Dataset Information

ICU-associated Acinetobacter baumannii colonisation/infection in a high HIV-prevalence resource-poor setting.

ABSTRACT:

Background

There are hardly any data about the incidence, risk factors and outcomes of ICU-associated A.baumannii colonisation/infection in HIV-infected and uninfected persons from resource-poor settings like Africa.

Methods

We reviewed the case records of patients with A.baumannii colonisation/infection admitted into the adult respiratory and surgical ICUs in Cape Town, South Africa, from January 1 to December 31 2008. In contrast to colonisation, infection was defined as isolation of A.baumannii from any biological site in conjunction with a compatible clinical picture warranting treatment with antibiotics effective against A.baumannii.

Results

The incidence of A.baumannii colonisation/infection in 268 patients was 15 per 100 person-years, with an in-ICU mortality of 26.5 per 100 person-years. The average length of stay in ICU was 15 days (range 1-150). A.baumannii was most commonly isolated from the respiratory tract followed by the bloodstream. Independent predictors of mortality included older age (p?=?0.02), low CD4 count if HIV-infected (p?=?0.038), surgical intervention (p?=?0.047), co-morbid Gram-negative sepsis (p?=?0.01), high APACHE-II score (p?=?0.001), multi-organ dysfunction syndrome (p?=?0.012), and a positive blood culture for A.baumannii (p?=?0.017). Of 21 A.baumannii colonised/infected HIV-positive persons those with clinical AIDS (CD4<200 cells/mm(3)) had significantly higher in-ICU mortality and were more likely to have a positive blood culture. Conclusion In this resource-poor setting A.baumannii infection in critically ill patients is common and associated with high mortality. HIV co-infected patients with advanced immunosuppression are at higher risk of death.

SUBMITTER: Ntusi NB

PROVIDER: S-EPMC3531465 | biostudies-literature | 2012

REPOSITORIES: biostudies-literature

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Publications

ICU-associated Acinetobacter baumannii colonisation/infection in a high HIV-prevalence resource-poor setting.

Ntusi Ntobeko B A NB Badri Motasim M Khalfey Hoosain H Whitelaw Andrew A Oliver Stephen S Piercy Jenna J Raine Richard R Joubert Ivan I Dheda Keertan K

PloS one 20121227 12

<h4>Background</h4>There are hardly any data about the incidence, risk factors and outcomes of ICU-associated A.baumannii colonisation/infection in HIV-infected and uninfected persons from resource-poor settings like Africa.<h4>Methods</h4>We reviewed the case records of patients with A.baumannii colonisation/infection admitted into the adult respiratory and surgical ICUs in Cape Town, South Africa, from January 1 to December 31 2008. In contrast to colonisation, infection was defined as isolati ...[more]

PMID: 23300673

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Project description:Acinetobacter baumannii causes severe, fulminant, community-acquired pneumonia (CAP) in tropical and subtropical regions. We compared the population structure, virulence and antimicrobial resistance determinants of northern Australian community-onset A. baumannii strains with local and global strains. We performed whole-genome sequencing on 55 clinical and five throat colonization A. baumannii isolates collected in northern Australia between 1994 and 2016. Clinical isolates included CAP (n=41), healthcare-associated pneumonia (n=7) and nosocomial bloodstream (n=7) isolates. We also included 93 publicly available international A. baumannii genome sequences in the analyses. Patients with A. baumannii CAP were almost all critically unwell; 82 % required intensive care unit admission and 18 % died during their inpatient stay. Whole-genome phylogenetic analysis demonstrated that community-onset strains were not phylogenetically distinct from nosocomial strains. Some non-multidrug-resistant local strains were closely related to multidrug-resistant strains from geographically distant locations. Pasteur sequence type (ST)10 was the dominant ST and accounted for 31/60 (52 %) northern Australian strains; the remainder belonged to a diverse range of STs. The most recent common ancestor for ST10 was estimated to have occurred in 1738 (95 % highest posterior density, 1626-1826), with evidence of multiple introduction events between Australia and Southeast Asia between then and the present day. Virulence genes associated with biofilm formation and the type 6 secretion system (T6SS) were absent in many strains, and were not associated with in-hospital mortality. All strains were susceptible to gentamicin and meropenem; none carried an AbaR resistance island. Our results suggest that international dissemination of A. baumannii is occurring in the community on a contemporary timescale. Genes associated with biofilm formation and the T6SS may not be required for survival in community niches. The relative contributions of host and bacterial factors to the clinical severity of community-onset A. baumannii infection require further investigation.

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Dataset Information

ICU-associated Acinetobacter baumannii colonisation/infection in a high HIV-prevalence resource-poor setting.

Background

Methods

Results

Publications

ICU-associated Acinetobacter baumannii colonisation/infection in a high HIV-prevalence resource-poor setting.

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