Our weekly wrap-up of antimicrobial stewardship & antimicrobial resistance scans
Study describes outbreak of highly resistant, deadly Klebsiella in India
Indian researchers yesterday reported on a hospital outbreak of two strains of extensively drug-resistant Klebsiella pneumoniae. Their findings appeared in Antimicrobial Resistance and Infection Control.
The outbreak in the tertiary care hospital in Varanasi, India, was first identified between April and June, 2017, when a sudden surge of neonatal sepsis cases caused by K pneumoniae occurred in the hospital's neonatal intensive care unit (NICU); twelve of the 14 infants died. Subsequent environmental surveillance uncovered K pneumoniae in the hand-wash used in the NICU, and in the wash basin in the labor room. Further investigation revealed an adult infected with K pneumonia on Apr 3 in the intensive care unit (ICU) was the hospital's primary case. An additional 18 K pneumoniae infections were reported in the ICU until July 2017.
Analysis of 45 K pneumoniae isolates from the ICU, NICU, other wards, and the hospital environment found all of the NICU isolates and 94.4% of the ICU isolates were resistant to all tested antibiotics, including colistin and carbapenems. More than half of the isolates carried a combination of extended-spectrum beta-lactamase and carbapenemase genes. Clonal typing found two distinct sequence types, ST5235 and ST5313, with ST5235 predominantly found in the NICU.
The outbreak was contained through strengthening of infection control procedures and an unrelated hospital closure. No further cases were identified after Jul 6, 2017.
The study authors say the findings highlight concerns about the rising use of colistin and poor infection control measures in Indian hospitals, and call for the global impact of ST5235 and ST5315 to be further studied.
Jan 6 Antimicrob Resist Infect Control study
Trial finds three rounds of azithromycin better than one for yaws reduction
Originally published by CIDRAP News Jan 6
The results of a randomized trial in Papua New Guinea suggest three rounds of mass administration of azithromycin led to a greater reduction in the prevalence of yaws than a single round, researchers reported today in the New England Journal of Medicine.
In the community-based, open-label trial, conducted in an area of Papua New Guinea where yaws—an infection of the skin, bone, and cartilage caused by the bacterium Treponema pallidum subspecies pertenue—is endemic, an international team of investigators randomly assigned more than 56,000 villagers in 38 wards to receive one round of mass administration of azithromycin (the control group) or three rounds at 6-month intervals (the experimental group). The current World Health Organization strategy for eradicating yaws by 2030 involves one round of azithromycin followed by active case detection surveys and targeted treatment every 6 months, but previous studies in Papua New Guinea, the Solomon Islands, and Ghana have found that this strategy has not been enough to stop transmission.
The coprimary endpoints of the trial, conducted from April 2018 through October 2019, were the prevalence of active yaws cases in the two groups at 18 months, and the prevalence of latent yaws in a subgroup of asymptomatic children.
At 18 months, the prevalence of active yaws had decreased from 0.46% (102 of 22,033 people) to 0.16% (47 of 29,954) in the control group, and 0.43% (87 of 20,331) to 0.04% (10 of 25,987) in the experimental group (relative risk adjusted for clustering, 4.08; 95% confidence interval [CI], 1.90 to 8.76). The prevalence of latent yaws at 18 months was 6.54% among 994 children in the control group and 3.28% in the experimental group (relative risk adjusted for clustering of age, 2.03; 95% CI, 1.12 to 3.70). Molecular analysis of three cases of yaws found mutations associated with macrolide resistance.
"Our data suggest more than one round of mass drug administration should be considered as part of the strategy for yaws eradication," the authors write. But they caution that the failure to completely eliminate yaws, and the finding of resistance mutations, highlight the need for further clinical and molecular surveillance for the emergence of antimicrobial resistance.
Jan 6 N Engl J Med study
High mortality persists for Candida bloodstream infections
Originally published by CIDRAP News Jan 6
Bloodstream infections (BSIs) caused by Candida species were associated with a more than two-fold increased risk of mortality, researchers reported yesterday in Clinical Infectious Diseases.
The single-center study by researchers with Washington University in St. Louis School of Medicine, frequency-matched 626 adult patients with Candida BSIs with 6,269 control patients who had at least one risk factor for Candida BSI but did not develop one. They calculated 90-day all-cause mortality attributable to Candida BSI using propensity score matching, matching by inverse-weighting of propensity score, and stratified analysis by quintile.
The 90-day crude all-cause mortality for patients with Candida BSI was 42.4%, compared with 17.1% for the frequency-matched controls, with a crude mortality rate difference of 25.3%. In the propensity-scored matched pairs analysis, the hazard ratio (HR) for 90-day all-cause mortality associated with Candida BSI was 2.1 (95% CI, 2.0 to 2.3), with an attributable risk difference of 28.4%. In the analysis using inverse-weighting by the propensity score, the HR for 90-day all-cause mortality associated with Candida BSI was 2.1 (95%, 2.0 to 2.3).
In the stratified analysis, the risk for mortality at 90 days was highest in patients in the lowest risk quintile to develop Candida BSI (HR, 3.13; 95% CI, 2.33 to 4.19), a finding the researchers attribute to a higher proportion of these low-risk patients going untreated.
"Overall, Candida BSI was associated with 2.3-fold increased risk of 90-day all-cause mortality," the study authors wrote. "High mortality observed has persisted over decades despite treatment advances, though mortality attributable to Candida BSI has decreased compared to most historical studies. It is imperative that clinicians maximize efforts to adhere to guideline recommendations and seek Infectious Disease consultation to assist in timely, efficacious treatment of Candida BSI."
Jan 5 Clin Infect Dis abstract
Candida auris infections identified in Oregon
Originally published by CIDRAP News Jan 3
The Oregon Health Authority (OHA) announced last week that it's investigating the state's first cases of the multidrug-resistant fungus Candida auris.
The C auris cases were identified in three Salem Health patients. The first case was identified on Dec 11 in a patient who had recent international healthcare exposure, and the second and third cases had no international healthcare exposure but were epidemiologically linked to the first case, indicating healthcare-associated spread.
Salem Health officials say the infections appear to be responding to current treatments and that the hospital is working with OHA, local public health partners, and the CDC to identify additional cases and ensure appropriate infection control procedures are in place.
"Salem Health is working with OHA and the CDC to execute a rigorous plan, implementing aggressive eradication measures that have been shown in other hospitals to be successful in eliminating Candida auris," Jasmin Chaudhary, MD, Salem Health's medical director of infection prevention, said in an OHA press release. "These include proactive steps that will assist in preemptively identifying new cases to prevent spread."
In its most recent update, the CDC reported a total of 938 confirmed C auris infections in 21 states from September 2020 through August 2021, along with 3,034 patients colonized with the organism. The multidrug-resistant yeast, which spreads easily in healthcare settings and can cause severe and deadly invasive infections in immunocompromised patients, was first identified in Japan in 2009 and first appeared in the United States in 2013.
Dec 28 OHA press release
Oct 27 CDC Candida auris update