Our weekly wrap-up of antimicrobial stewardship & antimicrobial resistance scans
WHO: Global TB reduction efforts lag, disease burden higher than thought
Originally published by CIDRAP News Oct 13
The World Health Organization (WHO) warned today that efforts to reduce the global burden of tuberculosis (TB) need to move faster to meet international targets, and that detection and treatment gaps remain a significant roadblock in the fight against multidrug-resistant TB (MDR-TB).
According to the WHO's Global Tuberculosis Report 2016, there were an estimated 10.4 million new TB cases in 2015, with 60% of those cases occurring in just six countries—India, China, Indonesia, Nigeria, Pakistan, and South Africa. The 2015 numbers, which include new surveillance and survey data from India, show that the global TB burden is higher than previously estimated. Of the estimated 10.4 million new cases, only 6.1 million were detected and officially notified.
An estimated 1.4 million people died from TB last year. Although the number of TB deaths fell by 22% between 2000 and 2015, it remains one of the top 10 causes of death worldwide.
The report estimates that 480,000 people developed MDR-TB in 2015. But while that number did not change from 2014, an additional 100,000 people were diagnosed as having rifampicin-resistant TB (RR-TB). Rifampicin is one of the four first-line drugs used to treat the disease. India, China, and Russia accounted for 45% of the MDR/RR-TB cases.
The MDR-TB estimates are likely low, however, given that only 30% of the 3.4 million new bacteriologically confirmed and previously treated TB cases notified globally were reported to have had drug susceptibility testing for rifampicin, the WHO said. In addition, only 20% of those patients eligible for MDR-TB treatment (125,000) received it in 2015. The global cure rate for MDR-TB remained at 52%.
The WHO's End TB Strategy, which was approved by the World Health Assembly in 2014, calls for a 90% reduction in TB deaths and an 80% reduction in the TB incidence rate by 2030, compared with 2015. The new report shows the world has a long way to go to meet those targets and is short on money, with investments in low- and middle-income countries falling $2 billion short of the $8.3 billion needed. The WHO says that funding gap could increase to $6 billion by 2020 if current funding levels don't increase.
"We face an uphill battle to reach the global targets for tuberculosis," WHO Director-General Margaret Chan, MD, MPH, said in a press release. "There must be a massive scale-up of efforts, or countries will continue to run behind this deadly epidemic and these ambitious goals will be missed."
Oct 13 WHO Global Tuberculosis Report 2016
Oct 13 WHO press release
Study documents drug resistance in Corynebacterium striatum
Originally published by CIDRAP News Oct 13
A study yesterday identifies Corynebacterium striatum as an emerging drug-resistant threat that is associated with increased use of parenteral antimicrobial drugs.
The case-control study, published in Emerging Infectious Diseases, retrospectively identified 179 C striatum isolates in a clinical database and used patient records to obtain clinical relevance, in vitro susceptibility, and length of parenteral antimicrobial use. Then, in a subset of 38 patients who had hardware-associated osteomyelitis or infections of implanted cardiac devices, the researchers performed matched case-control analysis to examine length of parenteral therapy in C striatum cases compared with patients who had coagulase-negative staphylococci.
Susceptibility testing showed that 87 of 121 clinical isolates (71%) from patients infected with C striatum were resistant to all oral antimicrobial drugs tested, including penicillin, tetracycline, clindamycin, erythromycin, and ciproflaxin. The case-control analysis found that patients infected with C striatum were on parenteral antimicrobial drugs more than twice as long as the patients with coagulase-negative staphylococci (69 ± 5 days vs 25 ± 4 days). In addition, the researchers found that serious adverse events associated with parenteral antimicrobial drugs were more likely to be found in the C striatum patients.
The authors say the findings highlight the need to identify Corynebacterium to the species level and perform susceptibility testing for any isolate believed to be clinically meaningful. Furthermore, the high levels of resistance found in C striatum to easily tolerated oral antibiotics indicate the need for development of new oral antimicrobial agents.
Oct 12 Emerg Infect Dis article
Dogs may be a source of community-acquired C difficile infection
Originally published by CIDRAP News Oct 12
A new study in PLoS One suggests that companion animals may be a potential source of community-acquired Clostridium difficile infection (CDI) in humans.
With US dog ownership estimated to be 36%, and a small body of research suggesting that farm animals and companion animals are contributors to community-associated reservoirs for C difficile bacteria, the authors of the study hypothesized that domestic dogs could be a potential source of community-acquired CDI. To determine the prevalence and diversity of C difficile in the dog population, the authors systematically collected and screened 216 canine fecal samples from a single city (Flagstaff, Ariz.), genotyped the C difficile isolates obtained from those samples, and then compared the results to a global database of strains isolated from human CDIs.
The investigators found C difficile isolates in 37 of the 216 samples, for an overall colonization rate of 17.1%, with 10% of those samples containing toxigenic strains that are known to cause human disease.
Whole-genome sequencing identified 44 unique strains within the 37 positive samples representing 12 distinct sequence types. Eleven of these sequence types have also been isolated from human CDIs, and 6 are among the most frequently identified in human infections. While none of the toxigenic strains identified were hyper-virulent, the researchers did identify 4 isolates that carried antimicrobial resistance determinants.
The authors say the results indicate that C difficile types similar to those that cause disease in humans are widespread in dog feces, making dogs a potential source of community-acquired CDI. They suggest future research should include looking at C difficile isolates from humans and dogs within a single household.
Oct 10 PLoS One study
ASP at a children's hospital is tied to declines in antimicrobial use
Originally published by CIDRAP News Oct 11
Parenteral antimicrobial use at a Tennessee children's hospital decreased at a rate of 11.1% a year after implementation of an antibiotic stewardship program (ASP), according to a new study published in the Journal of the Pediatric Infectious Disease Society.
In an evaluation of the ASP implemented at Monroe Carell Jr. Children's Hospital at Vanderbilt in 2012, researchers examined 643 interventions that were made by the ASP team from January 2013 to June 2014. The team included a pharmacist with infectious disease (ID) training and an attending pediatric ID physician, and the primary strategy was a prospective audit with feedback (PAWF)—a method that allows the ASP team to interact directly with prescribers to tailor antibiotic therapy.
The 11.1% decline in parenteral antimicrobial use at the hospital after the ASP implementation, which included parenteral antimicrobials in all classes, was nearly twice the median decline observed at 45 other children's hospitals in the Pediatric Health Information System (PHIS) database over the same period. Monthly median expenditures for all parenteral antimicrobials decreased by more than $42,000.
These findings were not unexpected or surprising. But the researchers say that, in addition to further establishing the value of ASPs, the results help distill some of the factors associated with compliance with PAWF recommendations.
Analysis of the interventions showed that in 495 of the 643 interventions (77%), prescribers adhered to the nonbinding recommendations of the ASP team, with a notable difference in adherence observed among different provider types. In particular, recommendations made to a team pharmacist were most likely to succeed, followed by recommendations made to a resident. Nurse practitioners were least likely to adhere to ASP recommendations.
Understanding these compliance factors, the authors say, can help stewardship programs maximize efficacy.
Oct 7 J Pediatr Infect Dis Soc abstract
Los Angeles hospitals will have to start reporting CRE infections
Originally published by CIDRAP News Oct 10
Hospitals in Los Angeles County will soon be required to report when patients are infected with carbapenem-resistant Enterobacteriaceae (CRE), according to the Los Angeles Times.
The deputy director of the county's acute communicable disease control program told the paper that health officials will use the data to look for clusters of infections and prevent outbreaks but will not report the names of the hospitals reporting the infections and won't require hospitals to report whether CRE patients die or survive. Nursing homes and clinics will be exempt from the new reporting rule.
The Times reports that the county had stopped requiring hospitals to report CRE infections in 2012 because of limited resources. But the highly drug-resistant bacteria have caused three outbreaks in Los Angeles hospitals since 2014. The outbreaks have been linked to a medical scope that is hard to disinfect, even when the manufacturers' cleaning instructions are followed.
The story suggests that the policy change is in response to the death of a Manhattan Beach resident who developed a CRE infection after surgery at Torrance Medical Center in 2014. The patient reportedly had two scope procedures before the surgery.
According to the Centers for Disease Control and Prevention (CDC), more than 9,000 healthcare-associated infections are caused by CRE each year. Because CRE have become resistant to nearly all antibiotics used to treat them, more than half of all bloodstream infections caused by the bacteria result in death.
Oct 6 Los Angeles Times story
April 2013 CDC antibiotic resistance threats report
Mar 5, 2013, CIDRAP News story "CDC warns of drug-resistant Enterobacteriaceae"