blaVIM- and blaOXA-mediated carbapenem resistance among Acinetobacter baumannii and Pseudomonas aeruginosa isolates from the Mulago hospital intensive care unit in Kampala, Uganda

Abstract Background Between January 2015 and July 2017, we investigated the frequency of carbapenem resistant Acinetobacter baumannii (CRAB) and carbapenem resistant Pseudomonas aeruginosa (CRPA) at the Mulago Hospital intensive care unit (ICU) in Kampala, Uganda. Carbapenemase production and carbapenemase gene carriage among CRAB and CRPA were determined; mobility potential of carbapenemase genes via horizontal gene transfer processes was also studied. Methods Clinical specimens from 9269 patients were processed for isolation of CRAB and CRPA. Drug susceptibility testing was performed with the disk diffusion method. Carriage of carbapenemase genes and class 1 integrons was determined by PCR. Conjugation experiments that involved blaVIM positive CRAB/CRPA (donors) and sodium azide resistant Escherichia coli J53 (recipient) were performed. Results The 9269 specimens processed yielded 1077 and 488 isolates of Acinetobacter baumannii and Pseudomonas aeruginosa, respectively. Of these, 2.7% (29/1077) and 7.4% (36/488) were confirmed to be CRAB and CRPA respectively, but 46 were available for analysis (21 CRAB and 25 CRPA). Majority of specimens yielding CRAB and CRPA were from the ICU (78%) while 20 and 2% were from the ENT (Ear Nose & Throat) Department and the Burns Unit, respectively. Carbapenemase assays performed with the MHT assay showed that 40 and 33% of CRPA and CRAB isolates respectively, were carbapenemase producers. Also, 72 and 48% of CRPA and CRAB isolates respectively, were metallo-beta-lactamase producers. All the carbapenemase producing isolates were multidrug resistant but susceptible to colistin. blaVIM was the most prevalent carbapenemase gene, and it was detected in all CRAB and CRPA isolates while blaOXA-23 and blaOXA-24 were detected in 29 and 24% of CRAB isolates, respectively. Co-carriage of blaOXA-23 and blaOXA-24 occurred in 14% of CRAB isolates. Moreover, 63% of the study isolates carried class 1 integrons; of these 31% successfully transferred blaVIM to E. coli J53. Conclusions CRAB and CRPA prevalence at the Mulago Hospital ICU is relatively low but carbapenemase genes especially blaVIM and blaOXA-23 are prevalent among them. This requires strengthening of infection control practices to curb selection and transmission of these strains in the hospital.

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Outbreak of NDM-1-producing Acinetobacter baumannii in France, January to May 2013

Eurosurveillance ◽

10.2807/1560-7917.es2013.18.31.20547 ◽

2013 ◽

Vol 18 (31) ◽

Cited By ~ 29

Author(s):

J W Decousser ◽

C Jansen ◽

P Nordmann ◽

A Emirian ◽

R A Bonnin ◽

...

Keyword(s):

Intensive Care Unit ◽

Intensive Care ◽

Acinetobacter Baumannii ◽

Index Patient ◽

Imported Case ◽

Carbapenem Resistant ◽

Carbapenemase Gene

We report the first outbreak of carbapenem-resistant NDM-1-producing Acinetobacter baumannii in Europe, in a French intensive-care unit in January to May 2013. The index patient was transferred from Algeria and led to the infection/colonisation of five additional patients. Concurrently, another imported case from Algeria was identified. The seven isolates were genetically indistinguishable, belonging to ST85. The blaNDM-1 carbapenemase gene was part of the chromosomally located composite transposon Tn125. This report underscores the growing concern about the spread of NDM-1-producing A. baumannii in Europe.

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Molecular Characterization of Carbapenem-Resistant Acinetobacter baumannii Isolated from the Intensive Care Unit in a Tertiary Teaching Hospital in Malaysia

Antibiotics ◽

10.3390/antibiotics10111340 ◽

2021 ◽

Vol 10 (11) ◽

pp. 1340

Author(s):

Jia Jie Woon ◽

Cindy Shuan Ju Teh ◽

Chun Wie Chong ◽

Kartini Abdul Jabar ◽

Sasheela Ponnampalavanar ◽

...

Keyword(s):

Intensive Care Unit ◽

Intensive Care ◽

Acinetobacter Baumannii ◽

Molecular Characterization ◽

Univariate Analysis ◽

Control Measures ◽

High Rate ◽

Carbapenem Resistant ◽

Tertiary Teaching ◽

Carbapenemase Gene

The emergence of carbapenem-resistant Acinetobacter baumannii (CRAB) has now become a global sentinel event. CRAB infections often instigate severe clinical complications and are potentially fatal, especially for debilitated patients. The present study aimed to conduct molecular characterization on CRAB isolated from patients in the intensive care unit from 2015 to 2016 and determine the risk factors associated with patients’ mortality. One hundred CRAB isolates were retrospectively selected and included in this study. Antimicrobial susceptibility testing showed that all isolates remained susceptible to colistin, even though 62% of them conferred resistance to all other classes of antibiotics tested. OXA carbapenemase gene was found to be the predominant carbapenemase gene, with 99% of the isolates coharbouring blaOXA-23-like and blaOXA-51-like carbapenemase genes. All isolates were carrying intact CarO genes, with the presence of various degree of nucleotide insertion, deletion and substitution. Overall, PFGE subtyped the isolates into 13 distinct pulsotypes, with the presence of 2 predominant pulsotypes. Univariate analysis implied that age, infection/colonization by CRAB, ethnicity, comorbidity and CRAB specimen source were significantly associated with in-hospital mortality. Multivariate analysis identified a higher risk of mortality for patients who are of Chinese ethnicity with diabetes as an underlying disease. As CRAB infection could lead to high rate of mortality, comprehensive infection control measures are needed to minimize the spread of this pathogen.

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Genetic Context and Structural Diversity of Class 1 Integrons from Human Commensal Bacteria in a Hospital Intensive Care Unit

Antimicrobial Agents and Chemotherapy ◽

10.1128/aac.01831-10 ◽

2011 ◽

Vol 55 (8) ◽

pp. 3939-3943 ◽

Cited By ~ 22

Author(s):

Thu Betteridge ◽

Sally R. Partridge ◽

Jonathan R. Iredell ◽

H. W. Stokes

Keyword(s):

Intensive Care Unit ◽

Intensive Care ◽

Structural Diversity ◽

Pcr Screening ◽

Class 1 Integrons ◽

Conserved Regions ◽

Hospital Intensive Care Unit ◽

Class 1 ◽

Additional Level ◽

Genetic Context

ABSTRACTMost surveys for class 1 integrons are at least partly predicated on PCR screening that targets integron conserved regions. However, class 1 integrons are structurally diverse, so dependence on conserved regions may lead to missing clinically relevant examples of class 1 integrons. Here, we surveyed a commensal population of bacteria from patients in an intensive care unit to identify class 1 integrons irrespective of their structure or genetic context. We identified several examples of class 1 integrons linked to complete Tn402-like or Tn402hybrid transposition modules and diverse insertion points with respect to the inverted repeat IRi boundary. The diversity and abundance of class 1 integrons identified are such that many novel elements seen here would not have been identified by commonly used methods, and they revealed an additional level of complexity.

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