Our weekly wrap-up of antimicrobial stewardship & antimicrobial resistance scans
Study finds high resistance to first-line MDR-TB drug in Georgia
Originally published by CIDRAP News Jul 13
More than half of the multidrug-resistant tuberculosis (MDR-TB) isolates tested in the Republic of Georgia were resistant to one of the first-line treatments for the disease, researchers reported yesterday in BMC Infectious Diseases.
In the study, researchers tested a collection of TB isolates to assess their resistance to the fluoroquinolone antibiotic pyrazinamide (PZA), one of the drugs recommended for first-line treatment of TB and MDR-TB. The isolates were collected as part of a larger study on TB in Georgia, which is recognized as one of the high-burden MDR-TB countries. According to the study, 16.6% of all laboratory-confirmed pulmonary TB patients in Georgia in 2014 were diagnosed with MDR-TB.
Of the 57 isolates tested for PZA susceptibility, 33 (57.9%) were resistant to PZA and 24 (42.1%) were susceptible. All 33 PZA-resistant isolates were MDR-TB strains, and 4 of the 57 isolates were identified as extensively drug-resistant (XDR)-TB. Mutations in the pncA gene, which are largely responsible for conferring resistance to PZA, were found in all 33 PZA-resistant isolates.
Molecular typing identified two major MDR-TB clusters (94-32 and 100-32) in which 67% and 93% of isolates, respectively, were PZA-resistant. Researchers also identified a member of the potentially highly transmissible clade A strain, along with a strain that was distantly related to the clade A strain, suggesting that different branches of the lineage have been introduced to the region.
"Our data contribute to the rising pool of evidence showing the high incidence of PZA resistance among MDR-TB isolates," the authors write. "Health authorities and TB control programs should consider prospective genotyping and PZA testing to assure current effective MDR-TB treatment and to inform the design of new MDR-TB treatment trials."
Jul 12 BMC Infect Dis study
Barriers, solutions for antibiotic stewardship in emergency departments
Originally published by CIDRAP News Jul 13
A study yesterday in the American Journal of Infection Control suggests that antibiotic stewardship in emergency departments (EDs) is hampered by a combination of technological and social factors, but that these barriers could be minimized by using electronic health record–based clinical decision support (EHR CDS) guided by a set of principles and practices.
In the study, researchers conducted interviews and focus groups with hospital and ED leadership, attending ED physicians, nurse practitioners, physician assistants, and residents at Children's Hospital Colorado Health System. The purpose was to elicit a range of information on factors that influence antibiotic prescribing in the ED, provider experience with EHR CDS, and the potential barriers to implementing antibiotic stewardship in the ED using EHR CDS. Data were reviewed and coded using constant comparative analysis and framework analysis until a final set of themes emerged.
The answers from participants revealed that two dominant beliefs framed their perception of antibiotic stewardship in the ED. The first was that efficiency was a core principal guiding antibiotic prescribing practices, as the volume and pace of the ED necessitated that providers manage their time efficiently. The second was autonomy in antibiotic prescribing is often constrained by external influences, including parents or a family's primary care provider (PCP).
These beliefs were reflected in the barriers to stewardship identified by the participants: the rapid pace of the ED, the limited time to interact with the patient and the family, the need to manage parental expectations about antibiotic use, and the need to support the prescribing decisions of the family's PCP.
The participants identified three principles and practices to guide and support antibiotic stewardship in the ED using EHR CDS. The principles included integrating EHR CDS into the existing workflow to support efficiency, maintaining a balance between provider autonomy and standardization, and using antibiotic prescribing data to communicate the scope of the issue to providers. Practices included designing a simple yet flexible EHR CDS user interface, providing performance data to providers regularly, and developing brief communications scripts about antibiotics that providers can use with patients.
Jun 24 Am J Infect Control abstract
Simple molecular typing, hospital data tracks antimicrobial resistance in low-resource settings
Originally published by CIDRAP News Jul 12
Basic molecular typing and routine hospital data can be used in resource-limited settings to do lab surveillance of antimicrobial resistance organizations, according to researchers in Sri Lanka who reported their findings yesterday in BMC Infectious Diseases.
They say antibiotic resistance is a major concern in Sri Lankan healthcare, especially as it relates to healthcare-associated infections. High antibiotic resistance in intensive care unit—known to have high antibiotic pressure--is present throughout the country. Though lab infrastructure has improved in Sri Lanka, no routine typing protocols are in place.
Though next-generation sequencing and multi locus sequence typing are standard typing methods, they aren't readily available in resource-limited settings, so the goal of their study was to see if a simpler method such as random amplification of polymorphic DNA (RAPD) and basic clinical data would be feasible for lab surveillance.
In the retrospective study, the team looked at 70 consecutive Gram-negative isolates obtained from an ICU over a 6-month period, using RAPD typing to gauge antibiotic sensitivity patterns. Seven of the isolates were Escherichia coli, and all were multi-drug resistant and were extended spectrum beta lactamase (ESBL) producers that carried blaCTX-M resistance gene. Fourteen isolates were Klebsiella pneumoniae, and all were multi-drug resistant ESBL producers, all of which harbored the blaSHVgene and all but one of which carried the blaCTX-M gene. All 30 Acinetobacter isolates were multidrug resistant, though only 2 of 15 Pseudomonas aeruginosa isolates were resistant.
RAPD analysis of the four types of organisms found a predominant cluster in each instance, hinting at transfer of organisms within the unit rather than multiple acquisitions from outside environments. The group concluded that simple RAPD typing combined with analysis of hospitalization data could cost-effectively be used to identify trends and spread of resistance organisms.
Jul 11 BMC Infect Dis abstract
Canada reports first case of Candida auris
Originally published by CIDRAP News Jul 11
Canadian researchers are reporting the first case of the drug-resistant fungal pathogen Candida aurisin Canada.
In a case study in Canada Communicable Disease Report, the researchers report that the patient, a 64-year-old individual with a 2-year history of ear complaints, was treated for chronic otitis externa shortly after admission to a tertiary hospital for management of a brain abscess. Previous medical history included a recent hospitalization in India for elective oral surgery. During outpatient follow-up, swabs of the patient's ear discharge revealed the presence of C auris that was resistant to fluconazole and amphotericin B and likely resistant to voriconazole. Case resolution was pending at the time of the report.
The authors of the report say the origin of the infection is unknown but suggest it could be connected to the patient's hospitalization in India, where C auris is endemic.
C auris was originally discovered in 2009 in Japan and since then has emerged as a global health threat owing to its growing resistance to all three major classes of antifungals used to treat Candida infections and its ability to persist on patients and in hospital environments. The US Centers for Disease Control and Prevention (CDC) estimates the mortality rate of C auris infections at approximately 60%. Optimal management for C auris infections is currently unknown.
To help curb the spread of the fungus, the CDC recommends using standard and contact precautions for infected and colonized patients, housing patients in private rooms, cleaning patient rooms daily with a disinfectant active against Clostridium difficile, and informing healthcare facilities when an infected or colonized patient is being transferred in. In the current case, contact precautions had already begun after routine screening had indicated the patient was a carrier of carbapenem-resistant Enterobacteriaceae.
The authors say that since several C auris cases in the United States have been linked to hospitalization abroad, contact precautions and testing may be indicated for anyone who's been hospitalized outside Canada. "This approach may help contain C. auris from nosocomial transmission within and between Canadian healthcare facilities," they write.
Jul 6 Can Commun Dis Rep rapid communication
Study identifies hospital-acquired, MCR-1-carrying isolates in Vietnam
Originally published by CIDRAP News Jul 11
Two colistin-resistant E coli isolates harboring the MCR-1 gene have been identified in medical settings in Vietnam, researchers reported yesterday in the International Journal of Infectious Diseases.
The two E coli isolates—strains NCGM-EC88 and NCGM-E89—were identified among a total of 18 multidrug-resistant E coli isolates obtained through routine screening for multidrug-resistant pathogens at a Vietnamese hospital in 2014; they were isolated from pus and urine samples from two inpatients.
Susceptibility testing showed that both isolates were resistant to ciprofloxacin and colistin but susceptible to carbapenems, while genomic sequencing revealed that the MCR-1 gene was located on the chromosomes of both isolates. Both isolates also contained a single copy of an insertion element, ISAp11, which can contribute to the insertion of MCR-1 from bacterial plasmids into chromosomes.
Multilocus sequence typing revealed that the two E coli isolates belonged to sequence type (ST) 410 and ST457, both of which have been isolated from food and pet animals in several countries.
Since MCR-1 was first identified in E coli samples from pigs, pork products, and humans in China in November 2015, the colisitin-resistance gene has been identified in bacteria from humans, animals, and the environment in more than 30 countries, and studies have documented the spread of the gene to the clinical setting in China. The authors of the study say they believe this is the first report of hospital-acquired E coli isolates harboring MCR-1 in a medical setting in Vietnam.
Jul 10 Int J Infect Dis abstract
Study: Meningitis vaccine associated with reduced rates of gonorrhea
Originally published by CIDRAP News Jul 10
Researchers in New Zealand report today in The Lancet that exposure to the outer-membrane vesical meningococcal B vaccine (MeNZB) was associated with reduced rates of gonorrhea in a retrospective case-control study. It's the first time a vaccine has shown any protection against the sexually transmitted infection.
The study was conducted among patients at sexual health clinics aged 15-30 years who were eligible to receive the MeNZB vaccine and were diagnosed with gonorrhea or chlamydia, or both, from 2004 to 2016. The three-dose vaccine was introduced in 2004 in response to an epidemic strain of the meningococcal B bacterium, and New Zealand offered the vaccine free to anyone under the age of 20 between 2004 and 2006. Researchers wanted to assess the vaccine's effectiveness against gonorrhea on the basis of ecological data suggesting that gonorrhea declined after the use of outer-membrane vesicle (OMV) meningococcal B vaccines in Cuba, New Zealand, and Norway.
Out of 24 sexual health clinics in New Zealand that were approached for data on patients with gonorrhea and chlamydia, 11 participated in the study. For the primary analysis, cases were those with confirmed gonorrhea only, and controls were those with chlamydia only. Co-infection was assigned as either a control or a case. Odds ratios comparing disease outcomes in vaccinated versus unvaccinated participants were estimated using multivariable logistic regression, yielding estimates of vaccine effectiveness.
Overall, there were 14,730 cases and controls: 1,241 gonorrhea cases, 12,486 chlamydia cases, and 1,002 co-infections. Vaccinated individuals were significantly less likely to be cases than controls (511 [41%] vs. 6,424 [51%]). After adjustments were made for sex, age, ethnicity, deprivation, and area, the effectiveness of the MeNZB vaccine against confirmed gonorrhea cases was estimated at 31%. Co-infection with chlamydia was associated with lower vaccine effectiveness (14%).
The authors note that while MeNZB was developed to control an epidemic and is no longer available, the same OMV antigen in MeNZB has been included in a new vaccine that targets a broad range of group B Neisseria meningitidis. "Based upon our results, assessment of this vaccine's potential effect on gonorrhea infection seems warranted," they write.
Given the emergence of gonorrhea strains that are increasingly resistant to the last-line antibiotic regimen, global health officials consider development of a vaccine against gonorrhea an important priority. The authors say modelling suggests a vaccine with 30% efficacy could decrease the prevalence of gonorrhea by more than 30% within 15 years.
Jul 10 Lancet study
G20 leaders pledge to fight antimicrobial resistance
Originally published by CIDRAP News Jul 10
The leaders of the G20 nations reaffirmed their commitment to combatting antimicrobial resistance (AMR) in a communique issued after their recent meeting in Hamburg, Germany.
In the document, which lays out the G20 response to a variety of global challenges, G20 leaders say they aim to implement national actions plans to tackle the spread of AMR in humans, animals, and the environment by the end of 2018, and pledge to promote the prudent use of antibiotics in all sectors. They also committed to raising public awareness about AMR, strengthening infection prevention and control efforts, improving understanding of how antimicrobials affect the environment, and ensuring access to affordable and quality antimicrobials.
As part of their commitment to combatting AMR, the G20 leaders also announced a new global body to oversee research and development of new drugs to address emerging antimicrobial resistance. The Global AMR Collaboration Hub will coordinate efforts to spur research into new antimicrobials, vaccines, alternative therapies, and diagnostic tools and encourage global involvement and investment. It will be open to all G20 countries, G20 guest countries, and non-government donors.
Jul 7-8 G20 Leaders' Declaration