Shiloh
Editor, Senior Moderator
Source: http://www.cidrap.umn.edu/news-perspective/2019/10/stewardship-resistance-scan-oct-24-2019
Stewardship / Resistance Scan for Oct 24, 2019
Colistin-resistant K pneumoniae in India; Transmissibility of MDR-TB
Filed Under:
Antimicrobial Stewardship; Tuberculosis
[h=3]Colistin-resistant Klebsiella infections documented at Indian hospital[/h] A new study in Infection Control and Hospital Epidemiology describes several cases of colistin-resistant Klebsiella pneumoniae infections at a hospital in northern India.
The retrospective study, conducted by researchers from India and the US Centers for Disease Control and Prevention (CDC), focuses on 22 patients at the All India Institute of Medical Sciences in New Delhi who were diagnosed with colistin-resistant K pneumoniae infections from January 2016 through October 2017. The patients were identified as part of an investigation that aimed to determine the extent of colistin-resistance in K pneumonia isolates at the hospital, describe patient characteristics, and characterize transmission dynamics. The high prevalence of carbapenem resistance in gram-negative bacteria in India has led to increasing use of colistin, and recent reports have documented the identification of colistin-resistant K pneumonia in Indian hospitals.
Of the 22 patients, 16 had undergone a surgical procedure prior to the infection, and 7 had a history of exposure to colistin. Ten of the patients died. The 34 isolates collected from the patients represented 4% of all K pneumoniae isolates collected during the study period. Analysis of the isolates found that 100% were multidrug-resistant and 68% were extensively drug resistant; in addition to colistin, all isolates were resistant to carbapenems, extended-spectrum cephalosporins, and penicillin/beta-lactam inhibitors.
Whole-genome sequencing revealed the presence of several carbapenemase genes in the isolates, but no MCR genes. Colistin resistance was attributed to several chromosomal mutations. Sequencing also revealed 8 unique multilocus sequence types (STs), the most common being ST231 (5 isolates), ST11 (4 isolates), and ST14 (4 isolates) — these are well-documented multidrug-resistant K pneumoniae strains that have caused hospital outbreaks in Europe and Asia.
The authors of the study note that half of the patients had been transferred from other facilities, which suggests colistin-resistant K pneumoniae may be widely distributed in other hospitals in India.
"Action is needed from a broad range of stakeholders, including clinicians, microbiologists, and public health officials, to limit the spread of this critically important MDRO (multidrug-resistant organism)," the authors write.
Oct 18 Infect Control Hosp Epidemiol abstract
[h=3]Peruvian study finds MDR-TB just as transmissible as drug-sensitive TB[/h] A study conducted in Peru has found that household contacts of patients with multidrug-resistant tuberculosis (MDR-TB) were at higher risk of TB infection than contacts exposed to patients with drug-sensitive TB, and had a similar risk of developing active disease, US and Peruvian researchers reported today in BMJ.
From September 2009 through September 2012, the researchers enrolled 3,339 index patients from health centers in Lima who had microbiologically confirmed TB disease, and 10,160 household contacts. Of those contacts, 6,189 were exposed to drug-sensitive strains of Mycobacterium tuberculosis, 1,659 to strains that were resistant to isoniazid or rifampicin, and 1,541 to MDR-TB strains (resistant to isoniazid and rifampicin). The main outcomes of the study were TB infection and incidence of active disease among household contacts after 12 months of follow-up.
The results showed that contacts of MDR-TB index patients had an 8% (95% confidence interval [CI], 4% to 13%) higher risk of TB infection by the end of follow-up compared with contacts exposed to drug-sensitive TB patients. The relative hazard of incident TB disease did not differ among contacts exposed to MDR-TB compared with those exposed to drug-sensitive TB (adjusted hazard ratio, 1.28; 95% CI, 0.9 to 1.83).
The authors of the study say the results are significant for TB control efforts because they suggest that there is no fitness cost associated with drug resistance in M tuberculosis.
"If M tuberculosis drug resistance exacts no fitness cost, the incidence of drug resistant and multidrug resistant tuberculosis will be expected to fall more slowly than would be expected," they write.
They add, "Our findings provide evidence that invites guideline producers to take action by targeting drug resistant and multidrug resistant tuberculosis, such as the early detection and effective treatment of infection and disease. These guidelines should include the wider deployment of existing tools and the development of diagnostic and therapeutic strategies designed specifically for people already infected with drug resistant tuberculosis."
Oct 24 BMJ study
Stewardship / Resistance Scan for Oct 24, 2019
Colistin-resistant K pneumoniae in India; Transmissibility of MDR-TB
Filed Under:
Antimicrobial Stewardship; Tuberculosis
[h=3]Colistin-resistant Klebsiella infections documented at Indian hospital[/h] A new study in Infection Control and Hospital Epidemiology describes several cases of colistin-resistant Klebsiella pneumoniae infections at a hospital in northern India.
The retrospective study, conducted by researchers from India and the US Centers for Disease Control and Prevention (CDC), focuses on 22 patients at the All India Institute of Medical Sciences in New Delhi who were diagnosed with colistin-resistant K pneumoniae infections from January 2016 through October 2017. The patients were identified as part of an investigation that aimed to determine the extent of colistin-resistance in K pneumonia isolates at the hospital, describe patient characteristics, and characterize transmission dynamics. The high prevalence of carbapenem resistance in gram-negative bacteria in India has led to increasing use of colistin, and recent reports have documented the identification of colistin-resistant K pneumonia in Indian hospitals.
Of the 22 patients, 16 had undergone a surgical procedure prior to the infection, and 7 had a history of exposure to colistin. Ten of the patients died. The 34 isolates collected from the patients represented 4% of all K pneumoniae isolates collected during the study period. Analysis of the isolates found that 100% were multidrug-resistant and 68% were extensively drug resistant; in addition to colistin, all isolates were resistant to carbapenems, extended-spectrum cephalosporins, and penicillin/beta-lactam inhibitors.
Whole-genome sequencing revealed the presence of several carbapenemase genes in the isolates, but no MCR genes. Colistin resistance was attributed to several chromosomal mutations. Sequencing also revealed 8 unique multilocus sequence types (STs), the most common being ST231 (5 isolates), ST11 (4 isolates), and ST14 (4 isolates) — these are well-documented multidrug-resistant K pneumoniae strains that have caused hospital outbreaks in Europe and Asia.
The authors of the study note that half of the patients had been transferred from other facilities, which suggests colistin-resistant K pneumoniae may be widely distributed in other hospitals in India.
"Action is needed from a broad range of stakeholders, including clinicians, microbiologists, and public health officials, to limit the spread of this critically important MDRO (multidrug-resistant organism)," the authors write.
Oct 18 Infect Control Hosp Epidemiol abstract
[h=3]Peruvian study finds MDR-TB just as transmissible as drug-sensitive TB[/h] A study conducted in Peru has found that household contacts of patients with multidrug-resistant tuberculosis (MDR-TB) were at higher risk of TB infection than contacts exposed to patients with drug-sensitive TB, and had a similar risk of developing active disease, US and Peruvian researchers reported today in BMJ.
From September 2009 through September 2012, the researchers enrolled 3,339 index patients from health centers in Lima who had microbiologically confirmed TB disease, and 10,160 household contacts. Of those contacts, 6,189 were exposed to drug-sensitive strains of Mycobacterium tuberculosis, 1,659 to strains that were resistant to isoniazid or rifampicin, and 1,541 to MDR-TB strains (resistant to isoniazid and rifampicin). The main outcomes of the study were TB infection and incidence of active disease among household contacts after 12 months of follow-up.
The results showed that contacts of MDR-TB index patients had an 8% (95% confidence interval [CI], 4% to 13%) higher risk of TB infection by the end of follow-up compared with contacts exposed to drug-sensitive TB patients. The relative hazard of incident TB disease did not differ among contacts exposed to MDR-TB compared with those exposed to drug-sensitive TB (adjusted hazard ratio, 1.28; 95% CI, 0.9 to 1.83).
The authors of the study say the results are significant for TB control efforts because they suggest that there is no fitness cost associated with drug resistance in M tuberculosis.
"If M tuberculosis drug resistance exacts no fitness cost, the incidence of drug resistant and multidrug resistant tuberculosis will be expected to fall more slowly than would be expected," they write.
They add, "Our findings provide evidence that invites guideline producers to take action by targeting drug resistant and multidrug resistant tuberculosis, such as the early detection and effective treatment of infection and disease. These guidelines should include the wider deployment of existing tools and the development of diagnostic and therapeutic strategies designed specifically for people already infected with drug resistant tuberculosis."
Oct 24 BMJ study