Shiloh
Editor, Senior Moderator
Source: https://www.cidrap.umn.edu/news-perspective/2021/04/news-scan-apr-21-2021
News Scan for Apr 21, 2021
Colistin resistance in Enterobacterales; H9N2 flu in China, Cambodia
Filed Under:
Avian Influenza (Bird Flu); Antimicrobial Stewardship
Risk factors, mechanisms noted in colistin-resistant Enterobacterales
A study of colistin-resistant Enterobacterales (CORE) isolates from patients in southeast Michigan found that increased age and prior antibiotic receipt were associated with increased risk of CORE colonization or infection, researchers reported today in Open Forum Infectious Diseases.
In the study, one of the first to provide large-scale colistin resistance data on clinical Enterobacterales isolates in the United States, researchers with the University of Michigan and Case Western Reserve University examined routine clinical isolates obtained in single tertiary health system in Ann Arbor from January 2016 through March 2017.
Patients with CORE isolates were matched 1:1 with patients with colistin-susceptible Enterobacterales (COSE) isolates and uninfected control patients, and multivariable logistics regression was used to compare clinical and microbiologic features. The researchers also conducted whole-genome sequencing (WGS) on a subset of CORE isolates.
Of 16,373 tested clinical isolates, 166 (0.99%) were colistin-resistant, representing 103 unique patients. CORE specimens included 45 Enterobacter isolates, 31 Escherichia coli isolates, and 27 Klebsiella pneumoniae isolates. Multivariable analysis of 103 CORE isolates, 103 COSE isolates, and 102 uninfected controls found that antibiotic exposure in the prior 90 days (odds ratio [OR], 2.22; 95% confidence interval [CI], 1.23 to 4.03) and being age 55 and older (OR, 4.06; 95% CI, 2.24 to 7.36) were predictors of CORE. But notably, none of the 103 patients with CORE were exposed to colistin before culture collection. The same factors were also predictors of COSE.
Among the 33 isolates that underwent WGS, several genetic mutations associated with colistin resistance were found; three MCR-1 genes, one MCR-1.1 gene, and four pmrA/B mutations were identified in E coli isolates, and 5 mgrB and pmrA mutations were detected on K pneumoniae isolates. Mechanisms of colistin resistance among Enterobacter isolates could not be determined.
"Further studies are needed to determine the drivers of and determinants of polymyxin resistance among Enterobacterales, including exposure to non-polymyxin antimicrobials," the authors concluded.
Apr 21 Open Forum Infect Dis abstract
H9N2 avian flu virus infects kids in China, Cambodia
China has reported two more H9N2 avian flu infections in humans, both involving children who are from two different provinces, the World Health Organization (WHO) Western Pacific regional office said in its most recent avian influenza update.
One of the patients is a 10-year-old boy from Fujian province whose symptoms began on Feb 28. The investigation found no history of exposure to poultry. The other is a 2-year-old girl from Hubei province who got sick on Feb 7 after she was exposed to backyard poultry.
Both kids recovered after mild illnesses and so far no family clusters have been reported.
Elsewhere, Cambodia reported a H9N2 infection on Apr 2 in a 3-year-old boy, according to an avian influenza update from Hong Kong's Centre for Health Protection (CHP).
So far this year, the WHO's Western Pacific region has reported 12 H9N2 cases, mostly from China. The virus isn't unusual in poultry, and sporadic human infections?which are most common in children?continue to be detected, but with no sustained transmission.
Apr 16 WHO Western Pacific regional office update
Apr 20 Hong Kong CHP report
News Scan for Apr 21, 2021
Colistin resistance in Enterobacterales; H9N2 flu in China, Cambodia
Filed Under:
Avian Influenza (Bird Flu); Antimicrobial Stewardship
Risk factors, mechanisms noted in colistin-resistant Enterobacterales
A study of colistin-resistant Enterobacterales (CORE) isolates from patients in southeast Michigan found that increased age and prior antibiotic receipt were associated with increased risk of CORE colonization or infection, researchers reported today in Open Forum Infectious Diseases.
In the study, one of the first to provide large-scale colistin resistance data on clinical Enterobacterales isolates in the United States, researchers with the University of Michigan and Case Western Reserve University examined routine clinical isolates obtained in single tertiary health system in Ann Arbor from January 2016 through March 2017.
Patients with CORE isolates were matched 1:1 with patients with colistin-susceptible Enterobacterales (COSE) isolates and uninfected control patients, and multivariable logistics regression was used to compare clinical and microbiologic features. The researchers also conducted whole-genome sequencing (WGS) on a subset of CORE isolates.
Of 16,373 tested clinical isolates, 166 (0.99%) were colistin-resistant, representing 103 unique patients. CORE specimens included 45 Enterobacter isolates, 31 Escherichia coli isolates, and 27 Klebsiella pneumoniae isolates. Multivariable analysis of 103 CORE isolates, 103 COSE isolates, and 102 uninfected controls found that antibiotic exposure in the prior 90 days (odds ratio [OR], 2.22; 95% confidence interval [CI], 1.23 to 4.03) and being age 55 and older (OR, 4.06; 95% CI, 2.24 to 7.36) were predictors of CORE. But notably, none of the 103 patients with CORE were exposed to colistin before culture collection. The same factors were also predictors of COSE.
Among the 33 isolates that underwent WGS, several genetic mutations associated with colistin resistance were found; three MCR-1 genes, one MCR-1.1 gene, and four pmrA/B mutations were identified in E coli isolates, and 5 mgrB and pmrA mutations were detected on K pneumoniae isolates. Mechanisms of colistin resistance among Enterobacter isolates could not be determined.
"Further studies are needed to determine the drivers of and determinants of polymyxin resistance among Enterobacterales, including exposure to non-polymyxin antimicrobials," the authors concluded.
Apr 21 Open Forum Infect Dis abstract
H9N2 avian flu virus infects kids in China, Cambodia
China has reported two more H9N2 avian flu infections in humans, both involving children who are from two different provinces, the World Health Organization (WHO) Western Pacific regional office said in its most recent avian influenza update.
One of the patients is a 10-year-old boy from Fujian province whose symptoms began on Feb 28. The investigation found no history of exposure to poultry. The other is a 2-year-old girl from Hubei province who got sick on Feb 7 after she was exposed to backyard poultry.
Both kids recovered after mild illnesses and so far no family clusters have been reported.
Elsewhere, Cambodia reported a H9N2 infection on Apr 2 in a 3-year-old boy, according to an avian influenza update from Hong Kong's Centre for Health Protection (CHP).
So far this year, the WHO's Western Pacific region has reported 12 H9N2 cases, mostly from China. The virus isn't unusual in poultry, and sporadic human infections?which are most common in children?continue to be detected, but with no sustained transmission.
Apr 16 WHO Western Pacific regional office update
Apr 20 Hong Kong CHP report