Weekly Digest: U.S. 21st Century Cures Act changes antibiotic approval pathway; carbapenem-resistant bug found on U.S. swine farm

10 Dec 2016

A weekly roundup of news on drug resistance and other topics in global health. 

First large-scale study of recurrent emergency department visits for skin and soft tissue infections. A study from CDDEP researchers and collaborators, published in Epidemiology & Infection, examined factors associated with recurrent emergency department (ED) visits for skin and soft tissue infections (SSTIs), using California emergency department discharge data from 2005 to 2011. More than 16 percent of the nearly 200,000 SSTI records represented repeat visits within six months of the initial encounters. Drug or alcohol abuse and liver disease [odds ratio (OR) 1·4, 95% confidence interval (CI)] and obesity (OR 1·3, 95% CI) are associated with the likelihood of recurrent SSTI visits. Patients whose infections had been subject to incision and draining or aspiration also had a slightly higher risk of a repeat ED visit (OR 1·10, 95% CI). [Epidemiology & Infection]

21st Century Cures Act passed by U.S. Congress. A massive bipartisan bill passed by the United States Congress includes provisions for improved opioid addiction treatment, additional funding for cancer research and the National Institutes of Health, and a special approval pathway for antibiotics to treat multidrug resistant (MDR) infections. The bill aims to prevent overprescription of such antibiotics by requiring manufacturers to label them as intended only for a limited population of patients with serious infections and requires manufacturers to submit promotional materials to the Food and Drug Administration (FDA) for approval. The Act also allows for more rapid updating of antimicrobial susceptibility interpretive criteria, “breakpoints,” to help doctors select the most appropriate antibiotic treatment. Although including widely acceptable provisions, the Act has drawn criticism from a number of public health groups and from some legislators, led by Senator Elizabeth Warren, who points to “huge giveaways” to the pharmaceutical industry. She called the additional NIH funding “a mere figleaf,” and possibly not even a real figleaf. [STAT] [revised 13 December 2016]

Plasmid-mediated carbapenem-resistant Enterobacteriaceae (CRE) identified on U.S. swine farm. Several bacteria species containing resistance-conferring gene IMP-27 were identified in 18 isolates collected from the environment of an industrial U.S. swine farm, though not identified in any pigs. Carbapenems are not approved for use in food animals in the United States and there is no evidence that they were used on the sampled farm. The researchers speculate that colonization with IMP-27 is linked to ceftiofur, a cephalosporin antibiotic used in early stages of pig rearing. The IMP-27 gene was not isolated from pig feces during the study, but the researchers have since reported finding it in fecal isolates from the same farm. [CIDRAP, AAC]

UK and China sign MoU to support joint research in antimicrobial resistance. During the 2016 UK-China High Level People-to-People Dialogue, the nations established numerous agreements including a Memo of Understanding on UK-China Antimicrobial Resistance Research and Innovation. Under the MoU, the Chinese government will match funding contributed by the UK government to support collaborative research on antimicrobial resistance. [Gov.uk]

Children with TB at high mortality risk; first new guidelines in 17 years for TB diagnosis; MDR TB transmission in Shanghai. Before effective treatment was developed (before 1946), about one-fifth of children under 15 years with tuberculosis (TB) died from the disease. In the recent era (after 1980), with treatment, only about 1 percent of children diagnosed with TB die, with a higher case fatality rate for children with HIV. These are the findings of a meta-analysis appearing in Lancet Infectious Diseases.  However, more than 200,000 children died of TB in 2015, and 1 million became infected. The deficit is in access to treatment, signaling a global failure, discussed in a separate comment. [Lancet ID, Lancet ID comment]

Tuberculosis meningitis (TBM) patients with drug-resistant strains face a heightened risk of dying, according to a study in Clinical Infectious Diseases. The study is based on a cohort of 342 patients who reported to the New York City TB registry from 1992 to 2001. More than half—183—died before completing therapy, with a median survival of less than one month. The authors write, “These findings support the continued evaluation of rapid diagnostic techniques and the empiric addition of second-line drugs for patients with clinically suspected drug-resistant TBM.” New guidelines published in Clinical Infectious Diseases, prompted by advances in testing, define high- and low-risk patient populations, provide diagnostic recommendations, and describe a new classification scheme for TB. [Clinical infectious Diseases study, Clinical Infectious Diseases guidelines, CIDRAP]

A study of multidrug-resistant (MDR) tuberculosis (TB) in Shanghai focused on patients diagnosed from 2009 through 2012. Of 324 MDR TB patients with isolates available for genomic analysis, 103 MDR strains were identified (68 with compensatory mutations of rifampicin resistance), belonging to 38 genomic clusters. A transmission network analysis of the 38 genomic clusters indicated that 22 (87 percent) of the 38 clusters accumulated additional drug-resistance mutations during transmission. [Lancet ID study, Lancet ID comment]

In Latin America, a gap in surveillance data on antibiotic consumption and resistance. Writing on the Longitude Prize blog, two Latin America experts in antimicrobial resistance juxtapose the massive scope of the problem—multidrug-resistant organisms cause more than half of all hospital-acquired infections in Brazil, Bolivia and Peru—with the near absence of robust surveillance data on both antibiotic consumption and resistance. In October 2015, the World Health Organization regional committee for the Americas released a plan of action to combat antimicrobial resistance in Latin America. The authors call for governments to support initiatives focusing on surveillance and identification of MDR organisms. [Longitude Prize]