRPA cases were independently associated with exposure to carbapenems (odds ratio [OR], 1.205; 95% CI, 1.079 to 1.346) and with exposure to a group of beta-lactams inactive against P aeruginosa (OR, 1.101; 95% CI, 1.010 to 1.201). The antibiotics included amoxicillin, amoxicillin-clavulanic acid, oxacillin, cloxacillin, ertapenem, and first- and second-generation cephalosporins. Conversely, exposure to beta-lactams active against P aeruginosa was an independent protective factor for CSPA isolation (OR, 0.868; 95% CI, 0.722 to 0.976).

The authors of the study hypothesize that the increased risk for CRPA associated with beta-lactams inactive against P aeruginosa may be due to antibiotic selection pressure, with the selection of intestinal flora making the host more susceptible to colonization by resistant strains. They conclude that clinicians should weigh the potential benefits of administering these antibiotics against the increased risk of CRPA infection.
Oct 29 J Antimicrob Chemother abstract

News Scan for Oct 30, 2018

News brief

Suspected AFM reports climb to 191 as more cases confirmed

In its weekly update yesterday the US Centers for Disease Control and Prevention (CDC) said 36 more suspected acute flaccid myelitis (AFM) cases are under investigation, raising the national total since the first of the year to 191.

Also, 10 more suspected cases were confirmed as AFM, which requires a detailed review of a patient's clinical syndrome and radiographic findings, raising that number to 72. The confirmed cases are from 24 states, an increase of 2 from the previous week.

Earlier this month the CDC said that it and state health officials were investigating a spike in AFM, similar to steep rises that occurred in 2014 and 2016. The condition, marked by a sudden onset of polio-like symptoms that include limb weakness and decreased muscle tone, is extremely rare. So far, no consistent common cause has been found, but researchers are exploring possible roles for infectious diseases such as enterovirus D68 (EV-D68) and environmental toxins.

Most patients with AFM recover quickly, but paralysis symptoms persist for some, requiring ongoing care.

A recent study that compared the neurologic effects of past and recent EV-D68 clades in mice found that only the 2014 isolate from the United States damaged neuronal cells and that only the recent US strain caused paralysis symptoms in mice.
Oct 29 CDC AFM investigation update
Oct 16 CIDRAP News story "CDC, partners probe 127 polio-like cases in 22 states"

Brazilian monkeys infected with Zika hint at sylvatic transmission

Several Brazilian monkeys killed because of suspected yellow fever infections actually had Zika virus, which hints at a possible sylvatic transmission cycle previously unknown to researchers. Information on the discovery was published today in Scientific Reports.

Investigators looked at 82 non-human primate carcasses collected from January to June of 2017 in Brazil. Thirty-two (39%) tested positive for Zika in at least one tissue sample. Infected animals were found in Sao Jose do Rio Preto, Sao Paulo state; and in Belo Horizonte, Minas Gerais state. Viral loads were highest in the animals' kidneys, spleens, and brains.

"If the wild cycle is confirmed, it completely changes the epidemiology of Zika because it means there's a natural reservoir from which the virus can reinfect the human population much more frequently," said Mauricio Lacerda Nogueira, MD, PhD, principal investigator for the study, in a press release from the Sao Paulo Research Foundation (FAPESP), which funded the study

This is the first known discovery of the virus in monkeys since the current outbreak began in Brazil during the winter of 2015-16.
Oct 30 Sci Rep study
Oct 30 FAPESP press release

Study: Half of Saudi camel workers harbor MERS-CoV antibodies

A study today in mBio analyzed blood samples from 30 Saudi Arabian camel workers (CWs) and showed that half (15) tested positive for a MERS-CoV immune response but had no history of significant respiratory disease.

Another four CWs who tested seronegative for MERS-CoV (Middle East respiratory syndrome coronavirus) had specific T-cell responses, which indicated previous MERS-CoV infection.

The study subjects were all adult males who worked at the Riyadh New Camel Market and reported contact with camel oral and nasal secretions and urine. Results were compared with samples collected from healthy controls in Riyadh and Iowa.

Though camel contact is a known risk factor for MERS transmission, a minority of MERS cases involve direct camel exposure. CWs, the authors suggest, may be acting as human reservoirs of the virus and exposing people who do not have direct camel contact.

"Our results indicate that a high proportion of CWs are infected, and this, combined with data demonstrating that patients with subclinical MERS are contagious, suggests a plausible mechanism for how patients without documented camel exposure become infected," the authors said. "It is possible that some healthy contacts of CWs are subclinically infected, while exposed individuals with underlying comorbidities or who are otherwise more susceptible develop clinical disease."
Oct 30 mBio study

Survey shows 89% of Americans deem public health important

Public health is a bipartisan issue, according to a new survey conducted by the de Beaumont Foundation, which found that 89% of participants said public health played an important role in the health of their community.

Two thirds of survey respondents said state government should ensure that citizens have access to basic public health protections, including clean air and water, government emergency services, and maternal and child health. Fifty-seven percent of those polled said they would pay more in taxes to ensure greater access to public health protections, according to the survey by the de Beaumont Foundation.

"Americans overwhelmingly value the protections public health departments deliver and want to ensure that every community has them,” said de Beaumont CEO Brian C. Castrucci, DrPH, MA, in a press release today. "While Americans seem divided on so many issues this election year, they are united in their support for public health because they understand the vital role it plays in their communities."

The survey was conducted via telephone between Aug 31 and Sep 8 of this year and included 1,000 voters nationally, with an over-sample of 498 voters in rural areas. It has a margin of error of plus or minus 3.1% for the national sample and 3.7% for the rural over-sample.
Oct 30 de Beaumont Foundation press release