Simultaneous emergence and rapid spread of three OXA-23 producing Acinetobacter baumannii ST208 strains in intensive care units confirmed by whole genome sequencing

2018 ◽  
Vol 58 ◽  
pp. 243-250 ◽  
Author(s):  
Qiong Chen ◽  
Jia-wei Zhou ◽  
Jian-zhong Fan ◽  
Sheng-hai Wu ◽  
Li-hui Xu ◽  
...  
2019 ◽  
Vol 14 (15) ◽  
pp. 1281-1292 ◽  
Author(s):  
Giovanni Lorenzin ◽  
Erika Scaltriti ◽  
Franco Gargiulo ◽  
Francesca Caccuri ◽  
Giorgio Piccinelli ◽  
...  

Aim: This study aims to characterize clinical strains of Acinetobacter baumannii with an extensively drug-resistant phenotype. Methods: VITEK® 2, Etest® method and broth microdilution method for colistin were used. PCR analysis and multilocus sequence typing Pasteur scheme were performed to identify bla-OXA genes and genetic relatedness, respectively. Whole-genome sequencing analysis was used to characterize three isolates. Results: All the isolates were susceptible only to polymyxins. blaOXA-23-like gene was the only acquired carbapenemase gene in 88.2% of the isolates. Multilocus sequence typing identified various sequence types: ST2, ST19, ST195, ST577 and ST632. Two new sequence types, namely, ST1279 and ST1280, were detected by whole-genome sequencing. Conclusion: This study showed that carbapenem-resistant A. baumannii isolates causing infections in intensive care units almost exclusively produce OXA-23, underlining their frequent spread in Italy.


2017 ◽  
Author(s):  
Josh E. Petrikin ◽  
Julie A. Cakici ◽  
Michelle M. Clark ◽  
Laurel K. Willig ◽  
Nathaly M. Sweeney ◽  
...  

AbstractImportanceGenetic disorders, including congenital anomalies, are a leading cause of morbidity and mortality in infants, especially in neonatal and pediatric intensive care units (NICU and PICU). While genomic sequencing is useful for diagnosis of genetic diseases, results are usually reported too late to guide inpatient management.ObjectiveTo test the hypothesis that rapid whole genome sequencing (rWGS) increases the proportion of infants in NICUs and PICUs receiving a genetic diagnosis within 28 days.DesignAn investigator-initiated, partially blinded, pragmatic, randomized controlled study with enrollment from October 2014 - June 2016, and follow up until December 2016.SettingA regional neonatal and pediatric intensive care unit in a tertiary referral childrens hospital.ParticipantsSixty five of 129 screened families with infants aged less than four months, in neonatal and pediatric intensive care units, and with illnesses of unknown etiology, completed the study.InterventionParent and infant trio rWGS.Main Outcome and MeasureThe hypothesis and end-points were formulated a priori. The primary end-point was rate of genetic diagnosis within 28 days of enrollment or first standard test order.ResultsTwenty six female proband infants, 37 male infants, and two infants of undetermined sex were randomized to receive rWGS plus standard tests (n=32, cases) or standard tests alone (n=33, controls). The study was terminated early due to loss of equipoise: 63% (21) controls received genomic sequencing as standard tests. Nevertheless, intention to treat analysis showed the rate of genetic diagnosis within 28 days to be higher in cases (31%, ten of 32) than controls (3%, one of 33; difference, 28% [95% CI, 10% to 46%]; p=0.003). Among infants enrolled in the first 25 days of life, the rate of neonatal diagnosis was higher in cases (32%, seven of 22) than controls (0%, zero of 23; difference, 32% [95% CI, 11% to 53%]; p=0.004). Age at diagnosis (median in cases 25 days, range 14-90 days vs median in controls 130 days, range 37-451) and time to diagnosis (median in cases thirteen days, range 1-84 days vs median in controls 107 days, range 21-429 days) were significantly less in cases than controls (p=0.04).CONCLUSIONSrWGS increased the proportion of infants in a regional NICU and PICU who received a timely diagnosis of a genetic disease. Additional, adequately powered studies are needed to determine whether accelerated diagnosis is associated with improved outcomes in this setting. ClinicalTrials.gov Identifier: NCT02225522.


2019 ◽  
Vol 6 (Supplement_2) ◽  
pp. S852-S852
Author(s):  
Erica S Shenoy ◽  
Virginia M Pierce ◽  
Mohamad Sater ◽  
Febriana Pangestu ◽  
Ian Herriott ◽  
...  

Abstract Background Detection of nosocomial outbreaks often relies on epidemiological definitions of community and nosocomial acquisition. We report a cluster of three carbapenem-resistant Acinetobacter baumannii (CRAB) infections linked to a single source patient with infections occurring within 2 days of admission to a burn intensive care unit (ICU). The epidemiological investigation was supplemented by whole-genome sequencing (WGS) of clinical and environmental isolates. Methods Study participants included burn ICU patients identified with infections caused by CRAB. A detailed review of patient demographic and clinical data was conducted. Clinical A. baumannii isolates were assessed by antimicrobial susceptibility testing and WGS. Review of infection control practices on the affected unit was followed by environmental sampling. A. baumannii isolates obtained through environmental sampling were assessed for carbapenem resistance and then underwent WGS for comparison to the clinical isolates. Results Three cases of CRAB infection in the affected unit spanning a period of 3 months were linked to a preceding source patient, with CRAB isolates from the four patients differing by 5–7 single nucleotide variations. All case patients had been admitted to the same room within 2 days before development of CRAB infection. Environmental sampling performed while the third case patient occupied the room identified highly contaminated areas, and environmental CRAB isolates linked the patient isolates. The contaminated areas were subsequently re-sampled after enhanced terminal cleaning of the room. No additional CRAB was isolated, but other pathogenic organisms were recovered. Conclusion We report a cluster of three infections caused by highly resistant A. baumannii that occurred in a burn intensive care unit over a period of 3 months, linked to a single source patient. Three case patients developed infections classified as community-acquired using standard epidemiological definitions, however, whole-genome sequencing revealed clonality. An extensive investigation identified the role of environmental reservoirs. Burn patients may be particularly vulnerable to early-onset nosocomial infection from environmental contamination. Disclosures All authors: No reported disclosures.


2012 ◽  
Vol 4 (154) ◽  
pp. 154ra135-154ra135 ◽  
Author(s):  
C. J. Saunders ◽  
N. A. Miller ◽  
S. E. Soden ◽  
D. L. Dinwiddie ◽  
A. Noll ◽  
...  

2021 ◽  
Vol 12 ◽  
Author(s):  
Pu Mao ◽  
Xiaolong Deng ◽  
Leping Yan ◽  
Ya Wang ◽  
Yueting Jiang ◽  
...  

The nosocomial pathogen Acinetobacter baumannii is a frequent cause of healthcare-acquired infections, particularly in critically ill patients, and is of serious concern due to its potential for acquired multidrug resistance. Whole-genome sequencing (WGS) is increasingly used to obtain a high-resolution view of relationships between isolates, which helps in controlling healthcare-acquired infections. Here, we conducted a retrospective study to identify epidemic situations and assess the percentage of transmission in intensive care units (ICUs). Multidrug-resistant A. baumannii (MDR-AB) were continuously isolated from the lower respiratory tract of different patients (at the first isolation in our ICU). We performed WGS, pulsed-field gel electrophoresis (PFGE), and multilocus-sequence typing (MLST) analyses to elucidate bacterial relatedness and to compare the performance of conventional methods with WGS for typing MDR-AB. From June 2017 to August 2018, A. baumannii complex strains were detected in 124 of 796 patients during their ICU stays, 103 of which were MDR-AB. Then we subjected 70 available MDR-AB strains to typing with WGS, PFGE, and MLST. Among the 70 A. baumannii isolates, 38 (54.29%) were isolated at admission, and 32(45.71%) were acquisition isolates. MLST identified 12 unique sequence types, a novel ST (ST2367) was founded. PFGE revealed 16 different pulsotypes. Finally, 38 genotypes and 23 transmissions were identified by WGS. Transmission was the main mode of MDR-AB acquisition in our ICU. Our results demonstrated that WGS was a discriminatory technique for epidemiological healthcare-infection studies. The technique should greatly benefit the identification of epidemic situations and controlling transmission events in the near future.


Diagnostics ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 201
Author(s):  
Sang Mee Hwang ◽  
Hee Won Cho ◽  
Tae Yeul Kim ◽  
Jeong Su Park ◽  
Jongtak Jung ◽  
...  

Carbapenem-resistant Acinetobacter baumannii (CRAB) outbreaks in hospital settings challenge the treatment of patients and infection control. Understanding the relatedness of clinical isolates is important in distinguishing outbreak isolates from sporadic cases. This study investigated 11 CRAB isolates from a hospital outbreak by whole-genome sequencing (WGS), utilizing various bioinformatics tools for outbreak analysis. The results of multilocus sequence typing (MLST), single nucleotide polymorphism (SNP) analysis, and phylogenetic tree analysis by WGS through web-based tools were compared, and repetitive element polymerase chain reaction (rep-PCR) typing was performed. Through the WGS of 11 A. baumannii isolates, three clonal lineages were identified from the outbreak. The coexistence of blaOXA-23, blaOXA-66, blaADC-25, and armA with additional aminoglycoside-inactivating enzymes, predicted to confer multidrug resistance, was identified in all isolates. The MLST Oxford scheme identified three types (ST191, ST369, and ST451), and, through whole-genome MLST and whole-genome SNP analyses, different clones were found to exist within the MLST types. wgSNP showed the highest discriminatory power with the lowest similarities among the isolates. Using the various bioinformatics tools for WGS, CRAB outbreak analysis was applicable and identified three discrete clusters differentiating the separate epidemiologic relationships among the isolates.


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