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The emerging threat of multidrug-resistant Gram-negative bacteria in urology

Key Points

  • Multidrug-resistant Gram-negative pathogens are rapidly emerging and spreading globally

  • These multidrug-resistant pathogens are frequently associated with major pathologies, including urinary tract infections

  • Routine urological practices are affected by multidrug-resistant pathogens

  • Knowledge of the local epidemiology of multidrug-resistant Gram-negative bacteria is essential for determining empirical antimicrobial therapy

Abstract

Antibiotic resistance in Gram-negative uropathogens is a major global concern. Worldwide, the prevalence of Enterobacteriaceae that produce extended-spectrum β-lactamase or carbapenemase enzymes continues to increase at alarming rates. Likewise, resistance to other antimicrobial agents including aminoglycosides, sulphonamides and fluoroquinolones is also escalating rapidly. Bacterial resistance has major implications for urological practice, particularly in relation to catheter-associated urinary tract infections (UTIs) and infectious complications following transrectal-ultrasonography-guided biopsy of the prostate or urological surgery. Although some new drugs with activity against Gram-negative bacteria with highly resistant phenotypes will become available in the near future, the existence of a single agent with activity against the great diversity of resistance is unlikely. Responding to the challenges of Gram-negative resistance will require a multifaceted approach including considered use of current antimicrobial agents, improved diagnostics (including the rapid detection of resistance) and surveillance, better adherence to basic measures of infection prevention, development of new antibiotics and research into non-antibiotic treatment and preventive strategies.

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Figure 1: Infection and resistance in urological practice.
Figure 2: Global epidemiology of resistance in Gram-negative uropathogens—fluoroquinolones.
Figure 3: Global epidemiology of resistance in Gram-negative uropathogens—third-generation cephalosporins.
Figure 4: Global epidemiology of resistance in Gram-negative uropathogens—carbapenems.

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Acknowledgements

H.M.Z. acknowledges an academic scholarship from the government of Saudi Arabia to pursue postgraduate studies in the field of clinical microbiology and infectious diseases, and research support from the Ministry of National Guard, Health Affairs, King Abdullah International Medical Research Centre, Saudi Arabia (project no. IRBC/193/12). P.N.A.H. is supported by an Australian Postgraduate Award from the University of Queensland, Australia. M.J.R. is supported by a Doctor in Training Research Scholarship from Avant Mutual Group Ltd., a Cancer Council Queensland PhD Scholarship and Professor William Burnett Research Fellowship from the Discipline of Surgery, School of Medicine, The University of Queensland, Australia.

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H.M.Z., P.N.A.H., M.J.R. and M.D.P. researched data for the article, all authors provided a substantial contribution to the discussion of content, H.M.Z., P.N.A.H., M.J.R., P.A.T., M.A.S., M.D.P. and D.L.P. helped write the article, and all authors reviewed/edited the manuscript before submission. H.M.Z. and P.N.A.H should be considered joint first authors on the manuscript.

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Correspondence to Hosam M. Zowawi.

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P.A.T. has received research support from ADAMAS, Baxter, Fabentech, Inviragen, Merlion Pharmaceuticals and Sanofi Pasteur, and has received honoraria from AstraZeneca and Novartis. D.L.P. has participated in advisory boards and received honoraria from AstraZeneca, Bayer, Cubist, Leo Pharmaceuticals, Merck and Pfizer. The other authors declare no competing interests.

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Studies reporting resistance in Gram-negative uropathogens published 2009–2014 (DOC 127 kb)

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Zowawi, H., Harris, P., Roberts, M. et al. The emerging threat of multidrug-resistant Gram-negative bacteria in urology. Nat Rev Urol 12, 570–584 (2015). https://doi.org/10.1038/nrurol.2015.199

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